WEBVTT - From the Vault: Cambrian Monster Mash 0:00:05.760 --> 0:00:07.760 Hey, you welcome to stuff to blow your mind. My 0:00:07.840 --> 0:00:10.920 name is Robert Lamb and I'm Joe McCormick. And it's Saturday. 0:00:11.160 --> 0:00:14.000 Time to venture into the vault for an exploration of 0:00:14.040 --> 0:00:16.840 the Cambrian era. Oh yes, this is an exciting one. 0:00:16.880 --> 0:00:21.400 This one published just last year October. That's right, And 0:00:21.480 --> 0:00:24.080 so this was going to be an episode about Cambrian 0:00:24.160 --> 0:00:27.840 monster was going to be It was one, definitively say, 0:00:27.960 --> 0:00:32.000 it is one about about Cambrian animals and and their 0:00:32.080 --> 0:00:35.760 their monstrous characteristics, and about evolutionary biology. We get into 0:00:35.800 --> 0:00:39.200 some interesting theories about what caused the so called Cambrian explosion. 0:00:39.640 --> 0:00:42.159 So this was an October episode. We're running it in November. 0:00:42.200 --> 0:00:45.360 Are we cheating a little bit? We extending the October? Oh? Yeah, 0:00:45.360 --> 0:00:48.800 we're doing a little Halloween hangover, little Halloween hang around. 0:00:48.880 --> 0:00:52.000 I don't know that Halloween gets gets to last until 0:00:52.200 --> 0:00:55.000 the coming of Crampus in my book. So okay, haven't 0:00:55.120 --> 0:00:57.400 we Ultimately we have another month or so that we 0:00:57.400 --> 0:01:01.080 can continue to to dip into the monster bucket here. Um, 0:01:01.240 --> 0:01:03.800 I do want to say on this particular episode, we 0:01:03.880 --> 0:01:07.080 also have some merchandise to go along with it. We 0:01:07.120 --> 0:01:10.960 have a fabulous new logo design which takes our existing 0:01:11.040 --> 0:01:13.840 logo the sort of abstract symbol that you associated with 0:01:13.840 --> 0:01:16.520 Stuff to Blow your Mind, and it positions it within 0:01:16.760 --> 0:01:20.480 uh kind of a Cambrian sea of strange life forms. 0:01:21.040 --> 0:01:24.920 And that logo is available on a shirt, on a throat, pillow, 0:01:25.000 --> 0:01:27.600 on a sticker, UH, you name it. You can get 0:01:27.640 --> 0:01:30.280 it through our t public store. There's a link for 0:01:30.319 --> 0:01:32.040 that at the top of our homepage. It's Stuff to 0:01:32.040 --> 0:01:34.759 Blow your Mind dot com. And if you're looking at 0:01:34.800 --> 0:01:38.760 this particular episode on our website, there you'll also see 0:01:38.880 --> 0:01:41.680 that image front and center as the lead image for 0:01:41.720 --> 0:01:44.080 this episode. Can you get it engraved on a belt buckle? 0:01:44.160 --> 0:01:45.560 They do belt buckle. I don't know if they do 0:01:45.600 --> 0:01:48.360 belt buckles yet, but it's probably. There's there's a lot 0:01:48.440 --> 0:01:50.640 of of of possibility. You can do hoodies, you can 0:01:50.640 --> 0:01:53.000 do like various types of shirts. And I bring this up, 0:01:53.120 --> 0:01:55.240 I mean mainly because it's fun and it's a great 0:01:55.240 --> 0:01:57.400 way to share Stuff to Blow your Mind and the 0:01:57.400 --> 0:01:59.960 stuff to Blow your Mind message, I guess you would say, 0:02:00.000 --> 0:02:01.560 with everyone. But it's also a great way to support 0:02:01.600 --> 0:02:04.600 the show, UH. Spending a little money on some cool 0:02:04.640 --> 0:02:06.880 merchandise that is kind of a kind of a wink 0:02:06.920 --> 0:02:09.880 to other folks who may be listening as well. Alright, well, 0:02:09.919 --> 0:02:12.480 with that, i'd say let's jump right into our episode 0:02:12.480 --> 0:02:27.320 on the Cambrian Monster Mash. Hello Dr jessup, anybody here? Well, hello, 0:02:27.440 --> 0:02:31.320 good sir. I'm glad to see you have arrived. I 0:02:31.360 --> 0:02:33.800 apologize I can't be there to greet you in person, 0:02:33.919 --> 0:02:37.959 but please know that I am most appreciative of your attendance. 0:02:38.240 --> 0:02:41.359 It's so hard to find good volunteers these days. It's 0:02:41.600 --> 0:02:44.520 it's just if every undergraduate rely even a bit of 0:02:44.639 --> 0:02:50.519 backbonus simply vanished in the past six months. Huh okay, 0:02:50.680 --> 0:02:53.679 So am I in the right place? Ah? Well, well, 0:02:53.720 --> 0:02:56.480 perhaps instead you should ask whether you were in the 0:02:56.639 --> 0:03:01.720 right time. Uh well, the flyer said, you doing SIUR 0:03:01.840 --> 0:03:07.400 for test subjects in something called Middle Cambrian exposure. I'm 0:03:07.400 --> 0:03:09.800 not sure what that is, but if you're paying cash, 0:03:09.840 --> 0:03:13.280 I'm still on board. Excellent. Now tell me do you 0:03:13.320 --> 0:03:18.520 have any experience with time displacement? I don't think so, 0:03:18.840 --> 0:03:22.639 of course not, of course not. And tell me can 0:03:22.720 --> 0:03:25.079 you swim? You know I can, but it's one of 0:03:25.160 --> 0:03:30.240 those things I wouldn't say. I'm a great swimmer. Nobody's perfect. 0:03:31.200 --> 0:03:35.600 Do you see the throbbing light lucifortex in the center 0:03:35.640 --> 0:03:40.080 of the room or well, yeah, yeah, I do, excellent, 0:03:41.000 --> 0:03:47.640 go to it all right? Yes, yes, closer, closer? Doesn't 0:03:47.640 --> 0:03:52.120 feel right? What's that feeling? What's the matter, my little vertebrate? 0:03:52.240 --> 0:03:57.080 Haven't you ever wanted to feel? Five hundred million years younger? 0:03:57.800 --> 0:04:02.560 What is that? Is that? An ocean? Oh? My god, 0:04:03.120 --> 0:04:13.320 it's like the whole planet's an ocean. It's full of monsters. 0:04:13.320 --> 0:04:16.440 Welcome to Stuff to Blow your Mind from how Stuffworks 0:04:16.440 --> 0:04:24.960 dot Com. Hey, welcome to Stuff to Blow your mind. 0:04:25.000 --> 0:04:27.799 My name is Robert Lamb and I'm Joe McCormick and Robert. 0:04:27.800 --> 0:04:30.480 That was obviously a reference to some kind of journey 0:04:30.480 --> 0:04:33.800 we may be taking to the Cambrian period. That's right. Yeah, 0:04:33.800 --> 0:04:37.280 we had a little cameo by the late great Anton 0:04:37.400 --> 0:04:40.040 Jessa late did he die? I don't know. I mean 0:04:40.040 --> 0:04:42.680 there there are rumors of his death, but who knows 0:04:42.720 --> 0:04:45.640 for sure? That always exaggerated, is well? Anyway, today, I've 0:04:45.680 --> 0:04:47.080 got a little story I want to tell to lead 0:04:47.160 --> 0:04:50.279 us into our topic. Now. Obviously it is October. It's 0:04:50.279 --> 0:04:52.400 our favorite time of year to talk about monsters. We 0:04:52.440 --> 0:04:54.599 talked about monsters anyway, but this is the time where 0:04:54.600 --> 0:04:57.920 we really double down. It's clear mandate for monsters. And 0:04:58.040 --> 0:05:01.440 I got to take a monster science It's adventure this 0:05:01.520 --> 0:05:04.240 past month. So this this past month, early on one 0:05:04.240 --> 0:05:07.880 Sunday morning, my wife Rachel and I were in Canada 0:05:07.960 --> 0:05:10.359 and we woke up before dawn on this Sunday morning 0:05:10.360 --> 0:05:13.880 in the town of Golden British Columbia. It's in western Canada, 0:05:13.920 --> 0:05:17.360 the Canadian Rockies, and we had some coffee and bagels, 0:05:17.360 --> 0:05:19.120 and we filled up our backpacks with a bunch of 0:05:19.240 --> 0:05:22.680 layers of warm clothes, bottles of water, all that hiking stuff, 0:05:22.720 --> 0:05:25.480 and we drove along the steep mountain sides to this 0:05:25.560 --> 0:05:29.920 tiny town called Field in British Columbia. And there we 0:05:30.000 --> 0:05:32.960 parked beside a gas station and we waited to meet 0:05:33.000 --> 0:05:36.680 our guide and the rest of this tour group. So 0:05:36.720 --> 0:05:40.120 the guide was a paleontologist named David, and the hiking 0:05:40.120 --> 0:05:43.680 group was mostly French speaking families, some really lovely people 0:05:43.800 --> 0:05:47.159 and some very intelligent children with great questions like why 0:05:47.279 --> 0:05:51.840 do animals die? Uh? And so we hiked through the 0:05:51.839 --> 0:05:54.839 town of Field and along this uphill path through the 0:05:54.880 --> 0:05:58.240 forest up the side of Mount Stephen, and as we 0:05:58.279 --> 0:06:00.800 went on throughout the day, the trail got steeper and steeper, 0:06:01.240 --> 0:06:03.240 and we could see through the trees. The town we 0:06:03.320 --> 0:06:07.000 came from was becoming this tiny miniature model in the distance. 0:06:07.000 --> 0:06:09.359 And then right around midday we came out of the 0:06:09.400 --> 0:06:12.320 tree line and we walked up on this bare plane 0:06:12.360 --> 0:06:15.839 of flat rocks and they were pieces of the underlying 0:06:15.880 --> 0:06:18.960 shale formation that had chipped and broken off, and they 0:06:19.120 --> 0:06:22.080 gathered in this relatively flat part of the mountain side. 0:06:22.480 --> 0:06:25.080 And on this plane of rocks, you walk around and 0:06:25.120 --> 0:06:29.120 you pick up these mineral fragments and they're full of fossils. 0:06:29.800 --> 0:06:33.680 It's just fossils everywhere. Almost every other rock you find 0:06:33.760 --> 0:06:36.479 has the shape of an animal from millions of years 0:06:36.480 --> 0:06:41.000 ago printed into it. You're literally walking on thousands and 0:06:41.160 --> 0:06:45.159 thousands of fossils. So you're in this this mountainous environment 0:06:45.680 --> 0:06:48.160 and David, who by the way, i'm picturing as the 0:06:48.200 --> 0:06:51.919 Android from Prometheus and Alien Covenant, is guiding you and 0:06:52.000 --> 0:06:55.719 showing you these these prehistoric remnants in the rock. David 0:06:55.839 --> 0:06:59.000 was not Michael Fastbender, but David was excellent. He was 0:06:59.040 --> 0:07:01.400 a really, really good guy. And this place we came 0:07:01.440 --> 0:07:04.279 to where we were walking on fossils. This was the 0:07:04.279 --> 0:07:07.680 Mount Stephen Trial Bye beds. It is a graveyard of 0:07:07.760 --> 0:07:12.440 organisms from the Cambrian Period about five hundred million years ago. Now. 0:07:12.520 --> 0:07:15.000 Mount Stephen is in an area that's home to the 0:07:15.000 --> 0:07:18.400 Burgess Shale geological Formation, which is one of the most 0:07:18.440 --> 0:07:22.440 important sites of Cambrian Period fossils in the world. And 0:07:22.480 --> 0:07:24.120 if you ever get a chance to do one of 0:07:24.160 --> 0:07:27.239 these hikes, I highly highly recommended. I think it literally 0:07:27.280 --> 0:07:29.760 might be the coolest thing I've ever done. You have 0:07:29.800 --> 0:07:32.480 to book them through this organization called the Burgess Shale 0:07:32.600 --> 0:07:36.200 Geoscience Foundation, and they pair you with a guide. Our guide, David, 0:07:36.240 --> 0:07:39.560 the paleontologist, was an excellent science communicator. He was really 0:07:39.560 --> 0:07:41.160 good with the kids on the group, and he was 0:07:41.200 --> 0:07:43.080 a great hiking guide. So if you get a chance 0:07:43.160 --> 0:07:46.120 to go with David, big thumbs up to him. Be 0:07:46.240 --> 0:07:48.240 warned if you do try to do this, it's a 0:07:48.240 --> 0:07:52.480 tough hike. It's like eight kilometers round trip horizontally with 0:07:52.600 --> 0:07:56.600 a seven hundred and ninety five meter elevation gain, which 0:07:56.680 --> 0:08:00.320 is like two thousand, six hundred feet, and and that's 0:08:00.360 --> 0:08:04.320 starting at like twelve hundred or hundred meters of elevation 0:08:04.440 --> 0:08:06.840 at the at the base of the mountain. Uh So, 0:08:06.960 --> 0:08:09.240 the air is thin, and it's worth doing some other 0:08:09.320 --> 0:08:11.880 hikes at higher elevation to get yourself accustomed to the 0:08:12.000 --> 0:08:14.320 lack of oxygen. But I also don't want to scare 0:08:14.360 --> 0:08:17.360 you too much, obviously I will. I am no kind 0:08:17.360 --> 0:08:20.960 of athlete or experienced altitude hiker or anything like that, 0:08:21.040 --> 0:08:23.840 and I survived so beer advising listeners to wear their 0:08:23.840 --> 0:08:27.440 best flip flops on this particular Just be prepared, have 0:08:27.560 --> 0:08:31.200 some layers, have some water, do a little practice. If 0:08:31.280 --> 0:08:33.840 you can make the trip, it is absolutely worth it 0:08:33.920 --> 0:08:36.280 to see these fossils firsthand. You can pick them up. 0:08:36.320 --> 0:08:40.120 You can feel the ribs of these Cambrian organisms. You 0:08:40.120 --> 0:08:42.720 can you can feel the contours of their bodies as 0:08:42.760 --> 0:08:46.480 they printed on this ancient shale. But also it's really 0:08:46.480 --> 0:08:48.959 cool to be there, just because the area around field, 0:08:49.000 --> 0:08:52.520 including Mount Stephen, trial By Beds and the Burgess Shale 0:08:52.600 --> 0:08:56.480 Quarry quarries, are just arguably the most important Cambrian fossil 0:08:56.559 --> 0:08:59.840 sites in the world. They are a geological window in 0:09:00.040 --> 0:09:04.800 to a time stranger I would argue than any alien 0:09:04.880 --> 0:09:08.600 planet in any movie, any book, any video game, any 0:09:08.600 --> 0:09:12.800 Star Trek episode. I think the real alien monsters. Uh. 0:09:12.840 --> 0:09:14.720 And of course, as you if you know the show, 0:09:14.760 --> 0:09:17.720 you know we use the term monster affectionately. It's not 0:09:17.760 --> 0:09:21.200 a pejorative. The real alien monsters are not out there 0:09:21.240 --> 0:09:25.199 on some exoplanet. They were right here five hundred million 0:09:25.280 --> 0:09:27.760 years ago, and in this one amazing place you can 0:09:27.800 --> 0:09:32.480 sort of crunch through their frozen graveyard and it's awesome. Now, Joe, 0:09:32.520 --> 0:09:36.440 do you find yourself falling into the same admittedly dumb 0:09:36.440 --> 0:09:38.880 trap that I do when I when I think about 0:09:39.640 --> 0:09:44.960 about the nationalities that are sort of overlaid regarding fossil 0:09:45.200 --> 0:09:50.600 uh finds like these are Canadian Cambrian monsters or something 0:09:50.640 --> 0:09:53.160 like that. Like, yeah, because I was recently reading to 0:09:53.240 --> 0:09:55.760 my son about Terra saurs and was reading about the 0:09:55.840 --> 0:10:01.040 about about Bavarian fossils of Terra saurs, and is as 0:10:01.120 --> 0:10:04.360 silly as it is, I couldn't help but think of 0:10:04.360 --> 0:10:09.440 of Bavarian Terra stars thinking about the very in rhistoric creature, 0:10:09.520 --> 0:10:12.800 like wearing later hosen the big big stein of beer. 0:10:12.960 --> 0:10:14.960 And it's so unfair. You know, I've done the same 0:10:14.960 --> 0:10:18.640 thing thinking of Mongolian fossil finds in our previous episode, 0:10:18.640 --> 0:10:21.880 we talked about various raptors. I believe Kim remember it 0:10:21.960 --> 0:10:26.280 was the velociraptor or dononicus. But I could not help 0:10:26.320 --> 0:10:29.080 but then think about them in terms of like human 0:10:29.160 --> 0:10:35.640 history regarding that area, and it yeah, part of his pack. 0:10:36.400 --> 0:10:38.600 Uh yeah, yeah, I know exactly what you're talking about. 