Scientists have discovered what may be the world's oldest set of footprints. The fossil record may be evidence of a four-legged animal's first steps on land 397 million years ago:
Scientists tell the journal Nature that the fossil trackways even retain the impressions left by the "toes" on the animals' feet.
The team says the find means that land vertebrates appeared millions of years earlier than previously supposed. [...]
They represent the movements of many animals as they scurried around what would have been a tropical muddy shoreline in the Middle Devonian Period of Earth history.
Slabs of carbonate rock are dappled with prints that range in size and detail. Some indentations are obscured where successive animals have trampled over the same patch of ground; but others retain exquisite features of the pads and digits that made them.