Astronomy
Greek astronomer Callippus [b. Cyzicus (Turkey), c. 370 bce, d. c. 300 bce], a student of Eudoxus, is a careful observer who shows that at least 34 spheres are needed to account for the movements of the stars, Moon, and planets. See also 380 bce Astronomy; 140 ce Astronomy.
BiologyTheophrastus [b. Eresus, Lesbos, Greece, c. 372 bce, d. Athens, c. 287 bce] writes major works describing and classifying plants, laying the foundations of botany. See also 350 bce Biology.
Earth scienceTheophrastus classifies 70 different rocks and minerals, doing the first work known on rocks and minerals.
Theophrastus, in The Book of Signs, the first known work on weather forecasting, tells how to predict the weather from common signs, such as a red sky at night or a ring around the Moon. See also 1337 Earth science.
Ecology & the environmentTheophrastus describes relationships within communities of organisms.