0:10:38.640 --> 0:10:41.760 And that does highlight the need to sort of explain 0:10:41.960 --> 0:10:45.280 how the Cambrian world was so different than our world, 0:10:45.360 --> 0:10:47.360 not just that it had different animals in it, but 0:10:47.400 --> 0:10:49.640 that planet Earth was different than So when I say 0:10:49.679 --> 0:10:52.800 it was an alien planet, I mean that quite literally. 0:10:52.880 --> 0:10:55.920 It's not just that it had different fauna, it was 0:10:55.960 --> 0:10:59.120 a It was a totally different place to live. And 0:10:59.160 --> 0:11:02.640 so before we get into exploring these monsters of the 0:11:02.640 --> 0:11:06.120 Cambrian Period, these beautiful and bizarre creatures that you couldn't 0:11:06.160 --> 0:11:09.040 even dream up if you tried, I think we should 0:11:09.040 --> 0:11:11.760 take a look at the Cambrian period itself and explain 0:11:11.840 --> 0:11:16.360 what it was like to be Terra five million years ago. 0:11:17.280 --> 0:11:20.360 So the Cambrian Period lasted from about five hundred forty 0:11:20.400 --> 0:11:23.040 to about four hundred and eighty five million years ago, 0:11:23.120 --> 0:11:26.560 and if you were dropped from today straight into the 0:11:26.600 --> 0:11:30.400 Cambrian period, you would not recognize planet Earth. The Earth, 0:11:30.520 --> 0:11:33.640 for one thing, revolved faster than it does now, so 0:11:33.800 --> 0:11:37.040 days were only about twenty one hours long, and there 0:11:37.040 --> 0:11:39.400 were about four hundred and twenty of them in a year. 0:11:40.440 --> 0:11:43.600 The air would be hot, so the average global surface 0:11:43.640 --> 0:11:46.880 temperature would have been about ten degrees celsius hotter than today. 0:11:47.040 --> 0:11:50.080 That's a good bit hotter. The atmosphere, while it did 0:11:50.160 --> 0:11:53.200 have significant free oxygen, at this point, was not quite 0:11:53.240 --> 0:11:54.840 what it is today. It would have felt a little 0:11:54.880 --> 0:11:58.960 bit thick with carbon dioxide in your lungs. If you 0:11:59.000 --> 0:12:02.240 happen to see dry land, it would probably look more 0:12:02.360 --> 0:12:05.960 like the surface of Mars than Earth today. Because land 0:12:06.080 --> 0:12:10.040 dwelling plants didn't exist yet. It's kind of hard to 0:12:10.080 --> 0:12:13.680 imagine Earth that way. And without plant roots to hold 0:12:13.720 --> 0:12:17.200 the soil in place, land surfaces eroded very easily in 0:12:17.240 --> 0:12:19.959 the wind and the churning water. So you know, the 0:12:20.360 --> 0:12:23.480 continents are constantly just kind of burning away into the 0:12:23.520 --> 0:12:26.280 oceans and being reformed. So to call back to a 0:12:26.320 --> 0:12:29.480 previous episode we did, was this was definitely a world 0:12:29.480 --> 0:12:32.560 before fire. Oh yeah, because what would it what would 0:12:32.559 --> 0:12:35.280 it burn? Right? Yeah? I mean, I can't be sure 0:12:35.280 --> 0:12:38.000 it was totally without fire, but I mean, yeah, obviously 0:12:38.040 --> 0:12:40.280 not fire on the scale we see of wildfires in 0:12:40.360 --> 0:12:43.200 forests today because there was oxygen in the atmosphere at 0:12:43.200 --> 0:12:45.720 this point. But yeah, what what would burn? What would 0:12:45.720 --> 0:12:48.720 the fuel be? All Right, So we have this alien 0:12:48.760 --> 0:12:53.400 world with just a barren land when visible, and then 0:12:53.440 --> 0:12:56.480 we have this this ocean, this strange ocean, and the 0:12:56.520 --> 0:12:59.800 Cambrians earth that that's not a story about land at all. 0:12:59.840 --> 0:13:02.319 That is a story about ocean. It was the ocean 0:13:02.360 --> 0:13:05.280 planet at that point. You could probably make the argument 0:13:05.280 --> 0:13:08.120 it's the ocean planet right now, but it definitely was then. 0:13:08.480 --> 0:13:12.040 According to Cambrian Ocean World Ancient Sea Life of North 0:13:12.080 --> 0:13:15.840 America by John Foster uh, the level of the seas 0:13:16.080 --> 0:13:19.120 rose steadily in this saw tooth rise and fall pattern 0:13:19.160 --> 0:13:21.440 throughout the Cambrian period. So at the beginning of the 0:13:21.480 --> 0:13:24.040 period sea level was actually a little bit lower than 0:13:24.080 --> 0:13:26.400 it is today, But by the end of the Late 0:13:26.440 --> 0:13:30.239 Cambrian sea level was about a hundred and sixty meters 0:13:30.320 --> 0:13:33.120 or five and thirty feet higher than it is today. 0:13:33.160 --> 0:13:39.319 So in today's terms, New York Underwater Rome underwater, paris underwater, 0:13:39.520 --> 0:13:43.880 bag Dad underwater, even parts of Moscow underwater, and the 0:13:43.960 --> 0:13:46.280 high sea level in the Cambrian led to flooding of 0:13:46.320 --> 0:13:50.600 about forty percent of the area of Earth's continental masses. 0:13:50.800 --> 0:13:53.520 Compared that to today, we're only about five percent of 0:13:53.520 --> 0:13:56.880 that continental area is covered in water. So most of 0:13:56.880 --> 0:14:00.439 our planets dry land mass was gathered together closer to 0:14:00.520 --> 0:14:04.040 the south pole, and the continent that became North America 0:14:04.200 --> 0:14:07.320 was then called Laurentia, not than called by people who 0:14:07.320 --> 0:14:11.280 have been but people today called that continent than Laurentia. 0:14:11.679 --> 0:14:15.280 And you sort of have to imagine North America turned sideways, 0:14:15.480 --> 0:14:20.160 mostly flooded, straddling the equator. Also adding to the alien 0:14:20.240 --> 0:14:23.480 quality in the Cambrian, astronomy would have been a little 0:14:23.480 --> 0:14:27.240 bit different. So the Moon was more than twenty kilometers 0:14:27.320 --> 0:14:30.440 closer to Earth than meaning that its gravity was stronger, 0:14:30.880 --> 0:14:33.560 meaning the high and low tides on Earth were higher 0:14:33.560 --> 0:14:36.800 and lower. Okay, because you know, my son was just 0:14:36.840 --> 0:14:39.040 talking to him to me the other day about the 0:14:39.200 --> 0:14:42.520 size of the moon and prehistoric times. Oh yeah, like 0:14:42.600 --> 0:14:45.600 he knew that the moon was bigger in prehistoric times. Yeah, 0:14:45.640 --> 0:14:47.560 and uh, and knows that it will be it will 0:14:47.600 --> 0:14:50.960 be smaller in future times. Did he into it that 0:14:51.080 --> 0:14:53.800 or did he find that out somewhere. He consumes a 0:14:53.800 --> 0:14:58.840 lot of Dinosaur Train and he really likes this podcast, 0:14:58.840 --> 0:15:02.160 Wow in the World, that's great science podcast for for kids. 0:15:02.200 --> 0:15:04.560 So and then you know, we talked to him a 0:15:04.560 --> 0:15:06.840 lot about science. Man, I wish I was that cool 0:15:06.880 --> 0:15:08.680 when I was a kid. I probably just would have 0:15:08.680 --> 0:15:11.000 told you about like which ninja turtle was bigger in 0:15:11.040 --> 0:15:13.720 the prehistoric times? Yeah, so far Ninja turtles will probably 0:15:13.760 --> 0:15:15.840 come in and wash it all the way. But for now, 0:15:15.880 --> 0:15:18.880 he's really really into the science, like an alien ocean 0:15:19.040 --> 0:15:22.560 driving away the continents. Okay, So if we looked under 0:15:22.600 --> 0:15:26.520 that ancient ocean, that's where the real craziness comes in, 0:15:26.600 --> 0:15:31.040 because we would find this vast realm of gorgeous, terrifying, 0:15:31.240 --> 0:15:35.680 surreal monsters that would look completely unlike the kind of 0:15:35.720 --> 0:15:39.280 Earth life we're familiar with today. Because the Cambrian period 0:15:39.320 --> 0:15:41.520 is the geological layer where we see evidence of one 0:15:41.560 --> 0:15:44.600 of the most fascinating and mysterious events in the history 0:15:44.600 --> 0:15:49.880 of life on Earth, known as the Cambrian explosion. So explosion. 0:15:50.000 --> 0:15:53.480 What exploded? Was this like a bunch of volcanoes or something. No, 0:15:53.920 --> 0:15:59.040 the Cambrian explosion is a story about bio diversity. So, Robert, 0:15:59.080 --> 0:16:01.640 how old is the Earth? Oh, it's so at four 0:16:01.680 --> 0:16:03.920 and a half billion years old. Yeah, that's the general 0:16:03.960 --> 0:16:06.880 astronomical idea. So four and a half billion years old. 0:16:07.080 --> 0:16:09.640 We've had this planet roughly, and we know there's been 0:16:09.920 --> 0:16:12.560 single celled life on the planet for at least maybe 0:16:12.600 --> 0:16:15.000 three and a half billion years or so, based on 0:16:15.440 --> 0:16:19.320 fossil traces left behind by these organisms. And new findings 0:16:19.400 --> 0:16:23.000 keep pushing the debatable frontier of earliest life farther and 0:16:23.040 --> 0:16:26.200 farther back into the darkness of Earth time. One example, 0:16:26.200 --> 0:16:29.040 I just came across So the other day, just earlier 0:16:29.040 --> 0:16:31.920 this year, in March, there was an article published in 0:16:32.000 --> 0:16:35.880 Nature arguing that apparent microbe fossils in the New vo 0:16:36.000 --> 0:16:40.080 Agatuck Belt in Quebec are about three point eight billion 0:16:40.120 --> 0:16:44.080 and possibly four point three billion years old, somewhere in 0:16:44.120 --> 0:16:47.800 that range, and these single celled life forms would have 0:16:47.840 --> 0:16:51.800 been surviving around hydrothermal vents and had this biochemistry based 0:16:51.840 --> 0:16:56.760 on eating and excreting iron. That's pretty rough and tumble. 0:16:56.840 --> 0:16:59.880 That's like a comic book film, right, yeah, the iron eat. 0:17:00.520 --> 0:17:03.080 And the crazy thing is that if these findings are correct, 0:17:03.200 --> 0:17:05.880 life on Earth would have began within just a few 0:17:06.040 --> 0:17:10.120 hundred million years of the planet first accreting together in space. 0:17:10.280 --> 0:17:12.879 It's kind of hard to believe, but whether life on 0:17:12.920 --> 0:17:15.760 Earth began like four point two billion years ago or 0:17:15.880 --> 0:17:18.760 more recently, we know that for a long, long time, 0:17:19.440 --> 0:17:23.280 life on Earth wasn't becoming much more complex, right. There 0:17:23.320 --> 0:17:27.800 was no serious multicellular life. So no animals, no fish 0:17:27.840 --> 0:17:32.200 and reptiles, no birds, no plants, no mushrooms, just microbial 0:17:32.359 --> 0:17:36.560 organisms like bacteria and archaea floating around in the oceans, 0:17:36.600 --> 0:17:41.159 forming mats and films and occasionally occasionally building these giant 0:17:41.240 --> 0:17:45.280 mineral brains in the surf called stromatallites. So this would 0:17:45.280 --> 0:17:47.560 be if this were a science fiction film, this would 0:17:47.600 --> 0:17:52.800 be the least cinematic alien life form encounter unless it 0:17:52.800 --> 0:17:55.680 made people like, you know, horribly sick obviously, or possessed them. 0:17:56.359 --> 0:17:59.639 Biofilm planet, yeah, yeah, the Planet of Slime. Yeah. There 0:17:59.680 --> 0:18:02.960 was the episode of of Star Trek that that does 0:18:03.000 --> 0:18:05.880 not does not make it to to the series. Yeah, 0:18:05.920 --> 0:18:08.080 and that's you know, that would have been the story 0:18:08.119 --> 0:18:11.560 of Earth for most of Earth's history, not having any 0:18:11.640 --> 0:18:14.080 kind of interesting animals or anything like that. Not to 0:18:14.119 --> 0:18:16.800 say that microbes aren't interesting in themselves, but maybe less 0:18:16.840 --> 0:18:19.840 interesting to look at. It would have been slime planet. Yeah. Generally, 0:18:19.880 --> 0:18:22.960 this is the stuff that occupies one, maybe two pages 0:18:23.080 --> 0:18:26.280 of a of a large prehistoric life book before you 0:18:26.320 --> 0:18:29.679 get onto the more exciting things, the things that children 0:18:29.680 --> 0:18:32.000 can imagine fighting each other. But it's most of the 0:18:32.040 --> 0:18:36.560 life that's ever happened. And then billions of years later, 0:18:36.640 --> 0:18:40.840 at the beginning of the Cambrian Period, something happens very suddenly. 