Live sharks discovered inside a live volcano.

National Geographic reveals an ecosystem my 10-year-old son might have dreamed up. It’s all lava, acid and sharks. Inside the cauldron of Kavachi is a “sharkcano”:

“Absolutely, we were scared,” says [Brennan] Phillips, a National Geographic Society/Waitt Grants Program grantee. “But one of the ways you can tell that Kavachi is erupting is that you can actually hear it—both on the surface and underwater. Anywhere within 10 miles even, you can hear it rumbling in your ears and in your body.” No one heard rumbling, so they prepared to go right to the rim of the crater.

Even without such theatrics it’s a dangerous place though. “Divers who have gotten close to the outer edge of the volcano have had to back away because of how hot it is or because they were getting mild skin burns from the acid water.”

So the team strategically deployed their instruments—including disposable robots, underwater cameras, and National Geographic’s deep-sea Drop Cam—to get a broad look at the whole volcano, including what the bottom looks like. Their biggest surprise was that hammerheads and silky sharks showed up on their deep-sea Drop Cam footage—in numbers.

[via io9]