1 00:00:03,080 --> 00:00:07,160 Speaker 1: Welcome to Stuff to Blow Your Mind production of iHeartRadio. 2 00:00:12,880 --> 00:00:15,120 Speaker 2: Hey, welcome to Stuff to Blow Your Mind. My name 3 00:00:15,160 --> 00:00:16,200 Speaker 2: is Robert Lamb. 4 00:00:16,200 --> 00:00:18,560 Speaker 3: And I am Joe McCormick, and we're back with Part 5 00:00:18,600 --> 00:00:22,720 Speaker 3: two in our series on parrotfish, a group of related 6 00:00:22,800 --> 00:00:27,440 Speaker 3: fishes containing about ninety to one hundred species worldwide, notable 7 00:00:27,560 --> 00:00:31,400 Speaker 3: for their powerful beak like mouths made out of rows 8 00:00:31,400 --> 00:00:36,160 Speaker 3: of fused teeth. In the previous episode, we talked about 9 00:00:36,200 --> 00:00:40,280 Speaker 3: some basics about the biology and taxonomy of parrotfish species. 10 00:00:40,760 --> 00:00:44,600 Speaker 3: We talked about their diet and feeding behavior. Parrotfish are 11 00:00:44,680 --> 00:00:49,519 Speaker 3: usually considered herbivores or something equivalent to herbivores. They survived 12 00:00:49,600 --> 00:00:54,120 Speaker 3: by grazing for algae, microorganisms, to trite us, and sometimes 13 00:00:54,200 --> 00:00:58,520 Speaker 3: invertebrate animals like coral polyps, along the surfaces of rocks 14 00:00:58,560 --> 00:01:03,520 Speaker 3: and coral skeletons within coral reef environments. We talked about 15 00:01:03,560 --> 00:01:07,399 Speaker 3: the fact that some parrotfish species end up biting or 16 00:01:07,600 --> 00:01:11,959 Speaker 3: scraping off significant chunks of hard matter from the rocks 17 00:01:12,000 --> 00:01:15,240 Speaker 3: and coral that they scour for food, and then grinding 18 00:01:15,319 --> 00:01:20,040 Speaker 3: up these coral skeletons and minerals in their phyryngial mills. 19 00:01:20,240 --> 00:01:23,280 Speaker 3: It's kind of like horror movie machinery in the back 20 00:01:23,319 --> 00:01:25,120 Speaker 3: of their throats. I think we compared it to like 21 00:01:25,160 --> 00:01:29,760 Speaker 3: a bone transmission gear and then defecating what's left in 22 00:01:29,800 --> 00:01:32,840 Speaker 3: the form of sand. And so as a result, parrotfish 23 00:01:32,840 --> 00:01:36,000 Speaker 3: are major figures in the erosion of coral reefs and 24 00:01:36,080 --> 00:01:38,840 Speaker 3: in the production of sand. So if you walk across 25 00:01:38,880 --> 00:01:41,720 Speaker 3: a white sandy beach in the tropics where there are 26 00:01:41,800 --> 00:01:44,880 Speaker 3: coral reefs nearby, there is a good chance that most 27 00:01:44,959 --> 00:01:47,840 Speaker 3: of the sand under your feet was at one point 28 00:01:47,920 --> 00:01:51,600 Speaker 3: parrotfish poop. This is true of reef islands built entirely 29 00:01:51,640 --> 00:01:54,760 Speaker 3: out of reef sediment, like the Maldives, but also true 30 00:01:54,800 --> 00:01:57,640 Speaker 3: of some white sandy beaches in places like Hawaii and 31 00:01:57,680 --> 00:02:01,320 Speaker 3: the Caribbean. We talked also about writings on parrotfish from 32 00:02:01,320 --> 00:02:05,680 Speaker 3: the ancient world, how the Romans prized certain parrotfishes as 33 00:02:05,800 --> 00:02:08,720 Speaker 3: food items, and why they thought they were in first 34 00:02:08,760 --> 00:02:12,760 Speaker 3: place among the culinary uses of fish. How they developed 35 00:02:12,800 --> 00:02:15,400 Speaker 3: a range of beliefs about these fish, some of which 36 00:02:15,440 --> 00:02:19,280 Speaker 3: were fairly biologically accurate, such as the belief that these 37 00:02:19,320 --> 00:02:23,320 Speaker 3: fish are herbivorous grazers they sort of are, and that 38 00:02:23,360 --> 00:02:26,720 Speaker 3: they produce audible sounds underwater as they scrape the rocks 39 00:02:26,760 --> 00:02:29,960 Speaker 3: and coral for food. Also true, other beliefs not quite 40 00:02:30,040 --> 00:02:32,760 Speaker 3: so accurate. For example, Rob, didn't you talk about this 41 00:02:32,840 --> 00:02:37,480 Speaker 3: idea that they cooperate altruistically to save one another from traps? 42 00:02:37,600 --> 00:02:41,840 Speaker 2: Yes, and in this became an enduring and long lasting 43 00:02:41,880 --> 00:02:45,359 Speaker 2: symbol of friendship, which doesn't really hold up to how 44 00:02:45,360 --> 00:02:46,320 Speaker 2: they actually behave. 45 00:02:46,760 --> 00:02:49,600 Speaker 3: But we also talked last time about some interesting beliefs 46 00:02:49,639 --> 00:02:53,679 Speaker 3: about parrotfishes in Hawaiian mythology, where the parrotfish is sort 47 00:02:53,720 --> 00:02:57,000 Speaker 3: of a progenitor of other sea life and enters into 48 00:02:57,080 --> 00:03:01,119 Speaker 3: a pact with a Hawaiian mythical hero who can sort 49 00:03:01,120 --> 00:03:04,920 Speaker 3: of call upon his friendship with the parrotfish in order 50 00:03:04,960 --> 00:03:08,160 Speaker 3: to produce an abundance of fish catch for the people. 51 00:03:08,880 --> 00:03:12,000 Speaker 3: And then finally, we also talked about research on parrotfish teeth, 52 00:03:12,040 --> 00:03:14,960 Speaker 3: which are made out of some of the hardest, stiffest, 53 00:03:14,960 --> 00:03:18,600 Speaker 3: and most resilient biominerals known, even to the extent that 54 00:03:18,639 --> 00:03:21,920 Speaker 3: they are being investigated as a model for high durability 55 00:03:22,200 --> 00:03:26,040 Speaker 3: synthetic materials in the lab. So that was part one, 56 00:03:26,080 --> 00:03:28,840 Speaker 3: and today we're back to talk some more about parrotfish. 57 00:03:29,040 --> 00:03:31,639 Speaker 2: Yeah, And I just want to drive home that if 58 00:03:31,639 --> 00:03:35,160 Speaker 2: you haven't had the opportunity to observe parrotfish in the wild, 59 00:03:35,720 --> 00:03:38,920 Speaker 2: and you find yourself traveling to or in an area 60 00:03:39,320 --> 00:03:43,480 Speaker 2: where there are reef environments and there is some manner 61 00:03:43,520 --> 00:03:47,360 Speaker 2: of snorkeling going on, go check it out. Oftentimes, you know, 62 00:03:47,360 --> 00:03:53,520 Speaker 2: there are various snorkeling companies and small businesses that are 63 00:03:53,600 --> 00:03:55,720 Speaker 2: very approachable. You don't have to have a lot of 64 00:03:55,720 --> 00:03:58,800 Speaker 2: experience to try these out. Again. These are often we're 65 00:03:58,840 --> 00:04:03,200 Speaker 2: talking like shallow water environments, and in these environments there's 66 00:04:03,240 --> 00:04:08,200 Speaker 2: almost always some sort of parrotfish to observe. And if 67 00:04:08,280 --> 00:04:11,680 Speaker 2: that's not your cup of tea, I want to add 68 00:04:11,680 --> 00:04:13,880 Speaker 2: that for anyone who would like to see various parrotfish 69 00:04:13,880 --> 00:04:16,640 Speaker 2: in action as well as other fish, I highly recommend 70 00:04:16,680 --> 00:04:21,200 Speaker 2: checking out Coral City Camera. That's just Coralcitycamera dot com 71 00:04:21,320 --> 00:04:23,560 Speaker 2: or you can look it up and search. It's an 72 00:04:23,600 --> 00:04:28,599 Speaker 2: underwater camera streaming live from an urban coral reef in Miami, Florida. 73 00:04:29,120 --> 00:04:31,960 Speaker 2: It's pretty cool and if you watch long enough, you 74 00:04:32,000 --> 00:04:33,920 Speaker 2: will see some parrotfish. 75 00:04:33,360 --> 00:04:36,320 Speaker 3: In action pursuing their new career as streamers. 76 00:04:36,839 --> 00:04:40,480 Speaker 2: Yes, yes, so We're going to get into parrotfish reproduction 77 00:04:41,000 --> 00:04:43,560 Speaker 2: here in a bit, But first up, we have this 78 00:04:44,200 --> 00:04:46,960 Speaker 2: other delightful area to look at something that I wasn't 79 00:04:46,960 --> 00:04:49,840 Speaker 2: familiar with at all concerning parrotfish. Joe, do you want 80 00:04:49,839 --> 00:04:51,200 Speaker 2: to get into their mucus? 81 00:04:51,400 --> 00:04:51,599 Speaker 3: Oh? 82 00:04:51,680 --> 00:04:52,080 Speaker 2: Do? I? 83 00:04:52,080 --> 00:04:54,280 Speaker 3: I feel like I'm already into their mucus. I've been 84 00:04:54,320 --> 00:04:58,200 Speaker 3: in it all day. So I mentioned in the previous 85 00:04:58,240 --> 00:05:02,240 Speaker 3: episode that the topic parrotfish was one that I initially 86 00:05:02,240 --> 00:05:04,640 Speaker 3: got interested in just by looking at pictures, you know. 87 00:05:04,760 --> 00:05:07,960 Speaker 3: I was looking at like a photo of a parrotfish mouth, 88 00:05:08,240 --> 00:05:10,760 Speaker 3: and I started thinking, what is going on with this 89 00:05:10,839 --> 00:05:14,640 Speaker 3: awesome palisade of fused together teeth? And so there is 90 00:05:14,680 --> 00:05:17,839 Speaker 3: another parrotfish subtopic that I think one could come to 91 00:05:17,920 --> 00:05:22,800 Speaker 3: in exactly the same manner, and that is their mucous cocoons. 