0:18:41.680 --> 0:18:45.280 Loads of insane animals show up. And when I say suddenly, 0:18:45.359 --> 0:18:48.080 I have to qualify that that's suddenly from a geological 0:18:48.119 --> 0:18:51.200 point of view, which in reality means it took millions 0:18:51.200 --> 0:18:53.800 of years about five hundred and forty million years ago 0:18:53.840 --> 0:18:56.600 to about five hundred million years ago. But that's still 0:18:56.640 --> 0:18:59.399 pretty suddenly compared to the age of the Earth. And 0:18:59.440 --> 0:19:04.600 this g illogically rapid spike in animal diversity delivers creatures 0:19:04.600 --> 0:19:10.440 with bilateral symmetry, with large bodies, with eyes, with legs, 0:19:10.480 --> 0:19:14.560 with shells, with segmented body parts. You've got all of 0:19:14.600 --> 0:19:18.760 these crazy different types of creatures suddenly showing up, and 0:19:18.840 --> 0:19:21.680 it's like, where did they all come from? Yeah, it's 0:19:21.720 --> 0:19:24.200 like all these prototypes are rolled out at once. It's 0:19:24.240 --> 0:19:26.239 like the segment in is it is a RoboCop one 0:19:26.320 --> 0:19:29.920 or two where we get all the crazy prototypes that, oh, 0:19:30.000 --> 0:19:32.320 that's a RoboCop two. Yes, yeah, it's one of our 0:19:32.359 --> 0:19:35.280 favorite points of comparison on the show for biology. Yeah 0:19:35.720 --> 0:19:39.000 uh yeah. You have suddenly all these different, you know, 0:19:39.040 --> 0:19:43.399 seemingly crazy examples of life, and many of many of 0:19:43.400 --> 0:19:46.199 which don't seem to to fall in easily into that 0:19:46.280 --> 0:19:48.840 category of well, this is a precursor to something we 0:19:48.920 --> 0:19:51.080 have later on. It's a precursor to something we have 0:19:51.200 --> 0:19:54.400 today now. Of course, for some people with negative attitudes 0:19:54.480 --> 0:19:58.200 towards evolutionary science, this provides some kind of rhetorical ammunition, 0:19:58.359 --> 0:20:01.160 right indeed, I mean the explosion is often exploited by 0:20:01.200 --> 0:20:04.440 evolution of knives. Even Darwin, we have to note thought 0:20:04.480 --> 0:20:08.040 that the explosion was at odds with the normal evolutionary process, 0:20:08.160 --> 0:20:10.359 which in a funny way could be true, but not 0:20:10.520 --> 0:20:13.320 in the way an evolution denier would mean a couple 0:20:13.320 --> 0:20:16.760 of thoughts. Evolution is we're familiar with it today, tends 0:20:16.800 --> 0:20:20.399 to take place within ecosystems in which every niche is 0:20:20.440 --> 0:20:23.840 already filled. So basically every way there is for a 0:20:23.840 --> 0:20:26.399 creature to make a living, there's already something trying to 0:20:26.440 --> 0:20:28.280 do that, So if you want to compete, you've got 0:20:28.280 --> 0:20:32.320 to outcompete these other organisms. The global ocean of the Cambrian, 0:20:32.400 --> 0:20:35.080 on the other hand, represented a world in which it 0:20:35.119 --> 0:20:39.800 seems like there was still tremendous ecological opportunity to occupy, 0:20:40.080 --> 0:20:43.679 Like there was territory in the ecology that didn't have 0:20:43.760 --> 0:20:47.120 any existing competition. So it was a time in which 0:20:47.119 --> 0:20:49.840 an animal could start doing something to eat or to 0:20:49.920 --> 0:20:54.240 otherwise survive, and no other species was already doing that thing. 0:20:54.560 --> 0:20:57.000 There was just sort of like free land to grab. Yeah, 0:20:57.280 --> 0:21:00.600 like yeah, land grab call the frontier, uh, except without 0:21:00.680 --> 0:21:03.840 other organisms already occupying it. So that there could be 0:21:03.920 --> 0:21:07.680 one explanation for why evolution seems to be working differently 0:21:07.720 --> 0:21:10.600 at this one period in history than it has since. 0:21:11.080 --> 0:21:15.440 But also the Young Earth creationist who exploits ongoing debates 0:21:15.440 --> 0:21:19.520 in biology to sort of resort to the supernatural. They're 0:21:19.520 --> 0:21:22.920 employing a fallacy in rhetoric known as the argument from 0:21:22.920 --> 0:21:26.399 ignorance fallacy, which means like I don't know what caused something, 0:21:26.720 --> 0:21:31.480 therefore the cause is x uh example, you don't know 0:21:31.520 --> 0:21:34.359 who committed the Jack the Ripper murders. Therefore it was 0:21:34.400 --> 0:21:39.080 interdimensional sasquatches. Now the version employed here, of course, says, 0:21:39.200 --> 0:21:41.840 you can't all agree. We don't know on what caused 0:21:41.840 --> 0:21:45.359 the sudden or geologically sudden biodiversity of the Cambrian explosion. 0:21:45.680 --> 0:21:49.480 Therefore the cause is supernatural. Now, this line of thinking 0:21:49.480 --> 0:21:52.520 obviously doesn't get you anywhere once you examine it. But 0:21:52.720 --> 0:21:55.680 the disagreement and debate over the cause is a fascinating, 0:21:55.680 --> 0:21:58.000 outstanding question, and it's something I think we want to 0:21:58.119 --> 0:22:01.560 entertain a few answers to day. Now, some of the 0:22:01.640 --> 0:22:06.840 hypotheses are primarily environmental and chemical. Right, so some scientists 0:22:06.840 --> 0:22:09.440 have proposed that the cause of the camera and explosion 0:22:09.840 --> 0:22:12.760 could be a rise in the content of oxygen in 0:22:12.760 --> 0:22:15.520 the atmosphere, which leads to an increase in the level 0:22:15.560 --> 0:22:19.119 of dissolved oxygen in the oceans. Now, of course, remember 0:22:19.160 --> 0:22:22.800 that Earth's original atmosphere did not have free oxygen, right, 0:22:22.840 --> 0:22:25.840 that was added to the atmosphere gradually as a waste 0:22:25.840 --> 0:22:28.920 product of photosynthesis. You have all these microbes out there 0:22:29.160 --> 0:22:32.840 and they're eating the sunlight and then their geoengineering the 0:22:32.880 --> 0:22:36.520 atmosphere with their waste products. Which included oxygen. The gradual 0:22:36.640 --> 0:22:40.560 natural terraforming of our world. Yeah, the microbial terraforming of Earth, 0:22:40.600 --> 0:22:43.080 which absolutely did happen in the past. And that's where 0:22:43.080 --> 0:22:45.719 we get our oxygen. Now, when you think about it, 0:22:45.840 --> 0:22:49.760 large fast moving animals need lots of oxygen to feed 0:22:49.800 --> 0:22:52.720 their energy hungry tissues. Like think of the way that 0:22:52.760 --> 0:22:55.879 when you move your muscles a lot, your body starts 0:22:55.920 --> 0:22:59.880 greedily gulping down more and more air. In the same way, 0:23:00.040 --> 0:23:02.520 if you think about these organisms in the past, suddenly 0:23:02.560 --> 0:23:05.480 you wanted to have organisms with large bodies. They would 0:23:05.480 --> 0:23:08.840 have needed access to oxygen. So maybe when that oxygen 0:23:08.880 --> 0:23:12.520 became available, suddenly you could build these big, fast moving 0:23:12.560 --> 0:23:15.199 bodies and you get all this animal biodiversity. Okay, so 0:23:15.280 --> 0:23:19.600 previously the oxygen economy would not support this kind of growth, right, 0:23:19.640 --> 0:23:22.639 But the idea is then it would. So did a 0:23:22.680 --> 0:23:25.720 sudden increase in oxygen drive the explosion. Well, some recent 0:23:25.760 --> 0:23:29.160 studies have cast doubt on this hypothesis, including one published 0:23:29.160 --> 0:23:32.960 in Nature and by Spurling at all uh and it 0:23:33.080 --> 0:23:36.879 basically did not find evidence of a significant increase of 0:23:36.920 --> 0:23:39.600 oxygen in ocean water at the beginning of the Cambrian 0:23:40.000 --> 0:23:42.600 so evidence shows that if there was an increase in 0:23:42.640 --> 0:23:45.000 oxygen at the Cambrian transition, it was kind of a 0:23:45.040 --> 0:23:48.360 small one. All right, Well, what else do we have? Well, 0:23:48.359 --> 0:23:53.200 other hypotheses are more biological and ecological, Like what if 0:23:53.240 --> 0:23:57.560 there was one type of biological innovation, some new way 0:23:57.720 --> 0:24:01.440 for animals to make a living or new thing. Animals 0:24:01.480 --> 0:24:06.160 could do that rapidly accelerated competition with an ecosystems, which 0:24:06.160 --> 0:24:09.399 would speed up natural selection and cause new species to 0:24:09.480 --> 0:24:13.720 form much more rapidly. How about the example of site 0:24:14.000 --> 0:24:16.360 Oh yeah, this is a big one. Yeah, so previous 0:24:16.480 --> 0:24:20.040 animals they might have had some kind of photosensitive spots 0:24:20.160 --> 0:24:22.760 or receptors that would have allowed them to, for example, 0:24:22.960 --> 0:24:26.240 move towards the sunlight. But the Cambrian is the first 0:24:26.280 --> 0:24:30.280 period in history where we have evidence of complex site organs, 0:24:30.600 --> 0:24:34.000 you know, eyes. It's the age of organisms with compound eyes. 0:24:34.400 --> 0:24:37.280 So imagine how much adaptive pressure would be put on 0:24:37.359 --> 0:24:40.240 you if you lived in a world where all creatures 0:24:40.280 --> 0:24:44.280 were basically blind and then suddenly some of your competitors 0:24:44.280 --> 0:24:47.280 could see. Yeah, this is this is a crazy thing 0:24:47.320 --> 0:24:49.800 to try to imagine, but yeah, just just think of 0:24:49.880 --> 0:24:53.960 sight coming online in a world and all the additional 0:24:53.960 --> 0:24:57.800 stuff that this entail. Suddenly pigmentation begins to matter. I mean, 0:24:57.800 --> 0:25:01.040 it's hard to even apply. You're one is tempted to 0:25:01.080 --> 0:25:04.360 apply this to human arms race um, which is which 0:25:04.400 --> 0:25:08.479 is often an an apt comparison. But I mean, what 0:25:08.520 --> 0:25:12.080 can we even look to in human technology and human 0:25:12.080 --> 0:25:14.800 weapons systems. I mean, I'm just thinking maybe you could 0:25:14.800 --> 0:25:17.680 apply it. You can compare it to flight and say 0:25:17.680 --> 0:25:20.400 that well, once, once human technology allowed us to take 0:25:20.440 --> 0:25:25.119 to the air, that created an entire new theater of war, 0:25:25.320 --> 0:25:29.280 and they also changed the existing theaters of war. And 0:25:29.320 --> 0:25:31.520 I think you could make that comparison pretty well, like 0:25:31.880 --> 0:25:35.720 flight changed the nature of warfare forever, Like suddenly just 0:25:35.840 --> 0:25:38.520 having like lots of ground troops didn't didn't matter a 0:25:38.560 --> 0:25:42.200 whole lot, right, But this, this seems more extensive than that. 0:25:42.359 --> 0:25:45.600 You know, It's like it's it's the opening of another 0:25:45.680 --> 0:25:49.720 dimension of competition in a way. Yeah and yeah, and 0:25:49.760 --> 0:25:54.080 you think so you you mentioned pigmentation, Suddenly the colors 0:25:54.119 --> 0:25:56.920 you are matter, like blending in matters. But also think 0:25:56.920 --> 0:25:59.600 about the way it would make movement matter. We would 0:25:59.600 --> 0:26:03.040 make the shapes of bodies matter, would just completely change 0:26:03.080 --> 0:26:06.560 all the dynamics of how creatures interacted with one another. Yeah, 0:26:06.560 --> 0:26:11.280 not only prey predator interactions, but of course just interspecies communication, 0:26:11.560 --> 0:26:16.120 uh and as well as mating. I mean everything changes 0:26:16.160 --> 0:26:18.920 because of this. Yeah. So we'll come back to look 0:26:18.960 --> 0:26:22.800 at more of these answers to this question throughout the episode, 0:26:22.800 --> 0:26:24.399 but I think we should take our first break and 0:26:24.400 --> 0:26:25.920 then we come back. We will look at one of 0:26:25.960 --> 0:26:30.440 the first major inhabitants of our Cambrian monster House. Thank you, 0:26:30.640 --> 0:26:33.360 thank Alright, we're back. So as we roll through these, 0:26:33.400 --> 0:26:37.120 I also want everyone to think of potential Halloween costume ideas, 0:26:37.480 --> 0:26:39.879 because I think we have some We have some wonderful 0:26:40.080 --> 0:26:43.960 prehistoric monsters here that I think are more inventive listeners 0:26:44.000 --> 0:26:46.159 might be able to to turn into a mask or 0:26:46.240 --> 0:26:48.879 a full body cost Okay, So I want you Starship 0:26:48.920 --> 0:26:52.439 Troopers fans out there to get a little bit excited 0:26:52.480 --> 0:26:55.679 about Stone Bug Planet, Okay. Fans of the book or 0:26:55.760 --> 0:26:59.439 the movie, well, I mean they both got bugs, that's okay. 0:26:59.440 --> 0:27:03.119 So in eight teen six, there's a Canadian geologist by 0:27:03.119 --> 0:27:05.960 the name of Richard McConnell, and he's visiting the town 0:27:06.000 --> 0:27:08.280 of Field, the same town I went to when I 0:27:08.359 --> 0:27:11.760 began the walk up Mount stephen Field, British Columbia, where 0:27:11.800 --> 0:27:15.800 some railroad workers told him they had found something creepy 0:27:15.960 --> 0:27:19.080 on the slopes of nearby Mount stephen They were these 0:27:19.119 --> 0:27:23.879 things that they called quote stone bugs, and these were 0:27:23.920 --> 0:27:27.840 in fact trialo bytes, the best known inhabitants of the 0:27:27.840 --> 0:27:31.760 Cambrian oceans. Now trio bytes are not a single species, 0:27:31.800 --> 0:27:34.359 but there are a class of extinct animals from the 0:27:34.359 --> 0:27:37.080 phylum arthur Poda, and so that would be the same 0:27:37.080 --> 0:27:41.959 phylum that includes, for example, insects and crustaceans, lobsters or arthropods. 