1 00:00:02,000 --> 00:00:07,000 Downloaded from YTS.MX 2 00:00:03,586 --> 00:00:08,883 NARRATOR: The great white shark, fearsome and fascinating. 3 00:00:08,000 --> 00:00:13,000 Official YIFY movies site: YTS.MX 4 00:00:09,551 --> 00:00:14,472 But is there more to these apex predators than first meets the eye? 5 00:00:15,724 --> 00:00:16,850 Two scientists... 6 00:00:17,642 --> 00:00:18,601 Sheesh! 7 00:00:18,685 --> 00:00:20,645 NARRATOR: ...with a groundbreaking theory... 8 00:00:22,605 --> 00:00:24,024 This should give us some really good data. 9 00:00:24,107 --> 00:00:25,275 RYAN: I've got a shark. 10 00:00:25,358 --> 00:00:28,403 NARRATOR: ...will launch an unprecedented investigation... 11 00:00:31,656 --> 00:00:34,117 ...to find out if these explosive hunters... 12 00:00:35,118 --> 00:00:37,537 Oh, my gosh! Yes! 13 00:00:37,620 --> 00:00:44,002 NARRATOR: ...can camouflage their skin, making them the ultimate predator. 14 00:00:50,550 --> 00:00:54,387 Armed with over 300 gnashing teeth, 15 00:00:55,513 --> 00:01:00,185 growing up to 20 feet and weighing 5,000 pounds, 16 00:01:03,897 --> 00:01:07,776 and capable of speeds of over 20 miles per hour, 17 00:01:09,861 --> 00:01:16,868 the great white shark has been the perfect predator for 12 million years. 18 00:01:21,623 --> 00:01:28,088 In Mossel Bay, South Africa, there is a great white shark hot spot. 19 00:01:29,047 --> 00:01:32,133 On any given day, we can have probably upwards 20 00:01:32,217 --> 00:01:35,637 of 50 different great white sharks that are swimming in this bay. 21 00:01:37,263 --> 00:01:39,849 My name's Ryan Johnson, I'm a shark biologist, 22 00:01:39,933 --> 00:01:41,518 based here in southern Africa. 23 00:01:41,601 --> 00:01:42,936 Two sharks here, Gibbs. 24 00:01:43,019 --> 00:01:46,940 I'm Gibbs Kuguru. I'm a shark geneticist. I'm based in the Netherlands. 25 00:01:47,023 --> 00:01:49,400 NARRATOR: Together, these scientists have developed 26 00:01:49,484 --> 00:01:54,697 a potentially game-changing theory about the ocean's most infamous predator. 27 00:01:54,781 --> 00:01:57,867 RYAN: I think myself and a lot of scientists have always been wrapped up 28 00:01:57,951 --> 00:02:02,455 in the speed, the power, the size, the strength of great white sharks. 29 00:02:02,539 --> 00:02:07,919 But as you look at them, you realize maybe there's something very subtle going on. 30 00:02:08,002 --> 00:02:11,339 And that's when we caught on to the idea that, 31 00:02:11,422 --> 00:02:14,008 "Are these sharks actually manipulating their color 32 00:02:14,092 --> 00:02:16,678 to become almost camo sharks?" 33 00:02:17,762 --> 00:02:20,515 NARRATOR: Camouflage is common among marine creatures. 34 00:02:21,182 --> 00:02:27,272 Octopuses, squids, and cuttlefish are capable of lightning-fast color shifts, 35 00:02:27,355 --> 00:02:30,942 and blending into an environment can be an advantage 36 00:02:31,025 --> 00:02:33,361 to both prey and predators. 37 00:02:34,946 --> 00:02:37,240 RYAN: All these other animals use camouflage 38 00:02:37,323 --> 00:02:40,535 and sophisticated techniques to blend into the environment. 39 00:02:40,618 --> 00:02:43,288 But sharks, that's a different story. 40 00:02:43,872 --> 00:02:46,332 NARRATOR: Great whites are varying shades of gray 41 00:02:46,416 --> 00:02:51,004 on the dorsal side of their bodies with a white belly underneath. 42 00:02:51,546 --> 00:02:57,969 This countershading helps sharks blend in, whether seen from above or below. 43 00:03:04,100 --> 00:03:09,272 But the ability of sharks to actively camouflage would be a revelation. 44 00:03:09,355 --> 00:03:12,442 The theory that great white sharks can change 45 00:03:12,525 --> 00:03:15,069 and modulate their color is the first of its kind. 46 00:03:15,153 --> 00:03:19,115 There has been some research done on smaller species of shark, 47 00:03:19,199 --> 00:03:23,203 but never in anything the size of a great white shark, 48 00:03:23,286 --> 00:03:27,373 never on a predator as famous and renowned as a great white shark. 49 00:03:27,457 --> 00:03:30,251 Now, proving it is gonna be massively challenging. 50 00:03:31,377 --> 00:03:33,546 NARRATOR: To put their theory to the test, 51 00:03:34,047 --> 00:03:38,968 Ryan and Gibbs are launching a one-of-a-kind investigation. 52 00:03:40,970 --> 00:03:43,598 GIBBS: We heard just about every fisherman's tale 53 00:03:43,681 --> 00:03:46,809 about these sharks spontaneously changing color. 54 00:03:46,893 --> 00:03:50,772 But then you look at the literature, and you find actually there's little clues 55 00:03:50,855 --> 00:03:53,399 that might show that this really is happening. 56 00:03:53,858 --> 00:03:58,780 NARRATOR: Great whites can be found in cool coastal waters around the world. 57 00:03:58,863 --> 00:04:02,909 And in South Africa, they are well documented. 58 00:04:02,992 --> 00:04:05,912 So I got these photos from my research buddy, Dylan. 59 00:04:05,995 --> 00:04:09,749 This is a massive database all through the entire South African country. 60 00:04:09,832 --> 00:04:12,335 He's matched up all these fin photos from the years. 61 00:04:12,418 --> 00:04:16,297 NARRATOR: The collection is comprised of thousands of sharks. 62 00:04:16,965 --> 00:04:19,842 Nostalgic, looking back at these old photos. 63 00:04:19,926 --> 00:04:21,135 -Yeah. You took a couple of these. -Yeah. 64 00:04:21,219 --> 00:04:25,139 NARRATOR: Key identifiers like scars and unique dorsal fins 65 00:04:25,223 --> 00:04:29,769 mean scientists can track and compare the color of individual sharks. 66 00:04:30,478 --> 00:04:33,314 RYAN: See, this one here is massively lighter than the other one. 67 00:04:33,398 --> 00:04:37,318 -This one's dark, this one's light. -NARRATOR: But the evidence is flawed. 68 00:04:37,402 --> 00:04:39,737 RYAN: Yup. This is all the same shark. 69 00:04:39,821 --> 00:04:42,448 The problem we had in trying to look at 70 00:04:42,532 --> 00:04:46,661 whether sharks are modulating their color is the databases in the past 71 00:04:46,744 --> 00:04:49,414 didn't have a frame of reference for us to be able to tell 72 00:04:49,497 --> 00:04:52,667 if this shark was actually darker or lighter. 73 00:04:53,293 --> 00:04:57,380 NARRATOR: Lighting conditions, weather, and even camera settings 74 00:04:57,463 --> 00:05:00,216 can completely change a shark's appearance. 75 00:05:00,300 --> 00:05:03,094 RYAN: If we're gonna prove that this type of color change 76 00:05:03,177 --> 00:05:07,473 is actually the shark changing color, we need some type of control. 77 00:05:07,849 --> 00:05:09,600 And that's when I came up with the color board. 78 00:05:13,187 --> 00:05:16,024 NARRATOR: The grayscale color board will be the key 79 00:05:16,107 --> 00:05:19,027 to collecting visual evidence of color change 80 00:05:19,110 --> 00:05:20,903 through a range of experiments. 81 00:05:20,987 --> 00:05:24,032 RYAN: It's impossible for us to accurately measure 82 00:05:24,115 --> 00:05:28,036 the color of a shark in the wild. That's the beauty of the color board. 83 00:05:28,119 --> 00:05:30,330 As long as I can get photographs of the color board 84 00:05:30,413 --> 00:05:33,750 and the sharks together, take it back to the computer, 85 00:05:33,833 --> 00:05:34,792 correct the colors, 86 00:05:34,876 --> 00:05:37,670 then I can find out the exact color of that shark. 87 00:05:37,754 --> 00:05:40,214 NARRATOR: These experiments should also provide clues 88 00:05:40,298 --> 00:05:43,468 to the factors that motivate camouflage. 