Jennifer Alice Clack, FRS, is an English paleontologist, an expert in the field of evolutionary biology. She studies the "fish to tetrapod" transition— the origin, evolutionary development and radiation of early tetrapods and their relatives among the lobe-finned fishes. She is best-known for her book Gaining Ground: The Origin and Early Evolution of Tetrapods, published in 2002 and written with the layman in mind.
Clack is curator at the Museum of Zoology and Professor of Vertebrate Palaeontology at Cambridge University, where she has devoted her career to studying the early development of tetrapods, the "four-legged" animals said to have evolved from Devonian lobe-finned fishes and colonized the freshwater swamps of the Carboniferous period.
Clack received a B.Sc. in Zoology from the University of Newcastle upon Tyne in 1970, and a Ph.D. from the University in 1984. She also holds a Graduate Certificate in Museum Studies from the University of Leicester and an M.A. and D.Sc. from the University of Cambridge.
In 2006, Clack was awarded a personal chair by the University of Cambridge, taking the title Professor of Vertebrate Palaeontology. In 2008 she was awarded the Daniel Giraud Elliot Medal from the National Academy of Sciences.[1] She was elected a Fellow of the Royal Society in 2009.[2]
The fossil of Acanthostega she discovered in Greenland in 1987 is a transitional, water-bound primitive tetrapod.