0:27:42.040 --> 0:27:47.399 Insects and spiders or arthropods. These exoskeleton creatures now trialo bytes, 0:27:47.440 --> 0:27:50.919 were an enormously successful form of life, beginning in the 0:27:50.960 --> 0:27:54.639 Cambrian and surviving for about three hundred million years until 0:27:54.680 --> 0:27:57.040 they were wiped out about two hundred and fifty million 0:27:57.119 --> 0:28:00.760 years ago in the Permian Triassic extinct Shinn event, also 0:28:00.800 --> 0:28:03.800 known as the Great Dying, which was the biggest mass 0:28:03.840 --> 0:28:08.000 extinction in the history of planet Earth. About of all 0:28:08.280 --> 0:28:13.240 marine species went extinct. It's kind of hard to imagine, 0:28:13.920 --> 0:28:16.520 but until then trial bytes were like sort of like 0:28:16.560 --> 0:28:21.439 the insects of today, just this enormously successful type of 0:28:21.600 --> 0:28:24.720 creature found everywhere. They were a swarm upon the face 0:28:24.760 --> 0:28:27.000 of the deep or I kind of want to think 0:28:27.000 --> 0:28:30.359 of them as the infinity bugs. I like it. So 0:28:30.640 --> 0:28:32.840 the trialo byte body structure kind of resembles like a 0:28:32.960 --> 0:28:36.000 roly poly or a pill bug, maybe crossed with a 0:28:36.040 --> 0:28:40.240 horseshoe crab. It's got these articulated segments lining its back 0:28:40.800 --> 0:28:42.360 and if you look at it from the top down, 0:28:42.400 --> 0:28:46.160 you'll see this flat, hard shell made of a matrix 0:28:46.200 --> 0:28:49.560 of tiny calcite needles. And if you look at it 0:28:49.600 --> 0:28:52.840 on the vulnerable underside, you'll see the legs and the 0:28:52.880 --> 0:28:55.120 gills and the mouth. And actually it does kind of 0:28:55.120 --> 0:28:57.200 look like a like a roly poly or a pill 0:28:57.240 --> 0:28:59.480 bug on the underside too, if you ever see them. Yeah, 0:28:59.480 --> 0:29:01.840 I have to say Trilobyte, of all the creatures were 0:29:01.840 --> 0:29:04.120 going to discuss today, well, first of all, it's the 0:29:04.160 --> 0:29:07.320 most famous, I think, so most of you have probably 0:29:07.400 --> 0:29:11.160 seen images of it before. But it also does look 0:29:11.160 --> 0:29:15.520 a lot more like existing creatures. It doesn't if you, 0:29:16.120 --> 0:29:18.320 if you didn't know better, you could easily see an 0:29:18.360 --> 0:29:20.320 image of this and think that it could be something 0:29:20.360 --> 0:29:23.360 living today. Yeah, I think the creepiness of the trial 0:29:23.440 --> 0:29:27.280 Bye World comes not from seeing their body plans, because 0:29:27.320 --> 0:29:29.400 you can see stuff that looks kind of like them. 0:29:29.440 --> 0:29:32.840 Like you say, it's just how many of them there were, 0:29:32.880 --> 0:29:35.640 and thinking of this being one of the dominant body 0:29:35.680 --> 0:29:39.080 plans on the planet, or the dominant body plan on 0:29:39.080 --> 0:29:41.000 the planet. And if you're still drawing a blank as 0:29:41.000 --> 0:29:44.000 to what this looks like, I'm going to include images 0:29:44.120 --> 0:29:46.400 of of all the species that we're discussing here on 0:29:46.440 --> 0:29:48.440 the landing page for this episode. It's stuff to blow 0:29:48.480 --> 0:29:51.080 your mind dot com. Alright, so we've had a look 0:29:51.080 --> 0:29:56.480 at the creature's legs. Let's turn this puppy around. Okay, 0:29:56.480 --> 0:29:57.960 turn it so if you look at it from the 0:29:58.000 --> 0:30:01.280 top down, you can basically deve via a trilobyte in 0:30:01.520 --> 0:30:04.720 three both ways. So if you look at it lengthwise, 0:30:04.760 --> 0:30:08.320 you're looking at head on. Lengthwise, there is bilateral symmetry, 0:30:08.360 --> 0:30:10.920 and this is the cameraan period. We see these animals 0:30:10.920 --> 0:30:14.160 with bilateral symmetry really taking over. You can fold them 0:30:14.200 --> 0:30:16.200 in half and they're like a book. They match on 0:30:16.240 --> 0:30:20.400 both sides. And in that lengthwise direction, the trilobyte is 0:30:20.400 --> 0:30:23.440 divided into three lobes. You've got the axial lobe, which 0:30:23.520 --> 0:30:25.800 runs down the middle from the head to the tail, 0:30:25.960 --> 0:30:27.760 kind of like the spine of the book, or like 0:30:27.840 --> 0:30:30.520 the spine of a vertebrate. And then you've got the 0:30:30.520 --> 0:30:33.560 two plural lobes on each side which you're shielding the 0:30:33.680 --> 0:30:36.600 legs from above. There were these you know, shelled lobes 0:30:36.640 --> 0:30:39.040 stick out on the side and they cover up where 0:30:39.040 --> 0:30:42.040 the legs would be moving underneath. Now you rotate at 0:30:42.120 --> 0:30:44.960 ninety degrees, and then you've got another three sections. You've 0:30:45.000 --> 0:30:48.440 got the head known as the cephalon, the middle section 0:30:48.480 --> 0:30:51.280 known as the thorax, and the rear section known as 0:30:51.360 --> 0:30:54.680 the pagidium. Now, one thing you might wonder, why do 0:30:54.720 --> 0:30:58.320 we see these articulated segments on the shell of a trilobyte, Like, 0:30:58.320 --> 0:31:01.160 why doesn't it have something more like a big solid 0:31:01.320 --> 0:31:06.480 turtle shell? You know, why why the different plates overlapping? Well, 0:31:06.560 --> 0:31:11.120 there are multiple answers, but one is that apparently some 0:31:11.240 --> 0:31:14.400 TrailO bites were able to partially curl up and protect 0:31:14.440 --> 0:31:19.520 their soft underbellies like an armadillo or a pillbug. Yeah 0:31:19.720 --> 0:31:22.160 it so do you do you use the word pillbug 0:31:22.240 --> 0:31:25.040 or roly poly? Do I think they're the same thing? Yes, 0:31:25.160 --> 0:31:27.520 I believe the same creature or the same you know, 0:31:27.680 --> 0:31:30.760 classification of creatures at the very least. But yeah, I 0:31:30.800 --> 0:31:33.240 grew up with roly poly. I think I did too, 0:31:33.280 --> 0:31:36.200 And somehow in my adulthood transition to pillbug, I've sold 0:31:36.200 --> 0:31:40.720 out my childhood wonders. It does sound significantly less silly. Well, anyway, 0:31:40.880 --> 0:31:43.920 trialo bite fossils are that. That's what you're walking on 0:31:43.960 --> 0:31:45.920 in the Mount Stephen Trialo by beds, right, So you 0:31:45.920 --> 0:31:48.120 walk around, you crunch through these things. You pick up 0:31:48.120 --> 0:31:50.600 these rocks and they've got these little shells in them. 0:31:50.800 --> 0:31:54.160 And the trio bite fossils are so common you can 0:31:54.200 --> 0:31:56.880 get the sense that these animals must have been stacked 0:31:56.920 --> 0:32:00.640 a mile high when they actually existed. Right, There were 0:32:00.680 --> 0:32:03.560 a lot of them in the Cambrian but they're perhaps 0:32:03.640 --> 0:32:06.800 overrepresented in the fossil record because many of the fossilized 0:32:06.840 --> 0:32:10.920 shells we find are not the animals themselves, but the 0:32:11.000 --> 0:32:15.800 discarded shells left over from the molting process. So, like 0:32:15.960 --> 0:32:18.840 Arthur pods today, trial bites were himmed in by this 0:32:18.920 --> 0:32:21.880 protective shell and if they wanted to grow bigger, they 0:32:21.880 --> 0:32:25.520 had to molt, which meant discarding that protective outer layer. 0:32:25.560 --> 0:32:29.720 And temporarily risking a soft bodied existence in order to 0:32:29.760 --> 0:32:32.880 grow that larger, harder shell. It would be like if 0:32:32.880 --> 0:32:37.560 there were a prehistoric hominid creature that left multiple skeletons, 0:32:37.880 --> 0:32:40.080 you know, which is of course impossible, but with an 0:32:40.080 --> 0:32:43.840 exoskeleton is is completely is very possible. Well, the vulnerability 0:32:43.840 --> 0:32:46.240 of molting makes me think about the comparison to a 0:32:46.320 --> 0:32:48.719 human newborn. You know, when when babies are born, they 0:32:48.760 --> 0:32:53.040 don't necessarily have all their their hard protective skeletal parts yet, 0:32:53.040 --> 0:32:56.760 and I have a lot of unfused together the unfused 0:32:56.800 --> 0:33:00.520 skull for example, and the soft cartilaginous body arts where 0:33:00.560 --> 0:33:05.200 you really do make yourself vulnerable when you're firstborn. But 0:33:05.280 --> 0:33:07.360 of course they're depending on the fact that mammals have 0:33:07.440 --> 0:33:10.000 protective parents that will try to prevent injury to their 0:33:10.040 --> 0:33:13.120 offspring when they're young and vulnerable trialo bites. I don't 0:33:13.160 --> 0:33:15.240 know if they're they're quite so protective of they're young. 0:33:16.120 --> 0:33:17.800 I mean you could say that puberty is kind of 0:33:17.840 --> 0:33:20.920 a molten period where where where we tend to be 0:33:21.360 --> 0:33:24.360 soft and vulnerable, if not in if not in mentally, 0:33:24.440 --> 0:33:29.600 at least mentally. Yeah. Uh so that's interesting to think 0:33:29.640 --> 0:33:32.400 of the molten process having an impact on the sheer 0:33:32.560 --> 0:33:36.200 number of fossilized remains. But but then on top of that, 0:33:36.240 --> 0:33:39.440 of course, it makes you analyze, and we've discussed this 0:33:39.520 --> 0:33:42.920 on the show before, like what makes a creature more 0:33:43.200 --> 0:33:47.000 liable to be fossilized? And I mean, you look at 0:33:47.040 --> 0:33:49.720 the creatures that are fossilized in any great number. It's 0:33:49.720 --> 0:33:51.720 not going to be an apex predator living in a 0:33:51.800 --> 0:33:54.360 dry region. It's going to be something like a low 0:33:54.440 --> 0:33:57.040 level and burd invertebrate that lives in the muck. Yea 0:33:57.280 --> 0:34:01.320 something that gets buried quickly. Uh, and that leaves behind 0:34:01.400 --> 0:34:04.800 hard body parts near water, especially right. So the great 0:34:04.920 --> 0:34:08.240 the Great Land squid of old rights have not been preserved, 0:34:09.239 --> 0:34:12.279 but their beaks are many. Oh yes, that's right. We 0:34:12.320 --> 0:34:14.799 would get the beaks, yeah, these beds of beaks, and 0:34:14.840 --> 0:34:18.040 we'd wonder what they are. Yeah. But because there are 0:34:18.080 --> 0:34:21.120 so many trialobite fossils, and because they're so strange and 0:34:21.160 --> 0:34:24.200 so alien to the modern life forms we encounter in 0:34:24.239 --> 0:34:25.920 our day to day lives, I mean, they might be 0:34:25.960 --> 0:34:28.960 they might bear some resemblance to insects for example. Right, 0:34:28.960 --> 0:34:32.560 And this is why railroad worker might call them stone bugs, 0:34:32.840 --> 0:34:34.640 but it's no surprise that they show up in human 0:34:34.640 --> 0:34:37.120 culture too. I wanted to mention one cool example I 0:34:37.120 --> 0:34:40.880 came across. Remember Adrian Mayor who wrote the first Fossil Hunters. 0:34:40.880 --> 0:34:43.400 We talked about her in our in our what was 0:34:43.440 --> 0:34:46.799 it the geomethology? Yes, yes, this we had to do 0:34:46.880 --> 0:34:50.800 with how did ancient people look at fossilized remains, didn't 0:34:50.880 --> 0:34:54.200 think they were monsters? That they think they were dragons? Yeah? Yeah? 0:34:54.200 --> 0:34:57.360 And did did these ideas of mythical monsters come from 0:34:57.520 --> 0:35:01.280 people finding fossils? So she's got another boat called Fossil 0:35:01.360 --> 0:35:04.040 Legends of the First Americans, and she writes of how 0:35:04.160 --> 0:35:07.640 trio bite fossils were apparently used as protective amulets by 0:35:07.680 --> 0:35:10.839 some of the Ute people of Utah. So this one 0:35:10.880 --> 0:35:13.160 story is in the early nineteen hundreds, there was an 0:35:13.160 --> 0:35:17.160 amateur natural historian named Frank Beckwith and he noticed a 0:35:17.200 --> 0:35:20.080 trio bite necklace at a Ute burial site. So he 0:35:20.120 --> 0:35:23.000 asked some friends of his name, Joseph and Tedford pick 0:35:23.120 --> 0:35:26.240 of It, who were members of the tribe, what this meant, 0:35:26.400 --> 0:35:29.080 and they told him that the fossil was called timpei 0:35:29.200 --> 0:35:34.279 kanitsa Pavacci which meant little water bug in Stone and 0:35:34.440 --> 0:35:37.080 Beckwith also records that the men told him that their 0:35:37.080 --> 0:35:40.200 elders believed that wearing the trio bites could protect against 0:35:40.239 --> 0:35:43.560 sickness and bullets. But I thought that's kind of cool that. 0:35:43.920 --> 0:35:47.480 Look somehow the fossils were intuited to have been water 0:35:47.560 --> 0:35:51.040 dwelling creatures, and I wonder how people would have figured 0:35:51.080 --> 0:35:54.160 that out back then. I thought that was really interesting. Yeah, 0:35:54.239 --> 0:35:56.640 especially given that there would be there would be plenty 0:35:56.640 --> 0:35:59.759 of terrestrial invertebrates to compare it to. I guess maybe 0:35:59.760 --> 0:36:03.880 they maybe they saw more of the of the crab 0:36:04.080 --> 0:36:07.440 in this creature than they did, uh, you know, terrestrial bucks. 