WEBVTT - Listener Mail: Fields of Ancient Void 0:00:02.960 --> 0:00:08.280 Welcome to Stuff to Blow Your Mind production of iHeartRadio. Hello, 0:00:08.320 --> 0:00:11.280 and welcome to Stuff to Blow Your Mind the listener mail. 0:00:11.880 --> 0:00:14.760 My name is Joe McCormick. My regular co host Robert 0:00:14.840 --> 0:00:18.160 Lamb is out today, so I'm trekking on my own 0:00:18.239 --> 0:00:22.079 once again, with none but Carney the mailbot at my side. 0:00:22.200 --> 0:00:24.560 But Rob is going to be back with me soon. 0:00:25.360 --> 0:00:28.480 We're going to have a vault episode for you tomorrow. 0:00:28.720 --> 0:00:31.360 That's going to be Tuesday, and then there should be 0:00:31.400 --> 0:00:34.159 an all new short form on Wednesday and a new 0:00:34.240 --> 0:00:37.640 core episode with Rob and me back together on Thursday 0:00:37.720 --> 0:00:41.240 of this week. All right, I guess we should jump 0:00:41.320 --> 0:00:44.920 right into the messages. This first message is from Vic. 0:00:50.120 --> 0:00:53.720 She says, Hi, Robert and Joe. I love your podcast. 0:00:53.800 --> 0:00:56.040 I was hooked after I listened to the multi part 0:00:56.040 --> 0:00:59.040 episode on mirrors, but my favorite of all time is 0:00:59.080 --> 0:01:03.280 the history of the odometer, absolutely blew my mind. For 0:01:03.440 --> 0:01:07.160 my question or possible show suggestion, do you know any 0:01:07.240 --> 0:01:11.400 theories on why humans evolved away from having thick fur 0:01:11.720 --> 0:01:14.880 or hair like that of our closest living relatives in 0:01:14.920 --> 0:01:18.080 the Great Ape family. I heard somewhere recently that humans 0:01:18.120 --> 0:01:21.360 actually have the same amount of hair on average as 0:01:21.400 --> 0:01:25.600 a chimpanzee. But human body hair is so fine and 0:01:25.800 --> 0:01:28.600 or short for the most part that it doesn't appear 0:01:28.640 --> 0:01:30.920 to be fur. I don't know if this is true. 0:01:31.000 --> 0:01:33.840 I had a good laugh wondering if our early ancestors 0:01:33.880 --> 0:01:38.080 started wearing coverings while they still had thick coats, and 0:01:38.200 --> 0:01:42.000 my brain started playing Planet of the Apes. Maybe there 0:01:42.000 --> 0:01:44.840 are advantages to our naked mole rat status in the 0:01:44.840 --> 0:01:48.080 great ape family, maybe something about fleas lice and other 0:01:48.160 --> 0:01:51.200 fur loving pests. Sorry for the long email, would love 0:01:51.240 --> 0:01:52.960 to know what you think. Thank you for all the 0:01:53.000 --> 0:01:56.880 great shows, Vic. Thank you for the message. Vic. Now, 0:01:56.920 --> 0:02:01.000 initially I did not know the answer to your question 0:02:01.200 --> 0:02:06.160 about hair follical density and hair thickness in humans versus chimpanzees. 0:02:06.320 --> 0:02:10.760 But interesting thing in trying to answer your other question, 0:02:11.200 --> 0:02:13.519 I came across an answer to that one too, So 0:02:13.560 --> 0:02:16.520 more on that in a bit. But the main question here, 0:02:16.880 --> 0:02:20.520 how did humans come to be relatively hairless compared to 0:02:20.560 --> 0:02:23.919 our nearest relatives in the animal kingdom. This is a 0:02:23.960 --> 0:02:26.520 really interesting question and one we've looked at on the 0:02:26.520 --> 0:02:29.200 show before, so I just did a little reviewing to 0:02:29.680 --> 0:02:32.600 refresh myself on it. So we don't know for sure. 0:02:32.680 --> 0:02:35.000 With a lot of these evolutionary questions, we can come 0:02:35.080 --> 0:02:37.839 up with good guesses at the answer, but sometimes it's 0:02:37.840 --> 0:02:41.840 hard to know for certain what the actual reasoning or 0:02:41.880 --> 0:02:46.239 pressure driving and adaptation in the distant past was. But 0:02:47.240 --> 0:02:49.919 I think there are some pretty good guesses about what 