Tuf Voyaging (1986) by George R.R. Martin

Tuf Voyaging (1986) by George R.R. Martin: A 'paste-up' novel of stories and novellas published over about a decade, Tuf Voyaging tells of several adventures of Haviland Tuf. Tuf lives several thousand years in the future, during George R.R. Martin's 'Thousand Worlds' universe in which humanity has spread out across the galaxy (that's the Thousand Worlds) after the collapse of its Federal Empire. 

Tuf starts off as a quirky but somewhat unsuccessful freighter captain. Personality-wise, Tuf sometimes seems like a first draft for Varys in A Song of Ice and Fire. However, circumstances detailed here put him in sole control of a 30-km-long seed ship, the last of its kind, built by that Federal Empire's Ecological Engineering Corps.

This seed ship, named Ark, can do just about anything biology-related. Thanks to vast libraries of genetic material, genetic manipulation machines, and other doodads, the Ark can unleash planet-destroying plagues, planet-saving biological miracles, or even a few telepathic cats. Tuf finally has a way to make money. And so he does.

This may be Martin's most traditionally Golden-Age science-fiction work. Tuf is quirky and a fairly solid judge of human character, and the stories themselves are the sort of 'science puzzle' stories made popular by writers that include Isaac Asimov and Arthur C. Clarke. Martin seems to be having a lot of fun with the biological puzzles Haviland Tuf faces, and so too the reader.

Even the discovery of the Ark rests on a puzzle being solved -- and Tuf figuring out how to survive that finding. He will then be confronted by a variety of puzzles on different worlds. The puzzles and the solutions are ingenious. It's all breezy science-fiction fun with a few serious points about over-population, religious mania, and cruelty to animals along the way. And, of course, the dangers of invasive species. Especially when that invasive species is humanity. This would make a fine TV series. Come on, guys! Highly recommended.