<P> The aquatic to terrestrial transition of vertebrate organisms occurred in the late Devonian era and was an important step in the evolutionary history of modern land vertebrates . The transition allowed animals to escape competitive pressure from the water and explore niche opportunities on land . Fossils from this period have allowed scientists to identify some of the species that existed during this transition , such as Tiktaalik and Acanthostega . Many of these species were also the first to develop adaptations suited to terrestrial over aquatic life , such as neck mobility and hindlimb locomotion . </P>
when did amphibians begin to colonize land as the first terrestrial vertebrates
the late Devonian era