92 00:05:23,480 --> 00:05:27,839 Speaker 3: If you look for photos of parrotfish sleeping, you will 93 00:05:27,880 --> 00:05:32,000 Speaker 3: find images of these animals nestled down into cozy little 94 00:05:32,120 --> 00:05:35,400 Speaker 3: niches in the seafloor or within the reef structure, sometimes 95 00:05:35,440 --> 00:05:38,600 Speaker 3: kind of in a recess or a little heidi hole 96 00:05:38,640 --> 00:05:42,400 Speaker 3: in the reef, surrounded by what looks like some kind 97 00:05:42,560 --> 00:05:47,560 Speaker 3: of film. Sometimes it looks like the parrotfish is enclosed 98 00:05:47,640 --> 00:05:52,479 Speaker 3: within a gauzy, transparent orb covered like sometimes covered in glitter. 99 00:05:53,400 --> 00:05:55,839 Speaker 3: If you see these in motion and rob below the 100 00:05:55,880 --> 00:05:58,240 Speaker 3: photos here, I did attach a link to a video 101 00:05:58,320 --> 00:05:59,760 Speaker 3: in the outline that you can look at so you 102 00:05:59,800 --> 00:06:02,919 Speaker 3: can see it moving. If you see these in motion, 103 00:06:03,040 --> 00:06:06,080 Speaker 3: they will appear to undulate in the water, so they're 104 00:06:06,160 --> 00:06:10,840 Speaker 3: kind of jelly like in movement and substance. In other cases, 105 00:06:11,400 --> 00:06:15,200 Speaker 3: this film looks like the fish is wrapped up inside 106 00:06:15,240 --> 00:06:18,880 Speaker 3: a huge funnel spider web that's just covered in sand. 107 00:06:19,600 --> 00:06:22,400 Speaker 3: Which funny thing about that the sand may of course 108 00:06:22,480 --> 00:06:25,240 Speaker 3: be the parrotfish's own excretion from earlier. 109 00:06:26,600 --> 00:06:30,479 Speaker 2: Yeah, I'm looking at the video footage right now. It's 110 00:06:30,520 --> 00:06:32,120 Speaker 2: slimy but beautiful. 111 00:06:32,800 --> 00:06:37,480 Speaker 3: So what is this gossamer bubble around a slumbering fish? 112 00:06:38,200 --> 00:06:42,039 Speaker 3: This is what's known as the parrotfish's mucous cocoon, or 113 00:06:42,080 --> 00:06:47,400 Speaker 3: sometimes in the scientific literature it's mucous envelope, described by 114 00:06:47,440 --> 00:06:50,599 Speaker 3: an author named H. E. Wynn in a scientific article 115 00:06:50,880 --> 00:06:55,640 Speaker 3: in nineteen fifty five as a quote thin, transparent and 116 00:06:55,720 --> 00:07:00,960 Speaker 3: gelatinous mucoid substance which starts as a full the mouth 117 00:07:01,320 --> 00:07:06,840 Speaker 3: and progresses backwards in folds to surround the body. So 118 00:07:07,200 --> 00:07:11,480 Speaker 3: parrotfish are daytime animals. They sleep during the night, they 119 00:07:11,520 --> 00:07:15,080 Speaker 3: wake and feed during the day, and some species have 120 00:07:15,120 --> 00:07:20,600 Speaker 3: been observed to spend roughly an hour before sleep generating 121 00:07:20,960 --> 00:07:24,520 Speaker 3: this jelly like sleeping bag out of mucus from their 122 00:07:24,560 --> 00:07:27,240 Speaker 3: mouths before actually getting to sleep, so it's like a 123 00:07:27,240 --> 00:07:31,840 Speaker 3: bedtime routine. As night is falling, they start spitting out 124 00:07:31,840 --> 00:07:35,000 Speaker 3: the mucus and it starts to envelop their body from 125 00:07:35,000 --> 00:07:39,240 Speaker 3: front to back. So the fish are making themselves bedtime 126 00:07:39,360 --> 00:07:43,720 Speaker 3: slime sacks. But why now? First, as a side note, 127 00:07:44,120 --> 00:07:46,760 Speaker 3: I just wanted to say it is normal for all 128 00:07:46,840 --> 00:07:50,520 Speaker 3: kinds of fish species, not just parrotfish or the other 129 00:07:50,600 --> 00:07:55,760 Speaker 3: related fish. Like some rasses that make these slime sacks. 130 00:07:55,920 --> 00:07:58,160 Speaker 3: It is normal for all kinds of fish to be 131 00:07:58,200 --> 00:08:00,800 Speaker 3: covered in a thin layer of mucus on the outside 132 00:08:00,800 --> 00:08:05,000 Speaker 3: of their skin. This omnipresent slime barrier can provide a 133 00:08:05,080 --> 00:08:08,280 Speaker 3: number of benefits, one of which is osmo regulation, and 134 00:08:08,320 --> 00:08:13,600 Speaker 3: that's maintaining the balance of internal water and solutes such 135 00:08:13,600 --> 00:08:17,800 Speaker 3: as electrolytes. So for example, and osmo regulation function within 136 00:08:17,880 --> 00:08:21,120 Speaker 3: our bodies. Human bodies is maintaining the right level of 137 00:08:21,280 --> 00:08:25,000 Speaker 3: salt in our body fluids. Mucous coverings on all kinds 138 00:08:25,040 --> 00:08:30,240 Speaker 3: of fish help with OSMO regulation. But these mucous coverings 139 00:08:30,240 --> 00:08:32,880 Speaker 3: on the skin also cut down on friction. So the 140 00:08:33,000 --> 00:08:36,560 Speaker 3: slippery layer of mucus on the fish's skin makes it 141 00:08:36,600 --> 00:08:39,839 Speaker 3: easier for the fish to swim along. It's like a 142 00:08:39,920 --> 00:08:44,240 Speaker 3: lubricant for the interface with the surrounding water. It's also 143 00:08:44,400 --> 00:08:47,760 Speaker 3: just physical protection of the skin from contact trauma such 144 00:08:47,760 --> 00:08:51,880 Speaker 3: as cuts and scrapes. It in some cases provides UV 145 00:08:52,040 --> 00:08:56,040 Speaker 3: radiation protection, in some cases might protect the fish from 146 00:08:56,120 --> 00:08:59,720 Speaker 3: noxious chemicals or pollutants in the water, and provides the 147 00:08:59,720 --> 00:09:01,680 Speaker 3: fish protection against drying out. 148 00:09:02,760 --> 00:09:05,000 Speaker 2: So this is of course one of the potential issues. 149 00:09:05,040 --> 00:09:07,280 Speaker 2: And just handling fish such as then like catch and 150 00:09:07,320 --> 00:09:10,320 Speaker 2: release and so forth. The slime isn't just something that's 151 00:09:10,320 --> 00:09:12,320 Speaker 2: on the fish. It's an active barrier. 152 00:09:12,920 --> 00:09:16,360 Speaker 3: Yeah, But that's all just the normal mucus coating common 153 00:09:16,400 --> 00:09:18,959 Speaker 3: to many many fish. What we're talking about here is 154 00:09:18,960 --> 00:09:24,320 Speaker 3: specifically this baggy mucus hyper sleep pod that forms around 155 00:09:24,360 --> 00:09:27,720 Speaker 3: some parrotfish and rasses through the night. So I started 156 00:09:27,760 --> 00:09:30,280 Speaker 3: looking at scientific papers about this to see what I 157 00:09:30,280 --> 00:09:33,520 Speaker 3: could find out. So first I was looking at a 158 00:09:33,640 --> 00:09:37,480 Speaker 3: marine zoology paper from the year nineteen seventy that investigated 159 00:09:37,520 --> 00:09:40,760 Speaker 3: a few species of parrotfish to see how and under 160 00:09:40,800 --> 00:09:44,719 Speaker 3: what conditions the fish would make these cocoons. So this 161 00:09:44,800 --> 00:09:47,920 Speaker 3: is by John E. Byrne, who was a professor of 162 00:09:48,000 --> 00:09:51,360 Speaker 3: zoology at the University of Hawaii. The paper is called 163 00:09:51,480 --> 00:09:56,400 Speaker 3: Mucus envelope formation in two species of Hawaiian parrotfishes, and 164 00:09:56,440 --> 00:09:59,720 Speaker 3: the paper begins by citing previous research by Win and 165 00:09:59,760 --> 00:10:03,560 Speaker 3: co authors on parrotfish from the coral reefs of Bermuda, 166 00:10:04,160 --> 00:10:08,079 Speaker 3: which were observed to make mucus envelopes at night. So 167 00:10:08,280 --> 00:10:11,520 Speaker 3: when and a co author named Bardak argued that the 168 00:10:11,559 --> 00:10:16,040 Speaker 3: purpose of the mucus cocoon of the slimesack was to 169 00:10:16,160 --> 00:10:21,520 Speaker 3: protect the parrotfish from predators while it was sleeping. And 170 00:10:21,559 --> 00:10:25,000 Speaker 3: this is a hypothesis that I've seen repeated in a 171 00:10:25,080 --> 00:10:29,840 Speaker 3: number of sources that maybe somehow the mucus covering will 172 00:10:29,840 --> 00:10:33,199 Speaker 3: help alert the fish more quickly if a predator gets 173 00:10:33,240 --> 00:10:36,080 Speaker 3: close to it, or may in some way help mask 174 00:10:36,280 --> 00:10:40,080 Speaker 3: the fish, maybe mask the fish is sent from predators, 175 00:10:40,520 --> 00:10:43,160 Speaker 3: or provide some kind of benefit along those lines. 176 00:10:43,640 --> 00:10:46,960 Speaker 2: Okay, So, either to some degree a cloaking system, a 177 00:10:47,000 --> 00:10:49,720 Speaker 2: cloaking device, if you will, or perhaps some sort of 178 00:10:49,760 --> 00:10:52,600 Speaker 2: like added security trip wire made out of mucus. 