0:36:07.760 --> 0:36:09.560 I know, I wouldn't have been that perceptive. I would 0:36:09.600 --> 0:36:13.600 have called it like roly Poly or something. Well, anyway, 0:36:14.000 --> 0:36:16.600 considering that all these there are all these shells everywhere, 0:36:17.440 --> 0:36:20.360 another possible answer to the question of what caused the 0:36:20.360 --> 0:36:25.080 Cambrian explosion comes up. What if the Cambrian explosion is 0:36:25.080 --> 0:36:28.480 an illusion? What if it is not so much an 0:36:28.480 --> 0:36:31.880 event in history where all these animals suddenly emerged, but 0:36:32.000 --> 0:36:36.680 a misperception created by the types of evidence available to us. 0:36:37.200 --> 0:36:39.320 So this would be like a reporting error exactly. It 0:36:39.320 --> 0:36:42.279 would be a sampling bias. How would that be. Well, 0:36:42.600 --> 0:36:45.080 like we've been talking about, we know fossilization has this 0:36:45.200 --> 0:36:48.960 serious preference for hard body parts, and it appears to 0:36:49.040 --> 0:36:53.000 be around the Cambrian period that biomineralization, right, the forming 0:36:53.080 --> 0:36:56.400 of these mineral based body parts like skeletons and shells, 0:36:56.840 --> 0:36:59.560 that that became common in many different animals. It's the 0:36:59.600 --> 0:37:03.319 age of shells and exoskeletons. So it could be that 0:37:03.440 --> 0:37:08.200 many animal forms had precedent in the Precambrian era, that 0:37:08.239 --> 0:37:11.480 there were there were animals sort of like them living before, 0:37:11.880 --> 0:37:14.279 and it's simply that we don't have good records of 0:37:14.280 --> 0:37:18.200 them because they weren't making hard body parts yet. Okay, 0:37:18.360 --> 0:37:20.200 so this makes sense. So it's not it's it's not 0:37:20.239 --> 0:37:22.480 that just suddenly there are all these creatures around with 0:37:22.520 --> 0:37:25.120 their hard shells. There were plenty of creatures around beforehand. 0:37:25.160 --> 0:37:27.600 It's just those were not preserved. Those are not as 0:37:27.600 --> 0:37:29.920 president the fossil record, right, because they didn't have the 0:37:29.960 --> 0:37:34.320 hard shells. Yeah. On the other hand, even soft animals 0:37:34.400 --> 0:37:40.200 leave some fossil traces like tracks and burrows, and generally, 0:37:40.239 --> 0:37:43.320 I think paleontol just think that these types of fossils 0:37:43.320 --> 0:37:45.680 are not as abundant as they would seem to be 0:37:46.280 --> 0:37:49.840 if the Precambrian world was basically a soft flappy copy 0:37:49.920 --> 0:37:52.520 of the Cambrian But either way, this leads us to 0:37:52.600 --> 0:37:54.880 a kind of new way of framing the Cambrian question. 0:37:54.920 --> 0:37:58.680 If the Cambrian explosion is characterized as this explosion of 0:37:58.760 --> 0:38:02.000 animal body plans, and especially those with hard body parts, 0:38:02.680 --> 0:38:05.360 why do the hard body parts show up? Like? Where 0:38:05.360 --> 0:38:08.560 do they come from? Why evolve shells? And this leads 0:38:08.640 --> 0:38:11.880 us to another possible answer to the to the cause 0:38:11.920 --> 0:38:14.759 of the Cambrian explosion. What if it was caused by 0:38:14.800 --> 0:38:19.759 a biological innovation like predation? Oh so like you, So 0:38:19.840 --> 0:38:22.120 you have all of these creatures that have that have 0:38:22.200 --> 0:38:25.319 evolved and then suddenly they realize, Hey, we can just 0:38:25.320 --> 0:38:27.879 eat each other. I can I can just eat these guys. 0:38:27.920 --> 0:38:31.120 Why should I compete for the same same meal when 0:38:31.160 --> 0:38:33.480 I can make them my meal and then I'm essentially 0:38:33.480 --> 0:38:36.600 eating what they already ate, Right? Why would I waste 0:38:36.600 --> 0:38:39.240 my time filter feeding when I can just eat ted 0:38:39.320 --> 0:38:44.359 over there? Yeah? So Eric Sperling, the Stanford paleontologist who 0:38:44.400 --> 0:38:46.400 is the lead author on one of the papers I 0:38:46.400 --> 0:38:48.920 mentioned earlier in this episode, he explained in a Nature 0:38:48.960 --> 0:38:52.120 News article earlier this year, or actually know it was 0:38:52.200 --> 0:38:56.000 last year, that he thinks a very modest increase in 0:38:56.080 --> 0:39:01.200 dissolved oxygen could have been enough to push the the 0:39:01.320 --> 0:39:04.879 ocean chemistry over the edge to allow for the emergence 0:39:04.920 --> 0:39:09.880 of predation and carnivory as an ecological niche, which would 0:39:09.880 --> 0:39:13.880 have thereafter driven evolution across the animal spectrum as this 0:39:14.080 --> 0:39:17.520 arms race between predator and prey emerged. In a world 0:39:17.520 --> 0:39:20.160 of predators, you need shells and you need to be 0:39:20.200 --> 0:39:24.840 able to move. Yeah, alright, well, this this sounds the 0:39:24.880 --> 0:39:27.920 sounds plausible, and there's some evidence that this is what 0:39:28.040 --> 0:39:32.359 was happening. Here's an odd fact. Sometimes trialobyte fossils are 0:39:32.480 --> 0:39:36.480 missing chunks, not because the fossils have been damaged, but 0:39:36.520 --> 0:39:40.600 apparently because the animals were One example, a specimen of 0:39:40.640 --> 0:39:44.480 the trial trialobyte illinoid is found in Walcott's Quarry at 0:39:44.480 --> 0:39:48.320 the Burge of Shale, has this distinct W shape missing 0:39:48.400 --> 0:39:51.040 from its left side, as if something took this kind 0:39:51.040 --> 0:39:53.920 of two fanged bite out of it. So in this 0:39:54.000 --> 0:39:57.239 alien ocean, and you have to imagine me uh in 0:39:57.320 --> 0:40:00.560 the voice of ripley and aliens whose laying the eggs, 0:40:01.239 --> 0:40:05.520 what's taking the bites out of these trilobites. Maybe it's 0:40:05.600 --> 0:40:09.200 less dramatic if if you put it that way, but 0:40:09.200 --> 0:40:11.560 but yeah, there's gotta be something something else out there, 0:40:11.640 --> 0:40:15.040 some sort of predator that is that is chomping down 0:40:15.040 --> 0:40:17.600 on these guys. And this leads us to the second 0:40:17.640 --> 0:40:22.279 monster in our Cambrian monster house, the weird shrimp. All right, 0:40:22.360 --> 0:40:24.120 hold that thought, because we're gonna take a quick break, 0:40:24.160 --> 0:40:26.359 and when we come back, we will we will get 0:40:26.400 --> 0:40:29.359 to know the weird shrimp, which is truly unless you're 0:40:29.360 --> 0:40:32.200 already you know, super familiar with this time period, I 0:40:32.200 --> 0:40:35.960 would say it's the first really alien creature of the 0:40:36.239 --> 0:40:44.080 Cambrian period. Alright, we're back, Okay. So in a British 0:40:44.160 --> 0:40:48.719 Canadian paleontologist named Joseph Frederick Witty Eves was trying to 0:40:48.719 --> 0:40:52.799 figure out how to classify some odd Cambrian fossils that 0:40:52.920 --> 0:40:58.280 looked like headless shrimp shells. You can look at pictures 0:40:58.280 --> 0:41:01.279 of these online, but um, you could see these five 0:41:01.360 --> 0:41:05.960 hundred million year old imprints of these clawed tails and bodies, 0:41:06.360 --> 0:41:08.759 but the heads were always missing. Yeah, they look kind 0:41:08.760 --> 0:41:11.759 of They basically looked like entrees. Yeah. Yeah, it's like 0:41:11.840 --> 0:41:14.200 somebody pulled the head off the shrimp and served it 0:41:14.239 --> 0:41:17.600 to you in a little cocktail glass. Now. He named 0:41:17.640 --> 0:41:22.680 the organism Anomala carus, which means weird shrimp or strange 0:41:22.719 --> 0:41:27.760 shrimp or odd shrimp, however you prefer. Meanwhile, Burgess Shale 0:41:27.800 --> 0:41:30.560 pioneer Charles Walcott, which who is the guy who the 0:41:30.560 --> 0:41:33.520 Walcott's Quarry at the Burgess Shield was named after, he 0:41:33.680 --> 0:41:37.240 collected and described a fossil of a different animal. These 0:41:37.280 --> 0:41:42.400 preserved remains only showed a large, disembodied mouth, a thick, 0:41:42.600 --> 0:41:46.840 muscular ring shape surrounded by a circle of jagged teeth 0:41:46.960 --> 0:41:50.000 facing inward. And Walcott believed this mouth to be the 0:41:50.040 --> 0:41:53.440 remains of a jelly fish that he named Patoya. All right, 0:41:53.480 --> 0:41:56.400 so this would be the mouth of an otherwise soft creature, 0:41:56.520 --> 0:41:58.640 that was his argument. And all we have left is 0:41:58.680 --> 0:42:02.279 the mouth, right. And it wasn't until many decades later 0:42:02.280 --> 0:42:05.799 that researchers Harry Whittington and Derek Briggs figured out that 0:42:05.840 --> 0:42:10.000 these two weird anomalous animals were weird and anomalous because 0:42:10.040 --> 0:42:14.040 they were different parts of the same creature. A huge 0:42:14.320 --> 0:42:18.360 Cambrian predator that retained the name of Anomala carus. The 0:42:18.440 --> 0:42:23.320 weird shrimp were actually a pair of clawed appendages basically 0:42:23.600 --> 0:42:27.480 mouth tentacles for snatching up prey and shoving it into 0:42:27.560 --> 0:42:31.000 the mouth parts, and the mouth parts were the toothy ring, 0:42:31.120 --> 0:42:34.919 which had previously been identified as patoya. If you've never 0:42:34.960 --> 0:42:37.319 seen an image of Anomala cars this is another thing 0:42:37.360 --> 0:42:39.400 to look up, well, or maybe we'll try to include 0:42:39.400 --> 0:42:42.280 a picture on the landing. Yeah, we'll include a picture 0:42:42.280 --> 0:42:44.680 of this this creature because it's just too it's too weird. 0:42:44.719 --> 0:42:48.160 If if need be, we will draw one and uploaded 0:42:48.200 --> 0:42:50.560 to the side. It's sort of like impossible to make 0:42:50.600 --> 0:42:54.440 yourself believe that this thing really existed on Earth. But 0:42:54.520 --> 0:42:58.120 I've seen the fossils now, and so the reason these 0:42:58.160 --> 0:43:02.120 disembodied parts were originally is identified was a common problem 0:43:02.160 --> 0:43:05.600 in paleontology. As we've mentioned several times now, fossilization is 0:43:05.600 --> 0:43:09.560 strongly biased toward hard body parts like shells and bones. 0:43:09.960 --> 0:43:14.000 Anomala Carus did not have a hard exoskeleton covering its 0:43:14.000 --> 0:43:17.160 whole body, but probably had a very light, kitanous outer 0:43:17.280 --> 0:43:20.360 layer like a shrimp shell. On some parts of its body, 0:43:20.760 --> 0:43:24.000 and when it died and decomposed, its body probably fell 0:43:24.080 --> 0:43:27.480 apart into different pieces, and not all of those pieces 0:43:27.760 --> 0:43:31.160 were preserved at the same rate. So it's rare to 0:43:31.160 --> 0:43:34.920 find fossils that preserve any information about soft body parts, 0:43:34.960 --> 0:43:38.000 and even rarer still to find soft bodies intact, all 0:43:38.000 --> 0:43:42.040 in one place. Rare, but not entirely impossible, because since 0:43:42.080 --> 0:43:46.040 the original discovery of what amounted to Anomala cars is 0:43:46.120 --> 0:43:51.239 killing equipment, more fully preserved Anomala Carus specimens have been discovered. 