BUTTERFLIES AND SLEEP.

BUTTERFLIES AND SLEEP. Howard Johnson called my attention to an article on butterflies by Robert Lee Hotz in the Wall Street Journal for February 8. (This link will only work for a short time). Monarch butterflies, traveling at speeds of up to 30 miles an hour, migrate up to 4000 miles each winter to 12 forest groves in Mexico. They turn the trees bright orange—there are 55,000,000 butterflies. It takes two or three generations of butterflies to make the round trip. Scientists have now discovered two genes in monarch butterflies that are light-sensitive and drive their internal clocks. One of them closely resembles a gene found in humans and may provide information on our circadian rhythms of sleepiness. Hotz concludes, “In small things considered is the world revealed.”