This was primarily an aquatic animal, shown by the limb joints that were set for swimming, the paddle tail and the lateral line sensory apparatus, like that of a fish, which was used for finding its way about underwater. Although the limbs were similar to those of a land-living animal, it is thought that it only occasionally clambered out of the water. The backbone was too weak to support the weight of the animal on land, hut the presence of heavy scales on theunderside shows that it lived close to the ground -presumably in flooded wcrlands and stream margins. It seems likely that Acanthostega spent its time in shallow rivers.(dinosaur costume)
Features: The jaws and fang-like teeth are very fish-like. Both front and back feet consist of at least eight digits, indicating that the standard pattern of five digits had not yet evolved. The bony structure of the shoulder girdle is like that of a fish, allowing the flow of water past it. and this seems to indicate the presence of gills. The backbone and ribs are not stoutly built, suggesting that Acanthostega did not spend much time out of the water.