0:43:51.360 --> 0:43:55.080 For example, one fossil discovered in nineteen two shows the 0:43:55.239 --> 0:43:59.400 spiked feeding arms branching off of the head within reach 0:43:59.440 --> 0:44:02.359 of the shing mouth ring, and all contained within the 0:44:02.400 --> 0:44:07.040 imprint of this elongated soft body lined with lateral lobes 0:44:07.080 --> 0:44:10.600 that probably undulated to power swimming. So if you're trying 0:44:10.640 --> 0:44:13.040 to imagine this thing right now, you have to picture 0:44:13.080 --> 0:44:19.720 a kind of wide, flat lobed jellyfish snake undulating along 0:44:19.800 --> 0:44:23.200 through the ancient seas, with a gaping mouth ring on 0:44:23.239 --> 0:44:27.240 the underside that could squeeze with teeth but never fully close, 0:44:27.880 --> 0:44:30.160 and then sticking out of its face a couple of 0:44:30.200 --> 0:44:34.600 hooked fang tentacles lined with spikes. Yeah, this this looks 0:44:34.640 --> 0:44:38.520 like a creature that belongs in a Star Wars Cantina. Yeah. Yeah, 0:44:38.560 --> 0:44:40.600 it should be like having a drink and telling you 0:44:40.680 --> 0:44:44.120 it doesn't like you, and it probably doesn't like you. 0:44:44.440 --> 0:44:47.000 Now you're you might be thinking, okay, so how big 0:44:47.040 --> 0:44:50.240 were these things? Right? Like? A few inches long? Parts 0:44:50.280 --> 0:44:54.040 found in fossil sites in China indicate that Anomalocarras type 0:44:54.160 --> 0:44:57.839 organisms may have grown to almost two meters long, which 0:44:57.880 --> 0:45:01.880 is around six feet. You know, people do those like 0:45:01.920 --> 0:45:04.959 booking a swim with the dolphins thing. I think people 0:45:05.000 --> 0:45:07.440 should book swim with the anomal of carrass. They should 0:45:07.520 --> 0:45:10.520 use some kind of DNA engineering to bring these things 0:45:10.600 --> 0:45:12.840 back well you know, and then have you swim with 0:45:12.920 --> 0:45:16.040 them at the resort. Well, you know, the predation explosion 0:45:16.880 --> 0:45:20.600 hypothesis is correct, especially, I mean, this was eating other 0:45:20.640 --> 0:45:23.279 animals was a growth industry, so it it does make 0:45:23.360 --> 0:45:26.959 sense that that the the successful model for eating other 0:45:27.040 --> 0:45:31.319 creatures would produce larger and larger organisms, right. Yeah. So, 0:45:31.560 --> 0:45:33.520 but the question I guess is if these things are 0:45:33.600 --> 0:45:36.960 preying on the you know, the widespread trilobites of the 0:45:36.960 --> 0:45:39.560 ancient seas, I don't know, would they take a bite 0:45:39.600 --> 0:45:41.960 out of you if they could. So you're in the 0:45:41.960 --> 0:45:44.720 water with them, you do obviously don't look or smell 0:45:44.800 --> 0:45:47.759 like their normal prey, but then again, they might just 0:45:47.800 --> 0:45:50.120 want to see what you taste like. It's hard to know. 0:45:50.280 --> 0:45:54.200 We kind of get into that whole shark and gorilla area. 0:45:54.360 --> 0:45:56.600 I don't know if I've mentioned this on the podcast, 0:45:56.680 --> 0:45:58.400 but I don't think so. Well, every time I go 0:45:58.440 --> 0:46:02.640 to the ocean, I comfort my self regarding the risk 0:46:02.719 --> 0:46:04.840 or apparent risk of sharks and and of course just 0:46:04.920 --> 0:46:08.239 shark media in general by thinking about the just like 0:46:08.280 --> 0:46:10.760 a brief clip on The Simpsons where a shark jumps 0:46:10.760 --> 0:46:13.200 out of the water and grabs a gorilla out of 0:46:13.200 --> 0:46:17.400 a tree, which is ridiculous for several reasons, but it 0:46:17.719 --> 0:46:20.439 drives home like this is this is something that does 0:46:20.520 --> 0:46:25.359 not happen. Is not part of the the the the 0:46:25.360 --> 0:46:28.920 the energy model for either species, you know. Uh, And 0:46:29.080 --> 0:46:31.160 and that's essentially what I am. I am a gorilla 0:46:31.200 --> 0:46:34.040 in the water, and the shark has not evolved to 0:46:34.239 --> 0:46:37.120 eat me exclusively. It can if need be, but it's 0:46:37.160 --> 0:46:40.080 not out there looking for gorillas, right. It might have also, though, 0:46:40.160 --> 0:46:43.799 evolved a sort of like prey diversity, curiosity, it might 0:46:43.880 --> 0:46:47.040 take a little nibble on you to see what you're like, right, right, 0:46:47.160 --> 0:46:49.759 So I guess that would be the main concern. But 0:46:49.800 --> 0:46:52.800 I'm guessing you would have this element of surprise because 0:46:52.840 --> 0:46:54.600 by the way, I don't mean to be promoting like 0:46:54.680 --> 0:46:58.640 fear of sharks. We're not their primary prey, right, But 0:46:58.640 --> 0:47:01.400 but I'm guessing with with h means, if if we 0:47:01.400 --> 0:47:03.799 were to go with our opening scenario and you were 0:47:03.840 --> 0:47:06.839 just dropped into the waters among these things, I would 0:47:06.840 --> 0:47:10.399 hope you would have this this element of surprise over them, 0:47:10.400 --> 0:47:13.080 and they would be a bit shocked and uncertain and 0:47:13.160 --> 0:47:16.439 hesitant to approach you. So another thing that's really cool 0:47:16.440 --> 0:47:20.640 about Anomala carras is that they have these amazing eyes. 0:47:21.560 --> 0:47:25.480 For a long time, detailed evidence of non biomineralized arthropod 0:47:25.520 --> 0:47:28.080 eyes had been hard to find. But in two thousand 0:47:28.160 --> 0:47:30.520 eleven there was a letter to Nature that detailed this 0:47:30.600 --> 0:47:34.120 amazing find at the Emu Bay Shale of South Australia, 0:47:34.480 --> 0:47:38.200 and what they had found was preserved Anomala carus eyes, 0:47:38.719 --> 0:47:40.399 and they found that they had a pair of two 0:47:40.440 --> 0:47:44.160 to three centimeter eyes about five fifteen million years old, 0:47:44.920 --> 0:47:47.759 and they were compound eyes made of at least sixteen 0:47:47.760 --> 0:47:51.759 thousand hexagonally packed lenses, meaning these eyes would have been 0:47:52.080 --> 0:47:55.960 about as acute as the most powerful arthropod eyes today, 0:47:56.000 --> 0:47:59.799 like dragonfly eyes. And the authors think that this is 0:48:00.239 --> 0:48:02.920 that this evidence of acute vision lends support to the 0:48:02.960 --> 0:48:06.560 idea that anomal a caress was a powerful, fast moving 0:48:06.640 --> 0:48:10.560 apex predator going all throughout the water column, which and 0:48:10.719 --> 0:48:14.000 this would have accelerated the arms race that triggered Cambrian 0:48:14.040 --> 0:48:18.640 biodiversity and biomineralization. You know this also this makes me wonder, though, 0:48:19.239 --> 0:48:22.560 would a creature like this have anything to fear? Well, 0:48:22.600 --> 0:48:24.680 I mean probably not. I mean, if it's the apex 0:48:24.719 --> 0:48:27.480 predator of an ancient ocean, what, it's the biggest thing 0:48:27.480 --> 0:48:30.080 out there and it's got the most powerful killing equipment. 0:48:30.360 --> 0:48:33.000 What does it have to worry about? Nothing? Until you know, 0:48:33.040 --> 0:48:36.080 the time traveling human shows up and starts clubbing them. 0:48:36.120 --> 0:48:38.000 I guess that club they brought. You'd have to bring 0:48:38.000 --> 0:48:40.680 your own club. That's the key here. But nothing dead 0:48:40.680 --> 0:48:45.080 will go. Ah, well, you know, maybe a still living 0:48:45.120 --> 0:48:48.720 tree branch will work. Oh yeah, maybe that. Somebody should 0:48:48.719 --> 0:48:51.000 have told kyleys about that. I guess that wouldn't have 0:48:51.000 --> 0:48:53.080 been all that effective against the determinator. Yeah, where are 0:48:53.120 --> 0:48:56.000 they going to get a tree branch and the desolate 0:48:56.000 --> 0:48:59.880 post apocalypse future. Okay, we're on a tangent here, so 0:49:00.239 --> 0:49:03.480 we're gonna look at some more uh Cambrian monsters. But 0:49:03.640 --> 0:49:05.920 one more thing about anomally carriss before we move on. 0:49:06.239 --> 0:49:09.040 There is still a fascinating debate going on about how 0:49:09.160 --> 0:49:12.480 and what Anomala carress ate. So some of these wounded 0:49:12.520 --> 0:49:15.560 trial bytes that we discussed earlier have injuries that really 0:49:15.600 --> 0:49:19.680 seemed to match the two pronged grasping appendages of the 0:49:19.719 --> 0:49:23.520 anomal carrass and some experts believe that its mouthparts would 0:49:23.560 --> 0:49:27.080 not have been powerful enough to prey upon trial bytes 0:49:27.120 --> 0:49:29.840 with their hard outer shells. So that kind of creates 0:49:29.840 --> 0:49:34.080 a question like what was was it eating something else? 0:49:34.640 --> 0:49:37.520 Like how could it have gotten through these hard outer shells? 0:49:37.880 --> 0:49:40.319 There are a few options. Maybe maybe they were just 0:49:40.480 --> 0:49:44.040 really beefy and they could crunch through those shells. Maybe 0:49:44.040 --> 0:49:46.960 they had some method of prying the shells off of 0:49:47.040 --> 0:49:50.360 weaker trialobytes and sucking up all the soft parts inside. 0:49:50.920 --> 0:49:53.799 Or there's also an interesting possibility I learned about from 0:49:53.840 --> 0:49:56.799 the guide on our hike, David. Maybe they took a 0:49:56.880 --> 0:50:00.160 tip from the crab shack down the shore and they 0:50:00.160 --> 0:50:03.360 sought out soft shells trial bytes who were in the 0:50:03.719 --> 0:50:07.040 process of molting. So you you release your hard shell, 0:50:07.400 --> 0:50:09.839 put that aside to be fossilized for people to find 0:50:09.880 --> 0:50:12.800 millions of years later, and then you stay soft for 0:50:12.880 --> 0:50:16.080 a little bit while you, you know, you grow. What 0:50:16.200 --> 0:50:19.160 if they sought those out, the molten trial bytes and 0:50:19.360 --> 0:50:22.279 nominomomb Oh man, Yeah, I mean that could be. That 0:50:22.320 --> 0:50:26.080 could be the very uh niche that they are exploiting. 0:50:26.320 --> 0:50:28.720 When you turn to the model of of of eating 0:50:28.719 --> 0:50:32.480 other creatures, what better time than the molting period. Yeah, okay, 0:50:32.520 --> 0:50:35.279 So the trial bytes and anomalo carras type creatures are 0:50:35.320 --> 0:50:39.080 some of the main players that we see in UH 0:50:39.120 --> 0:50:42.040 in Cambrian evolution, but there are also all of these 0:50:42.120 --> 0:50:47.759 fascinating bizarre periphery organisms. Like Robert, would you like to 0:50:47.800 --> 0:50:49.719 take us on a tour of the rest of the 0:50:49.719 --> 0:50:53.879 Cambrian monster house. Sure? Yeah, we have some wonderful UH 0:50:53.920 --> 0:50:57.440 specimens here to discuss here, and there's not there's not 0:50:57.480 --> 0:51:00.520 necessarily as much data behind all of them. I mean 0:51:00.560 --> 0:51:03.239 there's data, but it's maybe not as as sexy as 0:51:03.520 --> 0:51:08.680 a trilobyte. However, they still have some some fascinating features, 0:51:08.719 --> 0:51:11.320 and I think many of them would make excellent Halloween costomes. 0:51:11.360 --> 0:51:14.040 I would say they're much sexier than the trilobyte, maybe 0:51:14.080 --> 0:51:17.680 just not as a robust. So the first one here 0:51:17.719 --> 0:51:22.560 I want to discuss is um opabinia. I've often called 0:51:22.600 --> 0:51:26.920 the stock eyed vacuum cinabyte. That's a good description one 0:51:26.920 --> 0:51:30.280 that I think evokes the alien qualities of this creature. 0:51:30.400 --> 0:51:33.080 So if you're not looking at a picture of this 0:51:33.239 --> 0:51:35.000 right now and stuff to blow your mind dot com, 0:51:35.120 --> 0:51:37.600 I want you to imagine something like a shrimp orl lobster, 0:51:38.320 --> 0:51:42.200 but with rows of side lobes along its sides, paddling 0:51:42.239 --> 0:51:46.160 along like the ores of like a galley so spiking ship. 0:51:46.320 --> 0:51:48.360 You's got these lobes on the sides, kind of like 0:51:48.440 --> 0:51:51.480 we described with the nominal caras that undulate to move 0:51:51.480 --> 0:51:54.840 it along throughout the water. Right And you know, it 0:51:54.960 --> 0:51:56.960 is not that remarkable at the the end, Like I said, 0:51:56.960 --> 0:51:58.640 if you were just catching it a glimpse of it 0:51:58.640 --> 0:52:01.040 out of the corner of your eye, that the back 0:52:01.080 --> 0:52:03.840 portion doesn't look that different from again, like a lobster 0:52:03.960 --> 0:52:06.920 or shrimp or something. But it's the front end of 0:52:06.960 --> 0:52:10.239 the creature that is is rather interesting because it has 0:52:10.280 --> 0:52:15.520 a long, flexible proboscis tipped with grasping spines, and the 0:52:15.560 --> 0:52:18.359 creature itself was about three inches long, not counting this 0:52:18.520 --> 0:52:22.600 uh weird cool richie tentacle. Yeah, five eyes to right, 0:52:23.160 --> 0:52:26.960 five eyes on stalks, yes, five eyes just standing right 0:52:27.000 --> 0:52:31.640 at you on stalks like they put them on stalks. 0:52:31.960 --> 0:52:34.520 It's like just a mess with us. Yeah, and I 0:52:34.600 --> 0:52:36.840 think this all sounds very love crafty and but but 0:52:36.880 --> 0:52:40.640 according to the Smithsonian National Museum of Natural History, a 0:52:40.719 --> 0:52:44.920 reconstructed image of the creature resulted in laughter at a 0:52:45.000 --> 0:52:47.840 nine two scientific meetings. So instead of looking at this 0:52:47.920 --> 0:52:51.399 thing and thinking, oh, this sounds horrific, it's like, got 0:52:51.400 --> 0:52:53.360 this reaching arm that you know is up to no 0:52:53.480 --> 0:52:56.640 good with its spikes on the end. But yeah, apparently 0:52:56.680 --> 0:53:01.240 when it was first presented, uh, other other scientists laughed 0:53:01.280 --> 0:53:04.440 at the prospect of something this ridiculous looking. So you 0:53:04.480 --> 0:53:06.839 have to think, So, it's got this reaching appendage that's 0:53:06.840 --> 0:53:09.640 sort of like its mouth appendage thing, So what's sort 0:53:09.640 --> 0:53:13.000 of like maybe sort of like an ant eater, I guess, 0:53:13.040 --> 0:53:16.359 but it's obviously not a vertebrate, not a mammal. Yeah, 0:53:16.440 --> 0:53:18.880 it was. The idea here is that this would have 0:53:19.120 --> 0:53:21.440 haunted the soft seabed and it would have would have 0:53:21.480 --> 0:53:27.040 reached into sand burrows with this, So this spiked terminating 0:53:27.360 --> 0:53:32.400 wriggly arm to grab delicious worms and uh and actually 0:53:32.440 --> 0:53:35.439 have a quote here. This is from HB. Whittington from 0:53:35.960 --> 0:53:41.920 the enigmatic animal Opabinia regalis Middle Cambrian Burgess Shale, British Columbia. 0:53:41.960 --> 0:53:47.000 This was presented the Royal Society b quote. Opabinia regalius 0:53:47.040 --> 0:53:51.120 may have plowed shallowly in the bottom mud, propelled by 0:53:51.239 --> 0:53:54.480 movement of the lateral lobes. The eyes are presumed to 0:53:54.640 --> 0:53:57.880 have been capable of detecting movements in the surrounding waters, 0:53:58.200 --> 0:54:00.760 and the frontal process to have been is to explore 0:54:00.840 --> 0:54:03.560 the mud for food and bring it to the backward 0:54:03.600 --> 0:54:08.520 facing mouth. The frontal process that is the most amazing 0:54:08.600 --> 0:54:12.680 euphemistic term for killing equipment. And then they put the 0:54:12.680 --> 0:54:16.000 frontal process through the thorax the way that my son 0:54:16.280 --> 0:54:19.400 uh describes it with the animals when he's like drawing dinosaurs. 