|MadSci Network: Zoology|
Roger, there are alot of scientific papers and textbooks covering limb bone ratios in animals. A good basic book is Milton Hildebrand's "Analysis of Vertebrate Structure", published by John Wiley and Sons. This method of looking at limb bones is a very reliable method for getting a rough idea of how fast an animal could run. Look at the hind limbs of dogs and bears. These animals are closely related, but dogs live (or lived) in open habitats and would run down their prey. Bears live in forests and mountainous areas and do not run (but can sprint briefly faster than a man). Dogs have short femurs and long tibias and metatarsals. They also have long narrow feet and very flexible backs to let them run quickly. Bears are heavy, stiff-backed, broad-footed, and the upper and lower leg bones are almost equal in length. Dogs also walk on the tips of their toes, bears walk with their heels flat on the ground. All good runners (horses, ostriches, cheetahs) walk on their toes. You can't just use one feature to study how an animal ran. As well as the limb bone ratios you have to know how strong bones are. A very good, easy to read summary of this can be found in a Scientific American article written by the world expert on these matters - McNeil Alexander. The title of this article is "How dinosaurs ran", and can be found in the April 1991 issue of Scientific American. Donald Henderson instead of Trevor Cotton
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