0:02:50.040 --> 0:02:54.080 drove the human adaptation for comparative nakedness. One thing to 0:02:54.160 --> 0:02:58.120 note starting off is that although we are relatively hairless 0:02:58.200 --> 0:03:01.839 overall compared to most st other mammals, there's a fair 0:03:01.840 --> 0:03:04.600 amount of variation in the amount of body hair present 0:03:04.680 --> 0:03:08.320 on humans, like in between different human individuals, and I 0:03:08.360 --> 0:03:11.160 think it's interesting that there are pretty consistent patterns of 0:03:11.280 --> 0:03:15.520 hairiness versus hairlessness on different regions of the body that 0:03:15.560 --> 0:03:18.720 are common to almost all people. So, for example, we 0:03:18.800 --> 0:03:21.400 don't grow hair on the palms of our hands or 0:03:21.440 --> 0:03:23.839 the soles of our feet for the most part. Though 0:03:23.880 --> 0:03:28.080 if you look, these skin surface patterns are somewhat shared 0:03:28.440 --> 0:03:34.200 by our closest relatives, even the very hairy ones. So chimpanzees, gorillas, 0:03:34.240 --> 0:03:38.360 and other great apes also don't have fur on their palms, 0:03:38.440 --> 0:03:41.360 and this is probably all for the same reason. In 0:03:41.720 --> 0:03:44.440 all of us. It's so that we can have improved 0:03:44.520 --> 0:03:48.240 grip and dexterity. Imagine trying to grip a tree branch, 0:03:48.320 --> 0:03:50.320 to climb a tree, or swing from a tree branch, 0:03:50.800 --> 0:03:54.240 or to manipulate objects in your hands. If those hands 0:03:54.240 --> 0:03:56.760 were covered in fur, things would really kind of slide 0:03:56.760 --> 0:03:59.840 around in there, it seems. However, when it comes to 0:04:00.200 --> 0:04:03.880 the general loss of over the covering the whole body, 0:04:04.120 --> 0:04:08.160 one of the major explanations is that it has to 0:04:08.200 --> 0:04:13.800 do with thermoregulation, the ability to manage the body's internal temperature. 0:04:14.480 --> 0:04:18.120 Fur helps insulate the body against the cold. It's very 0:04:18.200 --> 0:04:21.000 useful for that, and many mammals use it to that end, 0:04:21.480 --> 0:04:25.880 but as an insulation method it's inflexible. A mammal with 0:04:26.040 --> 0:04:30.360 thick fur can't quickly take its fur off when it 0:04:30.400 --> 0:04:33.520 gets hot, so it has to be careful to avoid, say, 0:04:33.600 --> 0:04:38.400 overexerting itself out in the sun. And the thermoregulation hypothesis 0:04:38.440 --> 0:04:42.040 says well, human ancestors, by losing most of their body 0:04:42.080 --> 0:04:47.400 hair massively increased their ability to cool the body, especially 0:04:47.520 --> 0:04:51.640 during exercise in hot climates, maybe under the direct sun. 0:04:52.720 --> 0:04:56.480 And I think one thing that makes the thermoregulation hypothesis 0:04:56.600 --> 0:05:00.599 strong is that the loss of body hair is the 0:05:00.640 --> 0:05:05.400 only observed genetic change that would serve this purpose. In fact, 0:05:05.440 --> 0:05:08.159 you can see other signs that there was intense pressure 0:05:08.160 --> 0:05:12.240 on human ancestors to develop genetic adaptations for cooling the body. 0:05:12.400 --> 0:05:16.760 And a big example here is sweat glands. So if 0:05:16.760 --> 0:05:19.440 I asked you to think what distinguishes us from our 0:05:19.480 --> 0:05:22.640 closest relatives like chimpanzees, what are some body differences you 0:05:22.640 --> 0:05:26.080 can think of? You might think of things like bipedal locomotion. 0:05:26.240 --> 0:05:29.200 We tend to walk upright on two legs, the relative 0:05:29.279 --> 0:05:32.480 lack of body fur as in your question here. Of course, 0:05:33.120 --> 0:05:36.760 other behavioral and intellectual things like the capacity for language 0:05:36.760 --> 0:05:40.600 and so forth. But another major difference is that humans 0:05:40.640 --> 0:05:45.080 have way more sweat glands, also known as ekrone glands. 