1 00:00:01,168 --> 00:00:02,301 Narrator: Ever wonder what happens 2 00:00:02,303 --> 00:00:05,404 When animals have an identity crisis? 3 00:00:05,406 --> 00:00:09,575 Nosal: How did this narwhal find itself among a bunch of belugas? 4 00:00:09,577 --> 00:00:12,511 Narrator: Or what has a 70-mile wide radar footprint? 5 00:00:12,513 --> 00:00:14,613 It's like an alien invasion. 6 00:00:14,615 --> 00:00:16,682 What on earth is going on? 7 00:00:16,684 --> 00:00:18,017 Narrator: And the answer to nature's 8 00:00:18,019 --> 00:00:19,752 Most burning question. 9 00:00:19,754 --> 00:00:21,954 What gives spiders nightmares? That does. 10 00:00:21,956 --> 00:00:24,556 ♪ 11 00:00:24,558 --> 00:00:27,326 Narrator: Nature is awe-inspiring. 12 00:00:27,328 --> 00:00:30,229 But sometimes, it just doesn't make sense. 13 00:00:30,231 --> 00:00:32,631 Man: I have never, ever seen anything like this! 14 00:00:32,633 --> 00:00:34,733 Narrator: Strange animal behavior, 15 00:00:34,735 --> 00:00:37,603 Unexpected events captured on camera. 16 00:00:37,605 --> 00:00:39,004 [ both screeching ] 17 00:00:39,006 --> 00:00:41,607 The truth behind them is astonishing. 18 00:00:41,609 --> 00:00:42,875 Man: My god! 19 00:00:42,877 --> 00:00:45,744 Narrator: Nature's greatest mysteries solved. 20 00:00:45,746 --> 00:00:48,747 -- Captions by vitac -- www.Vitac.Com 21 00:00:50,117 --> 00:00:51,283 Denver, colorado. 22 00:00:51,285 --> 00:00:55,454 October 3, 2017. 7:04 am. 23 00:00:55,456 --> 00:00:59,425 Meteorologist paul schlatter spots something weird and huge 24 00:00:59,427 --> 00:01:01,493 Over the state's capital. 25 00:01:01,495 --> 00:01:04,496 That morning, we saw a bloom erupt on radar. 26 00:01:04,498 --> 00:01:06,565 We weren't exactly sure what it was, 27 00:01:06,567 --> 00:01:09,068 But we certainly hadn't seen a pattern quite like that 28 00:01:09,070 --> 00:01:11,203 In any of our recent memories. 29 00:01:11,205 --> 00:01:13,605 Narrator: The mass is an astonishing 70 miles across 30 00:01:13,607 --> 00:01:15,674 And is moving in a northeasterly direction. 31 00:01:15,676 --> 00:01:18,243 Riskin: Weather officials are totally perplexed 32 00:01:18,245 --> 00:01:22,014 Trying to figure out what they are looking at on their radar. 33 00:01:22,016 --> 00:01:24,383 It looks like it might be a weird, strange cloud, 34 00:01:24,385 --> 00:01:26,185 But people have been paying attention to weather 35 00:01:26,187 --> 00:01:30,756 For a long time, and nobody had seen anything like this. 36 00:01:30,758 --> 00:01:32,458 Narrator: The national weather service agrees 37 00:01:32,460 --> 00:01:34,259 This is not a giant rain cloud. 38 00:01:34,261 --> 00:01:36,528 Schlatter: The radar signature could not have been 39 00:01:36,530 --> 00:01:38,397 A precipitation echo, 40 00:01:38,399 --> 00:01:40,766 Simply because the other radar easily confirmed 41 00:01:40,768 --> 00:01:43,035 That it was nothing weather-related. 42 00:01:43,037 --> 00:01:46,305 It seems a bit of a strange one, so what on earth is going on? 43 00:01:48,142 --> 00:01:52,544 Narrator: Well, storms aren't the only things radar can track. 44 00:01:52,546 --> 00:01:54,780 Animals that swarm in large enough quantities 45 00:01:54,782 --> 00:01:56,815 Can also appear on the screen. 46 00:01:56,817 --> 00:01:59,384 So this could be the emergence 47 00:01:59,386 --> 00:02:02,788 Of a giant bat colony over colorado. 48 00:02:02,790 --> 00:02:06,492 ♪ 49 00:02:06,494 --> 00:02:08,794 There are these bats in the united states 50 00:02:08,796 --> 00:02:10,362 Called the mexican free-tailed bat 51 00:02:10,364 --> 00:02:15,534 That form these really dense colonies inside caves. 52 00:02:15,536 --> 00:02:17,836 Every square foot of the cave ceiling 53 00:02:17,838 --> 00:02:20,139 Has 300 bats on it. 54 00:02:20,141 --> 00:02:22,841 It's all furry and wiggling, and that's what it's like 55 00:02:22,843 --> 00:02:25,944 During day, but then at night, they all come out 56 00:02:25,946 --> 00:02:28,881 The mouth of the cave and spread out over the countryside. 