have evolved to handle the lack of buoyancy experienced on land. The hindlimbs were smaller than the forelimbs and unlikely to have borne full weight in an adult, while the broad, overlapping ribs would have inhibited side-to-side movements. The forelimbs had the required range of movement to push the body up and forward, probably allowing the animal to drag itself across flat land by synchronous (rather than alternate) "crutching" movements, much like that of a mudskipper or a seal. It was incapable of typical quadrupedal gaits as the forelimbs lacked the necessary rotary motion range. See also Evolutionary history of life Hynerpeton List of transitional fossils List of prehistoric amphibians Ymeria References Further reading External links Tree of Life Site on early tetrapods Getting a Leg Up on Land Scientific American Nov. 21, 2005, article by Jennifer A. Clack. BBC News: Ancient walking mystery deepens 3D computer model, forelimb maximal joint range, and hindlimb maximal joint range of Icthyostega'' on YouTube, videos by Stephanie E. Pierce, Jennifer A. Clack, & John R. Hutchinson Stegocephalians Devonian tetrapods Transitional fossils Fossil taxa described in 1932 Fossils of Greenland Late Devonian genus first appearances Late Devonian genus extinctions Evolution of tetrapods