89 00:05:43,551 --> 00:05:46,220 RYAN: There has been a few studies on captive species 90 00:05:46,304 --> 00:05:50,850 to show that sharks can change color, and that it is hormonally controlled. 91 00:05:51,225 --> 00:05:54,395 What I'm hoping to do is prove conclusively 92 00:05:54,479 --> 00:05:56,856 that great white sharks can change color 93 00:05:57,398 --> 00:06:00,735 and that it is related to certain behaviors. 94 00:06:01,444 --> 00:06:05,073 When I look at it, it's so simple, but it's actually a stroke of genius 95 00:06:05,156 --> 00:06:07,992 how this really solves the problem of, you know, 96 00:06:08,076 --> 00:06:11,037 getting this, you know, color change in view. 97 00:06:11,120 --> 00:06:12,914 I think that's the first time I've ever been called a genius. 98 00:06:13,623 --> 00:06:15,541 I'll take it because it is rare. (laughing) 99 00:06:15,625 --> 00:06:18,878 The next step is, how am I gonna get this color board 100 00:06:18,961 --> 00:06:22,256 next to the shark in these different situations? 101 00:06:22,340 --> 00:06:24,300 And that just takes a little bit of creativity. 102 00:06:27,762 --> 00:06:31,766 -So, you got that, mate? -Alright, cool, yeah. Let's get going. 103 00:06:31,849 --> 00:06:33,893 RYAN: Careful, careful, careful, careful. Keep the tension. 104 00:06:36,354 --> 00:06:37,355 GIBBS: There we go. 105 00:06:40,525 --> 00:06:42,402 It's gonna be exciting stuff. 106 00:06:42,485 --> 00:06:46,739 RYAN: One of the most important tests that we're gonna do is the breaching test. 107 00:06:53,913 --> 00:06:56,791 GIBBS: Breaching is sort of this ambush attack. 108 00:06:56,874 --> 00:06:59,335 You know, they need speed, power, stealth. 109 00:07:02,463 --> 00:07:05,758 RYAN: This is when we're gonna be able to measure the color 110 00:07:05,842 --> 00:07:09,554 of a great white shark in its ultimate hunting mode. 111 00:07:12,098 --> 00:07:16,310 NARRATOR: In the middle of Mossel Bay sits Seal Island. 112 00:07:17,854 --> 00:07:21,357 RYAN: This island is the epicenter for great white sharks in South Africa. 113 00:07:28,948 --> 00:07:33,828 NARRATOR: Every day, hundreds of fur seals swim for their lives... 114 00:07:36,747 --> 00:07:39,417 through a gauntlet of great whites. 115 00:07:39,500 --> 00:07:42,712 RYAN: The great white shark's success rate in hunting Cape fur seals 116 00:07:42,795 --> 00:07:47,049 is almost 50 percent, and that's really high for any predator. 117 00:07:48,134 --> 00:07:51,220 With these sharks, they've got very specific areas 118 00:07:51,304 --> 00:07:53,181 where they want to hunt and patrol, 119 00:07:53,264 --> 00:07:55,933 and it's usually right underneath the natural routes 120 00:07:56,017 --> 00:07:58,936 that the seals are exiting and entering the islands. 121 00:08:00,938 --> 00:08:04,317 NARRATOR: Ryan and Gibbs are towing a decoy seal 122 00:08:04,400 --> 00:08:07,612 in the hopes of encouraging sharks to breach. 123 00:08:09,530 --> 00:08:13,242 RYAN: It's about trying to capture the breaching shark 124 00:08:13,326 --> 00:08:18,080 alongside a color board and being able to measure the color of that breaching shark. 125 00:08:22,293 --> 00:08:28,132 NARRATOR: It's a quiet morning, but Seal Island rarely disappoints. 126 00:08:29,383 --> 00:08:33,638 Oh, there's a predation! Natural predation right over there! 127 00:08:35,181 --> 00:08:37,141 Oh, still going for it. 128 00:08:38,184 --> 00:08:39,143 Oh, oh! 129 00:08:40,019 --> 00:08:42,271 -GIBBS: Ho, ho! -This is hot-- Oh! 130 00:08:42,355 --> 00:08:43,523 RYAN: This, this seal is in trouble. 131 00:08:43,940 --> 00:08:45,691 GIBBS: Yeah. He's using the boat for cover. 132 00:08:45,775 --> 00:08:47,944 And even though the shark missed on that first breach, 133 00:08:48,027 --> 00:08:49,445 it scared that seal so much 134 00:08:49,529 --> 00:08:52,240 that it's now hiding around the boat, using it for cover. 135 00:08:53,115 --> 00:08:56,702 NARRATOR: The seal leads the shark right to the decoy. 136 00:08:57,453 --> 00:09:00,748 -RYAN: Woo! -GIBBS: Oh, yes! 137 00:09:02,124 --> 00:09:06,212 -Got it! Got it! -Nice one, man. 138 00:09:08,714 --> 00:09:12,927 NARRATOR: The shark and the color board are clearly in frame. 139 00:09:13,719 --> 00:09:17,014 It's the first successful breach of the experiment. 140 00:09:17,098 --> 00:09:20,309 It sends goosebumps down my spine every time. 141 00:09:20,393 --> 00:09:21,811 I mean, you just can't... 142 00:09:22,895 --> 00:09:24,981 you can't help but feel emotional every time you see it. 143 00:09:25,815 --> 00:09:27,775 NARRATOR: Sharks are here in numbers. 144 00:09:28,734 --> 00:09:29,735 GIBBS: Oh, ho! 145 00:09:29,819 --> 00:09:31,279 -RYAN: There we go! -GIBBS: There we go. 146 00:09:31,362 --> 00:09:32,905 NARRATOR: Stalking seals... 147 00:09:34,657 --> 00:09:35,575 all... 148 00:09:37,493 --> 00:09:38,536 day... 149 00:09:39,829 --> 00:09:42,039 -long. -GIBBS: It's having a go at it. 150 00:09:47,295 --> 00:09:48,379 Woo! 151 00:09:49,046 --> 00:09:52,883 NARRATOR: As the sun sets after a day of data collection, 152 00:09:52,967 --> 00:09:55,803 the team hopes for one last breach. 153 00:09:56,762 --> 00:09:58,764 RYAN: Hit that spot. Hit that spot. 154 00:10:03,144 --> 00:10:04,770 Oh, ho! 155 00:10:06,272 --> 00:10:08,524 Alright, we've lost the color board, we've lost the decoy. 156 00:10:08,899 --> 00:10:09,900 GIBBS: Dang it! 157 00:10:09,984 --> 00:10:12,403 RYAN: Because it's so dark, the shark couldn't even see which way to go. 158 00:10:12,486 --> 00:10:13,487 He's going for it again! 159 00:10:25,374 --> 00:10:28,252 NARRATOR: Sharks often hunt at twilight, 160 00:10:28,711 --> 00:10:32,673 but in the darkness, even a great white can miscalculate. 161 00:10:32,757 --> 00:10:35,384 -RYAN: Oh, oh, oh. -GIBBS: Dang it. 162 00:10:36,177 --> 00:10:38,888 RYAN: This is gonna be an issue floating again. 163 00:10:38,971 --> 00:10:42,558 NARRATOR: They'll have to rebuild before getting back on the water. 164 00:10:46,729 --> 00:10:49,982 But building their database of evidence is underway. 165 00:10:50,066 --> 00:10:52,610 RYAN: Just looking at that and comparing that to the color board. 166 00:10:53,277 --> 00:10:55,321 Right up there, isn't it? Dark. 167 00:10:55,404 --> 00:10:58,658 Science is not fast, it takes a long time, it takes a lot of data. 168 00:10:59,367 --> 00:11:00,576 -Nice. -Ooh. 169 00:11:00,660 --> 00:11:04,121 RYAN: Particularly when you're trying to rewrite a whole idea 170 00:11:04,413 --> 00:11:06,040 on a sort of scientific paradigm. 171 00:11:06,499 --> 00:11:08,209 This is money in the bank, each one of these. 172 00:11:08,834 --> 00:11:11,921 NARRATOR: But there's more to this study than meets the eye. 173 00:11:13,255 --> 00:11:15,591 RYAN: The behavior is only one side of the study. 174 00:11:15,675 --> 00:11:19,762 The cellular work is the other side, and it's equally as important. 175 00:11:20,763 --> 00:11:22,973 Yeah, it's a male. Definitely a juvenile. 176 00:11:24,183 --> 00:11:28,396 NARRATOR: Ryan and Gibbs have a rare opportunity with their investigation. 177 00:11:28,479 --> 00:11:29,563 So that's a juvenile. 