Jeopardy! category: CRITTERS (17-09-2014)
$1600 clue: This largest sea turtle is the only one that lacks a hard shell, having instead skin with tiny bone plates
The gist: When you’re the biggest extant turtle species and the fourth largest reptile, you can get away with looking a little different.
The leatherback turtle lives throughout the world’s tropical seas, with many major nesting sites on the eastern coast of the Americas. They can grow to be almost three metres long, with foreflippers just a bit shorter than their length, and they have been recorded as the fastest reptiles on Earth, reaching over 35 km/h in the water when sprinting. Their most distinguishing feature, though, is of course their lack of the hard shell that’s mentioned in the clue. While leatherbacks aren’t the only turtle species without a hard shell (the even-more-aptly-named softshells lack them too), they are the only saltwater species without them. Being so huge, they don’t have much need for a hard shell to protect them once their grown, and when they’re still hatchlings a shell isn’t likely to protect them from from predators anyway. Instead, their sleek, oily carapaces are highly hydrodynamic, and their thick skin and osteoderms (the technical term for the “tiny bone plates” mentioned in the clue) are more than sufficient as to protect them – though they still face threats from very large animals (including occasional land predators when the females beach to lay their eggs), they’re fierce enough to scare most off once they reach adult size. Uniquely among reptiles, they’re also able to maintain a high body temperature through their metabolism, instead of through sun-bathing, though recent studies have suggested it’s not quite accurate to call them “warm-blooded” as some have done.
Apropos of Tuesday’s post, leatherbacks are also long-distance travelers – one individual has been tracked swimming from Indonesia to the U.S., about 20,000 kilometres, over a little under two years. They tend to follow close behind their favourite prey, jellyfish, which makes up almost the entirety of their diet – and they’re crucial in keeping jellyfish populations under control. Sadly, they also have a habit of confusing plastic bags for jellyfish, which can kill them by obstructing their digestive tracts and play havoc with their sexual maturation. This and other pollutions, plus habitat destruction and hunting, have severely reduced global leatherback populations and the animal is currently classified as “Vulnerable” by the IUCN.
The clue: This one was a triple stumper – the clue gives more than enough information to get the correct response if you’re familiar with the animal, but doesn’t give any hints as to the name of the animal, making it fairly tough (compare yesterday’s clue’s monster” hint, for example).
In Jeopardy!: The leatherback shows up in ten regular clues and one FJ! clue in the J!Archive. The most common theme is the turtle’s size, either giving a specific figure or calling it the largest turtle, given in four clues. Surprisingly, just two regular clues and the FJ! reference their descriptive names, which I would have thought would be at least tangentially mentioned in most of the clues. One-off themes include their jellyfish diet, their ribs (which most turtles lack, having evolved into their hard shells), and their lack of claws.