Some fish, it turns out, are morning people. They swim hard during daylight, sleep mostly at night, and tend to live longer. Others drift into daytime napping early in life, move less vigorously, and ...

You’re staring at your aquarium. It’s late. Everything is quiet. And there’s your fish, floating calmly, fins moving slowly, eyes wide open. Are they... asleep? Or just zoning out? Fish don’t come ...