0:05:45.560 --> 0:05:48.800 We have something like ten times the density of ekron 0:05:48.880 --> 0:05:53.400 glands found in animals like chimpanzees and macaques. So we 0:05:53.480 --> 0:05:55.760 are not only the ape that can walk, the ape 0:05:55.800 --> 0:05:58.960 that can talk, We are by far the sweatiest of 0:05:59.000 --> 0:06:02.320 all apes. And so I was looking for some research 0:06:02.360 --> 0:06:05.839 on the genetic basis of this difference in the sweat glands, 0:06:06.560 --> 0:06:08.599 and I found the following study. It was won by 0:06:08.680 --> 0:06:13.000 Daniel aldea at all called repeated mutation of a developmental 0:06:13.120 --> 0:06:18.640 enhancer contributed to human thermoregulatory evolution. This was published in 0:06:18.839 --> 0:06:23.480 Proceedings the National Academy of Sciences in twenty twenty one, 0:06:23.720 --> 0:06:26.680 and it was by a team of researchers I think 0:06:26.720 --> 0:06:30.440 primarily from the University of Pennsylvania School of Medicine, and 0:06:30.480 --> 0:06:33.719 they write in their summary quote, the effectiveness of human 0:06:33.800 --> 0:06:38.960 thermoregulatory sweating is underlain by the evolution of a dramatically 0:06:39.120 --> 0:06:44.239 increased density of water secreting ekrone sweat glands in human 0:06:44.320 --> 0:06:48.240 skin relative to that of other primates. Here we show 0:06:48.320 --> 0:06:52.520 that the accumulation of human specific mutations in a developmental 0:06:52.640 --> 0:06:57.560 enhancer collectively promoted the production of ekrone glands in humans 0:06:57.880 --> 0:07:02.520 by upregulating the expression of the engrailed one also known 0:07:02.560 --> 0:07:06.159 as the e in one transcription factor in the skin. 0:07:07.000 --> 0:07:10.239 So here is apparently the genetic basis of the difference. 0:07:10.400 --> 0:07:12.480 I was reading some comments by the authors in a 0:07:12.560 --> 0:07:16.200 press release associated with this study, and one thing they 0:07:16.280 --> 0:07:18.720 highlighted is that while a lot of other human genetic 0:07:18.760 --> 0:07:22.840 traits that show differences from our nearest relatives are thought 0:07:22.880 --> 0:07:26.200 to come from a complex interaction of different heritable factors. 0:07:26.560 --> 0:07:31.280 The human beings ability to outsweat its relatives seems largely 0:07:31.320 --> 0:07:36.280 traceable to mutations in one single regulatory region called the 0:07:36.560 --> 0:07:42.040 he CE eighteen. Now also related to the study here, Vic, 0:07:42.120 --> 0:07:43.800 We're going to come back to something you asked in 0:07:43.880 --> 0:07:47.120 your email, the part where you wrote, quote, I heard 0:07:47.160 --> 0:07:51.040 something recently that humans actually have the same amount of 0:07:51.080 --> 0:07:53.760 hair on average as a chimpanzee. But human body hair 0:07:53.840 --> 0:07:55.880 is so fine and or short for the most part 0:07:56.160 --> 0:07:59.000 that it doesn't appear to be fur. Well, I was 0:07:59.040 --> 0:08:01.800 reading about the paper I just mentioned in an exerpt 0:08:01.840 --> 0:08:04.960 from a book called The Joy of Sweat, The Strange 0:08:04.960 --> 0:08:09.280 Science of Perspiration by Sarah Everts. This exerpt was published 0:08:09.280 --> 0:08:12.160 by Science Friday, and Everts here cites one of the 0:08:12.200 --> 0:08:15.080 authors of the twenty twenty one study, who is the 0:08:15.280 --> 0:08:20.960 upin Geneticistiana Kambarov, and she confirms that quote we look naked, 0:08:21.160 --> 0:08:24.280 but we are not actually naked. We have the same 0:08:24.360 --> 0:08:28.480 density of hair follicles as apes have fur follicles end 0:08:28.480 --> 0:08:32.560 of quote. But most of those hairs are miniatureized. They're 0:08:32.559 --> 0:08:35.560 shrunken down to the point that they are nearly invisible. 