WEBVTT 00:00:00.000 --> 00:00:03.399 We've all heard the joke. You know the one? The 00:00:03.399 --> 00:00:06.440 apocalypse joke. Exactly. Long after humanity 00:00:06.440 --> 00:00:09.660 is gone, long after the dust settles from whatever 00:00:09.660 --> 00:00:12.759 apocalyptic event finally does us in, the only 00:00:12.759 --> 00:00:15.820 things left, wandering the barren wasteland of 00:00:15.820 --> 00:00:19.129 Earth. will be the cockroaches. Right. It's this 00:00:19.129 --> 00:00:22.250 incredibly persistent pop culture myth. I mean, 00:00:22.269 --> 00:00:24.469 we look at a cockroach scurrying across the kitchen 00:00:24.469 --> 00:00:28.210 floor and we imagine it as this ancient, indestructible 00:00:28.210 --> 00:00:31.089 survivor, an insect that has supposedly remained 00:00:31.089 --> 00:00:34.310 completely unchanged since the literal dawn of 00:00:34.310 --> 00:00:36.869 time. You have probably pictured them surviving 00:00:36.869 --> 00:00:39.450 asteroid strikes, wandering through the feet 00:00:39.450 --> 00:00:41.369 of dinosaurs and looking exactly like they do 00:00:41.369 --> 00:00:44.179 right now. But the truth about the cockroach's 00:00:44.179 --> 00:00:46.159 family tree is far more bizarre, significantly 00:00:46.159 --> 00:00:48.780 more giant, and honestly a lot more fascinating 00:00:48.780 --> 00:00:51.539 than the static myth we've all bought into. We 00:00:51.539 --> 00:00:54.100 do have a tendency to flatten millions of years 00:00:54.100 --> 00:00:56.100 of evolutionary history into these very simple, 00:00:56.259 --> 00:00:58.939 you know, bite -sized narratives. Yeah. The idea 00:00:58.939 --> 00:01:01.719 of the unchanging ancient cockroach is arguably 00:01:01.719 --> 00:01:05.099 one of the most stubborn myths in biology. But 00:01:05.099 --> 00:01:07.920 when you dive into the actual fossil record... 00:01:08.090 --> 00:01:10.650 you don't find a static creature frozen in time 00:01:10.650 --> 00:01:13.209 no not at all you find a story of incredible 00:01:13.209 --> 00:01:16.890 dynamic transformation strange physical adaptations 00:01:16.890 --> 00:01:20.530 and deeply surprising evolutionary cousins and 00:01:20.530 --> 00:01:23.170 in a world of information overload taking the 00:01:23.170 --> 00:01:25.590 time to understand the true evolutionary history 00:01:25.590 --> 00:01:28.049 of these creatures offers a perfect lesson in 00:01:28.049 --> 00:01:30.489 why we must always question our basic assumptions 00:01:30.489 --> 00:01:32.930 absolutely it really forces us to look closer 00:01:32.930 --> 00:01:34.810 at the things we think we already know perfectly 00:01:34.810 --> 00:02:00.959 well and that is the mission of today I'm excited. 00:02:01.340 --> 00:02:03.640 Because every time I think I have a handle on 00:02:03.640 --> 00:02:07.780 how evolution works, a lineage like this. completely 00:02:07.780 --> 00:02:10.460 flips the script. The fossil record of these 00:02:10.460 --> 00:02:13.219 early insect forms, it acts as a window into 00:02:13.219 --> 00:02:16.539 an entirely different ecological world. The rochoids 00:02:16.539 --> 00:02:19.099 are the perfect guides through that ancient leaf 00:02:19.099 --> 00:02:22.680 litter, showing us how life actually adapts when 00:02:22.680 --> 00:02:25.500 the planet undergoes massive structural changes 00:02:25.500 --> 00:02:28.280 over millions of years. Okay, let's unpack this. 00:02:28.419 --> 00:02:31.490 What exactly is a rochoid? Because if you're 00:02:31.490 --> 00:02:33.669 reading up on this, you might see them referred 00:02:33.669 --> 00:02:35.610 to in different ways depending on where you look. 00:02:35.789 --> 00:02:38.409 Right. The terminology can be a bit dense. Yeah, 00:02:38.469 --> 00:02:40.530 sometimes they're called roachids or blatoids 00:02:40.530 --> 00:02:44.689 or even Eoblatodea. But for our purposes, we're 00:02:44.689 --> 00:02:46.629 going to stick with the term roachoids. That 00:02:46.629 --> 00:02:48.430 works perfectly. And when we talk about these 00:02:48.430 --> 00:02:50.909 creatures, we have to clear our minds of the 00:02:50.909 --> 00:02:53.449 bugs hiding under the refrigerator today, even 00:02:53.449 --> 00:02:55.430 if they share a passing resemblance. Exactly. 