57 00:02:30,351 --> 00:02:33,118 Narrator: Schlatter confirms that bats could be visible 58 00:02:33,120 --> 00:02:35,454 On the scale seen in denver that day. 59 00:02:35,456 --> 00:02:39,024 Bats can easily have a swarm hundreds of miles across 60 00:02:39,026 --> 00:02:41,093 And they take off at sunset and they expand 61 00:02:41,095 --> 00:02:43,328 To a giant radar bloom that pretty much covers 62 00:02:43,330 --> 00:02:45,864 Most of the radar umbrella. 63 00:02:45,866 --> 00:02:49,635 Narrator: But with this theory, the timing is off. 64 00:02:49,637 --> 00:02:51,637 The one problem with that would be that bats 65 00:02:51,639 --> 00:02:54,773 Tend to roost and travel at nighttime, 66 00:02:54,775 --> 00:02:57,543 But this swarm was detected in the daytime. 67 00:03:00,281 --> 00:03:02,414 Narrator: If not bats, 68 00:03:02,416 --> 00:03:06,251 Is a more obvious flying friend the culprit? 69 00:03:06,253 --> 00:03:07,853 [ birds chirping ] 70 00:03:07,855 --> 00:03:09,254 Schlatter: It certainly could be birds, 71 00:03:09,256 --> 00:03:11,557 Because the typical pattern of birds migrating 72 00:03:11,559 --> 00:03:15,727 Is in a nice big swarm as it moves over the radar. 73 00:03:15,729 --> 00:03:19,097 Oftentimes in the morning, we'll see local flocks of birds 74 00:03:19,099 --> 00:03:20,899 Take off right around sunrise. 75 00:03:23,504 --> 00:03:25,604 Each fall and spring our radar network 76 00:03:25,606 --> 00:03:27,739 Lights up with migrating birds. 77 00:03:27,741 --> 00:03:30,475 It fills the entire central part of the united states. 78 00:03:32,646 --> 00:03:37,282 The purple martin does flock in mass formations. 79 00:03:37,284 --> 00:03:40,586 Birds are known to do that, particularly in the daytime. 80 00:03:42,122 --> 00:03:44,489 Also, birds such as starlings do create 81 00:03:44,491 --> 00:03:48,827 These very tight-knit formations of huge scale. 82 00:03:48,829 --> 00:03:50,796 Narrator: While flocks of starlings can gather 83 00:03:50,798 --> 00:03:55,000 In vast numbers, up to 100,000, even those figures 84 00:03:55,002 --> 00:03:58,370 Don't come close to what was seen in denver's skies. 85 00:04:00,574 --> 00:04:03,842 The problem is, there's really no species of bird 86 00:04:03,844 --> 00:04:07,546 That should be making a cloud that's 70 miles wide. 87 00:04:09,450 --> 00:04:11,550 Narrator: Birds are ruled out. 88 00:04:13,854 --> 00:04:16,421 Riskin: What about insects? 89 00:04:16,423 --> 00:04:19,958 There are lots of insects in colorado, 90 00:04:19,960 --> 00:04:21,560 And if enough of them get up into the air 91 00:04:21,562 --> 00:04:24,196 At the same time you could pick it up on radar. 92 00:04:26,133 --> 00:04:29,201 The plague of locusts is of biblical significance, 93 00:04:29,203 --> 00:04:30,636 But it's not just history. 94 00:04:30,638 --> 00:04:33,305 It's something that actually happens even today. 95 00:04:35,276 --> 00:04:37,409 Narrator: And it's not just locusts. 96 00:04:37,411 --> 00:04:40,912 Woman: Do y'all see this? This is so creepy. 97 00:04:40,914 --> 00:04:43,749 Oh, my god! 98 00:04:43,751 --> 00:04:45,584 Riskin: I mean, it happened in wisconsin, 99 00:04:45,586 --> 00:04:46,818 Right over the mississippi river, 100 00:04:46,820 --> 00:04:49,454 Where millions and millions of mayflies 101 00:04:49,456 --> 00:04:52,357 All emerged at the same time. 102 00:04:52,359 --> 00:04:57,796 Daly: It seems to be this huge, apocalyptic swarm. 103 00:04:57,798 --> 00:04:59,931 It's really hard to actually see what's going on 104 00:04:59,933 --> 00:05:03,335 Until you get a closer look, when you start to see 105 00:05:03,337 --> 00:05:07,039 Lots and lots of individual organisms. 106 00:05:08,876 --> 00:05:12,244 Riskin: Mayflies will just be covering cars and houses, 107 00:05:12,246 --> 00:05:15,147 And it's quite nasty, actually. 