178 00:11:29,647 --> 00:11:31,899 RYAN: A chance to get to work with a great white like this 179 00:11:31,982 --> 00:11:36,362 comes around, you know, once or twice in a career, for, for at least me. 180 00:11:36,445 --> 00:11:37,321 First time. 181 00:11:37,405 --> 00:11:40,783 NARRATOR: When sharks are tragically caught in fishing nets... 182 00:11:40,866 --> 00:11:41,701 RYAN: Okay, that's good. 183 00:11:41,784 --> 00:11:46,163 NARRATOR: ...scientists like Dr. Matt Dicken ensure it isn't in vain. 184 00:11:46,247 --> 00:11:47,873 MATT DICKEN: One of the things we do at the Sharks Board 185 00:11:47,957 --> 00:11:50,084 is collect as many samples as possible. 186 00:11:50,167 --> 00:11:53,587 And that really improves our knowledge and science of this incredible species. 187 00:11:53,671 --> 00:11:57,091 NARRATOR: Dissection will let the team search for vital clues 188 00:11:57,174 --> 00:12:01,178 to their color change theory, hidden in the stomach of the shark. 189 00:12:02,346 --> 00:12:04,890 The diets of great whites are seasonal 190 00:12:04,974 --> 00:12:08,185 and change as they grow larger and more powerful. 191 00:12:09,770 --> 00:12:12,690 So what and where sharks eat 192 00:12:13,774 --> 00:12:16,694 could tell us something about their need for camouflage. 193 00:12:17,278 --> 00:12:18,738 RYAN: It's quite tough, eh? 194 00:12:18,821 --> 00:12:22,366 I want this definitive proof that these great whites 195 00:12:22,450 --> 00:12:26,120 do, in fact, feed at the surface, feed mid-water, feed at the bottom. 196 00:12:26,620 --> 00:12:29,123 And this is sort of the detective work you have to play 197 00:12:29,206 --> 00:12:31,459 to actually identify what the animals are eating. 198 00:12:31,959 --> 00:12:33,669 -MATT: You know what that is? -GIBBS: No. What is it? 199 00:12:33,753 --> 00:12:35,713 -Stingray barb. -No way! 200 00:12:35,796 --> 00:12:41,302 So again, I'm thinking that actually could be the real evidence you need 201 00:12:41,385 --> 00:12:43,846 that these white sharks are feeding on the bottom. 202 00:12:43,929 --> 00:12:44,930 GIBBS: Right on. 203 00:12:45,431 --> 00:12:47,224 -Outstanding. -RYAN: Dang. 204 00:12:47,308 --> 00:12:50,895 NARRATOR: This small find proves a big point. 205 00:12:51,520 --> 00:12:55,399 The ability to adapt camouflage could be a huge advantage 206 00:12:55,483 --> 00:12:58,027 to the vastly different hunting strategies 207 00:12:58,778 --> 00:13:03,115 at the bright surface and the dark sea floor. 208 00:13:05,534 --> 00:13:07,703 RYAN: Great success with the stomach contents. 209 00:13:07,787 --> 00:13:09,538 You know, finding that evidence of the stingray 210 00:13:09,622 --> 00:13:13,083 and that the sharks do have this varied hunting behavior that we wanted. 211 00:13:13,959 --> 00:13:15,294 GIBBS: And there's a whole bunch of them, too. 212 00:13:15,795 --> 00:13:17,922 NARRATOR: But the key to proving color change 213 00:13:18,005 --> 00:13:21,842 is scientifically possible goes beyond skin deep. 214 00:13:21,926 --> 00:13:26,931 My research is based on the skin of sharks and the different adaptations they have 215 00:13:27,014 --> 00:13:29,183 that cause their skin to work in different ways. 216 00:13:30,559 --> 00:13:33,020 One of these adaptations that we think they may have 217 00:13:33,395 --> 00:13:35,022 is this ability to change color. 218 00:13:35,606 --> 00:13:37,858 We wanted to design an experiment 219 00:13:37,942 --> 00:13:40,611 that would sort of tell us if this is even possible. 220 00:13:40,778 --> 00:13:45,199 NARRATOR: The secret to color change may be hidden at the molecular level, 221 00:13:45,282 --> 00:13:48,994 with a little-known cell called a melanocyte. 222 00:13:49,078 --> 00:13:54,500 GIBBS: A melanocyte is the tissue that sort of gives rise to pigment in animals. 223 00:13:54,959 --> 00:13:58,045 It acts kind of like a circuit board underneath the skin 224 00:13:58,128 --> 00:14:03,467 where it sort of flexes and contracts based on what the animal needs. 225 00:14:04,051 --> 00:14:07,137 So let's say you have a stimulus from the sun, 226 00:14:07,888 --> 00:14:11,016 the circuit board tells your skin to go a bit darker. 227 00:14:11,767 --> 00:14:14,687 And, you know, vice versa, if you haven't seen enough sun, 228 00:14:15,104 --> 00:14:20,025 it'll cause your pigment to sort of shrink in, i.e., it goes paler. 229 00:14:20,901 --> 00:14:23,404 NARRATOR: To understand if melanocytes are present 230 00:14:23,487 --> 00:14:26,282 and capable of changing a shark's skin color, 231 00:14:26,949 --> 00:14:30,619 the team has devised a series of tests. 232 00:14:30,703 --> 00:14:32,913 GIBBS: We're gonna try and take some tissue samples 233 00:14:32,997 --> 00:14:36,584 of the skin of the shark and then expose it to some hormones 234 00:14:36,667 --> 00:14:41,380 to see if this actually does induce a color change response. 235 00:14:41,881 --> 00:14:46,218 And we're hoping that as each of these hormones interacts with the tissue, 236 00:14:46,302 --> 00:14:48,721 it actually causes them to go lighter or darker. 237 00:14:49,346 --> 00:14:51,307 NARRATOR: The hormones replicate those 238 00:14:51,390 --> 00:14:53,976 that are believed to flow through a live shark 239 00:14:54,059 --> 00:14:57,688 during behavior like hunting or resting. 240 00:14:57,771 --> 00:15:01,775 GIBBS: We do have some hypotheses for what these hormones will do. 241 00:15:01,859 --> 00:15:07,156 The first one, MSH, is actually a hormone that stimulates 242 00:15:07,239 --> 00:15:10,200 the expansion of the melanocytes 243 00:15:10,284 --> 00:15:13,245 in just about every species that has melanin. 244 00:15:13,329 --> 00:15:17,541 We have the adrenaline which has triggered a paling response 245 00:15:17,625 --> 00:15:22,671 in some sharks and has also created a darkening response in some fish. 246 00:15:22,755 --> 00:15:25,633 And then the last hormone is the melatonin. 247 00:15:26,258 --> 00:15:29,345 And we think this is definitely going to give it a paling response. 248 00:15:29,929 --> 00:15:34,350 NARRATOR: If the test works, it should change the color of the skin. 249 00:15:34,433 --> 00:15:36,185 This feels like a real moment of truth, 250 00:15:36,977 --> 00:15:39,730 seeing how these sharks actually will respond to these hormones. 251 00:15:41,857 --> 00:15:43,233 -RYAN: Ready? -GIBBS: Yup. 252 00:15:46,111 --> 00:15:49,031 NARRATOR: But the samples don't appear to be changing. 253 00:15:49,114 --> 00:15:52,743 I actually don't think that the skin is really reacting. It's... 254 00:15:53,494 --> 00:15:54,912 Looks more or less the same. 255 00:15:55,955 --> 00:15:58,874 The dead shark skin doesn't seem like it's going to work. 256 00:15:58,958 --> 00:16:03,420 I think that's just because the tissue of the shark is physiologically dead. 257 00:16:03,504 --> 00:16:08,425 So all the little biochemical pathways are totally shut down. 258 00:16:08,842 --> 00:16:10,094 This is a new experiment. 259 00:16:10,177 --> 00:16:13,722 And I think this is typical of science, that it doesn't work the first time. 260 00:16:13,806 --> 00:16:16,767 Yeah, I think Ryan and I are gonna have to tweak our methodology. 261 00:16:21,021 --> 00:16:24,358 NARRATOR: Most sharks are shades of gray or brown. 262 00:16:25,025 --> 00:16:30,656 Some, like the tiger or zebra, have distinct patterns that set them apart. 263 00:16:31,949 --> 00:16:35,869 In False Bay, South Africa, Ryan and Gibbs are looking 264 00:16:35,953 --> 00:16:42,418 for a species with an adaptation as incredible... as color change. 265 00:16:43,002 --> 00:16:45,504 GIBBS: Puffadder sharks are probably one of the most docile sharks. 