179 00:10:53,200 --> 00:10:55,360 Speaker 3: There you go. Now, we'll get to another explanation in 180 00:10:55,480 --> 00:10:57,120 Speaker 3: just a bit here, but we're not there quite yet. 181 00:10:57,160 --> 00:10:59,800 Speaker 3: First we're gonna look at like and how and when 182 00:10:59,840 --> 00:11:02,959 Speaker 3: the things form. So the author of the study, John Burn, 183 00:11:03,440 --> 00:11:07,680 Speaker 3: begins by investigating envelope formation in a couple of different 184 00:11:07,720 --> 00:11:11,800 Speaker 3: species of parrotfish. There's scas dubious, commonly known as the 185 00:11:11,840 --> 00:11:17,720 Speaker 3: regal parrotfish, and scas per pair. Oh wow, here's a word, 186 00:11:17,840 --> 00:11:22,000 Speaker 3: pers bisilattis there you go, which is commonly called the 187 00:11:22,080 --> 00:11:25,880 Speaker 3: spectacled parrotfish. Both are found in the reefs around Hawaii, 188 00:11:25,920 --> 00:11:28,960 Speaker 3: and I think the spectacled parrotfish may be one of 189 00:11:29,000 --> 00:11:32,280 Speaker 3: the keyfish referred to as oohu and some of the 190 00:11:32,320 --> 00:11:35,440 Speaker 3: Hawaiian legends that we talked about in the last episode. 191 00:11:35,760 --> 00:11:37,920 Speaker 2: Yeah yeah, So Burn. 192 00:11:37,920 --> 00:11:40,960 Speaker 3: Did some experiments on these two species in his laboratory, 193 00:11:41,400 --> 00:11:45,880 Speaker 3: varying conditions of light and darkness within their aquaria, making 194 00:11:46,000 --> 00:11:50,280 Speaker 3: observations of behavior, and then examining the mucus producing organs. 195 00:11:50,640 --> 00:11:55,839 Speaker 3: So previous field observations had found that as daylight intensities decrease. 196 00:11:55,880 --> 00:12:00,520 Speaker 3: As daylight goes down, fewer parrotfishes can be founding around 197 00:12:00,559 --> 00:12:04,520 Speaker 3: the reefs. For the night time, these fish will disperse 198 00:12:04,559 --> 00:12:07,680 Speaker 3: their schools and go into recesses within the reef to 199 00:12:07,840 --> 00:12:11,199 Speaker 3: hide and sleep, and that's where they generate these cocoons. 200 00:12:12,320 --> 00:12:15,679 Speaker 3: Within the lab environment, Burne found that if you shine 201 00:12:15,679 --> 00:12:19,200 Speaker 3: a constant light on these fish for twenty four hours straight, 202 00:12:19,640 --> 00:12:22,280 Speaker 3: they will actually never make a mucus cocoon. You just 203 00:12:22,400 --> 00:12:24,480 Speaker 3: keep shining the light on them, at least for twenty 204 00:12:24,480 --> 00:12:27,480 Speaker 3: four hours't He didn't push the experiment to go that 205 00:12:27,600 --> 00:12:30,680 Speaker 3: much longer because you know, it might just end up 206 00:12:30,679 --> 00:12:33,520 Speaker 3: harming them overall. But for twenty four hours straight you 207 00:12:33,559 --> 00:12:36,439 Speaker 3: shine a light on them and it, you know, nothing happens. 208 00:12:36,720 --> 00:12:38,160 Speaker 2: Yeah, corp, of course, I mean there are a lot 209 00:12:38,200 --> 00:12:41,000 Speaker 2: of things I'm not going to do of some sort 210 00:12:41,000 --> 00:12:45,319 Speaker 2: of an intelligent being from a highly advanced species shines 211 00:12:45,440 --> 00:12:47,760 Speaker 2: artificial light on me for twenty four hours. 212 00:12:47,600 --> 00:12:49,920 Speaker 3: That's right. So the constant light means he never make 213 00:12:49,960 --> 00:12:53,120 Speaker 3: a pod. However, when darkness was introduced, you turned the 214 00:12:53,200 --> 00:12:57,120 Speaker 3: lights off. This triggered twenty two of the thirty parrot 215 00:12:57,120 --> 00:13:00,760 Speaker 3: fish tested to build mucus envelopes, and it was the 216 00:13:00,800 --> 00:13:04,960 Speaker 3: same frequency in the two different species. The fish took 217 00:13:05,080 --> 00:13:08,439 Speaker 3: different amounts of time to finish building their envelopes after 218 00:13:08,480 --> 00:13:11,560 Speaker 3: the light was turned off. The minimum was like thirty minutes, 219 00:13:11,640 --> 00:13:14,920 Speaker 3: maximum was two hundred and forty minutes. Average building time 220 00:13:15,120 --> 00:13:19,439 Speaker 3: was about seventy minutes. However, if you kept the fish 221 00:13:19,559 --> 00:13:22,200 Speaker 3: the parrotfish in the dark after it made its cocoon, 222 00:13:22,920 --> 00:13:25,320 Speaker 3: it did not stay in the cocoon forever. Eventually it 223 00:13:25,320 --> 00:13:29,320 Speaker 3: would emerge on its own. So what did they do 224 00:13:29,400 --> 00:13:32,679 Speaker 3: when they made these things? They would typically rest their 225 00:13:32,720 --> 00:13:36,600 Speaker 3: bodies on the floor of the tank and the seafloor 226 00:13:36,640 --> 00:13:39,560 Speaker 3: in the wild, in an upright position, almost always with 227 00:13:39,679 --> 00:13:43,120 Speaker 3: one side of the body resting against a vertical surface 228 00:13:43,240 --> 00:13:45,520 Speaker 3: like a rock or a coral wall, or, in the 229 00:13:45,520 --> 00:13:48,840 Speaker 3: case of the lab experiments, the aquarium wall. And then 230 00:13:48,880 --> 00:13:52,800 Speaker 3: the cocoon begins. It begins formation at the front of 231 00:13:52,840 --> 00:13:57,640 Speaker 3: the fish around its mouth, and folds of mucus slowly 232 00:13:57,760 --> 00:14:01,720 Speaker 3: move back along the length of the body toward the tail. 233 00:14:01,760 --> 00:14:06,439 Speaker 3: Though interestingly, the mucus never completely closes over the body. 234 00:14:06,800 --> 00:14:09,360 Speaker 3: There is always at least a one to two centimeter 235 00:14:09,559 --> 00:14:12,400 Speaker 3: gap at the back end of the bubble, and Burn 236 00:14:12,520 --> 00:14:17,320 Speaker 3: believes this hole is to evacuate respiratory water that's forced 237 00:14:17,320 --> 00:14:21,920 Speaker 3: out of the buckle cavity, so sort of a breathing hole. Now, 238 00:14:22,040 --> 00:14:24,000 Speaker 3: I mentioned that in a lot of these photos, the 239 00:14:24,040 --> 00:14:27,400 Speaker 3: mucus cocoon seems to sparkle as if it is covered 240 00:14:27,400 --> 00:14:31,640 Speaker 3: in glitter. Burn writes that quote fine debris adhered to 241 00:14:31,680 --> 00:14:36,720 Speaker 3: the envelope's exterior and the outline was thus more clearly defined. However, 242 00:14:36,760 --> 00:14:39,560 Speaker 3: he says this coating of sediment and debris makes the 243 00:14:39,600 --> 00:14:42,840 Speaker 3: bubble appear thin and delicate. This is how A Wind 244 00:14:42,960 --> 00:14:47,520 Speaker 3: described it in that article from the fifties. But Burn 245 00:14:47,680 --> 00:14:52,280 Speaker 3: did an experiment by injecting pigmented particles into the cocoon 246 00:14:52,920 --> 00:14:56,160 Speaker 3: and revealed that actually appearances can be deceiving here because 247 00:14:56,200 --> 00:14:59,440 Speaker 3: the cocoon often does look very thin, it's like a 248 00:14:59,440 --> 00:15:04,440 Speaker 3: wispy spider web or this very very thin kind of 249 00:15:04,440 --> 00:15:07,320 Speaker 3: gossamer like material. But in fact he found when he 250 00:15:07,520 --> 00:15:11,320 Speaker 3: injected the pigmented particles in there, the mucus structure was 251 00:15:11,480 --> 00:15:14,600 Speaker 3: up to six centimeters thick in some places, so it's 252 00:15:14,680 --> 00:15:16,120 Speaker 3: not as wispy as it looks. 253 00:15:16,520 --> 00:15:18,400 Speaker 2: Okay, this would just be the case of there being 254 00:15:18,480 --> 00:15:23,280 Speaker 2: like a thin layer of particles on top of this 255 00:15:23,760 --> 00:15:28,280 Speaker 2: otherwise translucent or semi translucent mucous shielding. They would give 256 00:15:28,280 --> 00:15:30,640 Speaker 2: it the appearance of being super thin when in fact 257 00:15:30,680 --> 00:15:32,200 Speaker 2: it is probably thicker. 258 00:15:32,480 --> 00:15:36,240 Speaker 3: That's right. So dissection of the fish revealed that the 259 00:15:37,000 --> 00:15:41,840 Speaker 3: presence of gland tissue in the buckle cavity correlated with 260 00:15:41,960 --> 00:15:44,520 Speaker 3: whether or not the fish would make a cocoon. It 261 00:15:44,600 --> 00:15:47,880 Speaker 3: was found that fish that did not have this gland 262 00:15:48,000 --> 00:15:51,400 Speaker 3: tissue in the mouth cavity, they did not form the 263 00:15:51,440 --> 00:15:56,240 Speaker 3: mucus cocoons. So that's how they're made and win. But 264 00:15:56,280 --> 00:15:59,520 Speaker 3: what are they for? Well, again, the burn paper mentions 265 00:15:59,560 --> 00:16:03,480 Speaker 3: this hypothesis that the mucus sleeping bag somehow protects the 266 00:16:03,560 --> 00:16:08,080 Speaker 3: fish from large predators. A commonly mentioned predator in the 267 00:16:08,120 --> 00:16:10,560 Speaker 3: reef environment would be the more eel, you know, and 268 00:16:10,560 --> 00:16:12,960 Speaker 3: it can get down there in the recesses and attack. 