108 00:05:15,149 --> 00:05:18,250 Woman: Whoa! They're all over me. 109 00:05:19,653 --> 00:05:22,587 And the reason they're doing this is for sex. 110 00:05:22,589 --> 00:05:23,822 They're all having sex in the air 111 00:05:23,824 --> 00:05:26,258 Above the water and dropping eggs back down 112 00:05:26,260 --> 00:05:29,328 So that they can reproduce for next year. 113 00:05:29,330 --> 00:05:31,496 Narrator: However, the nearest sizable lake 114 00:05:31,498 --> 00:05:34,099 Is over 140 miles away. 115 00:05:34,101 --> 00:05:36,902 Mayflies hatch from large bodies of water, 116 00:05:36,904 --> 00:05:38,437 And there in denver, there aren't 117 00:05:38,439 --> 00:05:40,172 These large bodies of water to be able 118 00:05:40,174 --> 00:05:43,175 To make this a plausible explanation. 119 00:05:45,746 --> 00:05:48,180 Narrator: No water, no mayflies. 120 00:05:48,182 --> 00:05:51,950 But another winged insect might be the cause. 121 00:05:51,952 --> 00:05:53,819 Riskin: It could be a butterfly. 122 00:05:53,821 --> 00:05:55,620 There are butterflies that migrate, 123 00:05:55,622 --> 00:05:57,389 Like the monarch butterfly. 124 00:05:57,391 --> 00:06:03,495 ♪ 125 00:06:03,497 --> 00:06:05,797 Daly: Monarch butterflies are very unique. 126 00:06:05,799 --> 00:06:07,632 They are one of the few butterflies 127 00:06:07,634 --> 00:06:09,735 That actually can't survive winter. 128 00:06:09,737 --> 00:06:12,104 So they pick up on environmental cues 129 00:06:12,106 --> 00:06:15,340 To start a migration to warmer climates. 130 00:06:17,678 --> 00:06:19,845 Riskin: Monarch butterflies are amazing. 131 00:06:19,847 --> 00:06:22,147 Every fall, a butterfly will fly 132 00:06:22,149 --> 00:06:25,951 All the way from canada, all the way down north america 133 00:06:25,953 --> 00:06:28,220 All the way to mexico to get to 134 00:06:28,222 --> 00:06:30,856 This one little patch of forest for the winter. 135 00:06:32,359 --> 00:06:34,493 It's ridiculous, it shouldn't be possible, 136 00:06:34,495 --> 00:06:35,994 And yet, they do it. 137 00:06:37,965 --> 00:06:39,865 There's recent research that shows 138 00:06:39,867 --> 00:06:41,933 That they actually create their own little microclimates 139 00:06:41,935 --> 00:06:44,903 That keep them safe. 140 00:06:44,905 --> 00:06:46,571 Narrator: As a group, they can maintain 141 00:06:46,573 --> 00:06:49,641 A more constant temperature, surviving the winter 142 00:06:49,643 --> 00:06:53,512 Before taking on the 3,000 mile journey north. 143 00:06:53,514 --> 00:06:56,047 Riskin: The even weirder part is the trip back, 144 00:06:56,049 --> 00:06:58,750 Because the ones that leave mexico go a little ways, 145 00:06:58,752 --> 00:07:01,186 They stop, they have babies, those ones come out 146 00:07:01,188 --> 00:07:03,121 Of their cocoons and fly a little ways, 147 00:07:03,123 --> 00:07:05,991 And this goes five generations before they make it back. 148 00:07:05,993 --> 00:07:11,263 And then the fall, those adults fly it in one fell swoop. 149 00:07:11,265 --> 00:07:15,500 It is not normal for an insect to be able to migrate that far. 150 00:07:15,502 --> 00:07:17,602 Monarch butterflies are ridiculous. 151 00:07:17,604 --> 00:07:24,342 ♪ 152 00:07:24,344 --> 00:07:27,446 However, butterfly expert mary ann colley 153 00:07:27,448 --> 00:07:31,116 Is not convinced that monarchs are what appeared on the radar. 154 00:07:31,118 --> 00:07:34,786 Monarch migration generally happens further east 155 00:07:34,788 --> 00:07:36,521 Than the rocky mountains, 156 00:07:36,523 --> 00:07:39,357 And so denver metropolitan area 157 00:07:39,359 --> 00:07:42,561 Is not a primary flyway for the monarch migration. 158 00:07:44,364 --> 00:07:46,865 Narrator: With denver not on the monarch super highway, 159 00:07:46,867 --> 00:07:49,568 They're struck off the suspect list. 160 00:07:49,570 --> 00:07:52,471 So could the swarm that we're seeing on the radar 161 00:07:52,473 --> 00:07:54,906 Be caused by the weather after all? 162 00:07:54,908 --> 00:07:57,742 Super weird, but I think that might be it. 163 00:07:57,744 --> 00:08:00,245 ♪ 164 00:08:06,487 --> 00:08:09,187 ♪ 165 00:08:09,189 --> 00:08:10,489 Narrator: Denver, colorado. 