Scientists filming unexplored depths of the South Pacific have observed a surprising range of animals—including sharks, rays, and jellyfish—living inside Kavachi, a highly active undersea volcano near the Soloman Islands, a remote archipelago east of Papau New Guinea. The animals seem unruffled by what were presumed inhospitable temperatures and acidity.

“The idea of there being large animals, like sharks, hanging out and living inside the caldera of this volcano conflicts with what we know about Kavachi, which is that it erupts,” says ocean engineer (!) Brennan Phillips, who led a team of researchers to the Soloman Islands in search of hydrothermal activity, in the video above. “But when it erupts, there’s no way anything could live in there. And so, to see large animals like this that are living, and potentially they could die at any moment, it brings up lots of questions: Do they leave? Do they have some sort of sign that it’s about to erupt? Do they blow up sky high, in little bits?”

[National Geographic]

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