269 00:16:13,560 --> 00:16:17,280 Speaker 3: But apparently there's some doubt about this because, for example, 270 00:16:17,280 --> 00:16:20,480 Speaker 3: when faced with reef dwelling predators such as more eels, 271 00:16:20,880 --> 00:16:24,600 Speaker 3: there is some evidence that sleeping fish within within a 272 00:16:24,680 --> 00:16:29,240 Speaker 3: cocoon are still vulnerable, like they still get eaten. But 273 00:16:29,360 --> 00:16:32,400 Speaker 3: actually I came across an interesting twenty eleven paper that 274 00:16:32,520 --> 00:16:36,000 Speaker 3: looked directly into the function of the mucus cocoon and 275 00:16:36,360 --> 00:16:39,600 Speaker 3: came to a different conclusion. So this was published in 276 00:16:39,640 --> 00:16:43,480 Speaker 3: the journal Biology Letters by Grutterer at All and the 277 00:16:43,600 --> 00:16:46,600 Speaker 3: title is this will give some of the findings away fish, 278 00:16:46,800 --> 00:16:51,800 Speaker 3: mucus cocoons the mosquito nets of the sea. This was 279 00:16:51,800 --> 00:16:55,120 Speaker 3: in the year twenty eleven. So in this paper the 280 00:16:55,160 --> 00:16:59,080 Speaker 3: authors look at another hypothesis, which is the idea that 281 00:16:59,360 --> 00:17:04,680 Speaker 3: mucus envelopes actually protect the fish inside from parasites such 282 00:17:04,720 --> 00:17:11,160 Speaker 3: as ectoparasitic nathid isopods. These are these little bloodsucking parasites 283 00:17:11,200 --> 00:17:15,560 Speaker 3: that live throughout the ocean, often compared to terrestrial mosquitoes 284 00:17:15,640 --> 00:17:19,399 Speaker 3: and ticks. Raw I attached to a little photo of 285 00:17:19,440 --> 00:17:21,159 Speaker 3: these things for you to look at. They're kind of 286 00:17:21,200 --> 00:17:24,200 Speaker 3: shrimp like in appearance. Maybe look like a cross between 287 00:17:24,240 --> 00:17:27,840 Speaker 3: a shrimp and a ticky. Yeah, And the authors point 288 00:17:27,840 --> 00:17:31,680 Speaker 3: out that during the daytime when parrotfish are swimming around, 289 00:17:32,560 --> 00:17:35,640 Speaker 3: they actually get some help, they get some protection against 290 00:17:35,760 --> 00:17:39,159 Speaker 3: blood drinking isopods from cleaner fish. You know, this is 291 00:17:39,440 --> 00:17:42,320 Speaker 3: a relationship where a smaller fish that wants to eat. 292 00:17:42,359 --> 00:17:46,440 Speaker 3: These parasites will come along and help pick them off 293 00:17:46,560 --> 00:17:49,960 Speaker 3: to sort of groom the outside of the larger fish. 294 00:17:50,240 --> 00:17:54,240 Speaker 3: But how do the fish protect themselves at night? The 295 00:17:54,320 --> 00:17:57,600 Speaker 3: idea behind this experiment was that maybe the mucous cocoon 296 00:17:57,680 --> 00:18:01,600 Speaker 3: functions like a mosquito net to protect the sleeping fish 297 00:18:01,720 --> 00:18:07,080 Speaker 3: from these heimatophagous parasites. So they tested this hypothesis on 298 00:18:07,240 --> 00:18:11,960 Speaker 3: the coral reef parrotfish Chlorurus sortied us. And the way 299 00:18:11,960 --> 00:18:13,720 Speaker 3: they tested it was they got some of these fish, 300 00:18:13,760 --> 00:18:17,000 Speaker 3: they separated them into groups that would sleep with and 301 00:18:17,160 --> 00:18:20,760 Speaker 3: without the benefit of cocoons in the presence of these 302 00:18:20,840 --> 00:18:24,119 Speaker 3: isopod parasites. And actually, the way they did it was 303 00:18:24,160 --> 00:18:27,800 Speaker 3: they took a subset of cocoon fish and found a 304 00:18:27,800 --> 00:18:30,040 Speaker 3: way to sort of gently push them out of their 305 00:18:30,119 --> 00:18:35,680 Speaker 3: envelopes without waking them up. So what do they find. Yes, indeed, 306 00:18:35,760 --> 00:18:40,040 Speaker 3: the fish without the mucus bag experienced way more attacks 307 00:18:40,080 --> 00:18:43,919 Speaker 3: by parasites. How much more, Well, about ninety five percent 308 00:18:44,000 --> 00:18:47,879 Speaker 3: of the fish without cocoons were attacked by isopods and 309 00:18:47,920 --> 00:18:51,200 Speaker 3: only about ten percent of the fish with cocoons were attacked, 310 00:18:51,359 --> 00:18:53,040 Speaker 3: So huge difference. 311 00:18:53,000 --> 00:18:55,160 Speaker 2: All right, Right, So Yeah, coming back to the mosquito 312 00:18:55,240 --> 00:18:58,119 Speaker 2: net comparison, it's like, initially we looked at it and 313 00:18:58,200 --> 00:19:01,160 Speaker 2: we're like, this mosquito net must protect the sleeper from bears, 314 00:19:02,160 --> 00:19:06,280 Speaker 2: but in reality it protects them from mosquitos and similar 315 00:19:06,280 --> 00:19:07,280 Speaker 2: insects that sort. 316 00:19:07,160 --> 00:19:12,000 Speaker 3: Of thing, or maybe even something downstream from mosquitoes in 317 00:19:12,080 --> 00:19:15,560 Speaker 3: the analogy here, because the author is also investigated the 318 00:19:15,640 --> 00:19:20,200 Speaker 3: question of how energetically costly it is for the fish 319 00:19:20,240 --> 00:19:23,520 Speaker 3: to make these mucus orbs, and they calculated that it 320 00:19:23,560 --> 00:19:26,760 Speaker 3: takes about two point five percent of a fish's daily 321 00:19:27,040 --> 00:19:31,000 Speaker 3: energy budget to make the mucus bag. Now, when I 322 00:19:31,359 --> 00:19:33,600 Speaker 3: first saw that figure, I kind of thought, oh, hey, 323 00:19:33,640 --> 00:19:37,000 Speaker 3: that seems fairly cheap, only two point five percent. But 324 00:19:37,119 --> 00:19:40,040 Speaker 3: actually I was reading some news reporting on this that 325 00:19:40,160 --> 00:19:44,600 Speaker 3: quoted the lead author, Alexandra Grutter, and she framed it 326 00:19:44,640 --> 00:19:47,080 Speaker 3: a different way. She said, quote, the amount of effort 327 00:19:47,160 --> 00:19:50,080 Speaker 3: that goes into building these cocoons, which requires fish to 328 00:19:50,160 --> 00:19:52,960 Speaker 3: have developed very large glands about the size of a 329 00:19:53,080 --> 00:19:58,359 Speaker 3: quarter to produce the cocoons, is extraordinary. Parasites must exert 330 00:19:58,400 --> 00:20:01,359 Speaker 3: an enormous pressure on these fish in order for the 331 00:20:01,359 --> 00:20:04,240 Speaker 3: fish to have evolved such a specific way. Of avoiding 332 00:20:04,320 --> 00:20:07,600 Speaker 3: the parasites. So what could be so pressing? Is it 333 00:20:07,680 --> 00:20:09,720 Speaker 3: really just that you don't want to get bitten by 334 00:20:09,720 --> 00:20:13,040 Speaker 3: these isopods and have them drink some of your blood. Well, 335 00:20:13,240 --> 00:20:17,680 Speaker 3: Grutterer mentions the possibility that the blood directly lost to 336 00:20:17,720 --> 00:20:21,640 Speaker 3: the parasite might not be the only cost. These isopods 337 00:20:21,760 --> 00:20:26,920 Speaker 3: may also transmit a secondary endo parasite which lives in 338 00:20:27,000 --> 00:20:32,400 Speaker 3: the fish's blood, much like how mosquitoes transmit malaria in humans. 339 00:20:32,920 --> 00:20:36,080 Speaker 3: So the mosquitoes themselves are annoying and you don't like 340 00:20:36,119 --> 00:20:39,960 Speaker 3: the mosquitoes, but the malaria is much more concerning than 341 00:20:40,040 --> 00:20:43,440 Speaker 3: the mosquito. Malaria can be deadly. So in a similar way, 342 00:20:43,480 --> 00:20:46,800 Speaker 3: it's possible that it's worth it for these fish to 343 00:20:46,920 --> 00:20:52,640 Speaker 3: build these slimy bionets to protect themselves from blood disease. Wow, 344 00:20:53,119 --> 00:20:55,439 Speaker 3: so it seems like a good trade. You spend a 345 00:20:55,440 --> 00:20:58,920 Speaker 3: little energy to weave a slime tube before bed every 346 00:20:59,000 --> 00:21:03,640 Speaker 3: night without these tiny shrimp monsters drinking your blood possibly 347 00:21:03,680 --> 00:21:06,920 Speaker 3: giving you diseases of the blood, and it all works out. 348 00:21:07,040 --> 00:21:09,359 Speaker 3: And in fact, there was one more observation from grutter 349 00:21:09,760 --> 00:21:14,520 Speaker 3: speaking to the media that kind of maybe there's a 350 00:21:14,560 --> 00:21:18,879 Speaker 3: strategy to recoop some of that nightly cost. So Grutterer says, quote, 351 00:21:18,920 --> 00:21:22,040 Speaker 3: I have observed on occasion a fish at dawn with 352 00:21:22,080 --> 00:21:26,560 Speaker 3: what appeared to be mucus stuffed in its mouth. And 353 00:21:26,600 --> 00:21:28,639 Speaker 3: then she goes on to say she has seen other fish, 354 00:21:28,680 --> 00:21:32,480 Speaker 3: not parrotfish, but related fish that also produce mucous cocoons 355 00:21:33,720 --> 00:21:37,199 Speaker 3: pecking it at its old cocoons in the morning. So 356 00:21:37,359 --> 00:21:40,840 Speaker 3: like recooping some of that nightly cost by eating the 357 00:21:40,960 --> 00:21:42,960 Speaker 3: mucus that you created before bed. 358 00:21:43,320 --> 00:21:45,879 Speaker 2: I mean, that's just it's economically sound. It's like if 359 00:21:46,000 --> 00:21:50,600 Speaker 2: humans produce, say an ectoplasm defense shield at night, you 360 00:21:50,640 --> 00:21:53,240 Speaker 2: would want to to recoop that cost, and that might 361 00:21:53,320 --> 00:21:55,760 Speaker 2: mean consuming all that ectoplasm again and getting all that 362 00:21:56,560 --> 00:22:00,399 Speaker 2: liquid back into your body. You know. It reminds us 363 00:22:00,440 --> 00:22:04,440 Speaker 2: of other examples we've looked at in biology, such as 364 00:22:04,640 --> 00:22:08,760 Speaker 2: various reptiles that will eat their own shed skin because 365 00:22:08,920 --> 00:22:10,439 Speaker 2: you know, why waste that, you know. 366 00:22:10,600 --> 00:22:14,200 Speaker 3: YEA, so may still provide some kind of benefit against 367 00:22:14,520 --> 00:22:19,159 Speaker 3: larger macroscopic predators too. Not certain about that, but it 368 00:22:19,200 --> 00:22:21,400 Speaker 3: does seem like there's a very good case that these 369 00:22:21,480 --> 00:22:24,800 Speaker 3: mucus bags help prevent against parasite attacks. 