166 00:08:10,491 --> 00:08:13,091 October 3, 2017. 167 00:08:13,093 --> 00:08:16,828 A mysterious, 70-mile wide mass has appeared on radar. 168 00:08:16,830 --> 00:08:18,730 Experts don't think it's a storm, 169 00:08:18,732 --> 00:08:22,367 Or any kind of animal swarm that they've seen before. 170 00:08:22,369 --> 00:08:24,536 Stumped for an answer, the weather service 171 00:08:24,538 --> 00:08:27,572 Puts out a call for witnesses. 172 00:08:27,574 --> 00:08:31,276 We solved the mystery using social media 173 00:08:31,278 --> 00:08:34,145 When our followers started tweeting in images 174 00:08:34,147 --> 00:08:36,815 Of butterflies just covering their yards. 175 00:08:38,785 --> 00:08:42,153 There was numerous accounts of not the monarch butterfly, 176 00:08:42,155 --> 00:08:45,757 But instead, its relative, the painted lady. 177 00:08:45,759 --> 00:08:48,627 Narrator: These butterflies have the same coloring as monarchs 178 00:08:48,629 --> 00:08:51,596 And also migrate. 179 00:08:51,598 --> 00:08:56,334 Their numbers were supersized by an unusually warm fall. 180 00:08:56,336 --> 00:08:58,503 The painted ladies had the opportunity 181 00:08:58,505 --> 00:09:00,605 To take advantage of our weather. 182 00:09:00,607 --> 00:09:02,941 We still had hundreds of thousands of blooms 183 00:09:02,943 --> 00:09:05,610 For them to feast on. 184 00:09:05,612 --> 00:09:08,513 Narrator: The weather then created a butterfly bottleneck. 185 00:09:08,515 --> 00:09:10,815 There was a low pressure system in denver, 186 00:09:10,817 --> 00:09:13,818 And what that was doing was pulling butterflies 187 00:09:13,820 --> 00:09:16,221 From all areas of north america, 188 00:09:16,223 --> 00:09:17,689 And so all these butterflies 189 00:09:17,691 --> 00:09:20,158 Were actually being funneled to the area. 190 00:09:21,562 --> 00:09:24,129 Narrator: But then, one more thing led the butterflies 191 00:09:24,131 --> 00:09:27,933 To make a forced landing in denver -- the rockies. 192 00:09:27,935 --> 00:09:30,869 Riskin: So wind is pushing them up across denver, 193 00:09:30,871 --> 00:09:32,370 And they would have kept going 194 00:09:32,372 --> 00:09:33,905 Except that there's a whole bunch of mountains there, 195 00:09:33,907 --> 00:09:36,341 So they sort of got pushed up against that and stopped, 196 00:09:36,343 --> 00:09:38,009 And then landed, and as a result 197 00:09:38,011 --> 00:09:41,112 Denver got a beautiful display of butterflies. 198 00:09:41,114 --> 00:09:49,854 ♪ 199 00:09:49,856 --> 00:09:51,356 Narrator: Hyogo, japan. 200 00:09:51,358 --> 00:09:54,092 June 10, 2013. 201 00:09:54,094 --> 00:09:56,895 Scientist observe some very strange behavior 202 00:09:56,897 --> 00:09:59,097 In this orb weaver spider. 203 00:09:59,099 --> 00:10:01,132 This is a weird one. 204 00:10:01,134 --> 00:10:03,535 Daly: This spider is spinning a very different, 205 00:10:03,537 --> 00:10:06,104 More unusual type of web. 206 00:10:06,106 --> 00:10:07,339 Narrator: It's building a web 207 00:10:07,341 --> 00:10:09,474 That makes no sense for catching prey. 208 00:10:09,476 --> 00:10:12,444 This has to be one of the more bizarre behaviors 209 00:10:12,446 --> 00:10:14,846 I've seen across the spider world. 210 00:10:14,848 --> 00:10:18,183 Why would a spider do this weird thing? 211 00:10:18,185 --> 00:10:20,118 Narrator: The answer is way beyond 212 00:10:20,120 --> 00:10:21,853 Anything you can imagine. 213 00:10:21,855 --> 00:10:24,356 What gives spiders nightmares? That does. 214 00:10:24,358 --> 00:10:27,792 ♪ 215 00:10:27,794 --> 00:10:29,160 Narrator: The spider's web pattern 216 00:10:29,162 --> 00:10:32,097 Is usually a pretty familiar shape. 