266 00:16:45,587 --> 00:16:47,089 You'll oftentimes see them 267 00:16:47,172 --> 00:16:50,926 sort of nestled between two rocks or snuggling around a piece of kelp. 268 00:16:51,010 --> 00:16:52,219 So they're cute. 269 00:16:52,302 --> 00:16:54,096 They're not like a great white, that's for certain. 270 00:16:54,179 --> 00:17:01,020 But puffadder shyshark recently has been discovered to exhibit biofluorescence. 271 00:17:01,103 --> 00:17:03,689 And that means essentially it's a glow-in-the-dark type shark. 272 00:17:04,314 --> 00:17:08,652 NARRATOR: Why a shark would evolve to glow is a mystery. 273 00:17:09,361 --> 00:17:13,115 RYAN: They're incredibly camouflaged to the reefs that we'd find them on. 274 00:17:14,783 --> 00:17:17,202 And I always wondered why would an animal 275 00:17:17,286 --> 00:17:21,165 that's so focused on camouflage then start glowing? 276 00:17:22,041 --> 00:17:24,793 NARRATOR: Ryan designed a specialized camera 277 00:17:24,877 --> 00:17:29,048 outfitted with UV lights to observe glowing puffadders. 278 00:17:29,840 --> 00:17:31,425 RYAN: Ready, buddy? 279 00:17:32,259 --> 00:17:38,057 NARRATOR: Documenting them firsthand will require diving this shark-filled bay... 280 00:17:39,016 --> 00:17:40,142 at night. 281 00:17:43,896 --> 00:17:45,939 RYAN: Night diving is an acquired taste. 282 00:17:46,023 --> 00:17:49,860 And tonight, all we're gonna have is this UV light, 283 00:17:49,943 --> 00:17:53,572 which is essentially invisible to us. The rest of it's gonna be black. 284 00:17:54,448 --> 00:17:57,409 NARRATOR: In the deep, dark oceans around the world, 285 00:17:57,493 --> 00:18:03,248 some species of marine life have evolved not to camouflage, but to glow. 286 00:18:04,541 --> 00:18:09,546 These abilities are called bioluminescence and biofluorescence. 287 00:18:09,630 --> 00:18:14,927 Bioluminescence is a chemical process in which an organism generates light. 288 00:18:15,636 --> 00:18:18,806 Like a lantern shark that glows to avoid predators, 289 00:18:19,473 --> 00:18:22,476 or plankton glowing at the ocean's surface. 290 00:18:23,102 --> 00:18:29,650 Biofluorescence... is a different and more mysterious process. 291 00:18:31,318 --> 00:18:33,737 GIBBS: Biofluorescence is the ability for an organism 292 00:18:33,821 --> 00:18:38,200 to take in a certain wavelength of light and re-emit a different wavelength. 293 00:18:38,283 --> 00:18:41,829 RYAN: As you go deeper, all the light disappears except for blue light. 294 00:18:41,912 --> 00:18:43,497 And what these puffadders seem to do 295 00:18:43,580 --> 00:18:47,876 is take in that blue light, then emit out this yellow-green light 296 00:18:47,960 --> 00:18:50,546 that sort of gives them this glow-in-the-dark appearance. 297 00:18:51,046 --> 00:18:53,924 GIBBS: The key here is to figure out how sharks are using light 298 00:18:54,007 --> 00:18:56,969 and color to be better adapted to their environment. 299 00:18:57,052 --> 00:19:01,265 So we're here to explore what this does for them and their survival. 300 00:19:01,348 --> 00:19:05,227 NARRATOR: Many corals, over 180 species of fish, 301 00:19:06,019 --> 00:19:11,817 and even some crabs display neon colors when exposed to UV light. 302 00:19:13,110 --> 00:19:16,321 Swell sharks in California also glow green 303 00:19:16,405 --> 00:19:19,449 under light that mimics how they see one another. 304 00:19:21,201 --> 00:19:25,414 Why is not exactly known, but many scientists believe 305 00:19:25,497 --> 00:19:28,208 it comes down to enabling communication 306 00:19:28,292 --> 00:19:31,295 while still retaining camouflage from predators. 307 00:19:32,629 --> 00:19:34,798 RYAN: And what we think is happening is that 308 00:19:34,882 --> 00:19:38,468 the shark's eyes evolved to see this yellow-green 309 00:19:38,552 --> 00:19:40,179 sort of spectrum of the light. 310 00:19:41,430 --> 00:19:43,390 GIBBS: This is an adaptation so they can essentially, 311 00:19:43,473 --> 00:19:47,060 at night, navigate these waters undetected 312 00:19:47,144 --> 00:19:49,855 from other organisms but still be able to see each other. 313 00:19:50,689 --> 00:19:52,774 NARRATOR: Even as they glow to one another, 314 00:19:52,858 --> 00:19:58,697 camouflage remains key to their survival, as it may be for the great white. 315 00:19:58,780 --> 00:20:01,867 Biology is inherently a comparative art. 316 00:20:01,950 --> 00:20:07,080 We understand more about one species by understanding how other species do it. 317 00:20:08,207 --> 00:20:11,418 NARRATOR: Whether camouflaging or communicating, 318 00:20:12,794 --> 00:20:17,007 the puffadder's appearance seems to be connected to its behavior. 319 00:20:20,802 --> 00:20:22,429 RYAN: So there's two parts of the color theory. 320 00:20:22,512 --> 00:20:26,308 One is that individual sharks can manipulate their color 321 00:20:26,391 --> 00:20:31,939 and two, that their color is determined by different activities. 322 00:20:32,022 --> 00:20:34,024 NARRATOR: With the color board repaired, 323 00:20:35,525 --> 00:20:38,779 the team sets out in search of more great whites 324 00:20:38,862 --> 00:20:40,948 to document for their database. 325 00:20:41,657 --> 00:20:44,451 I know this is a resting area for great white sharks. 326 00:20:45,077 --> 00:20:48,288 So the idea is to try to get this color board 327 00:20:48,372 --> 00:20:52,125 next to what I think is a resting shark. 328 00:20:55,462 --> 00:20:59,466 And if it is that this color is controlled by the hormone levels, 329 00:20:59,549 --> 00:21:04,054 you could find that a resting shark hanging out is a very different color 330 00:21:04,137 --> 00:21:06,848 to one that's motivated by hunting or scavenging. 331 00:21:12,854 --> 00:21:18,568 NARRATOR: While Ryan operates a drone, Gibbs captains a remote-controlled boat. 332 00:21:18,652 --> 00:21:19,528 (propeller whirring) 333 00:21:22,781 --> 00:21:24,658 RYAN: Hey, I got a shark. Gibbs, I got a shark, buddy! 334 00:21:24,741 --> 00:21:26,576 -GIBBS: You got one? -RYAN: I'm on a shark. (laughs) 335 00:21:26,660 --> 00:21:29,579 GIBBS: Alright. Let's throw this RC boat in. 336 00:21:31,164 --> 00:21:32,582 Okay, let go, let go. 337 00:21:33,208 --> 00:21:34,668 -You got it. -RYAN: Go, you got to go hard, buddy. 338 00:21:34,751 --> 00:21:36,545 Go hard, go fast. 339 00:21:39,006 --> 00:21:42,384 -Can you see me? -RYAN: Not yet. Not yet. 340 00:21:42,467 --> 00:21:44,886 GIBBS: Uh, going forward still. 341 00:21:45,387 --> 00:21:46,805 -RYAN: Gotcha. -GIBBS: Yeah, I think that's it. 342 00:21:46,888 --> 00:21:49,182 RYAN: I gotcha, buddy. You got it? 343 00:21:50,392 --> 00:21:52,185 -(laughs) -Nice. 344 00:21:52,936 --> 00:21:54,855 -RYAN: I'm just gonna bring it around. -GIBBS: Yeah. 345 00:21:55,272 --> 00:21:56,189 You got me there? 346 00:21:56,273 --> 00:21:59,318 RYAN: Yeah, I'm gonna bring it down lower, just so I can get the color... 347 00:21:59,735 --> 00:22:00,819 There we go. So we get the color board. 348 00:22:00,902 --> 00:22:03,030 -GIBBS: Nice. -RYAN: Okay, that's good. 349 00:22:03,113 --> 00:22:04,656 There she is, she's up at the surface now. 350 00:22:04,740 --> 00:22:06,199 -Yeah. Outstanding. -Yeah, man. 351 00:22:06,783 --> 00:22:10,662 NARRATOR: A resting shark and color board are in shot. 352 00:22:10,746 --> 00:22:15,125 It could provide very different data to the great white mid-hunt. 353 00:22:15,208 --> 00:22:18,503 This is just one piece of a far larger experiment. 