Some fossil footprints of Apatosaurus caused puzzlement when scientists realized that they were the imprints of only the front legs of this vast reptile. They realized that the Apatosaurus must have been wading along in shallow water, pushing itself along with its long front legs while its hind legs floated clear of the muddy bottom.
At one time scientists thought that sauropods were far too large to have walked on land, and that they must have lived entirely in swamps where the water would support their weight. We now know this is incorrect, and that these giants were normally land-dwellers. In fact, they would probably have become stuck in soft mud due to their enormous weight, and preferred to live on dry land.
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