00:02:56.169 --> 00:02:58.150 To visualize the rochoid, you have to picture 00:02:58.150 --> 00:03:00.150 something that feels familiar at first glance, 00:03:00.310 --> 00:03:03.110 but reveals fundamental anatomical differences 00:03:03.110 --> 00:03:05.669 upon closer inspection. If you were looking at 00:03:05.669 --> 00:03:08.569 a fossilized rochoid, your brain would immediately 00:03:08.569 --> 00:03:12.430 register the general cockroach -like build. They 00:03:12.430 --> 00:03:15.789 possessed a large disc -like structure called 00:03:15.789 --> 00:03:18.250 a pronotum. That's the armor plate, right? The 00:03:18.250 --> 00:03:20.729 shield that covers the top of the head and thorax, 00:03:20.789 --> 00:03:23.629 giving that classic hunched look. Precisely. 00:03:23.979 --> 00:03:26.439 They had that distinct pronotum covering most 00:03:26.439 --> 00:03:29.139 of the head, paired with long antennae sweeping 00:03:29.139 --> 00:03:31.960 around to sense their environment. Okay. Their 00:03:31.960 --> 00:03:34.520 bodies were heavily flattened, which is an adaptation 00:03:34.520 --> 00:03:37.120 perfect for squeezing through tight spaces in 00:03:37.120 --> 00:03:40.060 the dense underbrush. And their legs were structurally 00:03:40.060 --> 00:03:42.819 built for rapid running. So they were fast. Very 00:03:42.819 --> 00:03:45.240 fast. Startle a rochoid, and it would sprint 00:03:45.240 --> 00:03:47.500 away into the prehistoric ferns just as quickly 00:03:47.500 --> 00:03:50.379 as a modern roach darts under a cabinet. But 00:03:50.379 --> 00:03:52.500 where paleontologists really focused their attention 00:03:52.500 --> 00:03:55.330 were... science happens is on the wings wings 00:03:55.330 --> 00:03:58.909 right they had heavy distinct dimension and specifically 00:03:58.909 --> 00:04:01.569 a highly characteristic arched vein called the 00:04:01.569 --> 00:04:04.129 cup vein let's talk about that cup vein for a 00:04:04.129 --> 00:04:06.349 second because that feels like one of those tiny 00:04:06.349 --> 00:04:10.270 details that unlocks a much bigger story it isn't 00:04:10.270 --> 00:04:13.349 just a random line on a wing no it acts as an 00:04:13.349 --> 00:04:17.100 evolutionary fingerprint Insect wings are incredibly 00:04:17.100 --> 00:04:20.000 delicate in life, but their venation patterns 00:04:20.000 --> 00:04:22.459 are remarkably durable in the fossil record. 00:04:22.600 --> 00:04:25.920 Fascinating. This specific arched cup vein gives 00:04:25.920 --> 00:04:28.579 the wing a distinct aerodynamic and structural 00:04:28.579 --> 00:04:32.610 profile. it likely added rigidity for an insect 00:04:32.610 --> 00:04:35.189 that spends most of its time scurrying under 00:04:35.189 --> 00:04:38.290 heavy, abrasive leaf litter rather than flying 00:04:38.290 --> 00:04:40.089 high in the canopy. That makes a lot of sense. 00:04:40.629 --> 00:04:42.949 Paleontologists use that specific vein structure 00:04:42.949 --> 00:04:45.310 to trace the rochoid lineage through different 00:04:45.310 --> 00:04:48.110 geological strata because it is incredibly typical 00:04:48.110 --> 00:04:51.990 of both rochoids and the wings of modern cockroaches. 00:04:52.209 --> 00:04:54.370 So they looked the part, and they clearly acted 00:04:54.370 --> 00:04:56.810 the part, operating as swift litter inhabitants. 00:04:57.689 --> 00:04:59.529 They were scurrying through the dead plant and 00:04:59.529 --> 00:05:01.670 animal matter on the forest floor, acting as 00:05:01.670 --> 00:05:03.649 the essential cleanup crew of the ancient world. 