Gates of Eden

Before the hyper-space vessels could go from planet to planet, stations had to be set up. And that meant manned spaceships cut off from Earth for decades.
The explorer vessel Ariadne had gone toward galactic centre and was considered lost - until its call came in appealing for a xenobiologist.
Their new world was all swamp. As far as could be seen, there was no intelligent species. Yes, this was ala...