Summary
Come learn about the heads of hammerhead sharks and find out why a fish would hold their breath underwater.
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Transcript
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| 0:00.0 | Why would a fish hold their breath underwater? I remember growing up back when I was boxing |
| 0:08.3 | competitively. I'd have to go running before school. And on frigid cold New England mornings, |
| 0:14.4 | I'd turn my tap on as hot as I could stand and chug as much of the water as I could before I went out, because I figured that |
| 0:23.4 | the hot water would keep me warm, at least for the first part of my route. This is how 15-year-old |
| 0:29.5 | solved problems. While it did work, I don't recommend copying me because I've since learned |
| 0:36.1 | hot tap water actually has more lead in it. |
| 0:40.4 | Who knew? |
| 0:42.0 | But the reason I bring this up is because today's animal uses the same strategy. |
| 0:49.7 | Experts from the University of Hawaii have tracked the muscle temperatures, depth, and surrounding |
| 0:54.2 | water temperatures of scalloped hammerhead sharks, and they found that their body temperature |
| 0:59.0 | doesn't drop nearly as much as you'd expect when they dive from warm, shallow water into deeper, |
| 1:06.2 | colder water. These are cold-blooded animals, right? Their temperature changes with their environment, |
| 1:11.7 | and at the depth they're diving to, with cold water flowing through their bodies, they should be |
| 1:18.3 | sharksicles. Biologist Mark Royer's theory is that when they dive, they seal their gills |
| 1:26.4 | to trap warm water and prevent the flow of cold water through their bodies. |
| 1:33.0 | Keeping some hot, or at the very least, warm water in your system, is good if you're about to go somewhere cold. |
| 1:39.8 | And it's even better if doing so stops cold water from going through your face, head, and neck. |
| 1:46.1 | For this animal, the cost of running cold water over their lungs is, for a brief period of time, higher than the cost of not breathing. |
| 1:57.3 | Think about that. |
| 1:59.1 | If confirmed, this is a very strange adaptation, but it's not nearly the strangest thing about the scalloped hammerhead shark. |
| 2:08.5 | Svirna Luini. |
| 2:10.9 | I'm Mackin. |
... |
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