00:05:03.750 --> 00:05:06.089 Yes. But to really set the scene, we need to 00:05:06.089 --> 00:05:07.769 talk about the environment they were living in. 00:05:07.949 --> 00:05:10.790 Because we're starting way back in the Carboniferous 00:05:10.790 --> 00:05:12.970 period. You completely different Earth. Yeah. 00:05:13.230 --> 00:05:15.329 This was a time when the Earth's forests were 00:05:15.329 --> 00:05:18.870 dominated by massive, towering club mosses and 00:05:18.870 --> 00:05:21.709 ferns, and the atmosphere was supercharged with 00:05:21.709 --> 00:05:24.750 oxygen. And in that environment, things were 00:05:24.750 --> 00:05:27.079 just... built on a different scale. The scale 00:05:27.079 --> 00:05:29.120 is where the comparison to modern roaches really 00:05:29.120 --> 00:05:31.620 fractures. The Carboniferous period is famous 00:05:31.620 --> 00:05:34.079 for its giant arthropods, and the rochoids were 00:05:34.079 --> 00:05:37.129 absolutely no exception. Not at all. While many 00:05:37.129 --> 00:05:39.529 were modestly sized, some reached proportions 00:05:39.529 --> 00:05:42.110 that would be quite alarming to encounter today. 00:05:42.329 --> 00:05:45.829 We have fossil evidence of species like Progonoblatina, 00:05:46.029 --> 00:05:48.329 which also appears in the literature under the 00:05:48.329 --> 00:05:50.889 name Arcoblatina beachery, and another robust 00:05:50.889 --> 00:05:53.629 species called Nessimilacris. And how big are 00:05:53.629 --> 00:05:55.829 we talking? These specimens reached about nine 00:05:55.829 --> 00:05:58.370 centimeters in total length. Nine centimeters. 00:05:58.550 --> 00:06:00.389 Yeah. Which is about three and a half inches. 00:06:00.569 --> 00:06:02.550 I saw those measurements in the source material 00:06:02.550 --> 00:06:04.470 and honestly had to double check to make sure 00:06:04.470 --> 00:06:07.589 it wasn't a typo. It is remarkably large. You 00:06:07.589 --> 00:06:10.290 are talking about a heavily armored running insect 00:06:10.290 --> 00:06:13.509 the size of a computer mouse. Picture that bolting 00:06:13.509 --> 00:06:16.470 across the forest floor. It completely changes 00:06:16.470 --> 00:06:18.410 the predator prey dynamic of that ecosystem. 00:06:19.079 --> 00:06:21.100 It was a very different world. And we also have 00:06:21.100 --> 00:06:23.899 to factor in species like Opsium alacris. Oh, 00:06:23.899 --> 00:06:26.160 right. The wings on that one. Yes. The fossil 00:06:26.160 --> 00:06:28.459 records for this specific rochoid show wings 00:06:28.459 --> 00:06:32.319 reaching 7 .5 centimeters long. That wing length 00:06:32.319 --> 00:06:36.139 actually rivals the absolute largest modern cockroach 00:06:36.139 --> 00:06:38.540 we have on Earth today, which is Megaloblata 00:06:38.540 --> 00:06:41.420 longipennis. So these Carboniferous rochoids 00:06:41.420 --> 00:06:43.980 were pushing the absolute biological limits of 00:06:43.980 --> 00:06:46.759 that specific body plan. They were the undisputed 00:06:46.759 --> 00:06:49.019 giants of the undergrowth. Exactly. So you had 00:06:49.019 --> 00:06:52.079 these massive, fast, armored insects navigating 00:06:52.079 --> 00:06:54.600 the Paleozoic era. They have the pronotum, the 00:06:54.600 --> 00:06:56.939 flat bodies, the running legs. But here's where 00:06:56.939 --> 00:06:59.180 it gets really interesting. Okay. If they look 00:06:59.180 --> 00:07:02.000 so much like roaches and fulfill the exact same 00:07:02.000 --> 00:07:05.240 ecological niches roaches, why do paleontologists 00:07:05.240 --> 00:07:07.620 draw such a hard line? Why aren't they just classified 00:07:07.620 --> 00:07:09.639 as early cockroaches? That's the core question. 00:07:09.860 --> 00:07:11.639 The answer all comes down to their reproductive 00:07:11.639 --> 00:07:14.240 strategy. The reproductive anatomy is the defining 00:07:14.240 --> 00:07:17.540 line in the sand. This is where the rochoid diverges. 