CLOSE
Australian Museum
Australian Museum

Meet the Tadpole with Teeth

Australian Museum
Australian Museum

In 2008, an international team of scientists was trudging through the forests of Vietnam’s Bidoup-Nui Ba National Park when they found a frog they didn’t recognize. Actually, no one recognized it, at least not formally. It was new to science and the species had never been described or named. 

The scientists took care of that, dubbing the frog the “Vampire Flying Frog,” Rhacophorus vampyrus, in 2010. A new species is usually pretty exciting, but the more interesting part of the story is maybe not the frog, but its tadpoles and the way the species got its unique name. 

When the researchers discovered the frog, they also found a hole in a nearby tree. The hole was filled with water, and the water was filled with the frog’s tadpoles. They were tiny and black, and looked a little odd. When the scientists got a few back to the lab and put the tadpoles under a microscope, they realized that odd was an understatement.

The tadpoles’ mouthparts weren’t like anything they’d seen in other species. On each side of the mouth, there was a large, keratinized hook-like bit that stuck out, and then curved down. To the scientists, they looked like fangs. 

Jodi Rowley, a herpetologist at the Australian Museum and lead author on the paper describing the species, is reasonably sure that the tadpoles aren’t blood suckers. The strange “fangs,” the fact that Rhacophorus have webbing on their feet that allows them to glide through the air, and the fact that this new species is nocturnal, though, all make its common name pretty fitting. 

Rowley’s latest research on the frogs, published late last year, digs a little deeper into why the tadpoles have such impressive chompers. Most tadpoles have “oral discs” that are sort of beak-like and built for scraping up algae or consuming small prey. Most other frogs also lay their eggs in a stream or pond. The Vampire Flying Frogs lay their eggs suspended in foam nests in the inside of water-filled tree holes, though, and the tadpoles’ fangs seem to be a way to deal with this unique home. 

These holes aren’t very big, and there’s not much there to eat, so the momma frog returns to the nest occasionally and leaves her little ones a bunch of unfertilized eggs to eat. Rowley thinks that the weird mouthparts are used to snag the eggs, move them around and position the could-have-been-siblings to be swallowed whole.

While Rhacophorus vampyrus might have the monstrous name, weird dentition isn’t exactly a novelty among frogs. A number of species sport tooth-like bone protrusions in their mouth that they use for nabbing fast-moving prey. 

Primary image courtesy of the Australian Museum.

nextArticle.image_alt|e
iStock
arrow
Big Questions
What's the Difference Between Gophers and Groundhogs?
Gopher or groundhog? (If you chose gopher, you're correct.)
Gopher or groundhog? (If you chose gopher, you're correct.)
iStock

Gophers and groundhogs. Groundhogs and gophers. They're both deceptively cuddly woodland rodents that scurry through underground tunnels and chow down on plants. But whether you're a nature nerd, a Golden Gophers football fan, or planning a pre-spring trip to Punxsutawney, Pennsylvania, you might want to know the difference between groundhogs and gophers.

Despite their similar appearances and burrowing habits, groundhogs and gophers don't have a whole lot in common—they don't even belong to the same family. For example, gophers belong to the family Geomyidae, a group that includes pocket gophers (sometimes referred to as "true" gophers), kangaroo rats, and pocket mice.

Groundhogs, meanwhile, are members of the Sciuridae (meaning shadow-tail) family and belong to the genus Marmota. Marmots are diurnal ground squirrels, Daniel Blumstein, a UCLA biologist and marmot expert, tells Mental Floss. "There are 15 species of marmot, and groundhogs are one of them," he explains.

Science aside, there are plenty of other visible differences between the two animals. Gophers, for example, have hairless tails, protruding yellow or brownish teeth, and fur-lined cheek pockets for storing food—all traits that make them different from groundhogs. The feet of gophers are often pink, while groundhogs have brown or black feet. And while the tiny gopher tends to weigh around two or so pounds, groundhogs can grow to around 13 pounds.

While both types of rodent eat mostly vegetation, gophers prefer roots and tubers (much to the dismay of gardeners trying to plant new specimens), while groundhogs like vegetation and fruits. This means that the former animals rarely emerge from their burrows, while the latter are more commonly seen out and about.

Groundhogs "have burrows underground they use for safety, and they hibernate in their burrows," Blumstein says. "They're active during the day above ground, eating a variety of plants and running back to their burrows to safety. If it's too hot, they'll go back into their burrow. If the weather gets crappy, they'll go back into their burrow during the day as well."

But that doesn't necessarily mean that gophers are the more reclusive of the two, as groundhogs famously hibernate during the winter. Gophers, on the other hand, remain active—and wreck lawns—year-round.

"What's really interesting is if you go to a place where there's gophers, in the spring, what you'll see are what is called eskers," or winding mounds of soil, Blumstein says [PDF]. "Basically, they dig all winter long through the earth, but then they tunnel through snow, and they leave dirt in these snow tunnels."

If all this rodent talk has you now thinking about woodchucks and other woodland creatures, know that groundhogs have plenty of nicknames, including "whistle-pig" and "woodchuck," while the only nicknames for gophers appear to be bitter monikers coined by Wisconsin Badgers fans.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

nextArticle.image_alt|e
Google
arrow
Animals
Watch Christmas Island’s Annual Crab Migration on Google Street View
Google
Google

Every year, the 45 million or so red crabs on the remote Australian territory of Christmas Island migrate en masse from their forest burrows down to the ocean to mate, and so the female crabs can release their eggs into the sea to hatch. The migration starts during the fall, and the number of crabs on the beach often peaks in December. This year, you don’t have to be on Christmas Island to witness the spectacular crustacean event, as New Atlas reports. You can see it on Google Street View.

Watching the sheer density of crabs scuttling across roads, boardwalks, and beaches is a rare visual treat. According to the Google blog, this year’s crabtacular finale is forecasted for December 16, and Parks Australia crab expert Alasdair Grigg will be there with the Street View Trekker to capture it. That is likely to be the day when crab populations on the beaches will be at their peak, giving you the best view of the action.

Crabs scuttle across the forest floor while a man with a Google Street View Trekker walks behind them.
Google

Google Street View is already a repository for a number of armchair travel experiences. You can digitally explore remote locations in Antarctica, recreations of ancient cities, and even the International Space Station. You can essentially see the whole world without ever logging off your computer.

Sadly, because Street View isn’t live, you won’t be able to see the migration as it happens. The image collection won’t be available until sometime in early 2018. But it’ll be worth the wait, we promise. For a sneak preview, watch Parks Australia’s video of the 2012 event here.

[h/t New Atlas]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios