Critical Threshold

They call them the "e;rat-catchers."e; They're the crew of the spaceship Daedalus, which an economically destitute Earth has dispatched on a mission to re-establish contact with its far-flung, long-lost colonies in space. Alex Alexander, the ship's biologist, together with his staff, must help solve the mysteries of human and alien ecosystems that he encounters light-years from home. ...