00:07:17.579 --> 00:07:20.540 drastically from any modern cockroach. Female 00:07:20.540 --> 00:07:22.959 rochoids possessed a well -developed external 00:07:22.959 --> 00:07:25.879 ovipositor. Which is essentially a biological 00:07:25.879 --> 00:07:28.439 sword attached to the abdomen. That is a very 00:07:28.439 --> 00:07:31.800 apt way to describe it. An ovipositor is an anatomical 00:07:31.800 --> 00:07:34.420 tube, quite long and rigid in these primitive 00:07:34.420 --> 00:07:36.500 insects, extending from the rear of the abdomen. 00:07:36.720 --> 00:07:38.939 And what did they do with it? Female rochoids 00:07:38.939 --> 00:07:41.500 use this specialized appendage to physically 00:07:41.500 --> 00:07:43.639 penetrate the substrate. They would literally 00:07:43.639 --> 00:07:46.839 inject their individual eggs directly into the 00:07:46.839 --> 00:07:50.079 dirt or deep into rotting wood, laying them one 00:07:50.079 --> 00:07:53.199 by one. Which is a completely alien concept if 00:07:53.199 --> 00:07:54.920 you know anything about how modern cockroaches 00:07:54.920 --> 00:07:57.819 operate. They don't have biological swords. They 00:07:57.819 --> 00:08:00.139 leave behind those highly distinct little hardened 00:08:00.139 --> 00:08:03.339 packages. Those packages are called uthaca. An 00:08:03.339 --> 00:08:06.720 uthaca is a complex, hardened egg pod. Like a 00:08:06.720 --> 00:08:09.620 little purse. Yes. Think of it as a portable 00:08:09.620 --> 00:08:12.459 biological fortress that contains multiple eggs 00:08:12.459 --> 00:08:15.180 safely sealed inside a protein -based casing. 00:08:15.699 --> 00:08:18.079 Modern cockroaches either drop this protective 00:08:18.079 --> 00:08:21.180 pod in a highly secure hidden crevice or, depending 00:08:21.180 --> 00:08:23.560 on the species, carry it around attached to their 00:08:23.560 --> 00:08:25.519 abdomen until the eggs are completely ready to 00:08:25.519 --> 00:08:27.240 hatch. And the roach hoods were just out there 00:08:27.240 --> 00:08:30.720 sticking naked eggs into the mud. If that Othopositor 00:08:30.720 --> 00:08:33.000 strategy worked for them for millions of years, 00:08:33.120 --> 00:08:35.679 and it clearly did, given how wildly successful 00:08:35.679 --> 00:08:38.110 they were in the Carboniferous, why would they 00:08:38.110 --> 00:08:40.049 ever need to evolve the utica pot in the first 00:08:40.049 --> 00:08:42.990 place? That transition represents what evolutionary 00:08:42.990 --> 00:08:46.509 biologists call a synapomorphy. A synapomorphy. 00:08:46.590 --> 00:08:49.509 Yes, a synapomorphy is a new shared evolutionary 00:08:49.509 --> 00:08:52.309 trait that definitively separates a specific 00:08:52.309 --> 00:08:55.250 group of organisms from their more primitive 00:08:55.250 --> 00:08:58.889 ancestors. The shift from laying naked, vulnerable 00:08:58.889 --> 00:09:02.370 eggs in the dirt with an ovipositor to producing 00:09:02.370 --> 00:09:06.490 a highly protective portable egg case is a monumental... 00:09:06.889 --> 00:09:09.389 evolutionary milestone. Because it protects them 00:09:09.389 --> 00:09:11.809 so much better. Exactly. It represents a fundamental 00:09:11.809 --> 00:09:14.129 upgrade in how these animals protected their 00:09:14.129 --> 00:09:17.149 next generation. In Uthaka, shields the embryos 00:09:17.149 --> 00:09:19.509 from microscopic predators, from fungal infections, 00:09:19.789 --> 00:09:23.090 from parasitic wasps, and crucially, from drying 00:09:23.090 --> 00:09:25.690 out as global climates began to shift. It makes 00:09:25.690 --> 00:09:27.769 total sense. They upgraded their evolutionary 00:09:27.769 --> 00:09:30.470 strategy from just having a robust physical defense 00:09:30.470 --> 00:09:32.950 for the adult insect to extending that armor 00:09:32.950 --> 00:09:34.870 over their unborn offspring. Beautifully put. 00:09:35.200 --> 00:09:37.379 So what does this all mean for their place on 00:09:37.379 --> 00:09:40.980 the tree of life? If these giant ovipositor -wielding 00:09:40.980 --> 00:09:44.039 insects aren't true cockroaches, what exactly 00:09:44.039 --> 00:09:46.460 is their relationship to the bugs we see today? 