0:08:36.160 --> 0:08:39.080 So yes, it appears vic what you heard was true. 0:08:39.120 --> 0:08:42.160 It's not that we have fewer hair follicles. It's just 0:08:42.240 --> 0:08:45.440 that most of that hair doesn't really it doesn't really 0:08:45.480 --> 0:08:49.640 become you know, it doesn't achieve hair's full potential, so 0:08:49.679 --> 0:08:53.200 we don't have fur coats. Instead, we got little bumps 0:08:53.240 --> 0:08:57.720 and sweat glands and things. So it looks like human 0:08:57.760 --> 0:09:01.640 ancestors underwent multiple changes would have helped keep our bodies 0:09:01.720 --> 0:09:05.280 cooler than would be possible if those bodies were more 0:09:05.440 --> 0:09:08.800 like the bodies of chimpanzees. And those changes are the 0:09:08.840 --> 0:09:12.000 reduction and body fur and the higher density of sweat 0:09:12.040 --> 0:09:15.800 glands for evaporative cooling. Now, another thing that's worth noting 0:09:15.880 --> 0:09:19.960 is that these adaptations stack. The loss of body hair 0:09:20.120 --> 0:09:24.720 appears to make sweating more useful as a cooling technique, 0:09:24.800 --> 0:09:27.120 because if you think about it, it's like harder to 0:09:27.160 --> 0:09:30.080 achieve much evaporative cooling if you are covered in a 0:09:30.160 --> 0:09:33.960 mat of fur. And it also seems that these two 0:09:34.040 --> 0:09:37.240 changes could even have a common cause. Coming back to 0:09:37.280 --> 0:09:41.880 that exerpt from the book by Sarah Everts, she's writing 0:09:41.880 --> 0:09:46.240 about research by Camperov and colleagues. Quote. Camberov and her 0:09:46.240 --> 0:09:50.280 colleagues are finding evidence that the biological signals nudging these 0:09:50.280 --> 0:09:55.559 precursor cells toward an ekrone sweat gland density also inhibit 0:09:55.720 --> 0:09:59.439 the formation of hair. So given all this evidence, it 0:09:59.480 --> 0:10:02.480 seems very plausible to me that there was a pressure 0:10:02.520 --> 0:10:06.920 on our ancestors causing them to survive and reproduce better 0:10:07.080 --> 0:10:10.840 if they could cool their bodies more efficiently. Now, what 0:10:10.840 --> 0:10:14.319 would that pressure be. It could be that they changed habitats, 0:10:14.520 --> 0:10:17.720 maybe say from living in fully shaded forests with like 0:10:17.720 --> 0:10:22.160 a thick canopy cover to living in more direct sunlight, 0:10:22.240 --> 0:10:25.000 either in an open savannah or in a woodland that 0:10:25.120 --> 0:10:28.280 was less dense with thinner canopy and more direct sun. 0:10:28.840 --> 0:10:31.560 Or it could be a change in survival niches, behavioral 0:10:31.600 --> 0:10:36.720 survival niches, So imagine a change to relying on more strenuous, 0:10:36.760 --> 0:10:41.520 prolonged exercise to survive, maybe through endurance running during hunting 0:10:41.600 --> 0:10:43.880 or something else. Or there could be reasons that we're 0:10:43.920 --> 0:10:47.360 not even thinking of that would have caused this need 0:10:47.440 --> 0:10:52.640 to cool the body. So the thermoregulation explanation seems pretty 0:10:52.640 --> 0:10:55.959 strong to me, maybe the probably the strongest explanation I've 0:10:55.960 --> 0:10:58.600 come across, But there are plenty of other possible reasons 0:10:58.640 --> 0:11:02.760 for ancestral fur laws, and they could have been complementary 0:11:02.800 --> 0:11:05.520 to one another. I'm not going to cover all of 0:11:05.559 --> 0:11:08.880 the hypotheses out there, but one other idea we've talked 0:11:08.920 --> 0:11:12.760 about on the show before is the role of ectoparasites. 