Joseph Leidy: Difference between revisions

Joseph Leidy (September 9 1823 – 30 April 1891) was an American paleontologist.

Leidy was professor of anatomy at the University of Pennsylvania, and later was a professor of natural history at Swarthmore College. His book Extinct Fauna of Dakota and Nebraska (1869) contained many species not previously described and many previously unknown on the North American continent.

Leidy named the holotype specimen of Hadrosaurus foulkii, which was recovered from the marl pits of Haddonfield, New Jersey. It was notable for being the first nearly-complete fossilized skeleton of a dinosaur ever recovered. The specimen was originally discovered by William Parker Foulke.

Leidy was also a renowned parasitologist, and determined as early as 1846 that trichinosis was caused by a parasite in undercooked meat [1]. He was also a pioneering protozoologist, publishing Fresh-water Rhizopods of North America in 1879 - a masterpiece that is still referenced today.

Joseph Leidy was born on September 9, 1823, to an established Philadelphia family. At the time, scientific investigation was largely the province of wealthy amateurs.

He married Anna Hardin. Their marriage was childless, and they eventually adopted an orphaned girl.

In 1846, Leidy became the first to use a microscope to solve a murder mystery. A man accused of killing a Philadelphia farmer had blood on his clothes and hatchet. The suspect claimed the blood was from chickens he had been slaughtering. Using his microscope, Leidy found no nuclei in these erythrocytes (human erythrocytes are anucleate). Moreover, he found that if he let chick erythrocytes remain outside the body for hours, they did not lose their nuclei. Thus, he concluded that the blood stains could not have been chicken blood. The suspect subsequently confessed.

• The Joseph Leidy on-line exhibit at the Academy of Natural Sciences
• The Joseph Leidy Microscopy Portal

• 1823 births
• 1891 deaths
• American paleontologists
• Paleontologist stubs
• American biologist stubs

• All stub articles