Usually, a belly-up fish isn’t long for this world. But video evidence from the deep ocean suggests that some species of anglerfish — the nightmarish deep-sea fish with bioluminescent lures — live their whole lives upside down. “Just when you think they couldn’t get any weirder, anglerfish outdo themselves,” said Pamela Hart, an associate professor at the University of Alabama who researches fish that live in extreme conditions. Sign up for The Morning newsletter from the New York Times The beha