Welcome to Upper Devonian time. During our visit to the Earth of 380 million years ago, we must forget all that is familiar to us and put ourselves in the place of a space traveler who is arriving at a new planet for the first time...(124 kb)
The change of scenery is that dramatic!
Could this really be the Earth, this planet with unrecognizable continents and a northern hemisphere covered by an unending ocean? The six continents and two large oceans we know so well do not even exist yet. And the climate seems hotter than usual; in fact, there is no ice at the North Pole! Not only that, but the days arent even the same length!(60 kb)
A glance at Upper Devonian animals and plants is just as bewildering. Forests are few and scattered in the tropical regions, and do not contain many different types of trees. A greater variety of small plants grow on the ground, however, and if we look very carefully, we may see a few invertebrates hiding and scrambling in the soil litter.
Its quite a different story in the water. Invertebrates are abundant, and so are the many species of fish. But the fish are odd-looking, and very few resemble the species alive today. Aptly titled, the Devonian is known as the Age of Fishes in reference to their evolutionary explosion during this period.
Returning to solid ground, our eye catches a furtive movement: a creature scrambles across an open area, running crookedly, before splashing back into the water. This is one of the tetrapods, the first vertebrates to venture onto land. It doesnt know it, of course, but this tetrapod will bring about a great evolutionary transformation, giving rise some 380 million years later to thousands of tetrapod species, including us!