370 00:22:24,920 --> 00:22:38,000 Speaker 2: Very fascinating, all right, and so for the rest of 371 00:22:38,040 --> 00:22:40,280 Speaker 2: the episode, we're going to turn to the world of 372 00:22:40,320 --> 00:22:45,000 Speaker 2: parrotfish reproduction and parrotfish sex. So, as we teach out 373 00:22:45,000 --> 00:22:48,040 Speaker 2: in the first episode, one of the other amazing aspects 374 00:22:48,080 --> 00:22:53,040 Speaker 2: of parrotfish biology broadly is that they change sex during 375 00:22:53,040 --> 00:22:56,520 Speaker 2: the course of a normal lifetime. That's to say, this 376 00:22:56,640 --> 00:22:59,520 Speaker 2: is not something that occurs, you know, only when certain 377 00:22:59,600 --> 00:23:03,199 Speaker 2: environments conditions are right. It occurs as part of a 378 00:23:03,320 --> 00:23:05,000 Speaker 2: normal life cycle. 379 00:23:05,119 --> 00:23:07,640 Speaker 3: And within a fairly predictable pattern, right. 380 00:23:07,760 --> 00:23:10,080 Speaker 2: That's right. Yeah, And they're going to be a couple 381 00:23:10,119 --> 00:23:12,479 Speaker 2: of exceptions. Again, as we've been distressing, there are a 382 00:23:12,600 --> 00:23:18,399 Speaker 2: number of different species of parrotfish, but still the vast 383 00:23:18,400 --> 00:23:23,520 Speaker 2: majority of them do follow this example that we're going 384 00:23:23,560 --> 00:23:29,200 Speaker 2: to be discussing. So they are proto gynos that means 385 00:23:29,240 --> 00:23:34,600 Speaker 2: female first, hermaphrodites that always turn into males if they 386 00:23:34,640 --> 00:23:37,480 Speaker 2: live long enough. So they're born female, and then at 387 00:23:37,480 --> 00:23:40,760 Speaker 2: a certain point during their development they become male and 388 00:23:40,840 --> 00:23:43,119 Speaker 2: live out the rest of their life as a male. 389 00:23:43,400 --> 00:23:45,920 Speaker 3: And this would feed back into something we talked about 390 00:23:45,920 --> 00:23:49,680 Speaker 3: in the first episode, which is sometimes difficulty in identifying 391 00:23:50,200 --> 00:23:54,200 Speaker 3: parrotfish species because they undergo these changes, and these changes 392 00:23:54,240 --> 00:23:56,840 Speaker 3: come with changes to their outer appearance. 393 00:23:57,080 --> 00:24:00,280 Speaker 2: That's right. Along the way, multiple changes in colorization take place, 394 00:24:00,680 --> 00:24:03,080 Speaker 2: some of which have to do with just aging, some 395 00:24:03,160 --> 00:24:06,240 Speaker 2: of which have to do with changing their sex, and 396 00:24:06,400 --> 00:24:11,119 Speaker 2: others that have to do with diet and other factors. 397 00:24:12,480 --> 00:24:16,199 Speaker 2: This pointed out by the National Marine Sanctuary Foundation as 398 00:24:16,200 --> 00:24:20,160 Speaker 2: some resources about the parrotfish. I also want to point 399 00:24:20,200 --> 00:24:24,719 Speaker 2: out though, that according to NAA fishery biologist Ronald J. Saals, 400 00:24:25,080 --> 00:24:28,120 Speaker 2: gonecharism has been reported for I think three species within 401 00:24:28,160 --> 00:24:30,959 Speaker 2: the parrotfish family, which is to say, there are at 402 00:24:31,040 --> 00:24:34,080 Speaker 2: least three species of parrotfish where we have the more 403 00:24:34,080 --> 00:24:38,160 Speaker 2: typical scenario of male female division as opposed to what 404 00:24:38,200 --> 00:24:47,080 Speaker 2: we predominantly see in parrotfish, which again is sequential hermaphroditism, 405 00:24:47,600 --> 00:24:51,520 Speaker 2: in which the fish are born female and then if 406 00:24:51,520 --> 00:24:54,200 Speaker 2: they live long enough, become male, live out the rest 407 00:24:54,200 --> 00:24:57,400 Speaker 2: of their life as males. And so the basic scenario 408 00:24:57,600 --> 00:25:01,399 Speaker 2: is most parrotfish are born females, continue to grow to 409 00:25:01,520 --> 00:25:06,159 Speaker 2: reproduce externally as females, generally in the harem of a 410 00:25:06,240 --> 00:25:09,760 Speaker 2: larger protective male who also tends to a grazing territory 411 00:25:10,280 --> 00:25:13,159 Speaker 2: and in time, if that female lives long enough and 412 00:25:13,240 --> 00:25:18,280 Speaker 2: grows large enough, she transitions into a larger, terminal, reproductive male. 413 00:25:18,960 --> 00:25:19,560 Speaker 3: Interesting. 414 00:25:20,160 --> 00:25:24,119 Speaker 2: Now, in general, parrotfish experience what I've seen referred to 415 00:25:24,160 --> 00:25:29,080 Speaker 2: as moderate longevity. It's going to vary depending on the 416 00:25:29,119 --> 00:25:32,960 Speaker 2: particular specimen, and I think it even the general generalities 417 00:25:33,000 --> 00:25:35,120 Speaker 2: about how long they live is going to vary. I've 418 00:25:35,160 --> 00:25:40,000 Speaker 2: seen in general parrotfish life span sited seven to ten years. 419 00:25:40,320 --> 00:25:42,840 Speaker 2: I've seen it cited as less than twenty. I've also 420 00:25:42,880 --> 00:25:46,000 Speaker 2: seen it sited as five to six. Again, we have 421 00:25:46,000 --> 00:25:47,879 Speaker 2: a number of different species we're talking about here, and 422 00:25:47,920 --> 00:25:50,920 Speaker 2: I'll throw out additional numbers for a specific species here 423 00:25:50,920 --> 00:25:53,959 Speaker 2: in a bit. We also have to remind ourselves that 424 00:25:54,000 --> 00:25:57,520 Speaker 2: these are creatures living in the ocean, and so there 425 00:25:57,520 --> 00:26:02,240 Speaker 2: are a whole number of factors, from blood diseases to parasites, 426 00:26:02,520 --> 00:26:05,399 Speaker 2: to eels trying to eat them, to human fishermen and 427 00:26:05,440 --> 00:26:06,000 Speaker 2: so forth. 428 00:26:06,160 --> 00:26:08,760 Speaker 3: It's just hard to imagine like ten straight years of 429 00:26:08,760 --> 00:26:11,440 Speaker 3: biting and scraping on rocks with your teeth. 430 00:26:11,400 --> 00:26:18,639 Speaker 2: Yeah, literally scraping by right now. Parrotfish display what is 431 00:26:18,640 --> 00:26:21,639 Speaker 2: referred to as indeterminate growth, which means that there's not 432 00:26:21,760 --> 00:26:25,000 Speaker 2: a full size growth limit. They just keep growing as 433 00:26:25,000 --> 00:26:28,600 Speaker 2: long as they're alive, and so parrotfish just continue to 434 00:26:28,640 --> 00:26:31,679 Speaker 2: grow at a consistent rate. And this is important to 435 00:26:31,720 --> 00:26:35,959 Speaker 2: consider in making sense of their sex changes because one of, 436 00:26:36,080 --> 00:26:39,919 Speaker 2: if not the primary hypotheses for why they do this, 437 00:26:39,960 --> 00:26:43,480 Speaker 2: why they evolve to do this, does relate to their size. 438 00:26:44,520 --> 00:26:47,119 Speaker 2: Maximum size Again, it's going to depend on the species. 439 00:26:47,640 --> 00:26:50,680 Speaker 2: I see ranges like one to four feet. But let's 440 00:26:50,680 --> 00:26:53,000 Speaker 2: go ahead and just talk about the biggest parrotfish just 441 00:26:53,000 --> 00:26:55,760 Speaker 2: to give us like a nice frame of reference, because 442 00:26:55,760 --> 00:26:59,000 Speaker 2: also the largest parrotfish is also pretty gnarly. 443 00:27:00,359 --> 00:27:02,600 Speaker 3: Is this the bumphead we talked about last time? 444 00:27:02,720 --> 00:27:04,639 Speaker 2: It is the bumphead, So we have a little more 445 00:27:04,680 --> 00:27:07,879 Speaker 2: on the bump edd here. The bump head, according to 446 00:27:08,480 --> 00:27:11,320 Speaker 2: the NOAA, reaches size as a four point two feet 447 00:27:11,359 --> 00:27:13,400 Speaker 2: long and up to one hundred pounds, so one hundred 448 00:27:13,440 --> 00:27:17,159 Speaker 2: and thirty centimeters forty six kilograms. And not only are 449 00:27:17,200 --> 00:27:19,960 Speaker 2: they the largest parrotfish, but they're among the largest reef fish. 450 00:27:20,080 --> 00:27:24,600 Speaker 2: Period reef environments are generally shallow and tight, so you know, 451 00:27:24,600 --> 00:27:28,600 Speaker 2: they're not inviting places for larger fish. And their namesake 452 00:27:28,720 --> 00:27:32,840 Speaker 2: bump is used like a rams horns in male to 453 00:27:32,880 --> 00:27:37,840 Speaker 2: male competitions, though females also have smaller bumps, which, of course, 454 00:27:38,200 --> 00:27:40,840 Speaker 2: if the parrotfish lives long enough, is going to grow 455 00:27:40,840 --> 00:27:42,800 Speaker 2: in size once they have changed sexes. 