Circadian Leaf Movements in Plants

The very first circadian rhythm ever observed was a rhythm of opening and closing of leaves of a mimosa plant. That was a couple of centuries ago (1729, to be exact), reported by astronomer de Mairan. Since then, many researchers, from Charles Darwin, through 19th century botanists Zinn and Hoffer, to 20th century chronobiologist Erwin Bunning, studied this rhythm.

Now, you can see three examples of such movements (check the three plant species on the left sidebar there) on a website that provides the movies. Cool, isn't it?

(hat-tip: Discovering biology in a digital world)