0:54:19.400 --> 0:54:21.440 He says that this is the part that makes the 0:54:21.440 --> 0:54:28.080 animal's eyes close and then die. Yeah, so you know, 0:54:28.080 --> 0:54:30.319 the frontal process is the part that makes the trial 0:54:30.400 --> 0:54:34.880 by its eyes closed. So this is this is the 0:54:34.920 --> 0:54:38.040 cool specimen. It's it's unique, it's enigmatic, it's silly looking, 0:54:38.120 --> 0:54:40.600 but it's also, you have to admit, a very sensible 0:54:40.719 --> 0:54:44.120 organism when you really think about it. Um, it's it 0:54:44.200 --> 0:54:46.640 needs something to grab those worms. It has a single 0:54:47.280 --> 0:54:51.480 you know, grabber to do it. Now, it's also interesting 0:54:51.520 --> 0:54:56.200 that this one remains unassigned to any other extinct or 0:54:56.360 --> 0:54:59.759 currently living major group. That there are some theories, but 0:54:59.800 --> 0:55:02.799 for most part, this is one of those um, you know, 0:55:02.840 --> 0:55:06.520 abandoned prototypes you can think of. You know, there's there's 0:55:06.560 --> 0:55:09.319 nothing out there that that we know of that is 0:55:09.360 --> 0:55:12.960 a descendant of this thing. That's interesting because when I 0:55:12.960 --> 0:55:15.919 think about organisms like this, I think about the relationship 0:55:16.000 --> 0:55:21.680 between manipulation limbs and the evolution of intelligence. I mean, 0:55:21.719 --> 0:55:25.799 there's one way of looking at the evolution of hominid intelligence, 0:55:26.040 --> 0:55:28.440 and it's to say that, Okay, one thing that may 0:55:28.480 --> 0:55:32.319 have driven humans and other you know, great apes to 0:55:32.360 --> 0:55:36.040 have larger brains and more intellectual power than the average 0:55:36.080 --> 0:55:39.399 mammal is that they've got free limbs that they don't 0:55:39.440 --> 0:55:42.200 always have to use for walking and stuff like that 0:55:42.440 --> 0:55:46.680 to manipulate objects, and that the manipulation of objects allowed 0:55:46.719 --> 0:55:49.920 them to, you know, have advantages in the manipulation of 0:55:50.000 --> 0:55:53.440 tools and stuff like that. Yeah, you can't help but 0:55:53.520 --> 0:55:56.640 imagine like what if this had been a successful uh 0:55:57.120 --> 0:56:00.640 limb of of of evolutionary ascension, and then it ended 0:56:00.760 --> 0:56:05.040 up with all of these different like monolimbed creatures, you know, 0:56:05.120 --> 0:56:07.640 plowing about in the seas, climbing up onto land and 0:56:07.680 --> 0:56:09.759 maybe getting to the point where they're using that that 0:56:09.920 --> 0:56:14.359 one spiky tentacle to to type on computer keyboards. Yeah, yeah, 0:56:14.440 --> 0:56:17.600 you see it in octopy to you know, having these free, 0:56:17.760 --> 0:56:20.440 these free limbs that they can manipulate things with. I 0:56:20.480 --> 0:56:23.960 wonder could opabinia if it hadn't gone extinct yet, could 0:56:23.960 --> 0:56:27.520 it have become the tool using creature before they were 0:56:27.520 --> 0:56:31.400 even mammals. But instead it just remains this this weird 0:56:31.440 --> 0:56:33.960 dead end that looks it looks like if you decided 0:56:34.000 --> 0:56:37.600 to make an animal out of random Lego pieces and 0:56:37.680 --> 0:56:39.840 you stuck that. I think they still have that that 0:56:39.880 --> 0:56:44.800 sort of twisty grabber mechanism and the Lego kids today. Alright, 0:56:44.880 --> 0:56:49.319 the next creature on our list. Here is the hallucigenia. 0:56:49.440 --> 0:56:53.520 Hallucigenia well named. Yeah, it almost doesn't need a cool nickname, 0:56:53.560 --> 0:56:55.600 but I know you have one thought up already. How 0:56:55.600 --> 0:57:01.120 about the creeping headless spike worm. Yes, yeah, that's because 0:57:02.000 --> 0:57:04.520 it works because we're essentially looking at a tube of 0:57:04.600 --> 0:57:08.640 flesh with two rows of spines on one side and 0:57:08.760 --> 0:57:13.400 one row of mouth tipped tentacles on the other, and 0:57:13.480 --> 0:57:17.000 on either end, if we're keep in mind here we're 0:57:17.000 --> 0:57:19.400 working from the fossils. Here on either end, there's kind 0:57:19.400 --> 0:57:22.680 of a dark stain. Presumably one of them is the head. 0:57:23.160 --> 0:57:25.840 And presumably the idea here is that, or at least 0:57:25.840 --> 0:57:28.200 the early ideas that it walked about on those spines 0:57:28.240 --> 0:57:31.680 and it waved its tentacles above it. Uh, so you 0:57:31.720 --> 0:57:36.480 had this still walking tentacle waiver something with no modern analogy, 0:57:37.480 --> 0:57:39.680 no modern analogy. It looks like something that you would 0:57:39.680 --> 0:57:44.760 see illustrated in a Wayne Barlow alien book, you know, Yeah, yeah, absolutely, 0:57:45.080 --> 0:57:48.160 or like something um, I don't know. It looks kind 0:57:48.160 --> 0:57:50.720 of like one of those blobs that sometimes shows up 0:57:50.720 --> 0:57:53.160 in a Gary Larson cartoon when he's just trying to 0:57:53.160 --> 0:57:55.560 create a weird alien shape. Yeah, I mean it looks 0:57:55.640 --> 0:57:57.720 like something that would come out of a dream, thus 0:57:57.720 --> 0:58:00.400 its name. You know, it looks it's hallucigen you it's 0:58:00.440 --> 0:58:03.480 something that is that that seems like a fever dream 0:58:03.800 --> 0:58:06.280 of brought to life in a fossil. Now. I think 0:58:06.400 --> 0:58:10.600 this was first first put together by paleontologists in the seventies, 0:58:10.680 --> 0:58:13.640 right right, and then they had there was a subsequent 0:58:13.800 --> 0:58:17.360 find from China that showed a similar creature with a 0:58:17.440 --> 0:58:21.760 second row of tentacles tipped with claws, and then they realized, oh, 0:58:21.920 --> 0:58:24.400 we have it upside down. The creature walked on the 0:58:24.440 --> 0:58:29.120 tentacles and the spikes provided an upward facing protective array. 0:58:29.400 --> 0:58:31.800 So that's a lot. I mean, it's still a weird 0:58:31.840 --> 0:58:34.000 looking critter, don't get me wrong, but that's a lot 0:58:34.040 --> 0:58:35.880 more in keeping us what we might expect. You know, 0:58:35.960 --> 0:58:39.080 that's not that different from say a turtle with legs 0:58:39.080 --> 0:58:42.000 on the bottom and the protective display on the top, 0:58:42.160 --> 0:58:45.560 or any you know, various examples from the invertebrate world. 0:58:45.720 --> 0:58:48.800 I don't know, is that less weird? I'm trying to think. Okay, 0:58:48.840 --> 0:58:51.920 so it's it's like a worm and it's got these 0:58:51.960 --> 0:58:54.880 long tentacles with mouths on them that it walks on. Yeah, 0:58:54.920 --> 0:58:58.320 I mean, it's still weird and it's got spikes sticking up. Okay, yeah, 0:58:58.320 --> 0:59:01.240 I guess a little less weirder than walking on the spikes. Yeah, 0:59:01.360 --> 0:59:03.760 I guess. It's kind of a fun experiment you can 0:59:03.760 --> 0:59:07.439 play anytime you see like a crazy alien illustration. Try 0:59:07.480 --> 0:59:09.760 to decide is it more alien if you turn it 0:59:09.840 --> 0:59:13.960 upside down? Uh? Because yeah, you can either improve upon 0:59:13.960 --> 0:59:16.000 the design or figure out how they came up with 0:59:16.000 --> 0:59:20.720 it to again with maybe. Alright, so let's talk about 0:59:20.720 --> 0:59:22.760 it a little bit bit more here. So, University of 0:59:22.800 --> 0:59:27.600 Durham invertebrate paleontologist Martin R. Smith, who is an interesting 0:59:27.640 --> 0:59:30.480 chap He has a nice online presence. He placed the 0:59:30.760 --> 0:59:33.840 fossil of one of these creatures in an electron microscope 0:59:33.840 --> 0:59:37.040 in an attempt to figure out more about it, and 0:59:37.200 --> 0:59:40.080 one of the pressing questions was name, like which which 0:59:40.160 --> 0:59:42.320 end is the head and which one is the anus? Well, yeah, 0:59:42.360 --> 0:59:44.240 I mean that that's sort of. I knew there was 0:59:44.280 --> 0:59:46.800 some problem with locating its head, and that comes through 0:59:46.800 --> 0:59:50.520 in my name nomenclature of it, the headless spike worm. Now, 0:59:50.600 --> 0:59:53.720 I mentioned the stains earlier, right like, basically from the fossils. 0:59:53.760 --> 0:59:55.280 We knew. We knew that there was like a big 0:59:55.320 --> 0:59:57.439 stain on one end and a smaller stain on the other, 0:59:57.520 --> 1:00:00.760 and one was presumably the head. So the larger stain 1:00:01.000 --> 1:00:03.560 was was for a long time interpreted as a balloon 1:00:03.760 --> 1:00:07.080 like head on this creature. But it turns out it 1:00:07.120 --> 1:00:10.040 was very much a stain. It was the quote, decay 1:00:10.160 --> 1:00:13.200 fluids that had been squeezed out of one end of 1:00:13.240 --> 1:00:15.880 the guts of the organisms. Yeah, so this was the 1:00:15.920 --> 1:00:19.040 anus and the head was on the other side. And 1:00:19.280 --> 1:00:21.000 when they looked to the head, you know what, they 1:00:21.040 --> 1:00:26.480 found hockey mask. Close they found a smiley face. Yeah, 1:00:26.560 --> 1:00:31.200 a pair of eyes with a semicircular grin. Uh. And 1:00:31.400 --> 1:00:33.120 so it was sort of like a they say, it 1:00:33.160 --> 1:00:35.920 was sort of like a caterpillar looking creature. Yeah. Now 1:00:35.920 --> 1:00:38.440 when I say smiley face, it's it's kind of abstract. 1:00:38.520 --> 1:00:40.840 I'm looking at an image of it here. But but 1:00:41.000 --> 1:00:43.800 we can't help but look at it with our with 1:00:43.800 --> 1:00:46.360 our human failings and say, oh, well that's a smiley face. 1:00:49.320 --> 1:00:53.160 Oh hallucigenia, you devil you. Yeah, so hallucigenia is a 1:00:53.160 --> 1:00:56.400 fun one for sure. Stealing my heart, take me somewhere, 1:00:56.400 --> 1:00:59.080 even weirder Robert, all right, well, the next one is 1:00:59.440 --> 1:01:03.080 will Whack see a Boy? And uh, I believe you? 1:01:03.320 --> 1:01:04.560 Did you? Did you come up with a name for 1:01:04.600 --> 1:01:07.840 this one or did I? Okay, I think I actually 1:01:07.960 --> 1:01:09.720 came up with a few different ones here. So it 1:01:09.760 --> 1:01:13.040 looks kind of like a prehistoric iron maiden. It also 1:01:13.120 --> 1:01:16.640 looks like an organic battle him or perhaps a grim 1:01:16.760 --> 1:01:22.120 dark Pokemon, and it provides another splash of of the 1:01:22.120 --> 1:01:26.520 bizarre to the Cambrian seas. So two rows of long 1:01:26.640 --> 1:01:30.920 spines and a kind of plate mail armor of leaf 1:01:31.000 --> 1:01:34.720 shaped ribbed plates again on something that looks like a hat. 1:01:35.160 --> 1:01:38.560 It it looks like a spiked hat like plate mail 1:01:38.680 --> 1:01:42.160 kind of scenario. I can't stress the armor analogy enough. 1:01:42.400 --> 1:01:44.840 It's kind of like a half of a walnut with 1:01:44.840 --> 1:01:48.080 with plate mail on it and knives sticking out. Yeah, 1:01:48.160 --> 1:01:50.439 it looks like something an orc would wear on its head. 1:01:52.800 --> 1:01:55.680 And uh, A lot of the fossils here are essentially 1:01:55.720 --> 1:01:58.200 that we have of this thing are essentially flattened remains 1:01:58.240 --> 1:02:01.240 of this natural armor. Again, it's the hard parts that 1:02:01.280 --> 1:02:03.960 were left with and we just have to try and 1:02:04.000 --> 1:02:07.040 interpret what the soft tissue would have consisted of. And 1:02:07.080 --> 1:02:09.960 there are different interpretations here. Now, Martin Smith, who I 1:02:10.080 --> 1:02:14.360 just mentioned earlier, he favors the mollus interpretation. He says 1:02:14.360 --> 1:02:17.800 that their mouths, which would have been a radula bearing 1:02:17.840 --> 1:02:20.840 two rows of teeth, have several similarities with the teeth 1:02:20.880 --> 1:02:24.080 of modern mollus and uh and then they look nothing 1:02:24.120 --> 1:02:27.160 like worm teeth. Because that's the other argument is that 1:02:27.200 --> 1:02:32.760 these are essentially worm creatures. Specifically they would be bristle worms. 1:02:32.800 --> 1:02:38.160 But that's more of a controversial interpretation. So there's not 1:02:38.240 --> 1:02:40.520 a lot of depth for that particular organism other than 1:02:40.560 --> 1:02:43.480 it just looks really strange. And when you when you 1:02:43.560 --> 1:02:47.520 see illustrations of the Cambrian Sea, you will often find 1:02:47.520 --> 1:02:49.160 it will get will get in there somewhere. It won't 1:02:49.200 --> 1:02:52.360 be the central organism, but it will it will have 1:02:52.400 --> 1:02:56.280 a place in the in the in the illustration. Now 1:02:56.280 --> 1:03:00.440 I've got a question round, Yes, among this ancient Embrillan 1:03:00.760 --> 1:03:04.240 monster house, this sea full of bizarre alien creatures, we 1:03:04.320 --> 1:03:08.520 have to imagine that modern day life forms can trace 1:03:08.600 --> 1:03:13.320 their roots back to organisms that inhabited these oceans, especially 1:03:13.600 --> 1:03:18.040 when you think about very successful modern philo like vertebrates. Yeah, 1:03:18.120 --> 1:03:20.880 because the whole idea here is not that like everything 1:03:20.960 --> 1:03:24.960 dies often and life begins a new Uh, that some 1:03:25.040 --> 1:03:29.240 of these models would would have descendants alive today, I'll 1:03:29.240 --> 1:03:33.440 be rather different to organisms, and we have just such 1:03:33.480 --> 1:03:37.360 a case with Pecaia. Though it's a controversial example, right, Yes, Yeah, 1:03:37.400 --> 1:03:40.200 that this is not this is not set in stone 1:03:40.640 --> 1:03:44.000 that the fossils, of course are. Yeah. You you referred 1:03:44.000 --> 1:03:49.200 to this as the ancestor fish slug or potential potential ancestor. 