217 00:10:32,099 --> 00:10:33,932 Riskin: You have an orb weaving spider 218 00:10:33,934 --> 00:10:36,234 That's supposed to spin a web that looks like, 219 00:10:36,236 --> 00:10:38,236 You know, the cartoon spiderweb does, 220 00:10:38,238 --> 00:10:41,539 But this one doesn't do that. 221 00:10:41,541 --> 00:10:45,176 Narrator: Could it be that this is just a new web design? 222 00:10:46,947 --> 00:10:51,316 Daly: There are roughly 45,000 species of spiders. 223 00:10:51,318 --> 00:10:53,284 So it could be that this orb weaver 224 00:10:53,286 --> 00:10:55,687 Is building a new type of web. 225 00:10:55,689 --> 00:10:58,923 The web is an integral part of a spider's life, 226 00:10:58,925 --> 00:11:00,258 And of course, it's very important 227 00:11:00,260 --> 00:11:02,027 For attracting its prey. 228 00:11:02,029 --> 00:11:05,630 And different prey require different kinds of webs. 229 00:11:05,632 --> 00:11:08,600 Some spiders can make crazy traps that 230 00:11:08,602 --> 00:11:11,336 They push down on top of their prey to catch them. 231 00:11:11,338 --> 00:11:14,939 Some spiders build big, huge, tennis-racket shaped things 232 00:11:14,941 --> 00:11:16,474 So that something can fly into it. 233 00:11:16,476 --> 00:11:19,778 Some build trap doors that animals fall into. 234 00:11:22,582 --> 00:11:24,049 Narrator: The net-casting spider 235 00:11:24,051 --> 00:11:27,152 Slings her web like a spidey superhero. 236 00:11:27,154 --> 00:11:30,622 ♪ 237 00:11:30,624 --> 00:11:32,791 She throws her silk over her prey, 238 00:11:32,793 --> 00:11:35,827 And then knits it into submission. 239 00:11:35,829 --> 00:11:38,129 Riskin: Spiderwebs are incredibly versatile. 240 00:11:40,634 --> 00:11:43,301 They're incredibly strong. They're incredibly tough. 241 00:11:44,805 --> 00:11:46,337 Daly: When prey gets stuck in a web, 242 00:11:46,339 --> 00:11:48,239 It's pretty much impossible to escape, 243 00:11:48,241 --> 00:11:50,642 And at that moment, the spider strikes, 244 00:11:50,644 --> 00:11:52,944 Injects venom, and eats it alive. 245 00:11:56,049 --> 00:11:59,551 Riskin: Spiderwebs are the most incredible things in nature, 246 00:11:59,553 --> 00:12:01,052 But I think the best thing about spiderwebs 247 00:12:01,054 --> 00:12:03,154 Is that they come out of a spider's butt. 248 00:12:04,191 --> 00:12:05,990 Narrator: So could our orb weaver, 249 00:12:05,992 --> 00:12:08,927 Who relies solely on its web to survive, 250 00:12:08,929 --> 00:12:12,030 Be an innovator of spider silk engineering? 251 00:12:12,032 --> 00:12:13,498 Our experts think not. 252 00:12:13,500 --> 00:12:16,401 This spider's web is not suitable for catching prey. 253 00:12:16,403 --> 00:12:18,203 Something else is going on. 254 00:12:18,205 --> 00:12:21,606 ♪ 255 00:12:21,608 --> 00:12:24,175 This spider might have eaten something 256 00:12:24,177 --> 00:12:27,712 That is making its brain not work all that well. 257 00:12:27,714 --> 00:12:30,482 Narrator: If so, it wouldn't be the first time. 258 00:12:30,484 --> 00:12:32,217 Riskin: There are some experiments that were done 259 00:12:32,219 --> 00:12:36,354 On giving drugs to spiders to see what will happen to them. 260 00:12:36,356 --> 00:12:39,491 There's evidence that when you give lsd to a spider, 261 00:12:39,493 --> 00:12:42,360 It makes a very weird web. 262 00:12:42,362 --> 00:12:44,829 Daly: Spiders that have ingested caffeine, 263 00:12:44,831 --> 00:12:48,133 Well, they create badly made webs. 264 00:12:48,135 --> 00:12:50,235 Whereas webs exposed to pesticides 265 00:12:50,237 --> 00:12:52,370 Will be eaten by spiders to get rid of them, 266 00:12:52,372 --> 00:12:54,072 So that they can build a new one. 267 00:12:55,408 --> 00:12:57,642 However, in this case, there was no evidence 268 00:12:57,644 --> 00:13:00,945 That these webs were exposed to pesticides or lsd. 269 00:13:02,516 --> 00:13:06,284 Narrator: But color footage of the spider reveals a clue. 270 00:13:06,286 --> 00:13:10,021 That little weird thing on the spider's back. 271 00:13:10,023 --> 00:13:12,857 Sounds far-fetched, but is it possible that 272 00:13:12,859 --> 00:13:17,128 This spider's mind is being controlled by someone else? 273 00:13:17,130 --> 00:13:19,564 ♪ 274 00:13:25,806 --> 00:13:28,406 ♪ 275 00:13:28,408 --> 00:13:32,110 Narrator: A japanese orb weaving spider is acting strange, 276 00:13:32,112 --> 00:13:35,880 Dismantling its web and building something else. 277 00:13:35,882 --> 00:13:38,183 It kind of looks like a cocoon, 278 00:13:38,185 --> 00:13:40,685 And spiders don't make cocoons. 