0:11:13.040 --> 0:11:16.080 And here I'm going to consult a paper called a 0:11:16.200 --> 0:11:19.679 naked ape would have fewer parasites. This was published in 0:11:19.720 --> 0:11:23.000 two thousand and three by Mark Pagel and Walter Bodner 0:11:23.360 --> 0:11:26.240 in Proceedings of the Royal Society of London Series B 0:11:26.440 --> 0:11:32.080 Biological Sciences. From their abstract, they write, quote, Unusually among 0:11:32.120 --> 0:11:35.640 the mammals, humans lack an outer layer of protective fur 0:11:35.840 --> 0:11:39.960 or hair. We propose the hypothesis that humans evolved hairlessness 0:11:39.960 --> 0:11:46.000 to reduce parasite loads, especially ectoparasites that may carry disease. 0:11:46.480 --> 0:11:50.200 We suggest that hairlessness is maintained by these naturally selected 0:11:50.240 --> 0:11:55.720 benefits and bisexual selection operating on both sexes. Hairlessness is 0:11:55.760 --> 0:11:58.840 made possible in humans owing to their unique abilities to 0:11:58.880 --> 0:12:04.040 regulate their environment via fire, shelter, and clothing. So, to 0:12:04.160 --> 0:12:08.600 summarize elements of this hypothesis, you know we can get ticks, 0:12:08.720 --> 0:12:12.840 we can get lice, and these parasites infest body hair, 0:12:13.040 --> 0:12:15.880 they become harder to remove if that hair is thick, 0:12:16.280 --> 0:12:19.360 and they're not just annoying like they spread disease. So 0:12:19.400 --> 0:12:22.600 they do actually have an impact on survival and fitness 0:12:22.640 --> 0:12:27.400 in a natural setting. Once humans could control fire and 0:12:27.600 --> 0:12:31.680 could surround themselves with external insulation, now that might be 0:12:31.920 --> 0:12:34.240 what you would think of his clothing, like maybe animal 0:12:34.320 --> 0:12:38.560 skins or grass or other auxiliary materials from the environment, 0:12:38.679 --> 0:12:41.160 or it could be thinking of shelters. All of these 0:12:41.240 --> 0:12:46.440 changes make it less important to have biological equipment for 0:12:46.559 --> 0:12:50.000 keeping warm, meaning the fur that other mammals have for 0:12:50.120 --> 0:12:55.000 warmth is just less necessary for survival if you've got fire, clothes, shelter. 0:12:55.480 --> 0:13:00.000 It's also possible that if hairlessness enhances survival benefits by 0:13:00.040 --> 0:13:05.040 reducing parasite loads, it could also help enhance reproductive fitness 0:13:05.080 --> 0:13:09.319 through sexual selection by providing an honest signal to potential 0:13:09.400 --> 0:13:13.240 mates of the lack of external parasites. Sort of, you know, 0:13:13.800 --> 0:13:16.200 look and see how attractive I am, And in this case, 0:13:16.240 --> 0:13:21.840 attractive means relatively free of lice and ticks. And there's 0:13:21.840 --> 0:13:25.600 another interesting point of comparison the authors make. They say, 0:13:25.679 --> 0:13:28.880 you know, what are some other mammals that are relatively hairless, well, 0:13:28.880 --> 0:13:32.480 one would be naked mole rats. These are animals that 0:13:32.520 --> 0:13:36.560 live in large colonies underground where you would expect a 0:13:36.600 --> 0:13:43.079 lot of parasite transmission, but their hairlessness offers resistance against ectoparasites. 0:13:43.559 --> 0:13:45.760 And they can of course cope with the lack of 0:13:45.800 --> 0:13:48.760 fur for warmth because they huddle together and they share 0:13:48.800 --> 0:13:51.440 body heat and they stay away from cold air in 0:13:51.480 --> 0:13:56.480 their subterranean layers. So what a naked mole rat has 0:13:56.520 --> 0:14:00.600 in a warmth from underground rat piles? We have in 0:14:00.720 --> 0:14:05.800 technology through fire and clothing, and I guess in evaluating 0:14:05.800 --> 0:14:09.439 this hypothesis, I would have questions about, Like my big 0:14:09.520 --> 0:14:12.360 questions would be like, how do the timelines compare. What 0:14:12.559 --> 0:14:17.120 is the evidence of when our ancestors started undergoing mutations 0:14:17.160 --> 0:14:20.360 to lose their fur, and how would that match up 