456 00:27:43,520 --> 00:27:46,240 Speaker 3: Okay, so these are fish that just keep growing even 457 00:27:46,280 --> 00:27:50,560 Speaker 3: though that's not necessarily the best for them in all ways, 458 00:27:50,600 --> 00:27:54,200 Speaker 3: like it might limit what coral surfaces they can access 459 00:27:54,240 --> 00:27:54,919 Speaker 3: and so forth. 460 00:27:55,119 --> 00:27:58,080 Speaker 2: Well, these guys are just bigger anyway. This is just. 461 00:27:58,280 --> 00:28:00,400 Speaker 2: But this would I guess, seem to be like the 462 00:28:00,440 --> 00:28:04,200 Speaker 2: maximum size that seems to fit into the evolutionary economy 463 00:28:04,920 --> 00:28:07,440 Speaker 2: of living around the reef. Okay, like I guess it 464 00:28:07,440 --> 00:28:10,320 Speaker 2: would be. It would be hard to argue that parrotfish 465 00:28:10,520 --> 00:28:14,000 Speaker 2: should get larger than this, because we have no living 466 00:28:14,040 --> 00:28:15,800 Speaker 2: parrotfish that get larger than this. 467 00:28:16,280 --> 00:28:16,800 Speaker 3: I see. 468 00:28:17,240 --> 00:28:21,840 Speaker 2: The market won't allow it, you know. Now, bumphead parrotfish 469 00:28:21,880 --> 00:28:24,840 Speaker 2: can live to be forty years old. I've read they 470 00:28:24,960 --> 00:28:28,160 Speaker 2: don't reach sexual maturity until five to eight years old, 471 00:28:28,480 --> 00:28:33,080 Speaker 2: and sadly their numbers are down except in protected reef environments. 472 00:28:33,600 --> 00:28:36,000 Speaker 3: So I believe, based on what I've read, these are 473 00:28:36,040 --> 00:28:38,920 Speaker 3: the ones that are classic. We talked about the different 474 00:28:38,920 --> 00:28:44,440 Speaker 3: classifications of parrotfish feeding behaviors based on like sort of 475 00:28:44,480 --> 00:28:47,400 Speaker 3: how hard they gouge the rock or the coral, and 476 00:28:47,520 --> 00:28:50,600 Speaker 3: these would be like the excavators, right, like they are 477 00:28:50,720 --> 00:28:52,200 Speaker 3: plowing into that stuff. 478 00:28:52,440 --> 00:28:54,480 Speaker 2: Yeah, these guys take the big bites. I was reading 479 00:28:54,520 --> 00:28:57,160 Speaker 2: a little bit more about this on the NOAA website 480 00:28:57,200 --> 00:28:59,160 Speaker 2: and they said that, yeah, they take out those big 481 00:28:59,200 --> 00:29:02,240 Speaker 2: bites that that also end up taking out a little 482 00:29:02,280 --> 00:29:04,160 Speaker 2: bit of live coral. But they stress that this is 483 00:29:04,160 --> 00:29:06,600 Speaker 2: still very healthy for the coral in all the ways 484 00:29:06,600 --> 00:29:09,760 Speaker 2: we already mentioned. I don't remember if we mentioned this. 485 00:29:10,520 --> 00:29:11,960 Speaker 2: I don't remember if we mentioned this or not. But 486 00:29:12,000 --> 00:29:15,360 Speaker 2: there's also the idea that they'll break down dead reef 487 00:29:15,760 --> 00:29:18,760 Speaker 2: and of course turn that into sand, dead bits and 488 00:29:18,800 --> 00:29:22,040 Speaker 2: branches that might otherwise break off in storms and damage 489 00:29:22,080 --> 00:29:23,120 Speaker 2: other parts of the reef. 490 00:29:23,680 --> 00:29:26,120 Speaker 3: Oh yeah, I see. So it's better for it to 491 00:29:26,480 --> 00:29:28,880 Speaker 3: better for this chunk to get ground up in a 492 00:29:28,960 --> 00:29:33,280 Speaker 3: parrotfish's pharyngial mill and pooped out as sand rather than 493 00:29:33,360 --> 00:29:35,680 Speaker 3: knocked off in the storm and hit some other healthy 494 00:29:35,720 --> 00:29:36,400 Speaker 3: part of the reef. 495 00:29:36,680 --> 00:29:39,520 Speaker 2: Yeah, because it's one of the interesting things at about 496 00:29:40,280 --> 00:29:44,000 Speaker 2: reef environments, and this is something you're definitely instructed about 497 00:29:44,080 --> 00:29:48,520 Speaker 2: anytime you go out and snorkel or scuba dive. Certainly 498 00:29:48,520 --> 00:29:51,640 Speaker 2: I imagine around these is that there is like a 499 00:29:51,720 --> 00:29:55,000 Speaker 2: hardness to them. Certainly they can also be very like 500 00:29:55,040 --> 00:29:57,920 Speaker 2: You certainly don't want to stand on them or walk 501 00:29:57,960 --> 00:30:00,880 Speaker 2: on them or touch them for a number reasons, because 502 00:30:02,080 --> 00:30:03,840 Speaker 2: a lot of times they can be quite harmful. You 503 00:30:03,880 --> 00:30:05,560 Speaker 2: can scrape you out, they can cut you. You don't 504 00:30:05,560 --> 00:30:08,080 Speaker 2: want any of that. But on top of that, they 505 00:30:08,080 --> 00:30:10,920 Speaker 2: can be actually quite delicate, and they can be easily broken. 506 00:30:10,960 --> 00:30:12,840 Speaker 2: And so this would be another case of where if 507 00:30:12,840 --> 00:30:15,800 Speaker 2: the parrotfish are doing their thing, that limits the amount 508 00:30:15,840 --> 00:30:19,600 Speaker 2: of damage that they're going to sustain via their own 509 00:30:20,120 --> 00:30:23,480 Speaker 2: dead parts. I see. But anyway, back to sex changes 510 00:30:23,520 --> 00:30:26,960 Speaker 2: in parrotfish in general. So, according to Jennifer Hodge, a 511 00:30:27,320 --> 00:30:30,880 Speaker 2: postdoctoral researcher in the Department of Evolution and Ecology in 512 00:30:30,920 --> 00:30:35,120 Speaker 2: the UC Davis College of Biological Sciences in twenty twenty, 513 00:30:36,800 --> 00:30:39,920 Speaker 2: the indeterminate growth factor may in fact be key. I 514 00:30:39,920 --> 00:30:43,880 Speaker 2: was reading a couple from a couple of sources. Here. 515 00:30:43,960 --> 00:30:49,000 Speaker 2: One is a UC Davis article by Andy Fell covering 516 00:30:49,160 --> 00:30:52,800 Speaker 2: her work titled male size advantage drives evolution and sex 517 00:30:52,880 --> 00:30:56,920 Speaker 2: change of sex change in refish. And then also there 518 00:30:57,000 --> 00:30:58,560 Speaker 2: is a full paper I was looking at, and this 519 00:30:58,600 --> 00:31:02,480 Speaker 2: is by Hodge at All titled Correlated Evolution of Sex 520 00:31:02,520 --> 00:31:06,800 Speaker 2: Allocation and Mating System in Rasses and Parrotfishes, published in 521 00:31:06,840 --> 00:31:09,120 Speaker 2: the American Naturalist the same year. 522 00:31:09,400 --> 00:31:13,720 Speaker 3: Okay, so how would this indeterminate growth factor affect how 523 00:31:13,920 --> 00:31:17,280 Speaker 3: sex is distributed and developed in a fish species. 524 00:31:17,680 --> 00:31:21,120 Speaker 2: It basically comes down to the fact the observation that 525 00:31:22,520 --> 00:31:26,040 Speaker 2: reproduction among parrotfish and also some of these other fish, 526 00:31:26,240 --> 00:31:30,360 Speaker 2: but for our interests here, the parrotfish is often dominated 527 00:31:30,400 --> 00:31:33,400 Speaker 2: by large males. 528 00:31:32,280 --> 00:31:35,360 Speaker 3: Meaning that like, a larger male has a better chance 529 00:31:35,400 --> 00:31:36,480 Speaker 3: of mating more. 530 00:31:37,120 --> 00:31:40,960 Speaker 2: Right, and that and that that male large males and 531 00:31:41,280 --> 00:31:45,640 Speaker 2: this would be the terminal males in parrotfish fishes. They 532 00:31:45,640 --> 00:31:48,040 Speaker 2: are the ones dominating like all of the mating. So 533 00:31:48,880 --> 00:31:51,160 Speaker 2: if you are not a large male, you are just 534 00:31:51,320 --> 00:31:55,800 Speaker 2: not going to be effective at reproduction. If you are 535 00:31:55,840 --> 00:31:59,920 Speaker 2: a small parrotfish male, your chances of passing on your 536 00:32:00,040 --> 00:32:03,360 Speaker 2: genes is rather slim. And remember the genetic mission is 537 00:32:03,400 --> 00:32:08,440 Speaker 2: to pass on your genes. Now, as a small parrotfish female, however, 538 00:32:08,600 --> 00:32:11,280 Speaker 2: it's less of an issue. You know, the bigger males 539 00:32:11,280 --> 00:32:13,680 Speaker 2: they have the advantage. They're going to form these harems. 