279 00:13:40,687 --> 00:13:43,154 Narrator: But it's the yellow object on the spider's back 280 00:13:43,156 --> 00:13:44,389 That's the giveaway. 281 00:13:44,391 --> 00:13:47,759 ♪ 282 00:13:47,761 --> 00:13:51,262 Riskin: It turns out that little thing on its back is a maggot. 283 00:13:51,264 --> 00:13:52,964 And it's not just any maggot, 284 00:13:52,966 --> 00:13:55,700 It's the maggot of a parasitoid wasp. 285 00:13:55,702 --> 00:14:00,238 And what they do is lay an egg on a victim insect, 286 00:14:00,240 --> 00:14:04,042 Or a spider in this case, and then as that egg hatches 287 00:14:04,044 --> 00:14:08,279 And turns into a maggot, they eat the victim alive. 288 00:14:08,281 --> 00:14:10,215 Narrator: But this parasitic wasp maggot 289 00:14:10,217 --> 00:14:12,650 Isn't just eating the spider -- 290 00:14:12,652 --> 00:14:15,587 It's taking control of its brain. 291 00:14:15,589 --> 00:14:19,657 This is a fascinating example of host manipulation. 292 00:14:19,659 --> 00:14:23,061 So the wasp larvae will start to secrete these chemicals 293 00:14:23,063 --> 00:14:26,197 Which essentially control the behavior of the spider. 294 00:14:26,199 --> 00:14:28,900 So what's actually happening here is that the spider 295 00:14:28,902 --> 00:14:31,169 Is being controlled by another animal. 296 00:14:31,171 --> 00:14:32,337 Riskin: So the spider's not gonna make 297 00:14:32,339 --> 00:14:34,038 The web that would help it. 298 00:14:34,040 --> 00:14:36,474 It's gonna make a weird cocoon web 299 00:14:36,476 --> 00:14:40,011 That isn't for the spider at all, it's for the maggot. 300 00:14:40,013 --> 00:14:43,581 Once that thing is built, the maggot eats the spider, 301 00:14:43,583 --> 00:14:46,584 Drops its husk to the ground, and then goes and lives 302 00:14:46,586 --> 00:14:49,120 In that little cocoon until it can grow into a wasp 303 00:14:49,122 --> 00:14:51,890 And do it again to somebody else. 304 00:14:51,892 --> 00:14:54,492 Narrator: Terrifyingly, there are over half a million 305 00:14:54,494 --> 00:14:58,696 Different species of these flying body snatchers. 306 00:14:58,698 --> 00:15:01,966 There's no end to the nasty things they do to their hosts. 307 00:15:03,136 --> 00:15:05,870 The glyptapanteles wasp lays up to 80 eggs 308 00:15:05,872 --> 00:15:07,605 Inside a caterpillar. 309 00:15:07,607 --> 00:15:11,109 Two weeks later, they erupt out like a scene from "alien." 310 00:15:12,479 --> 00:15:17,115 So any time you see a wasp dragging a live creature around, 311 00:15:17,117 --> 00:15:20,251 It's likely a parasite that's injecting an egg 312 00:15:20,253 --> 00:15:24,555 Into its victim, turning it into a zombie slave. 313 00:15:24,557 --> 00:15:27,258 Predators aren't scary. Parasites are scary. 314 00:15:27,260 --> 00:15:30,828 And this spider has a parasite that is terrifying. 315 00:15:30,830 --> 00:15:36,868 ♪ 316 00:15:36,870 --> 00:15:38,703 Narrator: St. Lawrence river, canada. 317 00:15:38,705 --> 00:15:41,272 July 2018. 318 00:15:41,274 --> 00:15:43,841 The gremm conservation group are conducting research 319 00:15:43,843 --> 00:15:46,611 When they make an unusual sighting. 320 00:15:46,613 --> 00:15:48,980 Nosal: There's a pod of about a dozen beluga whales 321 00:15:48,982 --> 00:15:51,082 Swimming along, but on closer inspection 322 00:15:51,084 --> 00:15:53,451 One of the belugas looks a little different. 