0:14:20.400 --> 0:14:23.920 against to our best guests at the timeline when we 0:14:23.960 --> 0:14:28.160 started controlling fire or wearing clothes or had other forms 0:14:28.200 --> 0:14:33.360 of external insulation. But anyway, very interesting question. Thank you, vic. 0:14:41.960 --> 0:14:45.040 All Right, this next message is about our episodes on 0:14:45.200 --> 0:14:49.480 heart burial, heart removal and heart burial. It's from Kenneth 0:14:49.560 --> 0:14:53.520 in Glasgow. Kenneth says Hi, Rob and Joe, thanks for 0:14:53.560 --> 0:14:56.520 the fascinating episodes discussing all the ins and outs of 0:14:56.600 --> 0:15:00.040 heart removal. You finally helped me make sense of the 0:15:00.080 --> 0:15:04.160 post mortem journey of the Heart of the Bruce. Robert 0:15:04.200 --> 0:15:07.680 the Bruce was the Scottish king responsible for the defeat 0:15:07.720 --> 0:15:12.880 of the English army at Bannockburn, effectively ending plantagenet claims 0:15:12.920 --> 0:15:15.960 to the Scottish throne. When it came time for him 0:15:15.960 --> 0:15:18.600 to consider his own death, he requested that his heart 0:15:18.680 --> 0:15:21.640 be taken on a tour of the Holy Land. His 0:15:21.960 --> 0:15:25.680 entrails were buried where he died in Cardross, and his 0:15:25.800 --> 0:15:29.840 body went to dunferm Lean Alley. A night by the 0:15:29.920 --> 0:15:32.680 name of Sir James Douglas took the heart in the 0:15:32.720 --> 0:15:37.680 form of a metal urn on a necklace with him. 0:15:38.000 --> 0:15:40.400 I assume this means on one of the Crusades, but 0:15:40.480 --> 0:15:44.640 I'm not sure. But then Kenneth continues, but on the 0:15:44.680 --> 0:15:47.880 way he was called to help fight the Moors in Spain. 0:15:48.520 --> 0:15:52.360 At some point during the Battle of Taba, Douglas is 0:15:52.360 --> 0:15:54.680 said to have hurled the heart into the midst of 0:15:54.720 --> 0:15:58.640 the enemy with the cry, lead on, braveheart, I'll follow 0:15:58.680 --> 0:16:02.840 the entheses. No prizes for guessing where the movie got 0:16:02.880 --> 0:16:08.080 its title. Douglas, killed in battle, was then transported back 0:16:08.120 --> 0:16:11.880 to Scotland with the heart and buried near Melrose Abbey. 0:16:11.960 --> 0:16:15.440 The heart itself was exhumed and reburied within the abbey 0:16:15.480 --> 0:16:18.800 in nineteen ninety six. I had no idea heart burial 0:16:18.880 --> 0:16:21.440 had been such a widespread tradition, so the story of 0:16:21.520 --> 0:16:24.760 Robert the Bruce's heart had always seemed very strange. Thank 0:16:24.800 --> 0:16:28.920 you for giving it context. Kenneth from Glasgow. Thank you, Kenneth. 0:16:29.160 --> 0:16:32.440 Very interesting all right. This next message is in response 0:16:32.480 --> 0:16:42.360 to our episodes on tea. This is from Eric. Eric says, hey, 0:16:42.440 --> 0:16:45.080 Rob and Joe. I enjoyed your episodes about tea and 0:16:45.240 --> 0:16:48.160 its accessories. One thing that could have been mentioned is 0:16:48.200 --> 0:16:52.120 the Utah teapot, which is an object commonly rendered when 0:16:52.160 --> 0:16:56.240 testing computer graphics. I remember seeing teapots everywhere in my 0:16:56.280 --> 0:16:59.120 early computer science courses, and it's pretty common to see 0:16:59.120 --> 0:17:03.040 a teapot hid or not so hidden in various video 0:17:03.080 --> 0:17:08.359 games or rendering engines like CAD software that's computer aided 0:17:08.400 --> 0:17:11.199 design or something CAD software. You can look up what 0:17:11.200 --> 0:17:13.879 it stands for. It's sort of an in joke for 0:17:14.040 --> 0:17:17.520 computer nerds. I always thought that a teapot was an 0:17:17.520 --> 0:17:20.760 odd choice since everyone knows that software is ultimately fueled 0:17:20.800 --> 0:17:24.439 by coffee. But it makes sense since the teapot is 0:17:24.480 --> 0:17:28.040 