1 00:00:01,920 --> 00:00:06,360 Speaker 1: Welcome to brain Stuff, a production of iHeart Radio, Hey 2 00:00:06,400 --> 00:00:10,760 Speaker 1: brain Stuff, Lauren Bogle bomb here. Every so often, yellow 3 00:00:10,760 --> 00:00:14,520 Speaker 1: bellied sea snakes tie themselves in knots, but they, like 4 00:00:14,640 --> 00:00:18,400 Speaker 1: all servants, must regularly shed their skin. But the process 5 00:00:18,440 --> 00:00:21,319 Speaker 1: demands friction, and in the open sea it can be 6 00:00:21,400 --> 00:00:24,080 Speaker 1: hard to find a rock or reef to rub up against, 7 00:00:24,840 --> 00:00:29,720 Speaker 1: So the animals play contortionist twisting coils around coils, they 8 00:00:29,760 --> 00:00:33,559 Speaker 1: peel off old skin in an acrobatic looping maneuver. The 9 00:00:33,640 --> 00:00:37,480 Speaker 1: exercise has a nice side effect. Barnacles, oysters and other 10 00:00:37,600 --> 00:00:41,720 Speaker 1: tiny hitchhikers plague these snakes. To frequent sheds help keep 11 00:00:41,720 --> 00:00:45,880 Speaker 1: their numbers down. If you're an armless, legless air breather, 12 00:00:46,320 --> 00:00:49,600 Speaker 1: life in the ocean is fraught with challenges, yet the 13 00:00:49,680 --> 00:00:53,400 Speaker 1: fifty plus sea snake species alive today use all kinds 14 00:00:53,440 --> 00:00:57,440 Speaker 1: of amazing tricks to get by. A snake at sea 15 00:00:57,600 --> 00:01:01,600 Speaker 1: is not automatically a sea snake. Lots of unrelated species 16 00:01:01,640 --> 00:01:05,320 Speaker 1: frolic in our oceans from time to time. Reticulated pythons, 17 00:01:05,319 --> 00:01:08,160 Speaker 1: for example, will swim between islands along the coasts of 18 00:01:08,160 --> 00:01:11,839 Speaker 1: southeastern Asia, crossing distances that could wear out an Olympian 19 00:01:12,520 --> 00:01:17,600 Speaker 1: That doesn't, however, make them sea snakes. When naturalists talk 20 00:01:17,640 --> 00:01:21,400 Speaker 1: about sea snakes, they're usually referring to two very specific 21 00:01:21,440 --> 00:01:24,240 Speaker 1: groups of reptiles that are part of the Cobra family, 22 00:01:24,720 --> 00:01:29,120 Speaker 1: true sea snakes genus name Hydrophenia and sea krits or 23 00:01:29,240 --> 00:01:34,160 Speaker 1: lat cottona. We've already mentioned one of the former species, 24 00:01:34,680 --> 00:01:38,480 Speaker 1: yellow bellied sea snakes. Those oddball not tires are classic 25 00:01:38,600 --> 00:01:42,280 Speaker 1: hydro feads. True sea snakes like these have sworn off 26 00:01:42,319 --> 00:01:45,760 Speaker 1: of dry land altogether. Fully marine, they give birth to 27 00:01:45,840 --> 00:01:50,160 Speaker 1: live young at sea. Terrestrial births just aren't an option. 28 00:01:50,800 --> 00:01:54,200 Speaker 1: Hydro Feeds never ex the water voluntarily because they lack 29 00:01:54,280 --> 00:01:57,160 Speaker 1: the wide belly scales that other snakes used to crawl 30 00:01:57,320 --> 00:02:00,040 Speaker 1: over solid ground. Drop one on a beach in a 31 00:02:00,120 --> 00:02:02,680 Speaker 1: poor creature would struggle to move under its own power. 