Something strange is happening to the oceans. As coral reefs wither and fisheries collapse, octopuses are multiplying like mad. As soon as they perceive weakness, they will amass an army and invade the land, too.
Okay, that last statement is probably pure paranoia. But it is a bit unsettling that cephalopods—squids, octopuses, cuttlefish—are booming, and scientists don’t know why. An analysis published today in Current Biology indicates that numerous species across the world’s oceans have increased in numbers since the 1950s.