323 00:15:53,453 --> 00:15:56,955 It's not as white, and it has a long tusk sticking out of it. 324 00:15:56,957 --> 00:15:59,324 Narrator: It turns out the creature swimming with the belugas 325 00:15:59,326 --> 00:16:02,326 Is the so-called unicorn of the sea. 326 00:16:02,328 --> 00:16:05,830 Cooke: So of all the species of whales and dolphins out there, 327 00:16:05,832 --> 00:16:09,467 There is only one that has an extraordinary long tusk, 328 00:16:09,469 --> 00:16:10,868 And that's the narwhal. 329 00:16:12,205 --> 00:16:14,872 Narwhals originally were thought to be mythical creatures. 330 00:16:14,874 --> 00:16:17,408 They didn't even know that they existed until they were 331 00:16:17,410 --> 00:16:19,877 First recorded as a species in the 16th century. 332 00:16:19,879 --> 00:16:22,714 And its tusk is not like a horn 333 00:16:22,716 --> 00:16:26,117 That you might associate with other kinds of mammals. 334 00:16:26,119 --> 00:16:30,521 It's actually an elongated canine tooth. 335 00:16:30,523 --> 00:16:32,991 Narrator: The narwhal's companions, the belugas, 336 00:16:32,993 --> 00:16:37,362 Are white whales known for their extrovert personalities... 337 00:16:37,364 --> 00:16:38,830 What a good boy! [ laughs ] 338 00:16:38,832 --> 00:16:40,531 ...And high-pitched singing, 339 00:16:40,533 --> 00:16:43,001 Giving them their nickname "canary of the sea." 340 00:16:43,003 --> 00:16:45,303 [ beluga whale singing ] 341 00:16:45,305 --> 00:16:47,739 But the narwhal is 600 miles south 342 00:16:47,741 --> 00:16:50,942 Of its normal range, and animal species normally 343 00:16:50,944 --> 00:16:55,146 Stick closely to their own kind, which begs the question... 344 00:16:55,148 --> 00:16:57,782 Why is this narwhal hanging out with these belugas? 345 00:16:57,784 --> 00:17:01,552 ♪ 346 00:17:01,554 --> 00:17:05,556 Cooke: So could this just be a one-off event? 347 00:17:05,558 --> 00:17:07,625 Maybe it's just coincidence. Maybe they just happened to be 348 00:17:07,627 --> 00:17:08,960 In the same place at the same time. 349 00:17:08,962 --> 00:17:10,361 Narrator: But the behavior of the pod 350 00:17:10,363 --> 00:17:12,563 Puts that theory in doubt. 351 00:17:12,565 --> 00:17:14,899 Nosal: This doesn't seem to just be a one-off encounter, 352 00:17:14,901 --> 00:17:17,268 Because the narwhal is doing everything it can 353 00:17:17,270 --> 00:17:19,670 To fit in with its new friends. 354 00:17:19,672 --> 00:17:22,173 Cooke: The narwhal is doing everything to join in 355 00:17:22,175 --> 00:17:24,909 With the belugas, including blowing bubbles 356 00:17:24,911 --> 00:17:28,246 Back and forth, which is typical beluga behavior. 357 00:17:28,248 --> 00:17:30,515 Nosal: And it's reciprocal. The belugas seem to be 358 00:17:30,517 --> 00:17:33,384 Treating the narwhal as if it were one of their own. 359 00:17:33,386 --> 00:17:35,119 Cooke: Which suggests the relationship 360 00:17:35,121 --> 00:17:37,588 Must be fairly well established 361 00:17:37,590 --> 00:17:40,258 And not some kind of chance encounter. 362 00:17:42,195 --> 00:17:45,863 Narrator: Could the narwhal and belugas be teaming up to hunt? 363 00:17:47,300 --> 00:17:48,499 There are plenty of examples 364 00:17:48,501 --> 00:17:50,401 Of what we call mutualism in nature, 365 00:17:50,403 --> 00:17:53,104 Where two different species live in close proximity, 366 00:17:53,106 --> 00:17:56,641 And they both benefit from living together. 367 00:17:56,643 --> 00:17:58,476 Cooke: It's not uncommon in the animal kingdom 368 00:17:58,478 --> 00:18:00,845 For different species to buddy up 369 00:18:00,847 --> 00:18:03,981 In order to be successful at finding food. 370 00:18:03,983 --> 00:18:07,251 Mongooses and hornbills actually have a relationship 371 00:18:07,253 --> 00:18:09,520 That is mutually beneficial. 372 00:18:09,522 --> 00:18:11,556 The mongooses have got their heads down, 373 00:18:11,558 --> 00:18:13,024 They're snuffling around on the ground, 374 00:18:13,026 --> 00:18:14,525 And what they don't eat, 375 00:18:14,527 --> 00:18:17,161 The hornbill will hop along behind and pick up. 376 00:18:18,565 --> 00:18:21,466 It's the hornbill's job to look out for predators, 377 00:18:21,468 --> 00:18:24,535 So they're scratching each other's backs. 