32 00:02:03,960 --> 00:02:06,920 Speaker 1: Sea krates are a bit less streamlined, but they're more 33 00:02:06,920 --> 00:02:10,480 Speaker 1: competent on land. They mate, shed and digest some of 34 00:02:10,520 --> 00:02:14,880 Speaker 1: their meals outside the water. Equipped with the requisite belly scales, 35 00:02:15,000 --> 00:02:17,680 Speaker 1: the animals are free to hit the turf, and like 36 00:02:17,800 --> 00:02:22,200 Speaker 1: sea turtles, they lay eggs in beachside nests. But the 37 00:02:22,240 --> 00:02:26,200 Speaker 1: similarities between these groups far outweigh their differences. All sea 38 00:02:26,280 --> 00:02:29,360 Speaker 1: krets and true sea snakes have paddle shaped tails that 39 00:02:29,440 --> 00:02:32,960 Speaker 1: help them zip through the water. They're also venomous, but 40 00:02:33,240 --> 00:02:36,840 Speaker 1: seldom kill human beings. The animals tend to be docile 41 00:02:36,880 --> 00:02:39,880 Speaker 1: around people, and bites usually only happen when a snake 42 00:02:39,919 --> 00:02:43,880 Speaker 1: feels trapped and stressed out. One banded sea kright fatally 43 00:02:43,919 --> 00:02:49,600 Speaker 1: bit a man after a fishing net ensnared it. Most 44 00:02:49,680 --> 00:02:52,120 Speaker 1: sea snakes inject their venom through hollow fangs at the 45 00:02:52,120 --> 00:02:54,880 Speaker 1: front of their mouth rather than waste its ammo. A 46 00:02:54,919 --> 00:02:58,680 Speaker 1: frightened sea snake will often administer dry bites striking its 47 00:02:58,720 --> 00:03:02,600 Speaker 1: foe without releasing pressure venom, but give them a wide 48 00:03:02,600 --> 00:03:06,040 Speaker 1: berth just to be safe. Neurotoxins in sea snake venoms 49 00:03:06,040 --> 00:03:10,520 Speaker 1: attack the victim's nervous system. Paralysis, spasms, and respiratory problems 50 00:03:10,600 --> 00:03:14,400 Speaker 1: may occur as the chemicals do their work. Fish are 51 00:03:14,400 --> 00:03:17,239 Speaker 1: the main food source for the vast majority of species. 52 00:03:17,800 --> 00:03:20,440 Speaker 1: Sometimes it pays to let dinner come to you. The 53 00:03:20,520 --> 00:03:23,680 Speaker 1: yellow bellied sea snake lies motionless at the ocean's surface, 54 00:03:23,960 --> 00:03:27,000 Speaker 1: waiting for careless fish to take refuge under its coils 55 00:03:27,080 --> 00:03:30,760 Speaker 1: before grabbing them. Other sea snakes drag fish out of 56 00:03:30,800 --> 00:03:34,120 Speaker 1: the cracks and crevices and coral reefs. Such hiding places 57 00:03:34,120 --> 00:03:38,360 Speaker 1: are frequented by eels, the banded seacrite's favorite prey, while 58 00:03:38,440 --> 00:03:41,800 Speaker 1: more rays can be dangerous. Game chrits immobilize them with 59 00:03:41,880 --> 00:03:46,360 Speaker 1: venom and then swallow the creatures whole. A few species, 60 00:03:46,400 --> 00:03:49,240 Speaker 1: like the spine tailed sea snake, eat only fish eggs. 61 00:03:49,960 --> 00:03:54,120 Speaker 1: These specialists have tiny fangs, and some have exceptionally weak venom. 62 00:03:54,680 --> 00:03:57,120 Speaker 1: Caviar can't swim away, so there's no need to give 63 00:03:57,160 --> 00:04:01,920 Speaker 1: it paralysis, but let a. Cattids and hydro feeds can't 64 00:04:02,000 --> 00:04:04,760 Speaker 1: drink sea water, so they need to keep hydrated by 65 00:04:04,800 --> 00:04:08,560 Speaker 1: other means. Sea krites have been observed licking fresh water 66 00:04:08,680 --> 00:04:11,440 Speaker 1: droplets off of plant leaves when they come ashore and 67 00:04:11,680 --> 00:04:15,440 Speaker 1: after storm. They sometimes gather on islands to drink from puddles. 68 00:04:16,680 --> 00:04:20,400 Speaker 1: When it rains over the ocean, an interesting phenomenon occurs. 