354 00:22:20,005 --> 00:22:23,133 NARRATOR: To contrast with images of resting at the surface 355 00:22:24,009 --> 00:22:29,973 and hunting above it, the team also needs to capture color data at depth 356 00:22:30,349 --> 00:22:32,184 when sharks are scavenging. 357 00:22:33,810 --> 00:22:37,564 RYAN: Color changes very quickly as you go deeper into the water column. 358 00:22:37,731 --> 00:22:41,651 The reason why I'm so interested in doing the experiments down deep 359 00:22:41,735 --> 00:22:44,529 is because how a shark would camouflage itself 360 00:22:44,613 --> 00:22:46,740 at the surface is very different 361 00:22:46,823 --> 00:22:48,700 to how it would camouflage itself at the bottom. 362 00:22:50,202 --> 00:22:55,248 NARRATOR: Ryan will be lowered over 30 feet in his custom dive cage. 363 00:22:56,375 --> 00:22:57,959 Come on out, and let's get this cage down there. 364 00:23:03,715 --> 00:23:06,760 We lost the GoPro zoom. It's gonna be in the cage. 365 00:23:09,721 --> 00:23:14,309 Oh, she's gonna go right for the cage. Nice. 366 00:23:15,435 --> 00:23:18,563 The purpose of this whole, you know, attracting sharks to the boat 367 00:23:18,647 --> 00:23:20,690 was to get them close to the color board. 368 00:23:24,194 --> 00:23:28,115 Another shark. Drew, look at her diving down there. 369 00:23:28,198 --> 00:23:30,242 RYAN: When you are down deep there, 370 00:23:30,325 --> 00:23:32,744 you don't know if what you're seeing is actually accurate 371 00:23:32,828 --> 00:23:37,874 because the light has degraded so much, and the visibility is so bad. 372 00:23:37,958 --> 00:23:41,002 So that's why it's really essential that we have that color board, 373 00:23:41,086 --> 00:23:44,297 and we can capture the shark and the color board together. 374 00:23:44,381 --> 00:23:46,299 'Cause then I can take it back, correct it, 375 00:23:46,383 --> 00:23:49,553 and work out truthfully what the color of that shark is. 376 00:23:55,559 --> 00:23:59,354 Now she dives down. These sharks are giving us plenty of data. 377 00:24:13,702 --> 00:24:17,706 NARRATOR: It's a rare glimpse into the great white's deep-water world, 378 00:24:18,874 --> 00:24:21,960 where they scavenge for rays and other prey. 379 00:24:22,043 --> 00:24:27,257 RYAN: The whole setup worked well. What was striking me was the camouflage. 380 00:24:28,133 --> 00:24:31,303 It is the camouflage that makes these sharks successful. 381 00:24:31,386 --> 00:24:34,097 That ability to blend into the environment, 382 00:24:34,181 --> 00:24:37,934 and that environment down there, it's, it's monochrome. 383 00:24:38,477 --> 00:24:41,188 -Hey, you work for it. You work for it. -Yeah, sure. 384 00:24:42,355 --> 00:24:47,319 NARRATOR: With their database nearly complete, Ryan and Gibbs are finally able 385 00:24:47,402 --> 00:24:52,574 to turn their research further afield to reports from a remote part of the world 386 00:24:53,366 --> 00:24:57,496 and another unique shark skin adaptation. 387 00:25:01,666 --> 00:25:04,669 GIBBS: As part of our investigation on sharks and color, 388 00:25:05,212 --> 00:25:07,255 we're looking for another species of shark 389 00:25:07,339 --> 00:25:11,551 that may actually be able to change their color for the sake of camouflage. 390 00:25:14,095 --> 00:25:17,974 NARRATOR: Species like the wobbegong and angel shark 391 00:25:18,350 --> 00:25:22,854 use unique skin patterns evolved over millions of years 392 00:25:22,938 --> 00:25:25,482 to camouflage into their surroundings. 393 00:25:27,317 --> 00:25:30,946 But sharks with changing skin patterns are rare. 394 00:25:32,948 --> 00:25:35,742 A study in the Maldives investigates 395 00:25:35,825 --> 00:25:39,246 whether a genetic condition is causing one species 396 00:25:39,329 --> 00:25:41,873 to exhibit this uncommon adaptation. 397 00:25:41,957 --> 00:25:44,334 GIBBS: We are here in the beautiful, sunny Maldives 398 00:25:44,417 --> 00:25:46,169 in a place called Baa Atoll 399 00:25:46,253 --> 00:25:49,631 looking for a very rare type of blacktip reef shark. 400 00:25:50,382 --> 00:25:54,553 NARRATOR: Tropical reefs are hot spots of life and adaptation. 401 00:25:55,011 --> 00:26:00,850 While some creatures try to stand out, others do all they can to blend in. 402 00:26:01,393 --> 00:26:06,856 Could this unique case provide clues to how great white skin might change? 403 00:26:06,940 --> 00:26:10,902 My perspective on what brings great whites close 404 00:26:10,986 --> 00:26:14,364 to these blacktip reef sharks is down at the molecular level. 405 00:26:14,447 --> 00:26:19,744 This report came out a couple years ago, and it had these images of these sharks 406 00:26:19,828 --> 00:26:22,247 that had developed this weird spotted pattern. 407 00:26:22,330 --> 00:26:26,876 And I think this might be caused by a genetic disorder called leucism. 408 00:26:27,377 --> 00:26:32,799 Leucism is a genetic trait that's caused by the malfunction of the melanocytes. 409 00:26:33,341 --> 00:26:39,055 So when it stops working properly, we start to see this patchy distribution 410 00:26:39,139 --> 00:26:42,183 where melanin pigment in the shark is lost. 411 00:26:45,478 --> 00:26:49,524 NARRATOR: Gibbs is using methods both old and new... 412 00:26:50,859 --> 00:26:55,655 seeking photographic evidence and genetic samples of leucistic sharks. 413 00:26:57,782 --> 00:27:03,913 But is this condition an unfortunate aberration or possibly rapid adaptation? 414 00:27:03,997 --> 00:27:07,334 This genetic disorder of leucism is like a freak accident. 415 00:27:09,628 --> 00:27:12,505 It might have the exact key these sharks need 416 00:27:12,589 --> 00:27:15,008 to be camouflaged better in their environment. 417 00:27:16,676 --> 00:27:20,764 If these blacktip reef sharks are actually able to camouflage, 418 00:27:20,847 --> 00:27:23,850 it really means that these sharks have somehow or another 419 00:27:23,933 --> 00:27:29,230 found a way to actually live around the human impacts of climate change. 420 00:27:30,190 --> 00:27:32,942 And I say this because the Maldives has actually experienced 421 00:27:33,026 --> 00:27:35,612 quite a bit of negative impacts from climate change. 422 00:27:36,071 --> 00:27:39,199 Sea surface temperatures have been above 30 degrees, 423 00:27:39,282 --> 00:27:43,161 and that's caused the corals to bleach. So when you see the coral reef, 424 00:27:43,244 --> 00:27:46,956 there's a whole bunch of dead corals mixed in with the living corals, 425 00:27:47,040 --> 00:27:50,794 and that makes the environment have this random scattered pattern. 426 00:27:50,877 --> 00:27:54,172 And I think these sharks might actually be blending in better 427 00:27:54,255 --> 00:27:56,508 in their environment than the other sharks 428 00:27:56,591 --> 00:27:58,718 that haven't developed this genetic disorder. 429 00:28:01,012 --> 00:28:03,431 From the report, we found that these sharks 430 00:28:03,515 --> 00:28:05,934 that have the leucism are all juveniles, 431 00:28:06,017 --> 00:28:10,397 which makes me think that either these sharks are surviving 432 00:28:10,480 --> 00:28:16,027 and growing out of this skin pattern, or maybe this genetic disorder is lethal. 433 00:28:16,111 --> 00:28:20,782 But all we would need is proof of just one subadult animal 434 00:28:20,865 --> 00:28:24,536 with this trait to say that actually there is a chance that they are surviving. 435 00:28:28,373 --> 00:28:31,584 The Maldives is a perfect place to find these blacktip reef sharks. 436 00:28:32,377 --> 00:28:34,879 Unfortunately, they are very skittish. 