The Atlanteans are the first ones known to have experimented with time travel. They built the Time Machine in Atlantis and used it to escape with the survivors into the past during the Vortex-Atlantean War.
During the first game Ecco travels to Atlantis and activates the Time Machine to travel sixty five million years into the past to find the Asterite's missing globe. When Ecco retrieves it, he is suddenly warped back to his time, seemingly by the Asterite. The same thing happens in Ecco 2 when he gathers the final two globes of the destroyed Asterite.
In Ecco 2, Trellia appears to be able to freely travel between time periods. First she travels back to Ecco's time and then transports Ecco to her own era. Later, Ecco is captured by a pair of Vortex Drones and they bring him with them as they time travel to the Dark Future, also without the use of the Time Machine. At the end of the game Ecco defies the Asterite's order to destroy it, and uses the Time Machine once more. He departs to an unknown destination, setting the stage for the future Ecco The Dolphin 3.