a really unique and non uniform object, so it's more 0:17:28.080 --> 0:17:32.080 complicated than a simple sphere or polyhedron. But it's also 0:17:32.240 --> 0:17:35.080 smooth and shiny, which is a lot easier to render 0:17:35.119 --> 0:17:38.359 than something with rough or fuzzy textures. Thanks for the 0:17:38.359 --> 0:17:42.960 great episodes, Eric, Okay. One last message this comes from Kurt. 0:17:48.280 --> 0:17:51.600 Kurt says, hey guys, longtime listener over the years. I 0:17:51.640 --> 0:17:53.600 don't know why this just occurred to me today. I 0:17:53.640 --> 0:17:56.520 was listening to the three part series on tea recently. 0:17:57.119 --> 0:17:59.560 In the third part, Joe started to talk about the 0:17:59.680 --> 0:18:04.520 drip tea spout problem and Russell's teapot analogy. This started 0:18:04.560 --> 0:18:07.359 to take the conversation outside the realm of the subject, 0:18:07.440 --> 0:18:10.360 with just a thread of the original topic. This isn't 0:18:10.359 --> 0:18:12.960 a criticism at all. I like the tangents that bring 0:18:13.080 --> 0:18:15.760 up the things that I probably wouldn't otherwise think about 0:18:15.840 --> 0:18:19.240 in that moment. My question is what is your process 0:18:19.280 --> 0:18:22.000 for creating episodes based on a topic. Do you have 0:18:22.040 --> 0:18:25.359 discussions beforehand about areas you'd like to investigate, or do 0:18:25.400 --> 0:18:29.360 you both investigate certain areas individually and just see where 0:18:29.400 --> 0:18:32.040 it takes you without the other person knowing what topics 0:18:32.040 --> 0:18:34.520 you'll bring up. If so, is it more of a 0:18:34.560 --> 0:18:37.920 surprise where the conversations take you based on this, as 0:18:38.040 --> 0:18:40.760 neither of you would have a full indication as to 0:18:40.760 --> 0:18:43.480 where a conversation might go. I don't know if you've 0:18:43.480 --> 0:18:45.680 outlined this before. You guys have a ton of episodes 0:18:45.680 --> 0:18:49.960 and mail ins, so it might have been addressed previously. Anyway, 0:18:49.960 --> 0:18:52.960 Thanks for what you guys are doing. Love being in 0:18:53.200 --> 0:18:57.720 on the conversations no matter where they go. Kurt, Well, Kurt, 0:18:57.800 --> 0:19:02.240 thank you for the message. Yeah, I guess our method 0:19:02.520 --> 0:19:05.639 is somewhat free form, but I'll try to explain as 0:19:05.640 --> 0:19:08.800 best I can. We don't approach every episode exactly the 0:19:08.840 --> 0:19:11.720 same way, but most of the time it looks something 0:19:11.760 --> 0:19:13.800 like this. You know, one of us gets an idea 0:19:13.960 --> 0:19:17.280 and shares it with the other and we will talk 0:19:17.320 --> 0:19:19.480 it over and figure out if it will actually make 0:19:19.520 --> 0:19:23.400 for a good episode. So after we do that, after 0:19:23.400 --> 0:19:26.400 we figure out that something is probably a solid episode 0:19:26.440 --> 0:19:28.960 or has a series in it, we you know, work 0:19:29.080 --> 0:19:33.560 from a shared notes document which contains some pre written 0:19:33.600 --> 0:19:36.119 thoughts and information that we want to refer back to. 0:19:36.320 --> 0:19:38.480 But it's not like a strict script. So what you 0:19:38.600 --> 0:19:41.840 hear in an episode is a mix of some pre 0:19:41.920 --> 0:19:46.640 written thoughts, some paraphrasing and summarizing of notes, some extemporaneous 0:19:46.680 --> 0:19:50.199 thoughts and conversation. And ultimately this means that we know 0:19:50.359 --> 0:19:53.240 some things, but not everything that's going to happen going 0:19:53.320 --> 0:19:56.320 in and so are there are still often plenty of 0:19:56.359 --> 0:19:59.240 surprises we have for ourselves and for each other during 0:19:59.240 --> 0:20:03.240 a recording session, and sometimes we do agree beforehand on 0:20:03.280 --> 