437 00:28:45,724 --> 00:28:48,309 -Hey, Ryan, how's it going? -RYAN (over video): I'm doing well, man. 438 00:28:48,393 --> 00:28:51,146 I'm curious, very curious how it's going in Maldives. 439 00:28:51,229 --> 00:28:53,231 Have you managed to be able to catch the sharks, 440 00:28:53,314 --> 00:28:55,650 do the genetic samples, anything like that yet? 441 00:28:55,734 --> 00:28:57,944 I haven't been able to get my hands on these sharks. 442 00:28:58,027 --> 00:29:02,699 Unfortunately, it's, it's a bit more challenging than I expected. 443 00:29:02,782 --> 00:29:08,037 But we did manage to get one leucistic blacktip reef shark in plain view. 444 00:29:08,121 --> 00:29:09,497 So that's, that's something. 445 00:29:09,581 --> 00:29:11,166 Do they actually blend in? 446 00:29:11,249 --> 00:29:15,086 GIBBS: I would definitely say that their random pattern is matching 447 00:29:15,170 --> 00:29:20,467 that random pattern of the coral reefs. And unlike the smaller ones, 448 00:29:20,550 --> 00:29:24,304 leucism is actually presenting itself a little bit less. 449 00:29:24,387 --> 00:29:27,223 It's almost like these larger ones are growing out of it. 450 00:29:27,557 --> 00:29:30,560 RYAN: Wow. The zebra shark does exactly that: 451 00:29:30,643 --> 00:29:33,688 as they grow up, then they change their color. 452 00:29:33,772 --> 00:29:35,106 NARRATOR: Like the zebra shark, 453 00:29:35,523 --> 00:29:38,735 this group of blacktips could be morphing their skin pattern 454 00:29:38,818 --> 00:29:41,696 as they grow and become less vulnerable. 455 00:29:41,780 --> 00:29:43,740 And while any heightened camouflage 456 00:29:43,823 --> 00:29:46,618 seems to be connected to melanocytes in the skin, 457 00:29:47,160 --> 00:29:51,331 leucism appears very different to any rapid hormonal change 458 00:29:51,414 --> 00:29:54,042 affecting the skin of great whites. 459 00:29:54,125 --> 00:29:56,461 Whilst we are seeing some color aberrations, 460 00:29:56,544 --> 00:30:00,548 I don't think this is exactly what I was looking for when I came out here. 461 00:30:00,632 --> 00:30:02,675 RYAN: Now, I've been thinking more about the great white 462 00:30:02,759 --> 00:30:05,178 and the skin sample test and the hormone test. 463 00:30:05,261 --> 00:30:06,596 We didn't get the response. 464 00:30:06,679 --> 00:30:09,641 I want to know more about this and whether we got a solution. 465 00:30:09,724 --> 00:30:12,435 Clearly, the dead cells didn't work. 466 00:30:12,519 --> 00:30:15,939 So I would suggest that we get back out there 467 00:30:16,022 --> 00:30:19,234 and collect some of this live tissue from the great whites 468 00:30:19,317 --> 00:30:22,487 so that we can actually get these cells to change in real time. 469 00:30:23,655 --> 00:30:27,909 NARRATOR: While the team prepares for a final attempt to collect live samples, 470 00:30:28,159 --> 00:30:30,036 Ryan begins to crunch the numbers 471 00:30:30,119 --> 00:30:33,331 on his color board database for the first time. 472 00:30:34,290 --> 00:30:37,710 We've put the color board alongside the cage diving boat 473 00:30:37,794 --> 00:30:41,089 where we can see a shark that's in a scavenging mode. 474 00:30:41,172 --> 00:30:45,760 We've also taken the color board down to the bottom of the ocean. 475 00:30:46,469 --> 00:30:48,596 And then we've also looked for resting sharks. 476 00:30:49,097 --> 00:30:51,724 The most exciting experiment, but the most challenging, 477 00:30:51,808 --> 00:30:56,354 was getting the color board next to breaching, hunting great white sharks. 478 00:30:56,437 --> 00:30:58,106 In this type of behavior mode, 479 00:30:58,189 --> 00:31:00,942 these sharks need to maximize their camouflage. 480 00:31:03,862 --> 00:31:06,781 If we can match up the sharks in different experiments, 481 00:31:06,865 --> 00:31:12,203 we can see whether those sharks, in fact, do change color, and then secondly, 482 00:31:12,787 --> 00:31:16,457 how that color relates to the different activities. 483 00:31:16,541 --> 00:31:20,587 NARRATOR: The first step is to identify images of an individual shark 484 00:31:20,670 --> 00:31:23,506 that were captured in various experiments. 485 00:31:23,590 --> 00:31:27,886 RYAN: The idea is that we sort of build up the identification of the shark 486 00:31:27,969 --> 00:31:31,222 over different images, over different situations. 487 00:31:31,306 --> 00:31:35,226 And now I've got one shark, this shark with a very distinct abscess 488 00:31:35,643 --> 00:31:39,230 on a jaw that we've been able to see in multiple locations. 489 00:31:40,732 --> 00:31:42,400 NARRATOR: Ryan carefully adjusts the images 490 00:31:42,859 --> 00:31:46,487 so the grayscale color boards are matching in every shot. 491 00:31:46,571 --> 00:31:49,949 RYAN: The goal is adjust the square here to get true white. 492 00:31:50,033 --> 00:31:52,577 We can adjust this square here to get true black. 493 00:31:52,660 --> 00:31:55,747 Once we've done that, we know that every pixel in that frame 494 00:31:55,830 --> 00:31:57,081 is exactly correct. 495 00:31:57,165 --> 00:31:58,249 NARRATOR: Once calibrated, 496 00:31:58,333 --> 00:32:01,169 Ryan can then isolate and analyze 497 00:32:01,252 --> 00:32:04,088 the color of the shark in different states of activity, 498 00:32:04,172 --> 00:32:07,342 assigning their skin shade a numeric value. 499 00:32:07,425 --> 00:32:13,306 RYAN: One being very dark, almost black, 100 being very white, almost pure white. 500 00:32:13,806 --> 00:32:17,769 We can't always get the entire shark's body into frame, 501 00:32:17,852 --> 00:32:21,147 but we can work with certain parts of the shark's body. 502 00:32:26,611 --> 00:32:27,820 So we've got it here. 503 00:32:27,904 --> 00:32:31,532 We've got the breaching, hunting shark scoring a score of around 22, 504 00:32:31,616 --> 00:32:33,451 which is a very dark color 505 00:32:33,534 --> 00:32:37,330 versus here, the same shark is around the boat, 506 00:32:37,413 --> 00:32:40,208 and it's scoring around 54, 53. 507 00:32:40,291 --> 00:32:42,669 So, clearly, light coloration, dark coloration. 508 00:32:42,752 --> 00:32:47,006 Is it at the stage where we can make big conclusions? No. 509 00:32:47,090 --> 00:32:51,010 But what it has proven is that this individual shark 510 00:32:51,094 --> 00:32:52,845 has the ability to change color. 511 00:32:52,929 --> 00:32:55,890 And over time, we're gonna be able to build up this database 512 00:32:55,974 --> 00:32:59,602 and work out how individual sharks can change their color 513 00:32:59,686 --> 00:33:02,814 and whether the color that they adopt at any given time 514 00:33:02,897 --> 00:33:05,942 is related to what activity they are involved with. 515 00:33:06,025 --> 00:33:09,988 NARRATOR: It's a satisfying result after months of field work. 516 00:33:10,071 --> 00:33:13,324 But the next stage of the investigation will be crucial 517 00:33:13,408 --> 00:33:17,286 to proving that great whites really are camo sharks. 518 00:33:17,912 --> 00:33:20,373 RYAN: Second, we're gonna switch to the molecular level. 519 00:33:20,456 --> 00:33:23,167 And that is getting live samples from the great whites, 520 00:33:23,251 --> 00:33:27,171 getting them down to the laboratory and analyzing them under the microscope. 521 00:33:27,255 --> 00:33:29,549 We're gonna be able to answer once and for all 522 00:33:29,632 --> 00:33:32,927 whether these great whites can, in fact, change their color. 