1:03:49.840 --> 1:03:52.360 So if you're not looking at an image of this creature, 1:03:52.440 --> 1:03:56.720 imagine a sea slug that swims like a modern fish, 1:03:56.800 --> 1:04:00.240 and you've got a clear vision of Pecaia, or at 1:04:00.320 --> 1:04:03.000 least its clear vision as anyone. The crazy thing about 1:04:03.040 --> 1:04:06.080 it is that that scientists point to its not a chord, 1:04:06.320 --> 1:04:09.080 a precursor to the spinal cord, and also a key 1:04:09.120 --> 1:04:12.360 aspect of this creature's swimming mechanics as a reason that 1:04:12.440 --> 1:04:16.360 it could just be an ancestor of all vertebrates, including humans. 1:04:17.160 --> 1:04:20.200 But we're also throwing a curve in all this because 1:04:20.240 --> 1:04:22.920 it has a two lobed head that doesn't sound like 1:04:22.920 --> 1:04:26.360 any vertebrates I've ever heard of. Yeah, scientists remain split 1:04:26.440 --> 1:04:30.680 on this. Now. A nineteen discovery of a primitive fish 1:04:30.720 --> 1:04:34.200 in the Lower Cambrian also suggests that it in Pekaia 1:04:34.440 --> 1:04:37.760 had an even more ancient common ancestor. Okay, so it 1:04:37.840 --> 1:04:41.200 might be that this thing wasn't a direct ancestor of 1:04:41.280 --> 1:04:44.360 existing vertebrates, but that it might have been an offshoot 1:04:44.440 --> 1:04:48.919 of whatever was a direct ancestor of living vertebrates. And 1:04:48.960 --> 1:04:50.880 I think it will make a great Halloween costume for 1:04:50.920 --> 1:04:54.120 anyone out there who's who's not sold on the previous specimens. 1:04:54.480 --> 1:04:56.880 Grandma fish slug. Yeah, yeah, I mean I can just 1:04:56.920 --> 1:05:00.120 imagine it moving like you get used to see ing 1:05:00.880 --> 1:05:04.200 footage of sea slugs and uh similar creatures and the 1:05:04.200 --> 1:05:06.200 way they move. But this would have moved if I'm 1:05:06.280 --> 1:05:09.200 if I'm reading it correctly, more more like a fish, 1:05:09.200 --> 1:05:12.240 more like an eel. So imagine like an eagle slug, 1:05:12.280 --> 1:05:15.120 and that's what you have here totally. Now there's one more. 1:05:15.240 --> 1:05:17.160 I I thought it would be good to mention because 1:05:17.160 --> 1:05:20.520 it's got a slightly love crafty and face, right leon 1:05:20.640 --> 1:05:24.680 Colia the Blind whip Hunter. Yes, it looks kind of 1:05:24.720 --> 1:05:27.000 it's this one's kind of hard to explain really, but 1:05:27.440 --> 1:05:30.200 you know, it looks shrimpy, looks a little flea like 1:05:30.920 --> 1:05:34.280 but imagine a blind monster that stumbles around in the 1:05:34.360 --> 1:05:38.800 murk just bull whipping everything in its vicinity with flails 1:05:38.880 --> 1:05:42.320 and then just really whipping the heck out of potential prey, 1:05:42.440 --> 1:05:45.360 so whips coming out of its face. Yes, and that's 1:05:45.360 --> 1:05:47.960 what we have with leon Colia. Now we assume it 1:05:48.040 --> 1:05:51.480 was blind because we haven't found evidence of I stalks yet, 1:05:51.880 --> 1:05:54.439 which if the thing, of course is that given these 1:05:54.440 --> 1:05:58.480 previous examples, it's entirely likely that that that could occur. 1:05:58.720 --> 1:06:02.040 At some point a future fossil find will reveal, oh, well, 1:06:02.080 --> 1:06:03.920 they did have eye structures and they look like this, 1:06:04.520 --> 1:06:07.720 but for the time being, the ideas that they were 1:06:07.840 --> 1:06:12.000 seemingly blind. The creature here was about two inches long, 1:06:12.360 --> 1:06:15.760 and it's usually classified as an as an arthropod, though 1:06:15.840 --> 1:06:21.600 sometimes it's thrown into the arachnomorph subgroups, which would connect it, 1:06:21.680 --> 1:06:26.080 you know, more to scorpions in trilobytes. But still it's 1:06:26.080 --> 1:06:28.760 a fascinating creature to try and imagine, especially in this 1:06:28.760 --> 1:06:33.000 this changing time where eyesight is coming online for various 1:06:33.080 --> 1:06:38.080 organisms and new new methods of exploiting other organisms are 1:06:38.120 --> 1:06:40.960 becoming possible, and this one is just whipping things with 1:06:41.000 --> 1:06:44.680 its face un fel it can eat something. Yeah, So 1:06:44.720 --> 1:06:47.000 I guess that's going to have to conclude our tour 1:06:47.360 --> 1:06:50.560 of the Cambrian monsters. But I do want to ask you, Robert. 1:06:50.600 --> 1:06:54.600 So clearly we have not exhausted all of the fascinating 1:06:54.680 --> 1:06:59.280 questions about the Cambrian period and the the emergence of biodiversity, 1:07:00.200 --> 1:07:04.600 animal biodiversity, especially in the Cambrian periods. So I want 1:07:04.600 --> 1:07:08.320 to ask you which of the Cambrian explosion theories we've 1:07:08.360 --> 1:07:11.000 discussed today appeals to you the most. Obviously we haven't 1:07:11.040 --> 1:07:14.400 covered all of the possibilities. There are other possible explanations 1:07:14.400 --> 1:07:17.760 out there. But what what what? What strikes true to you? Like? 1:07:17.840 --> 1:07:20.680 What sounds right? Does it? Could it have been site 1:07:21.080 --> 1:07:24.000 as the thing that triggered all of this biodiversity, or 1:07:24.080 --> 1:07:29.640 the innovation of predation and carnivary, or the chemistry for biomineralization, 1:07:30.400 --> 1:07:33.240 or is it just this sampling bias where you know, 1:07:33.320 --> 1:07:36.280 maybe that there isn't as much bio innovation in this 1:07:36.320 --> 1:07:38.840 period as it seems just from the fossil record. I mean, 1:07:38.840 --> 1:07:40.280 I guess I could play it safe and say a 1:07:40.320 --> 1:07:43.120 little bit of all of those, but but I guess 1:07:43.640 --> 1:07:48.200 I tend to buy more into the predation and and 1:07:48.360 --> 1:07:52.000 cite arguments with some support by by by some of 1:07:52.000 --> 1:07:53.960 the additional arguments. But but those are the two that 1:07:54.040 --> 1:07:56.960 I guess I feel like they have the most meat 1:07:57.360 --> 1:07:59.800 for me. But then again, I'm not a I'm not 1:07:59.840 --> 1:08:03.880 a a scientist, you know, specializing in this time period. 1:08:04.600 --> 1:08:05.800 But but those are the ones that I feel like 1:08:05.960 --> 1:08:08.040 the most. Maybe it's just calling to the five year 1:08:08.080 --> 1:08:11.760 old of me. It's the it's the explanation that involves 1:08:12.160 --> 1:08:14.960 creatures warring with each other and battling each other, and 1:08:15.040 --> 1:08:17.639 therefore that's the one that I can imagine. Yeah, it's 1:08:17.640 --> 1:08:20.000 hard to resist, now, I know, I've I think I 1:08:20.040 --> 1:08:23.440 read at some point that one of the arguments against 1:08:23.800 --> 1:08:27.920 the site hypothesis is just that site doesn't generally matter 1:08:28.640 --> 1:08:31.280 in the water, and especially in the deep water, as 1:08:31.360 --> 1:08:33.720 much as it does on land. And not that it 1:08:33.760 --> 1:08:36.360 doesn't matter at all, it does, but that you know, 1:08:36.439 --> 1:08:39.120 things like smell and hearing and stuff like that are 1:08:39.160 --> 1:08:41.559 more useful in the ocean. But yeah, I don't know, 1:08:41.800 --> 1:08:45.000 I'm not sure which I'm most convinced by. The predation 1:08:45.120 --> 1:08:49.280 one seems very interesting to me that if animals weren't 1:08:49.320 --> 1:08:54.360 really capitalizing on getting their energy from other more large 1:08:54.439 --> 1:08:57.400 sized animals before and suddenly they started doing that. That 1:08:57.400 --> 1:08:59.880 that could be you know, a game changer. It's also 1:09:00.040 --> 1:09:03.599 kind of an original sin type scenario too. It feels 1:09:03.680 --> 1:09:06.360 very mythic, right like that that the first creature to 1:09:06.400 --> 1:09:09.080 figure out that it can it can prey on its 1:09:09.160 --> 1:09:12.160 fellow organisms. And how does that occur? Like obviously it's 1:09:12.200 --> 1:09:15.880 it's not just a situation of one day, Uh this 1:09:16.120 --> 1:09:18.200 this creature just takes a bite out of another one 1:09:18.280 --> 1:09:21.639 Like it's going to be a more gradual process and uh, 1:09:21.680 --> 1:09:24.320 you know, and I'm likely begins with some sort of 1:09:24.400 --> 1:09:28.000 gray area of competition for food, like for instance, a 1:09:28.040 --> 1:09:32.160 creature it becomes adapt at stealing food from either maybe 1:09:32.200 --> 1:09:34.479 stealing food from its mouth, and what happens if you 1:09:34.520 --> 1:09:37.479 steal food from another creature's belly? Yeah, you know, I 1:09:37.520 --> 1:09:41.240 mean that That is the difficulty of this hypothesis is 1:09:41.280 --> 1:09:44.080 you have to imagine what's the process that gets you 1:09:44.120 --> 1:09:48.479 there by gradual evolutionary change, Even if it's geologically rapid, 1:09:48.479 --> 1:09:52.320 it still would have been gradual in biological terms. Um, 1:09:52.000 --> 1:09:55.040 trying to you know, go from an organism organisms that 1:09:55.080 --> 1:10:00.280 are all basically vegetarian to some organisms eating other animals. Yeah, yeah, 1:10:00.479 --> 1:10:02.360 Like another example that comes to mind, as of course, 1:10:02.400 --> 1:10:06.200 animals that will consume their own young or their own eggs. 1:10:06.640 --> 1:10:09.760 We've talked about, you know, the parental cannibalism to sort 1:10:09.760 --> 1:10:14.960 of re absorb essentially lost energy, and how that could 1:10:15.400 --> 1:10:19.919 seemingly be an avenue into the UH into inter predation, 1:10:20.280 --> 1:10:23.599 because if you're absorbing your own biomatter back into yourself, 1:10:23.840 --> 1:10:26.759 then it becomes a less of a leap to absorb 1:10:26.800 --> 1:10:29.640 the biomatter of another. I can also see a scavenging 1:10:29.720 --> 1:10:34.799 to predation route that maybe uh, the the gradual changes 1:10:34.880 --> 1:10:38.519 that allow you to better and better extracts nutrition from 1:10:38.720 --> 1:10:40.960 dead animals that you find on the bottom of the 1:10:40.960 --> 1:10:45.360 ocean could eventually become useful in killing live animals right right. 1:10:45.640 --> 1:10:48.360 Or you could just always do it and an angel 1:10:48.400 --> 1:10:52.400 told you not to until a snake suggested otherwise, just 1:10:52.520 --> 1:10:55.360 another possibility that could be it. Well, Robert, I don't 1:10:55.720 --> 1:10:57.479 I don't get the feeling that we're done with the 1:10:57.479 --> 1:10:59.680 Cambrian period. I think we may come back here in 1:10:59.680 --> 1:11:02.639 the few true to explore some other scientific issues and 1:11:02.640 --> 1:11:04.519 when there may be other things to discuss with the 1:11:04.520 --> 1:11:07.120 Burdge of Shale as well. Yeah, and uh, and in general, 1:11:07.160 --> 1:11:09.000 I'd love to do some more episodes in the future 1:11:09.960 --> 1:11:12.160 regarding prehistoric creatures. I feel like this is something we 1:11:12.439 --> 1:11:15.360 come back to time and time again, well at least 1:11:15.360 --> 1:11:19.439 on what a bi monthly uh kind of pattern, I guess. So, 1:11:19.520 --> 1:11:21.200 I mean it's it's the seven year old in me. 1:11:21.240 --> 1:11:24.520 I've I've never gotten over how much I love dinosaurs 1:11:24.560 --> 1:11:27.720 and other weird organisms that don't exist today. It's it's 1:11:27.760 --> 1:11:30.240 part of my love for monsters, and it's part of 1:11:30.960 --> 1:11:33.960 what keeps bringing me back to paleontology. All right, well, 1:11:33.960 --> 1:11:37.200 we'll leave it at that, but in the meantime, definitely 1:11:37.280 --> 1:11:39.559 check out Stuff to Blow your Mind dot Com. I'll 1:11:39.640 --> 1:11:41.920 check out the landing page for this episode because again 1:11:41.960 --> 1:11:45.800 I'm gonna try to try to include images, illustrations of 1:11:46.040 --> 1:11:48.800 fossil representations, whatever I can find for each of the 1:11:48.920 --> 1:11:52.479 organisms presented here, so you can have some additional visual 1:11:52.560 --> 1:11:55.799 idea of what we're talking about. And I'll include links 1:11:56.160 --> 1:11:58.479 back to some of our other episodes that have dealt 1:11:58.560 --> 1:12:01.160 with prehistoric organisms. And if you want to get in 1:12:01.200 --> 1:12:03.840 touch with us directly with feedback about this episode or 1:12:03.880 --> 1:12:07.000 any other to suggest future episode topic. You can always 1:12:07.080 --> 1:12:09.840 email us at blow the Mind at how stuff works 1:12:09.960 --> 1:12:22.599 dot com for more on this and thousands of other topics. 1:12:22.760 --> 1:12:47.040 Does it how stuff works dot com