Circadian clocks in a blind fish
Tuesday, September 6, 2011 - 18:30
in Biology & Nature
Do animals that have evolved underground, completely isolated from the day-night cycle, still "know" what time it is? Does a normal circadian clock persist during evolution under constant darkness? A new study tackles these questions by investigating a species of cavefish which has lived for 2 million years beneath the Somalian desert, finding that it has an unusual circadian clock; it ticks with a period of up to 47 hours, and is completely blind.