523 00:33:35,013 --> 00:33:37,682 (birds squawking) 524 00:33:38,224 --> 00:33:40,977 NARRATOR: Gibbs and Ryan have an ambitious plan 525 00:33:41,060 --> 00:33:43,604 for one final molecular test. 526 00:33:43,688 --> 00:33:46,024 The behavior is only one side of the study. 527 00:33:46,107 --> 00:33:50,111 The cellular work is the other side, and it's equally as important. 528 00:33:50,778 --> 00:33:56,117 NARRATOR: But this time, they'll need a skin sample from a live great white shark. 529 00:33:57,201 --> 00:33:59,829 GIBBS: The reason we go out to collect fresh tissue samples 530 00:33:59,912 --> 00:34:01,831 is because the shark skin is still alive, 531 00:34:01,914 --> 00:34:06,127 and thus, theoretically, it should respond to the hormonal treatments we give it. 532 00:34:06,210 --> 00:34:09,839 That's why we're taking these extra steps, so we can make sure the experiment works. 533 00:34:11,007 --> 00:34:12,675 We are bringing the lab into the field. 534 00:34:13,384 --> 00:34:16,763 I've got my sampling probes which I'll attach to the dart gun. 535 00:34:16,846 --> 00:34:21,059 You can see I've got three solutions that give that life-giving fluid 536 00:34:21,142 --> 00:34:24,103 so the tissue stays alive long enough for us to get to the lab. 537 00:34:26,147 --> 00:34:29,859 If we can get live tissue to the lab, apply the hormones, 538 00:34:29,942 --> 00:34:33,863 and witness under the microscope the pigment dispersing and aggregating, 539 00:34:33,946 --> 00:34:37,575 we're getting somewhere. If it dies, it's all wasted. 540 00:34:38,076 --> 00:34:40,119 NARRATOR: A successful experiment 541 00:34:40,203 --> 00:34:44,332 could provide definitive evidence for their color change theory. 542 00:34:46,334 --> 00:34:49,295 But first, they need a sample. 543 00:34:49,378 --> 00:34:52,006 GIBBS: To be in the cage at the shark's level 544 00:34:52,090 --> 00:34:55,176 is probably the best vantage point we're going to get to sample them. 545 00:34:55,259 --> 00:34:57,470 I would lie if I said I wasn't a little bit nervous. 546 00:34:57,553 --> 00:35:00,973 There is an element of danger with dealing with these animals. 547 00:35:03,559 --> 00:35:06,604 RYAN: I'm gonna try to get the bait down past you. 548 00:35:06,687 --> 00:35:07,563 GIBBS: Mm-hmm. 549 00:35:07,647 --> 00:35:09,607 RYAN: And then I'm gonna try to get the shark to follow 550 00:35:09,690 --> 00:35:12,985 and come close to you as possible. And that's when you want to go for it. 551 00:35:13,069 --> 00:35:15,279 -We got this. -We got this. 552 00:35:21,244 --> 00:35:24,080 I think that's-- Oh, bait! Oh! 553 00:35:24,163 --> 00:35:26,624 That's gone, that's gone, that's gone, that's gone, that's gone. 554 00:35:26,707 --> 00:35:29,043 Come on, Gibbsy, the sharks are working, buddy! 555 00:35:29,627 --> 00:35:32,046 GIBBS: The margin of error is quite small. 556 00:35:32,130 --> 00:35:35,508 So I can sample them in the right spot, so that I can get the right tissue 557 00:35:35,591 --> 00:35:38,719 -and also not harm the sharks. -RYAN: Here he comes. 558 00:35:40,847 --> 00:35:41,806 Woo! 559 00:35:43,850 --> 00:35:45,351 -They're fast! -Yeah. 560 00:35:45,434 --> 00:35:46,561 Dang! 561 00:36:09,834 --> 00:36:10,751 MAN: Good eyes. 562 00:36:11,252 --> 00:36:13,296 (camera shutter clicking) RYAN: No, no, no. 563 00:36:14,839 --> 00:36:16,340 He speared it! He speared it! 564 00:36:18,217 --> 00:36:20,678 Nice! It was actually a good placement. 565 00:36:22,722 --> 00:36:24,056 Nice work, Gibbs! 566 00:36:24,765 --> 00:36:27,894 Perfect. Woo! How did that look? 567 00:36:27,977 --> 00:36:29,353 GIBBS: It worked out perfectly. 568 00:36:30,813 --> 00:36:34,734 RYAN: Nice, man. (laughs) Okay, let me process this. 569 00:36:34,817 --> 00:36:38,070 That's the key part we're looking for, the skin. 570 00:36:38,696 --> 00:36:40,698 NARRATOR: With the first sample on deck, 571 00:36:40,781 --> 00:36:44,076 they only have an hour to collect the remaining samples. 572 00:36:44,577 --> 00:36:46,537 We have to make sure that tissue stays alive 573 00:36:46,621 --> 00:36:49,415 -long enough for us to get to the lab. -Look at that. 574 00:36:50,833 --> 00:36:52,293 -Aggressing a lot. -MAN: Here comes the shark again. 575 00:36:52,835 --> 00:36:54,170 And grayer in color. 576 00:36:54,253 --> 00:36:55,630 -Did you see that? -Yeah. Yeah. I did see that. 577 00:36:58,507 --> 00:37:00,134 RYAN: Got it! Got it! Yeah! 578 00:37:01,093 --> 00:37:02,345 NARRATOR: Two down. 579 00:37:03,262 --> 00:37:06,599 RYAN: Perfect shot. My boy has got it. Gibbs is shooting well. 580 00:37:07,183 --> 00:37:08,517 That's where the tissue is thickest. 581 00:37:08,601 --> 00:37:10,895 You're gonna stay far away from any of the vital organs 582 00:37:10,978 --> 00:37:13,439 if you hit just at the base of the dorsal fin like that. 583 00:37:13,522 --> 00:37:15,107 Perfect little skin tag. 584 00:37:17,693 --> 00:37:18,861 -Got it. -MAN: Got it. 585 00:37:18,945 --> 00:37:21,072 RYAN: You know, I know that, I know he's been stressing a lot 586 00:37:21,155 --> 00:37:23,824 about his aim with that, so to actually see it placed 587 00:37:23,908 --> 00:37:26,244 so beautifully just at the base of the dorsal fin... 588 00:37:26,535 --> 00:37:28,663 -It's perfect. -It makes me really happy for him. 589 00:37:31,165 --> 00:37:33,542 Sheesh. Out of the blue, eh? 590 00:37:34,418 --> 00:37:36,545 It is a new shark. Yup. 591 00:37:36,629 --> 00:37:39,298 He was so shy just now, man. Just suddenly... 592 00:37:40,174 --> 00:37:43,386 Torpedo. Shows you what these things got in them when they want to get. 593 00:37:43,469 --> 00:37:45,388 Oh, there he is again. Bring the one that we have. 594 00:37:45,471 --> 00:37:47,682 We have to look on this side of her, this side of her. 595 00:37:47,765 --> 00:37:49,934 See if that-- 'cause he did hit one low. 596 00:37:50,017 --> 00:37:52,478 Problem is if we sampled the same shark twice. 597 00:37:52,561 --> 00:37:55,648 No, no. No, no, no, no, no, no. 598 00:37:56,232 --> 00:37:57,483 Look at that dorsal fin, it's very distinct. 599 00:37:57,566 --> 00:37:58,484 This guy is a player. 600 00:37:58,901 --> 00:38:00,528 -MAN: I think I got it. -It's got that hurt dorsal fin. 601 00:38:05,908 --> 00:38:07,201 Come on, Gibbs, hit the shot, hit the shot. 602 00:38:12,915 --> 00:38:15,251 This could be it, this could be our third successful sample, 603 00:38:15,334 --> 00:38:17,962 as long as Gibbs knows it's one that we can sample. 604 00:38:21,090 --> 00:38:22,300 Here he comes. Here he comes. 605 00:38:27,138 --> 00:38:28,055 -This could be it. -MAN: Turning, turning. 606 00:38:28,139 --> 00:38:30,474 RYAN: This could be it. This could be it. I'm just gonna bring him straight in. 607 00:38:31,684 --> 00:38:32,643 -Oh. -MAN: Oh. 608 00:38:32,727 --> 00:38:33,894 RYAN: Oh, geez! 609 00:38:42,528 --> 00:38:45,531 RYAN: No, come on, Gibbs! You've got this. You got this, buddy. 610 00:38:45,614 --> 00:38:48,367 NARRATOR: Ryan and Gibbs are running out of time. 611 00:38:48,451 --> 00:38:51,037 I think he's a bit shaken from when the shark hit the cage. 612 00:38:52,246 --> 00:38:54,707 Gibbs has had two perfect shots here, but he's not firing. 613 00:38:55,207 --> 00:38:58,669 NARRATOR: Shark's skin begins to die the minute it's sampled. 614 00:38:59,545 --> 00:39:01,881 They need the final skin tag now 615 00:39:01,964 --> 00:39:05,009 if they're going to make it to Cape Town with living tissue. 