00:09:47.039 --> 00:09:49.299 Because for the longest time, the shorthand in 00:09:49.299 --> 00:09:51.820 the literature was just to label them Paleozoic 00:09:51.820 --> 00:09:54.299 cockroaches. If we connect this to the bigger 00:09:54.299 --> 00:09:57.320 picture, we have to look at how modern taxonomists 00:09:57.320 --> 00:10:00.539 construct evolutionary relationships. The label 00:10:00.539 --> 00:10:04.019 Paleozoic cockroaches is a misnomer that obscures 00:10:04.019 --> 00:10:07.200 the true complexity of their lineage. Rochoids 00:10:07.200 --> 00:10:09.620 are classified as a paraphyletic group. Which 00:10:09.620 --> 00:10:11.980 basically means they represent a grouping of 00:10:11.980 --> 00:10:14.559 primitive relatives, but that grouping doesn't 00:10:14.559 --> 00:10:16.360 include all the modern descendants that eventually 00:10:16.360 --> 00:10:18.899 sprang from that line. Right. It is like pointing 00:10:18.899 --> 00:10:20.840 at your great -grandparents and all their siblings 00:10:20.840 --> 00:10:23.620 in an old photograph. but explicitly leaving 00:10:23.620 --> 00:10:26.080 out all the modern kids and grandkids they produced. 00:10:26.399 --> 00:10:29.259 That captures the concept perfectly. A paraphyletic 00:10:29.259 --> 00:10:31.580 group is a highly useful category for scientists 00:10:31.580 --> 00:10:33.679 to group these primitive, structurally similar 00:10:33.679 --> 00:10:36.740 ancient animals together, but it is not a clean 00:10:36.740 --> 00:10:38.840 single branch on the tree of life that leads 00:10:38.840 --> 00:10:41.120 straight to one modern animal. Right, they're 00:10:41.120 --> 00:10:43.340 the base. They are an assemblage of early relatives, 00:10:43.620 --> 00:10:46.320 and understanding that paraphyletic nature leads 00:10:46.320 --> 00:10:48.639 us to the most spectacular revelation about the 00:10:48.639 --> 00:10:52.899 rochoids. This was the absolute aha. Moment for 00:10:52.899 --> 00:10:56.279 me. Get ready to completely rethink the insect 00:10:56.279 --> 00:10:59.559 world because rochoids do not just lead to cockroaches. 00:10:59.940 --> 00:11:03.419 The fossils from these Paleozoic strata prove 00:11:03.419 --> 00:11:06.139 that rochoids belong to the stem group of a massive 00:11:06.139 --> 00:11:08.799 super order called Dictyoptera. The Dictyoptera. 00:11:09.000 --> 00:11:11.679 And the members of that modern super order include 00:11:11.679 --> 00:11:13.679 not just the cockroaches we are familiar with, 00:11:13.759 --> 00:11:17.220 but also termites and surprisingly praying mantises. 00:11:17.700 --> 00:11:19.940 Termites and praying mantises. It's incredible. 00:11:19.980 --> 00:11:22.720 The morphological jump there is just. You look 00:11:22.720 --> 00:11:25.240 at a praying mantis, this elegant, upright visual 00:11:25.240 --> 00:11:28.139 predator with those massive compound eyes and 00:11:28.139 --> 00:11:30.700 raptorial slicing forelegs. And then you look 00:11:30.700 --> 00:11:33.279 at a termite. A very different creature. A pale, 00:11:33.340 --> 00:11:36.159 blind, soft -bodied little bug that lives in 00:11:36.159 --> 00:11:38.500 massive colonies, chewing on the wood inside 00:11:38.500 --> 00:11:41.600 your walls. To realize that, evolutionarily speaking, 00:11:41.899 --> 00:11:45.279 both of these wildly different insects are highly 00:11:45.279 --> 00:11:48.240 specialized offshoots of these ancient giant 00:11:48.240 --> 00:11:51.809 rochoids. Well, it's hard to wrap your head around. 00:11:51.970 --> 00:11:54.669 It really is. Termites are essentially just highly 00:11:54.669 --> 00:11:57.370 social cockroaches that evolved a specialized 00:11:57.370 --> 00:12:01.090 gut biome to digest wood. And mantises are predatory 00:12:01.090 --> 00:12:03.809 cousins that stood up and evolved to hunt. It 00:12:03.809 --> 00:12:05.809 completely shatters the myth of the unchanging 00:12:05.809 --> 00:12:08.110 cockroach. The rochoids were the primitive stock, 00:12:08.190 --> 00:12:10.649 the foundational blueprint. From that relatively 00:12:10.649 --> 00:12:13.809 generalized, scurrying stem group, the tree of 00:12:13.809 --> 00:12:16.169 life radiated outward in incredibly diverse, 00:12:16.330 --> 00:12:18.830 highly specialized directions. To understand 00:12:18.830 --> 00:12:20.549 how that happened, we have to clarify the actual 00:12:20.549 --> 00:12:23.090 timeline, which puts the final nail in the coffin 00:12:23.090 --> 00:12:25.529 of the pop culture myth. The dates are staggering. 