Subtitles section Play video Print subtitles Today I'm going to tell you about one of my favorite creatures to ever grace this planet. It's a frog that's pretty bizarre but also weirdly sweet and adorable. Sadly, it went extinct just before I was born, so I thought I'd never get the chance to see it. But a few years ago, scientists tried to bring it back from the dead. I'm Anna and this is Gross Science. Gastric-brooding frogs were first found in Queensland, Australia in 1972. They looked pretty normal—just your average brownish, greenish frog. But there was nothing average about how they gave birth. A female frog would lay her eggs, and a male frog would fertilize them externally. So far so normal. But then, the mother frog would swallow the eggs—around 40 of them! You'd think this would be a terrible idea. After all, stomachs—whether they be frog or human—usually contain strong acid to break down your last meal. But the eggs likely contained a chemical that made the mother's stomach stop producing acid. That meant the mother couldn't eat during her pregnancy, which from a human perspective seems awful, but the frogs seemed to make do. Eventually, tadpoles would hatch from the eggs. And the tadpoles would release mucus that contained more of that acid-blocking chemical. The babies would continue to grow in the stomach for another 6 weeks, getting so big that they'd compress the mother's lungs. Luckily, these frogs could also breathe through their skin, so the mothers didn't suffocate. Finally, the tadpoles would metamorphose into baby frogs, and the mother would vomit them up—usually one at a time over a few days. Though, when provoked some were known to projectile vomit all their babies out at once. While barfing up your babies sounds...horrible...it's kinda sweet when you think about it. Gastric-brooding, as this strategy is called, is a way to keep your babies close to you and safe while they're most vulnerable. It's really a lot like human pregnancy…only the babies come out the other end… Anyway, there were two species of these frogs, but both went extinct by the mid-80s. The culprit was likely an invasive fungus—one that poses a major threat to amphibians worldwide, and that humans likely helped to spread around the globe. It's called chytrid fungus and it affects a frog's skin. Because frogs use their skin for crucial functions like breathing, staying hydrated, and regulating their temperature, the parasite can easily kill its victims. And it's highly contagious—by 2013 it had put 42% of the world's frog species in danger. Losing all these frogs would be, in a word, devastating. Not only would it have major impacts on ecosystems worldwide, and be a loss of beautiful biodiversity, but there is so much we still have to learn from these creatures that might be beneficial to human health and well-being. Take the gastric-brooding frog. If we'd had more time to study it, maybe we could have learned more about how it turns off stomach acid production, potentially revealing some insights that could help humans with GI problems. Consequently, back in 2013, some scientists began a project to resurrect the gastric-brooding frog. They took cells from a frozen specimen, cloned the DNA into the egg of another frog species, and ended up creating a living gastric-brooding frog embryo. It only survived for about three days, but they haven't given up trying. And it's made some researchers hopeful that “de-extinction”—the process of bringing extinct species back to life—will one day be a solution for reviving at least some of the valuable biodiversity we've lost, often due to humans' impact on the environment. Obviously, this is a controversial idea. And, I think most scientists would agree that de-extinction is a last-gasp effort in conservation. It in no way means we should stop protecting and preserving the at-risk species we have. That said, while I can't speak to the ethics of the situation, I will admit that there's a pretty big part of me that would love to see a gastric-brooding frog vomiting up its babies. Ew.
B1 US frog acid extinct mother fungus stomach Meet The Frog That Barfs Up Its Babies 167 4 薛明璟 posted on 2018/01/18 More Share Save Report Video vocabulary