616 00:39:07,219 --> 00:39:08,512 MAN: Yeah, right in front of him. 617 00:39:12,475 --> 00:39:15,978 -Yeah, he got it. -RYAN: Oh, he got it. Bang on, bang on. 618 00:39:17,521 --> 00:39:19,940 (laughs) Nice. 619 00:39:20,649 --> 00:39:23,486 Yeah, that was pretty good. This should give us some really good data. 620 00:39:26,530 --> 00:39:29,283 Woo! It's on you, man. Well done! 621 00:39:29,742 --> 00:39:32,495 -Thanks. Alright. Let's get out. -RYAN: Get changed, we're pulling anchor. 622 00:39:33,412 --> 00:39:37,124 RYAN: So we've got about four hours, five hours max to get to Cape Town. 623 00:39:38,667 --> 00:39:40,378 So let's move, come on! 624 00:39:42,421 --> 00:39:46,175 NARRATOR: Ryan and Gibbs rush the samples to a lab in Cape Town. 625 00:39:47,718 --> 00:39:50,763 They're seeking the expertise of cellular biologist 626 00:39:50,846 --> 00:39:53,974 and imaging specialist Dr. Dirk Lang. 627 00:39:54,558 --> 00:39:58,229 DR. DIRK LANG: I mean, you guys must have had an incredibly full schedule today. 628 00:39:58,312 --> 00:40:01,732 RYAN: Well, we realized when we got out there, we had about two hours to collect, 629 00:40:01,816 --> 00:40:03,317 and I wanted at least three samples for us. 630 00:40:03,401 --> 00:40:04,276 DR. LANG: Okay. 631 00:40:05,027 --> 00:40:10,950 RYAN: If we can prove that great white shark skin is controlled by hormones, 632 00:40:11,033 --> 00:40:15,121 that's over half of our whole mission answered right then and there. 633 00:40:15,913 --> 00:40:18,457 NARRATOR: While Gibbs prepares hormonal solutions, 634 00:40:19,083 --> 00:40:23,671 Dirk prepares the shark skin samples to ensure they stay alive during testing. 635 00:40:24,422 --> 00:40:26,340 -Hey, guys. -How's it going, Gibbs? 636 00:40:26,424 --> 00:40:29,218 GIBBS: You know, it's my first time going straight from the sea to the lab. 637 00:40:29,301 --> 00:40:30,219 This isn't right for me. 638 00:40:31,387 --> 00:40:34,557 NARRATOR: The shark skin reactions to these hormonal tests 639 00:40:35,182 --> 00:40:38,227 will be documented using a confocal microscope. 640 00:40:38,936 --> 00:40:41,439 RYAN: If we can see microscopically 641 00:40:41,856 --> 00:40:45,568 these pigment cells aggregating and dispersing, 642 00:40:45,651 --> 00:40:48,612 there'll be no doubt that there is color change in these sharks. 643 00:40:49,738 --> 00:40:52,116 NARRATOR: The powerful microscope will allow them 644 00:40:52,199 --> 00:40:55,202 to actually see melanocytes in the skin 645 00:40:55,286 --> 00:40:58,873 and determine whether they react to hormonal stimulus. 646 00:40:58,956 --> 00:41:01,709 GIBBS: So we're gonna see a time lapse, and that might actually help us figure out 647 00:41:01,792 --> 00:41:04,086 how this color change mechanism really works. 648 00:41:05,463 --> 00:41:09,467 NARRATOR: The first test is with the melanocyte-stimulating hormone. 649 00:41:10,134 --> 00:41:15,097 If their theory is correct, this should cause a dispersal of melanocytes 650 00:41:15,181 --> 00:41:16,765 and a darkening of the pigment. 651 00:41:17,433 --> 00:41:19,685 The second hormone is adrenaline, 652 00:41:20,186 --> 00:41:23,731 which they believe would be present during behavior like hunting. 653 00:41:26,817 --> 00:41:30,613 Third is melatonin, a hormone associated with resting. 654 00:41:31,197 --> 00:41:34,825 This could emulate a shark in a relaxed state. 655 00:41:35,284 --> 00:41:37,161 So this is, this is hormones that the sharks 656 00:41:37,244 --> 00:41:40,206 would be producing themselves in different environments. 657 00:41:40,289 --> 00:41:43,626 Now we're flushing the skin with it, trying to replicate the response. 658 00:41:44,793 --> 00:41:47,296 GIBBS: Most people think the most exciting part of my job 659 00:41:47,379 --> 00:41:49,757 is out in the field, but the excitement that I'm getting 660 00:41:49,840 --> 00:41:52,426 from the lab is, is on a different level. 661 00:41:52,510 --> 00:41:54,678 NARRATOR: As the time lapses come in, 662 00:41:54,762 --> 00:41:58,015 it's clear the hormones are affecting the skin samples. 663 00:42:00,935 --> 00:42:04,355 In the sample treated with the melanocyte-stimulating hormone, 664 00:42:05,231 --> 00:42:09,401 the melanocytes have dispersed, making the skin appear darker. 665 00:42:09,485 --> 00:42:12,488 This sample is on a living great white shark, not... 666 00:42:12,571 --> 00:42:14,365 -This morning. -...five hours ago. 667 00:42:14,448 --> 00:42:15,533 That is just so amazing. 668 00:42:16,283 --> 00:42:20,996 NARRATOR: Contrary to their prediction, the shark skin flushed with adrenaline 669 00:42:21,080 --> 00:42:25,292 shows the melanocyte cells contracting and appearing lighter. 670 00:42:25,376 --> 00:42:28,170 This would cause a paling effect. Huh. 671 00:42:28,254 --> 00:42:30,297 NARRATOR: Then there is the melatonin. 672 00:42:30,381 --> 00:42:33,342 GIBBS: We're seeing a mix of light and dark. 673 00:42:33,425 --> 00:42:36,095 RYAN: (laughs) And we're making history. 674 00:42:36,595 --> 00:42:39,640 We're seeing the changes, and you picture this in your head, 675 00:42:39,723 --> 00:42:41,600 that moment when you actually, 676 00:42:41,684 --> 00:42:45,729 wow, these cells are responding to the different hormones. 677 00:42:46,105 --> 00:42:50,442 It, it blows your mind. It's... it's incredible, it's awesome. 678 00:42:50,526 --> 00:42:54,655 -Color change in great white sharks. -GIBBS: This is exciting stuff. 679 00:42:54,738 --> 00:42:56,448 NARRATOR: Though the results are preliminary 680 00:42:57,157 --> 00:43:00,244 and more research is needed to understand the connection 681 00:43:00,327 --> 00:43:02,913 between shark hormones and behavior, 682 00:43:03,581 --> 00:43:08,836 the reaction of these microscopic melanocytes tells a very big story. 683 00:43:09,336 --> 00:43:12,506 RYAN: So what this means is that great whites can control their color 684 00:43:12,590 --> 00:43:15,009 and that the color that they choose to adopt 685 00:43:15,092 --> 00:43:18,637 is controlled by the hormones that they release into their blood system. 686 00:43:18,721 --> 00:43:21,599 I never thought I'd get moved in a scientific laboratory scene. 687 00:43:21,682 --> 00:43:24,602 You know, I'm used to seeing breaching sharks and all that excitement. 688 00:43:24,685 --> 00:43:26,645 But to come here to this sort of cellular level 689 00:43:26,729 --> 00:43:28,731 and see this incredible thing happening 690 00:43:28,814 --> 00:43:31,191 and knowing that this actually means something to science 691 00:43:31,275 --> 00:43:33,110 is, it's special, it is really special. 692 00:43:33,193 --> 00:43:35,154 NARRATOR: It's an incredible discovery 693 00:43:35,237 --> 00:43:39,241 that could totally change what we know about the great white. 694 00:43:39,325 --> 00:43:40,451 GIBBS: I really don't know what to say. 695 00:43:40,534 --> 00:43:43,579 I'm at a loss for words right now, because this is super cool. 696 00:43:43,662 --> 00:43:46,707 And I don't think I'm gonna have another moment like this 697 00:43:46,790 --> 00:43:48,667 in my science career for a long time. 698 00:43:49,501 --> 00:43:52,087 NARRATOR: With photographic and cellular evidence 699 00:43:52,171 --> 00:43:56,508 suggesting this species is capable of subtly changing its color, 700 00:43:57,760 --> 00:44:00,346 this is just the beginning of understanding 701 00:44:00,429 --> 00:44:04,224 the great white as a camo shark.