00:12:25.669 --> 00:12:28.350 The Rochoids, these primitive Ophipositor -wielding 00:12:28.350 --> 00:12:30.870 ancestors, existed from the late Carboniferous 00:12:30.870 --> 00:12:32.669 all the way through the late Cretaceous period. 00:12:32.870 --> 00:12:34.889 They had an incredibly long run dominating the 00:12:34.889 --> 00:12:38.250 forest floor. They did. But here is the critical 00:12:38.250 --> 00:12:41.539 distinction that debunks the myth. Modern cockroaches, 00:12:41.679 --> 00:12:44.340 the true Dictyopterans equipped with the Ootheca 00:12:44.340 --> 00:12:47.440 egg cases, did not even originate until much, 00:12:47.480 --> 00:12:51.179 much later. The broader ancestors of the Dictyoptera 00:12:51.179 --> 00:12:53.740 group likely appeared sometime in the early Jurassic. 00:12:54.120 --> 00:12:57.100 And the earliest definitive fossils of modern 00:12:57.100 --> 00:12:59.440 cockroaches. They don't appear in the fossil 00:12:59.440 --> 00:13:02.480 record until the late Jurassic. So to map that 00:13:02.480 --> 00:13:04.639 out visually for you, you have the giant rochoids 00:13:04.639 --> 00:13:07.519 running around the Carboniferous. Millions and 00:13:07.519 --> 00:13:10.200 millions of years pass. We move. through the 00:13:10.200 --> 00:13:13.200 Permian, into the Triassic, and finally get deep 00:13:13.200 --> 00:13:15.539 into the Jurassic, the golden age of the classic 00:13:15.539 --> 00:13:18.200 dinosaurs like Stegosaurus and Brachiosaurus. 00:13:18.460 --> 00:13:21.200 Yes. It is only then that the actual true modern 00:13:21.200 --> 00:13:23.220 cockroaches finally step onto the evolutionary 00:13:23.220 --> 00:13:25.960 stage. By the time a modern roach existed, its 00:13:25.960 --> 00:13:27.879 roachoid ancestors had already been walking the 00:13:27.879 --> 00:13:30.460 earth for tens of millions of years. The modern 00:13:30.460 --> 00:13:33.059 cockroach is absolutely not a living fossil from 00:13:33.059 --> 00:13:35.779 the dawn of time. It is a highly derived, highly 00:13:35.779 --> 00:13:38.559 evolved Jurassic upgrade of a much older, significantly 00:13:38.559 --> 00:13:41.600 more primitive design. But the story of the rochoids 00:13:41.600 --> 00:13:44.039 didn't just end the moment modern cockroaches 00:13:44.039 --> 00:13:47.019 showed up. This brings us to their final bizarre 00:13:47.019 --> 00:13:49.820 chapter, which takes place in the Cretaceous 00:13:49.820 --> 00:13:52.639 period. A fascinating era. The Cretaceous is 00:13:52.639 --> 00:13:54.779 the tail end of the age of dinosaurs, leading 00:13:54.779 --> 00:13:57.519 right up to the asteroid impact. By this time, 00:13:57.539 --> 00:14:00.039 the traditional old school rochoids were becoming 00:14:00.039 --> 00:14:03.309 rare. The modern cockroaches with their superior 00:14:03.309 --> 00:14:06.289 utica egg cases were likely outcompeting them 00:14:06.289 --> 00:14:09.129 on the ground. But some of these lingering rochoids 00:14:09.129 --> 00:14:11.190 managed to survive by taking their evolution 00:14:11.190 --> 00:14:14.269 in a radically different direction. They adapted 00:14:14.269 --> 00:14:17.389 by fundamentally changing their morphology. We 00:14:17.389 --> 00:14:19.110 know the details of this final chapter thanks 00:14:19.110 --> 00:14:21.669 to extraordinary discoveries preserved in Burmese 00:14:21.669 --> 00:14:24.590 amber from Myanmar, which dates back... roughly 00:14:24.590 --> 00:14:27.090 100 million years. Like a time capsule. Exactly. 