378 00:18:24,537 --> 00:18:27,839 So it's possible that there's a similar relationship 379 00:18:27,841 --> 00:18:30,174 Between belugas and narwhals. 380 00:18:30,176 --> 00:18:32,110 Narrator: Maybe, but differences in their diet 381 00:18:32,112 --> 00:18:33,678 Make this a long shot. 382 00:18:33,680 --> 00:18:34,879 Conley: The reason why that probably isn't 383 00:18:34,881 --> 00:18:36,714 The most likely answer is that 384 00:18:36,716 --> 00:18:38,950 Their hunting habits are very different. 385 00:18:38,952 --> 00:18:41,185 The things that they eat aren't the same. 386 00:18:41,187 --> 00:18:44,422 Narrator: So why have these guys formed a pod? 387 00:18:44,424 --> 00:18:46,190 What's going on here, I think, 388 00:18:46,192 --> 00:18:49,560 Is an example of cross-species adoption. 389 00:18:49,562 --> 00:18:51,963 ♪ 390 00:18:58,238 --> 00:19:00,605 ♪ 391 00:19:00,607 --> 00:19:03,174 Narrator: Bizarrely, a narwhal is filmed 392 00:19:03,176 --> 00:19:05,543 Swimming with a group of beluga whales. 393 00:19:05,545 --> 00:19:10,014 So how did these two species become one pod? 394 00:19:10,016 --> 00:19:14,018 The most likely explanation is cross-species adoption. 395 00:19:14,020 --> 00:19:15,686 Cooke: Now that probably sounds a bit strange, 396 00:19:15,688 --> 00:19:18,489 The idea of one species adopting another, 397 00:19:18,491 --> 00:19:20,191 But it's not altogether uncommon, 398 00:19:20,193 --> 00:19:22,994 Especially amongst social species. 399 00:19:22,996 --> 00:19:25,062 ♪ 400 00:19:25,064 --> 00:19:27,198 Narrator: It turns out, other foster families 401 00:19:27,200 --> 00:19:29,066 Have existed in the wild. 402 00:19:31,638 --> 00:19:34,272 Cooke: There's footage of a group of sperm whales 403 00:19:34,274 --> 00:19:36,474 Adopting a deformed dolphin. 404 00:19:38,044 --> 00:19:40,978 They travel together, and you can even see 405 00:19:40,980 --> 00:19:44,549 The dolphin and the sperm whale rubbing up against each other. 406 00:19:44,551 --> 00:19:48,853 [ clicking ] 407 00:19:48,855 --> 00:19:51,789 There's also instances of red-tailed hawk chicks 408 00:19:51,791 --> 00:19:54,125 Being adopted by bald eagle mamas, 409 00:19:54,127 --> 00:19:55,660 Living with the other bald eaglets, 410 00:19:55,662 --> 00:19:58,062 And then eventually fledging the nest. 411 00:19:58,064 --> 00:20:00,865 ♪ 412 00:20:00,867 --> 00:20:02,567 Narrator: Red-tailed hawks will eventually 413 00:20:02,569 --> 00:20:04,302 Strike out on their own. 414 00:20:04,304 --> 00:20:08,873 Many whale species, however, thrive on community. 415 00:20:08,875 --> 00:20:11,976 Cooke: Company is really important for social species, 416 00:20:11,978 --> 00:20:13,711 So what I think's going on here 417 00:20:13,713 --> 00:20:17,682 Is this lonely narwhal has sought company 418 00:20:17,684 --> 00:20:20,818 With these belugas and been adopted by them. 419 00:20:20,820 --> 00:20:23,354 Narrator: And it's been working well for some time. 420 00:20:23,356 --> 00:20:27,525 This blended family were first spotted back in 2016. 421 00:20:27,527 --> 00:20:30,761 Two years later, that same narwhal 422 00:20:30,763 --> 00:20:34,232 Was still hanging out with his beluga bros. 423 00:20:34,234 --> 00:20:36,100 Narrator: Raising all kinds of new questions 424 00:20:36,102 --> 00:20:39,570 About animal impulses. 425 00:20:39,572 --> 00:20:41,939 Nosal: It wouldn't surprise me if these intelligent animals 426 00:20:41,941 --> 00:20:47,044 Felt that overarching urge to love simply out of instinct. 427 00:20:47,046 --> 00:20:48,246 So it's not surprising that they might want 428 00:20:48,248 --> 00:20:50,715 To share that affection with another whale, 429 00:20:50,717 --> 00:20:52,516 A very closely related mammal. 430 00:20:52,518 --> 00:20:55,553 Captions paid for by discovery communications