69 00:04:20,720 --> 00:04:23,599 Speaker 1: New fallen drops congregate at the surface to form a 70 00:04:23,640 --> 00:04:28,520 Speaker 1: temporary and drinkable lens of fresh water. Yellow bellied sea 71 00:04:28,560 --> 00:04:32,440 Speaker 1: snakes use those lenses to quench their thirst, zeroing in 72 00:04:32,560 --> 00:04:37,400 Speaker 1: before the rainwater gets inundated with too much salt. Both 73 00:04:37,520 --> 00:04:40,960 Speaker 1: seacrites and true sea snakes have valves that can seal 74 00:04:41,000 --> 00:04:44,680 Speaker 1: off their nostrils and keep out water during dives. Some 75 00:04:44,720 --> 00:04:46,760 Speaker 1: species are known to stay underwater for three and a 76 00:04:46,760 --> 00:04:51,279 Speaker 1: half hours on end. None of these guys possess gills, though. 77 00:04:51,320 --> 00:04:55,119 Speaker 1: In twenty nineteen, researchers learned that the blue banded sea snake, 78 00:04:55,240 --> 00:04:58,680 Speaker 1: a true species, uses intricate blood vessels on its head 79 00:04:58,920 --> 00:05:01,920 Speaker 1: to pull oxygen straight out of the water. Not a 80 00:05:01,960 --> 00:05:06,880 Speaker 1: bad superpower. Sharks, crocodiles, and some birds of prey will 81 00:05:06,920 --> 00:05:10,760 Speaker 1: all eat sea snakes if given the chance to confuse attackers. 82 00:05:10,800 --> 00:05:14,360 Speaker 1: The yellow lipped seacrite has evolved deceptive markings that make 83 00:05:14,400 --> 00:05:16,839 Speaker 1: the end of its tail look like a second head. 84 00:05:18,400 --> 00:05:21,839 Speaker 1: Pollution is another big threat, especially to snakes who swim 85 00:05:21,920 --> 00:05:27,599 Speaker 1: and feed near industrial sites. Long before humans started contaminating things, 86 00:05:28,000 --> 00:05:31,400 Speaker 1: sea snakes had spread out across the Pacific and Indian Oceans. 87 00:05:31,920 --> 00:05:34,680 Speaker 1: Two landlocked lakes in the South Pacific have their own 88 00:05:34,680 --> 00:05:38,599 Speaker 1: resident species as well, just don't bother looking for them. 89 00:05:38,600 --> 00:05:42,479 Speaker 1: In the Atlantic, Earth's second biggest ocean, is free of 90 00:05:42,560 --> 00:05:47,000 Speaker 1: all sea snakes. Geography and climate may explain why the 91 00:05:47,080 --> 00:05:50,320 Speaker 1: scientists think that the reptiles ancestors evolved in the Western 92 00:05:50,400 --> 00:05:53,560 Speaker 1: Pacific six to eight million years ago. By the time 93 00:05:53,600 --> 00:05:57,040 Speaker 1: modern species reached the America's the Panama land Bridge between 94 00:05:57,040 --> 00:06:00,599 Speaker 1: North and South America might have already closed up and 95 00:06:00,920 --> 00:06:04,480 Speaker 1: cold water kills sea snakes so that have been unable 96 00:06:04,520 --> 00:06:09,360 Speaker 1: to swim around South America's Cape Horn. Meanwhile, Africa's southeastern 97 00:06:09,400 --> 00:06:13,000 Speaker 1: coast gets very little rainfall. Any sea snake foolish enough 98 00:06:13,080 --> 00:06:15,200 Speaker 1: to hang out there would have had a difficult time 99 00:06:15,279 --> 00:06:25,599 Speaker 1: staying hydrated. Even survivalists do have their limitations. Today's episode 100 00:06:25,640 --> 00:06:28,280 Speaker 1: was written by Mark Mancini and produced by Tyler Clay. 101 00:06:28,279 --> 00:06:30,520 Speaker 1: For more on this lots of other curious topics, visit 102 00:06:30,560 --> 00:06:33,080 Speaker 1: how stuff works dot com. Brain Stuff is a production 103 00:06:33,080 --> 00:06:35,560 Speaker 1: of iHeart Radio. For more podcasts in my heart Radio, 104 00:06:35,760 --> 00:06:38,479 Speaker 1: visit the iHeart Radio app, Apple Podcasts, or wherever you 105 00:06:38,520 --> 00:06:39,760 Speaker 1: listen to your favorite shows.