00:14:27.330 --> 00:14:30.350 This amber gives us pristine three -dimensional 00:14:30.350 --> 00:14:33.470 snapshots of these late -stage rotoids. And what 00:14:33.470 --> 00:14:37.250 we find are species like Encephaloblata and Proceroblata. 00:14:37.450 --> 00:14:39.870 When you look at the scans of these amber fossils 00:14:39.870 --> 00:14:42.190 from the source material, they look absolutely 00:14:42.190 --> 00:14:44.990 nothing like the giant, flat, running rotoids 00:14:44.990 --> 00:14:47.149 of the Carboniferous. Not at all. They strongly 00:14:47.149 --> 00:14:49.629 deviated from that classic ground -dwelling form. 00:14:49.950 --> 00:14:53.129 They evolved long legs, different body proportions, 00:14:53.269 --> 00:14:56.669 and actually grew to resemble modern tree crickets. 00:14:56.789 --> 00:14:59.830 Yes. Why would a lineage that spent tens of millions 00:14:59.830 --> 00:15:02.990 of years perfectly adapted to scurrying flat 00:15:02.990 --> 00:15:05.990 under dead leaves suddenly evolve to mimic a 00:15:05.990 --> 00:15:08.220 tree cricket? What's fascinating here is how 00:15:08.220 --> 00:15:12.639 life responds to massive ecological shifts. Researchers 00:15:12.639 --> 00:15:15.559 attribute this drastic morphological shift to 00:15:15.559 --> 00:15:18.240 a monumental event in Earth's history known as 00:15:18.240 --> 00:15:20.639 the angiosperm terrestrial revolution. Which 00:15:20.639 --> 00:15:22.919 is the sudden explosive evolution and global 00:15:22.919 --> 00:15:25.779 spread of flowering plants. Correct. For the 00:15:25.779 --> 00:15:28.080 vast majority of Earth's history, terrestrial 00:15:28.080 --> 00:15:30.740 forests were dominated by gymnosperms, ferns, 00:15:30.740 --> 00:15:33.399 conifers, and cycads. But during the Cretaceous 00:15:33.399 --> 00:15:36.039 flowering plants, the angiosperms rapidly... 00:15:36.080 --> 00:15:38.240 evolved and began to completely take over the 00:15:38.240 --> 00:15:40.059 terrestrial world. And that changed everything. 00:15:40.320 --> 00:15:42.279 It was not just a change in the type of plants, 00:15:42.399 --> 00:15:44.559 it completely transformed the physical architecture 00:15:44.559 --> 00:15:47.860 of the forest itself. Angiosperms created entirely 00:15:47.860 --> 00:15:50.460 new habitats, complex new layers of vertical 00:15:50.460 --> 00:15:53.500 canopy, broad leaves, and completely novel food 00:15:53.500 --> 00:15:56.139 sources. The environment was literally blooming 00:15:56.139 --> 00:15:58.480 and structuring itself vertically in a way it 00:15:58.480 --> 00:16:01.480 never had before. Exactly. So these atypical 00:16:01.480 --> 00:16:04.120 long -tailed rochoids realized they can't compete 00:16:04.120 --> 00:16:06.330 with the new modern... woches down in the dirt. 00:16:06.669 --> 00:16:09.529 Instead of just accepting extinction, they adapt. 00:16:10.090 --> 00:16:12.190 They move vertically. They climb up into these 00:16:12.190 --> 00:16:14.990 new flowering plants and change their physical 00:16:14.990 --> 00:16:17.690 bodies to blend into that new 3D architecture. 00:16:18.049 --> 00:16:20.509 Developing this tree cricket morphology as a 00:16:20.509 --> 00:16:23.250 direct response to the world changing around 00:16:23.250 --> 00:16:26.389 them. It is a masterclass in evolutionary plasticity. 00:16:26.490 --> 00:16:28.809 They weren't static at all. They were actively 00:16:28.809 --> 00:16:31.129 shapeshifting to exploit brand new ecological 00:16:31.129 --> 00:16:34.250 niches. It is a stunning example of evolutionary 00:16:34.250 --> 00:16:36.870 radiation. The rochoids were not simply waiting 00:16:36.870 --> 00:16:39.879 around in the leaf litter to go extinct. actively 00:16:39.879 --> 00:16:42.480 adapting to the new verticality created by the 00:16:42.480 --> 00:16:45.539 very first flowers. It proves how dynamic these 00:16:45.539 --> 00:16:48.080 ancient lineages truly were. It is genuinely 00:16:48.080 --> 00:16:49.820 mind -blowing when you step back and look at 00:16:49.820 --> 00:16:52.179 the whole picture. Let's recap this journey because 00:16:52.179 --> 00:16:54.179 we have covered an immense stretch of Earth's 00:16:54.179 --> 00:16:56.340 history today. We really have. We started with 00:16:56.340 --> 00:16:59.399 that stubborn myth of the basic, indestructible, 00:16:59.460 --> 00:17:02.539 unchanging cockroach. We completely tore that 00:17:02.539 --> 00:17:05.559 down by introducing the true ancestors, the Rochoids. 