540 00:32:14,520 --> 00:32:16,320 Speaker 2: If you are a small female, you can be part 541 00:32:16,360 --> 00:32:18,880 Speaker 2: of that harem and you are doing your reproductive part 542 00:32:19,160 --> 00:32:23,200 Speaker 2: as a parrotfish. And so that's according to this hypothesis, 543 00:32:23,280 --> 00:32:28,120 Speaker 2: this is where the evolution of sequential hermaphrotitism evolves as 544 00:32:28,120 --> 00:32:31,960 Speaker 2: a strategy by which all individuals have a better shot 545 00:32:32,040 --> 00:32:35,560 Speaker 2: at participating in reproduction. So start off small and female, 546 00:32:36,040 --> 00:32:38,600 Speaker 2: you definitely get to reproduce. And then if you live 547 00:32:38,680 --> 00:32:41,400 Speaker 2: long enough and you grow big enough, you shift to 548 00:32:41,920 --> 00:32:45,480 Speaker 2: the male sex, and then you have the size to 549 00:32:45,560 --> 00:32:50,280 Speaker 2: prove effective. You're better at controlling territory resources, harems, etc. 550 00:32:51,080 --> 00:32:55,320 Speaker 3: That's interesting, Okay, So it gives more individuals of the 551 00:32:55,360 --> 00:32:57,920 Speaker 3: species a chance to mate more often. 552 00:32:59,000 --> 00:33:01,520 Speaker 2: Yes, yeah, that's the way I understand it. And I 553 00:33:01,600 --> 00:33:06,360 Speaker 2: was looking again at the writings of in Oa's fishery 554 00:33:06,360 --> 00:33:10,480 Speaker 2: biologist Ronald J. Salce, and Salce points out that, yeah, 555 00:33:10,520 --> 00:33:15,320 Speaker 2: the largest parrotfish are always terminal males. And he points 556 00:33:15,360 --> 00:33:18,800 Speaker 2: out that the species, the various species in the genus 557 00:33:18,800 --> 00:33:23,719 Speaker 2: Scaas typically exhibit the following reproductive characteristics. So we see this, 558 00:33:23,880 --> 00:33:28,040 Speaker 2: first of all, there is this proto Guynus female. First hermaphrotitism. 559 00:33:28,480 --> 00:33:31,080 Speaker 2: There's there are breeding territories, there are harems, and there 560 00:33:31,160 --> 00:33:32,720 Speaker 2: is external fertilization. 561 00:33:33,280 --> 00:33:36,080 Speaker 3: Oh yeah, the external fertilization is a good point, because 562 00:33:36,200 --> 00:33:38,320 Speaker 3: I don't want to give the wrong idea when I 563 00:33:38,360 --> 00:33:42,000 Speaker 3: was mentioning mating that it's like, you know, the kind 564 00:33:42,040 --> 00:33:45,200 Speaker 3: of activity you might be picturing that Instead, there's a 565 00:33:45,280 --> 00:33:49,680 Speaker 3: there's an external meeting of the game meats of these animals. 566 00:33:49,400 --> 00:33:52,920 Speaker 2: Right, And I think, I don't know humans, maybe we 567 00:33:52,960 --> 00:33:55,479 Speaker 2: have a problem imagining fish sex in general. But somehow 568 00:33:55,480 --> 00:33:57,920 Speaker 2: this makes it a little easier to sort of picture 569 00:33:57,920 --> 00:34:00,120 Speaker 2: how all this is happening. I think it's all in 570 00:34:00,160 --> 00:34:03,200 Speaker 2: the open. So Suz points out though that in the 571 00:34:03,240 --> 00:34:06,160 Speaker 2: past and and and really maybe not in the two 572 00:34:06,160 --> 00:34:09,799 Speaker 2: distant past, we've had these other hypotheses that there might 573 00:34:09,840 --> 00:34:14,360 Speaker 2: be a social trigger for the change in sex. But apparently, 574 00:34:15,040 --> 00:34:18,080 Speaker 2: based on what he wrote, this hasn't necessarily been observed, 575 00:34:18,120 --> 00:34:21,239 Speaker 2: or at least not in all cases or in a 576 00:34:21,680 --> 00:34:26,480 Speaker 2: broad array of cases, because we have scenarios where large 577 00:34:26,560 --> 00:34:30,920 Speaker 2: terminal males are removed from a population, such as by fishing, 578 00:34:31,360 --> 00:34:35,080 Speaker 2: and the females don't just switch over at an earlier age, 579 00:34:35,120 --> 00:34:37,560 Speaker 2: but rather have more difficulty finding a mate. 580 00:34:38,000 --> 00:34:40,520 Speaker 3: Oh, okay, so it might be kind of baked in 581 00:34:40,560 --> 00:34:42,400 Speaker 3: that they need to reach a certain size. 582 00:34:42,800 --> 00:34:44,640 Speaker 2: Seems to be the case. Now I don't, But again 583 00:34:44,640 --> 00:34:47,239 Speaker 2: we're dealing with hypotheses here. I don't think that there 584 00:34:47,360 --> 00:34:50,719 Speaker 2: that anything is like one hundred proven out here. There's 585 00:34:50,719 --> 00:34:52,480 Speaker 2: still a lot of work that needs to be done 586 00:34:52,640 --> 00:34:54,239 Speaker 2: because a lot of it comes down to Okay, you 587 00:34:54,280 --> 00:34:58,480 Speaker 2: can have this general idea that this practice evolved because 588 00:34:59,200 --> 00:35:02,759 Speaker 2: large males don't dominate reproduction and and it makes more 589 00:35:02,800 --> 00:35:05,680 Speaker 2: sense from a reproductive standpoint start off as female and 590 00:35:05,680 --> 00:35:08,240 Speaker 2: then become male. But then what is the trigger is it? 591 00:35:08,320 --> 00:35:11,759 Speaker 2: Is it purely based on how big you grow? Or 592 00:35:12,080 --> 00:35:17,320 Speaker 2: are there environmental or social triggers? And ultimately the size 593 00:35:17,360 --> 00:35:21,200 Speaker 2: advantage explanation is just one hypothesis. Uh, there's an you know, 594 00:35:21,239 --> 00:35:24,400 Speaker 2: other hypotheses put more emphasis on possible social or in 595 00:35:24,440 --> 00:35:30,640 Speaker 2: mental environmental triggers, such as changes in population density, that 596 00:35:30,719 --> 00:35:32,719 Speaker 2: sort of thing. In the same way that we see 597 00:35:32,719 --> 00:35:36,279 Speaker 2: examples and say the world of salamanders, where you know 598 00:35:36,600 --> 00:35:38,640 Speaker 2: there are too many, or you know something goes on 599 00:35:38,760 --> 00:35:41,759 Speaker 2: demographically in a collect in a certain group, then you 600 00:35:41,800 --> 00:35:46,080 Speaker 2: may have biological changes that result. But I guess broadly 601 00:35:46,520 --> 00:35:50,200 Speaker 2: if there are very if there are social or environmental 602 00:35:50,239 --> 00:35:53,800 Speaker 2: triggers that are involved in theory, we would be able 603 00:35:54,160 --> 00:35:57,680 Speaker 2: to observe them, you know, such as response to overfishing 604 00:35:57,719 --> 00:36:00,960 Speaker 2: of large males, in response to changes in the environment, 605 00:36:01,000 --> 00:36:04,799 Speaker 2: and so forth. Now there are individual species of parrotfish 606 00:36:04,840 --> 00:36:08,560 Speaker 2: where we might see some of those like social triggers. 607 00:36:08,600 --> 00:36:11,920 Speaker 2: Perhaps I've seen discussion of the stop light parrotfish in 608 00:36:11,960 --> 00:36:17,000 Speaker 2: particular as perhaps being influenced by population density, growth and 609 00:36:17,120 --> 00:36:21,080 Speaker 2: mortality rates. So if terminal the idea here being that 610 00:36:21,160 --> 00:36:24,760 Speaker 2: it may be the case that terminal males in stop 611 00:36:24,840 --> 00:36:29,480 Speaker 2: light parrotfish populations, if they experience higher mortality rates so 612 00:36:29,520 --> 00:36:32,400 Speaker 2: more of them are dying, or if they're just smaller 613 00:36:32,440 --> 00:36:37,960 Speaker 2: overall sizes in the terminal males, then this change may 614 00:36:38,000 --> 00:36:43,160 Speaker 2: trigger earlier onset of the sex change in the female 615 00:36:43,200 --> 00:36:47,480 Speaker 2: parrotfish in that population. So, like I say, it still 616 00:36:47,680 --> 00:36:51,120 Speaker 2: would line up with this idea that this evolved because 617 00:36:51,600 --> 00:36:56,640 Speaker 2: male parrotfish, large male parrotfish dominate reproduction, but it would 618 00:36:56,640 --> 00:36:59,279 Speaker 2: maybe be a slightly different case of like what is 619 00:36:59,320 --> 00:37:04,239 Speaker 2: actually caused it based on my understanding looking at this documentation. 620 00:37:04,320 --> 00:37:06,319 Speaker 2: But I like to say, there's still I think a 621 00:37:06,320 --> 00:37:09,040 Speaker 2: lot of work going on here. Two thanks. Keep in mind, 622 00:37:09,040 --> 00:37:13,080 Speaker 2: though there is no evidence that any species of parrotfish 623 00:37:13,520 --> 00:37:18,280 Speaker 2: can undergo a sex change, reversal or a second sex change. 624 00:37:18,719 --> 00:37:23,640 Speaker 2: Like it is, it is sequential sequential hermaphroditism. So it's female, 625 00:37:23,840 --> 00:37:27,560 Speaker 2: then male. There are no known cases where a male 626 00:37:27,719 --> 00:37:30,600 Speaker 2: can then change back to female. Do to you do 627 00:37:30,680 --> 00:37:33,319 Speaker 2: to any kind of you know, social pressure, environmental or 628 00:37:33,360 --> 00:37:36,760 Speaker 2: what have you. It is female and then male and again. 