J. A. (Joel Asaph) Allen

Born in Springfield, Massachusetts, in 1838, Joel Asaph Allen became an American zoologist, mammalogist, and ornithologist whose work reached across field study, museum science, and taxonomy. He studied under Louis Agassiz at Harvard and joined Agassiz's 1865 expedition to Brazil, an early experience that helped launch his scientific career.

Allen went on to play a major role at the American Museum of Natural History, where he served as the first curator of birds and mammals and later led the museum's Department of Ornithology. He was also the first president of the American Ornithologists' Union, reflecting how central he was to American natural history in his era.

Alongside his museum work, he was a prolific writer and classifier of animals, especially birds and mammals. He is often remembered today for "Allen's rule," proposed in 1877, which suggests that warm-blooded animals in colder climates tend to have shorter limbs or appendages than related animals in warmer places.