Science news this week: Cannibal orcas in Russia, oracle bones that reveal climate catastrophe in ancient China, buzzing black holes and a barefoot volcanologist

This week’s science news was full of bizarre and confusing animal behaviors, with news about Chewed orca fins wash up on a Russian beach indicating cannibalism among apex predators.

There are several subspecies of orcas, and scientists initially assumed that these groups mainly kept to themselves. But genetic evidence, as well as clear tooth marks, strongly suggests that one group occasionally snacks on the other, which could explain why the hunted orcas live in large, tight-knit groups.