0:20:08.040 which subtopics we'll focus on, but sometimes not often. I've 0:20:08.080 --> 0:20:10.040 said this on the show before, but the you know, 0:20:10.320 --> 0:20:13.280 the contents of the episode are kind of an emergent 0:20:14.000 --> 0:20:17.159 result of the research process. It's not like we can 0:20:17.680 --> 0:20:21.520 know before researching what all of the interesting things to 0:20:21.520 --> 0:20:23.640 talk about will be. It's kind of through the process 0:20:23.640 --> 0:20:28.400 of reading about something that we discover even what questions 0:20:28.440 --> 0:20:31.680 there are to look into. So so, yeah, a lot 0:20:31.720 --> 0:20:33.720 of times we just kind of end up going on 0:20:33.760 --> 0:20:36.520 our own tangents and then we have something interesting to 0:20:36.520 --> 0:20:40.120 come share with each other when we return. But other times, yeah, 0:20:40.119 --> 0:20:42.040 we know about certain things we're going to look into, 0:20:42.080 --> 0:20:45.600 and we we kind of divvy it up accordingly. So 0:20:45.640 --> 0:20:47.960 to answer your question as directly as I can, it's 0:20:48.000 --> 0:20:50.720 just it's a mixed bags. Our conversations on Mike are 0:20:51.240 --> 0:20:54.880 partly predictable to each other and partly surprising to each other. 0:20:55.600 --> 0:20:57.520 All right, I think that's going to do it for 0:20:57.760 --> 0:21:03.199 the mail bag today. One more reminder. We're going to 0:21:03.240 --> 0:21:06.760 be running a vault episode tomorrow, and then we'll be 0:21:06.800 --> 0:21:10.400 back with new episodes for you on Wednesday, and going 0:21:10.440 --> 0:21:12.560 forward after that, we should have a new Core episode 0:21:12.600 --> 0:21:15.680 for you on Thursday of this week. If you're new here, 0:21:16.000 --> 0:21:18.680 this is the Stuff to Blow your Mind podcast. Our 0:21:18.680 --> 0:21:22.520 Core episodes publish every Tuesday and Thursday. Those are most 0:21:22.560 --> 0:21:25.800 often about science, but we also hop across disciplines and 0:21:26.000 --> 0:21:28.880 get into all sorts of things. On Mondays, we read 0:21:28.920 --> 0:21:32.040 back listener mail in episodes like this one, though usually 0:21:32.280 --> 0:21:37.000 both Robert and I are co hosting them. On Wednesdays, 0:21:37.200 --> 0:21:41.000 we do a short form episode called The Artifact or 0:21:41.040 --> 0:21:44.120 the Monster Fact. On Fridays. When the week is done, 0:21:44.640 --> 0:21:47.000 it's time for Weird House Cinema. That's a series we 0:21:47.040 --> 0:21:49.680 do where Rob and I just to feature and discuss 0:21:49.720 --> 0:21:54.120 a weird movie. Weird is really the only criterion. Sometimes 0:21:54.119 --> 0:21:57.000 we look at great movies, sometimes we look at bad movies. 0:21:57.200 --> 0:22:01.360 Some are well known classics, are obscure that nobody's ever 0:22:01.400 --> 0:22:04.080 heard about. Basically all of its fair game as long 0:22:04.119 --> 0:22:07.480 as it's weird. And then, finally, on Saturday's we feature 0:22:07.640 --> 0:22:11.880 an episode from The Fault So Big thanks to our 0:22:11.960 --> 0:22:15.200 audio producer JJ Pauseway. If you would like to get 0:22:15.240 --> 0:22:17.840 in touch with us with feedback on this episode or 0:22:17.840 --> 0:22:21.240 any other, to share your thoughts, or to share something 0:22:21.840 --> 0:22:25.080 that you think we'd be interested in, to suggest a 0:22:25.160 --> 0:22:27.560 topic for the future, or just to say hello, you 0:22:27.560 --> 0:22:30.600 can email us at contact at stuff to blow your 0:22:30.600 --> 0:22:39.720 Mind dot com. Stuff to Blow Your Mind is a 0:22:39.720 --> 0:22:42.920 production of iHeartRadio. For more podcasts from my heart Radio, 0:22:43.160 --> 0:22:46.240 visit the iHeartRadio app, Apple Podcasts, or wherever you listen 0:22:46.320 --> 0:22:47.240 to your favorite shows.