Terraseeding is a form of Terraforming in which a device called a terraseeder exactly replicates the ecosystem of the planet of the species that built the terraseeder. The only species so far that did this on a large scale were the Prae.
Terraseeding exactly replicates the ecosystem of the Terraseeder's home planet. Although they might be in different stages of evolution, even the species are replicated. There are however exceptions, the technology is not flawless. An example of such an exception are the Zansur on Narrasti.