00:17:05.740 --> 00:17:08.359 These were nine -centimeter sword -laying giants 00:17:08.359 --> 00:17:11.299 sprinting through the hyper -oxygenated Carboniferous 00:17:11.299 --> 00:17:14.220 forests. The undeniable rulers of the undergrowth. 00:17:14.400 --> 00:17:17.039 We learned how they represent a vital paraphyletic 00:17:17.039 --> 00:17:19.359 stem group, branching off not just to modern 00:17:19.359 --> 00:17:21.720 roaches, but serving as the foundational blueprint 00:17:21.720 --> 00:17:24.359 for both termites and praying mantises. Yes. 00:17:24.640 --> 00:17:27.160 And finally, we saw how the last holdouts of 00:17:27.160 --> 00:17:29.880 this ancient family adapted to the sudden arrival 00:17:29.880 --> 00:17:32.990 of flowers. by turning into tree cricket lookalikes, 00:17:33.089 --> 00:17:36.049 forever trapped in 100 million year old amber. 00:17:36.210 --> 00:17:38.309 It perfectly illustrates why we must continually 00:17:38.309 --> 00:17:40.849 seek out multiple perspectives to enrich our 00:17:40.849 --> 00:17:43.710 understanding of the natural world. Nature's 00:17:43.710 --> 00:17:46.529 family tree is endlessly complex and deeply dynamic. 00:17:46.930 --> 00:17:49.849 By examining these long extinct paraphyletic 00:17:49.849 --> 00:17:52.630 groups, we gain a much richer multidimensional 00:17:52.630 --> 00:17:56.029 perspective of evolutionary biology. It shows 00:17:56.029 --> 00:17:58.369 us quite clearly that survival over deep time 00:17:58.369 --> 00:18:00.539 isn't about remaining unchanged. It is about 00:18:00.539 --> 00:18:03.460 constant, relentless adaptation to an ever -shifting 00:18:03.460 --> 00:18:05.759 environment. I know I will certainly never look 00:18:05.759 --> 00:18:08.339 at a praying mantis or a termite or even a roach 00:18:08.339 --> 00:18:10.640 on the sidewalk the same way again. They are 00:18:10.640 --> 00:18:14.079 carrying this wild, shared, ancient legacy right 00:18:14.079 --> 00:18:16.960 in front of us. This raises an important question, 00:18:17.059 --> 00:18:19.480 though, something for you to consider long after 00:18:19.480 --> 00:18:21.440 we wrap up this deep dive. Oh, I like where this 00:18:21.440 --> 00:18:24.740 is going. We discussed at length how modern cockroaches 00:18:24.740 --> 00:18:27.539 developed the uthica, that hardened, portable 00:18:27.539 --> 00:18:30.920 egg case, while their giant, extinct rochoid 00:18:30.920 --> 00:18:33.920 cousins relied on inserting bare eggs into the 00:18:33.920 --> 00:18:36.720 ground with an ovipositor. Right. when you consider 00:18:36.720 --> 00:18:39.559 the cataclysmic environmental changes that occurred 00:18:39.559 --> 00:18:41.720 at the end of the cretaceous period when the 00:18:41.720 --> 00:18:44.420 asteroid hit and so much life on earth was subsequently 00:18:44.420 --> 00:18:47.400 wiped out could the evolution of that simple 00:18:47.400 --> 00:18:50.799 protective egg purse have been the ultimate evolutionary 00:18:50.799 --> 00:18:53.799 cheat code wow was that singular reproductive 00:18:53.799 --> 00:18:57.099 innovation the exact reason modern cockroaches 00:18:57.099 --> 00:19:00.039 survived the apocalypse while their giant sword 00:19:00.039 --> 00:19:02.619 -laying ancestors faded forever into the fossil 00:19:02.619 --> 00:19:05.599 record now that is a profound thought to explore 00:19:05.599 --> 00:19:07.559 on your own. Keep questioning your assumptions, 00:19:07.799 --> 00:19:10.220 keep learning, and we will catch you on the next 00:19:10.220 --> 00:19:10.759 deep dive.