Scientist. He was an American zoologist, mammologist, and a pioneer ornithologist or one who studies birds. In 1885 he transferred to the American Museum of Natural History as the first curator birds and mammals, yet most of his work was devoted mainly to the study of mammals. Born oldest of four sons and a daughter, he was a descendent of families dating back to colonial times in New England. He was considered the family’s only “born naturalist.” After selling his childhood collection of various species to fund his education in 1861, he was educated at the Wilbraham Academy before studying under Professor Louis Agassiz at Harvard University, learning his detailed methods of observational data gathering and analysis. Continuing his education, he and a classmate went to Cambridge University in England in 1862. In 1865, he traveled with Agassiz to Brazil in a major expedition to study the Ice Age. Before the American Museum of Natural History, he gained the position of Curator of Birds and Mammals at the Museum of Comparative Zoology at Harvard University in 1870 and concurrently held the same position for the Boston Natural History Society. Besides the trip to Brazil, he was a participant in major expeditions including one along the St. Johns River in East Florida in 1868, the central United States from Kansas to Utah in April of 1871 for Cambridge University, and the newly established Yellowstone National Park in 1873. He made several more minor trips but with his chronic health problems, his last trip was in 1882, then focusing on publication of scientific material. In 1877 he established “Allen’s Rule,” which stated that animals adapted to cold climates have thicker limbs and bodily appendages than animals adapted to warm climates. In 1879, after five years of wedded life, his first wife, Mary Manning Cleveland of Cambridge, died leaving him his only child, Cleveland Allen. Seven years later, he married Susan Augusta Taft of Cornwall-on- Hudson. On March 1, 1888 he hired a young assistant Frank Chapman, who proved to be a champion of birds. He was the first President of the American Ornithological Union, serving from 1883 to 1891, and an editor of the organization’s professional publication, “The Auk,” from 1883 to 1912. He served as editor of the publications of the museum. In 1905 he was a founder, director, and member of the Executive Committee of the National Audubon Society. At the end of his career, with the founding of the American Society of Mammologists in 1919, he was elected as the first Honorary Member of the Society. He published at least 270 titles on mammals, 965 on birds and about 700 book reviews: 5 on reptiles, 9 on zoogeography, 22 on evolution, and 27 on nomenclature. Two of his textbooks were “The Mammals and Winter Birds of East Florida” in 1871 and “The American Bison, Living and Extinct” in 1876. In 1922 the J. A. Allen Memorial Fund was established by the American Society of Mammologists to promote the publishing of articles in the “Journal of Mammology.” He received numerous awards and honors throughout his long career, including Harvard University’s Humboldt Scholarship, Doctorate of Philosophy from the University of Indiana, the Walker Grand Prize from the Boston Society of Natural History, and the Linnaean Society of New York Medal. Among his professional organizations, he became an elected member of the National Academy of Sciences in 1876.