629 00:37:36,840 --> 00:37:39,439 Speaker 2: Sequential hermaphroditism of one form or another can be found 630 00:37:39,440 --> 00:37:42,080 Speaker 2: in other fish. As I mentioned the ras is. Apparently 631 00:37:42,080 --> 00:37:46,080 Speaker 2: you see some version of this in some molluscs and crustaceans. Uh. 632 00:37:46,239 --> 00:37:50,560 Speaker 2: The size reproduction hypothesis is widely employed employed across the board, 633 00:37:51,200 --> 00:37:53,560 Speaker 2: but I've also seen I think the prevention of inbreeding 634 00:37:54,280 --> 00:37:57,239 Speaker 2: being brought in as another possible reason, though I'm not 635 00:37:57,280 --> 00:38:00,440 Speaker 2: sure if that really pans out, particularly with the parent fish. 636 00:38:00,760 --> 00:38:01,000 Speaker 3: Hmm. 637 00:38:01,280 --> 00:38:04,880 Speaker 2: That may just really have more to do with hermaphroditism 638 00:38:05,040 --> 00:38:08,640 Speaker 2: as a as an evolutionary trait in general. 639 00:38:09,080 --> 00:38:12,120 Speaker 3: But the sequential version you're saying, it seems that there's 640 00:38:12,160 --> 00:38:16,360 Speaker 3: a there's a similar evolutionary explanation given across these different 641 00:38:16,400 --> 00:38:18,719 Speaker 3: classes of animals, which is that it likely has to 642 00:38:18,719 --> 00:38:23,640 Speaker 3: do with a relationship between the animals size and its 643 00:38:23,800 --> 00:38:28,520 Speaker 3: likelihood of successful reproduction, yes, exactly, or specifically the size 644 00:38:28,520 --> 00:38:32,520 Speaker 3: of males and successful reproduction. Yeah, and the fact that 645 00:38:32,560 --> 00:38:33,840 Speaker 3: the animals just keep growing. 646 00:38:34,200 --> 00:38:37,040 Speaker 2: Yeah. Yeah, So it's fascinating. I yeah, this is like 647 00:38:37,120 --> 00:38:39,560 Speaker 2: a factoid about parrotfish that I'd long heard, but I'd 648 00:38:39,560 --> 00:38:42,080 Speaker 2: never really looked into it. I guess one of the 649 00:38:42,120 --> 00:38:44,040 Speaker 2: problems is when you're in the water, it's it's really 650 00:38:44,080 --> 00:38:46,400 Speaker 2: hard to research stuff. You're just like, oh, I'm going 651 00:38:46,440 --> 00:38:47,880 Speaker 2: to take your word for it, and I'm gonna I'm 652 00:38:47,920 --> 00:38:50,840 Speaker 2: gonna look at it, and then I'll try to remember 653 00:38:50,840 --> 00:38:51,640 Speaker 2: to read about it later. 654 00:39:01,520 --> 00:39:04,000 Speaker 3: Man, you would never guess that there is so much 655 00:39:04,000 --> 00:39:07,520 Speaker 3: interesting stuff about these fish just watching them scrape the rocks. 656 00:39:07,880 --> 00:39:10,960 Speaker 2: Yeah. Yeah, I mean just observing them, and I've observed 657 00:39:10,960 --> 00:39:12,359 Speaker 2: in plenty of times in the past. You know, it's 658 00:39:12,400 --> 00:39:13,960 Speaker 2: like you look at them and you're like, well, they're 659 00:39:13,960 --> 00:39:18,440 Speaker 2: a little bit goofy looking, they're beautifully colored, and then 660 00:39:18,480 --> 00:39:20,239 Speaker 2: you learn a little bit more about them, but there's still, 661 00:39:20,360 --> 00:39:22,879 Speaker 2: you know, greater depths of interest there. I guess that's 662 00:39:22,920 --> 00:39:25,480 Speaker 2: the that's the nature of most fish in the sea. 663 00:39:25,880 --> 00:39:26,960 Speaker 2: Never take them for granted. 664 00:39:27,239 --> 00:39:30,120 Speaker 3: In between recording these two episode parts, did you end 665 00:39:30,200 --> 00:39:34,959 Speaker 3: up googling more human parrotfish bites? I did. I don't 666 00:39:34,960 --> 00:39:36,640 Speaker 3: know why I did. I shouldn't have. 667 00:39:36,880 --> 00:39:37,919 Speaker 2: Why would you do that? 668 00:39:38,120 --> 00:39:40,400 Speaker 3: I don't know. I regret it. I wish I hadn't 669 00:39:40,440 --> 00:39:41,359 Speaker 3: done it. I just did. 670 00:39:42,680 --> 00:39:44,719 Speaker 2: The only thing of that nature that I did run 671 00:39:44,760 --> 00:39:47,040 Speaker 2: across is when I was looking up pictures and looking 672 00:39:47,080 --> 00:39:51,799 Speaker 2: at articles about the big boys, the bumphead parrotfish. Yeah, 673 00:39:51,880 --> 00:39:54,560 Speaker 2: is there was an image of some coral with some big, 674 00:39:54,680 --> 00:39:57,840 Speaker 2: chunky bites taken out of it, and that was pretty impressive, 675 00:39:58,520 --> 00:40:00,520 Speaker 2: and it did cross my mind. It's like that I 676 00:40:00,560 --> 00:40:03,440 Speaker 2: would not want those bites taken out of my own flesh. 677 00:40:03,640 --> 00:40:07,080 Speaker 3: Yeah, I would not want that to be my bones. Yeah. 678 00:40:07,080 --> 00:40:10,480 Speaker 3: But to emphasize yet again as we did last time, parrotfisher, 679 00:40:11,080 --> 00:40:14,560 Speaker 3: there's no indication that they're very aggressive or looking to 680 00:40:14,600 --> 00:40:18,239 Speaker 3: bite humans. That like, these stories come from people who 681 00:40:18,239 --> 00:40:20,880 Speaker 3: were getting up in the parrotfish's business. 682 00:40:20,760 --> 00:40:24,560 Speaker 2: Right, Yeah. I think I saw one account and this 683 00:40:24,680 --> 00:40:27,200 Speaker 2: is like, you know, this is I guess inherently unverified 684 00:40:27,920 --> 00:40:31,719 Speaker 2: of snorkelers or divers where someone was just sort of 685 00:40:32,440 --> 00:40:36,880 Speaker 2: casually bitten by a parrotfish. But in that thread, like 686 00:40:36,880 --> 00:40:39,319 Speaker 2: everyone was like, wow, that's weird. It's never happened to me. 687 00:40:39,520 --> 00:40:43,040 Speaker 2: So I don't know, you know, in the wild one 688 00:40:43,080 --> 00:40:47,120 Speaker 2: officer certainly possible. Who knows what that parrotfish was going 689 00:40:47,120 --> 00:40:47,680 Speaker 2: through that day? 690 00:40:48,040 --> 00:40:50,960 Speaker 3: Yeah, I guess any species of any fish could in 691 00:40:51,000 --> 00:40:54,960 Speaker 3: some case be aggressive, but it's not like generally thought like, oh, wow, 692 00:40:55,040 --> 00:40:57,839 Speaker 3: you gotta be careful, like they're they're coming for. 693 00:40:57,800 --> 00:40:59,799 Speaker 2: You, right, Yeah, I don't think they're they're coming. 694 00:41:00,480 --> 00:41:03,400 Speaker 3: Yeah, I'm just because I'm imagining so like, you know, 695 00:41:03,480 --> 00:41:06,279 Speaker 3: the James Bond villain has a pool of piranhas that 696 00:41:06,320 --> 00:41:09,200 Speaker 3: he drops his henchman into when they make a mistake, 697 00:41:09,239 --> 00:41:11,719 Speaker 3: And I'm just thinking, like, could they have gone with 698 00:41:11,760 --> 00:41:14,280 Speaker 3: a pool of parrotfish? How would that work out? Differently? 699 00:41:14,440 --> 00:41:17,360 Speaker 2: We have Cotajo Bodhi missed a bond with a fine 700 00:41:17,560 --> 00:41:22,440 Speaker 2: layer of algae coral dust. You will now drop you 701 00:41:22,680 --> 00:41:25,960 Speaker 2: into that of parrotfish. 702 00:41:26,480 --> 00:41:31,200 Speaker 3: M No, not the bump che Okay does that do 703 00:41:31,239 --> 00:41:32,240 Speaker 3: it for parrotfish? 704 00:41:32,280 --> 00:41:33,879 Speaker 2: I think it does? You know they may have more 705 00:41:33,920 --> 00:41:36,040 Speaker 2: mysteries that we didn't explore, but I think we hit 706 00:41:36,320 --> 00:41:39,600 Speaker 2: all the really interesting stuff here. But hey, if you 707 00:41:39,760 --> 00:41:44,200 Speaker 2: know of other dimensions to the parrotfish or various parrotfish 708 00:41:44,200 --> 00:41:46,840 Speaker 2: species that we didn't talk about right in, because we 709 00:41:46,840 --> 00:41:49,759 Speaker 2: would love to hear from you. Just a reminder that 710 00:41:49,840 --> 00:41:52,120 Speaker 2: Stuff to Blow your Mind here is primarily a science 711 00:41:52,120 --> 00:41:55,080 Speaker 2: and culture podcast, with core episodes on Tuesdays and Thursdays, 712 00:41:55,400 --> 00:41:58,560 Speaker 2: listener mail on Mondays, short form episode on Wednesdays, and 713 00:41:58,600 --> 00:42:00,960 Speaker 2: on Fridays. We set aside mostly concerns to just talk 714 00:42:01,000 --> 00:42:03,320 Speaker 2: about a weird film on Weird House Cinema. 715 00:42:03,520 --> 00:42:07,320 Speaker 3: Huge thanks as always to our excellent audio producer JJ Posway. 716 00:42:07,640 --> 00:42:09,200 Speaker 3: If you would like to get in touch with us 717 00:42:09,280 --> 00:42:11,800 Speaker 3: with feedback on this episode or any other, to suggest 718 00:42:11,800 --> 00:42:13,960 Speaker 3: a topic for the future, or just to say hello, 719 00:42:14,320 --> 00:42:17,080 Speaker 3: you can email us at contact at Stuff to Blow 720 00:42:17,080 --> 00:42:25,480 Speaker 3: your Mind dot com. 721 00:42:25,600 --> 00:42:28,560 Speaker 1: Stuff to Blow Your Mind is production of iHeartRadio. For 722 00:42:28,640 --> 00:42:31,399 Speaker 1: more podcasts from my Heart Radio, visit the iHeartRadio app, 723 00:42:31,560 --> 00:42:48,560 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.