I read a few of the books in Anne McCaffrey's "The Dinosaur Planet" series. I can't recall -- was it ever explained how dinosaurs ended up on that planet?
2 Answers
The Thek preserved kidnapped rescued the dinosaurs. The planet is a combination petting-zoo & specialist eatery.
"This planet's a zoo, Lunzie. A sanctuary for the dinosaurs. The Thek have been stocking it for millennia — even before the cataclysm," Varian broke in excitedly. "Trizein, and all the other buffs were right, the critters are from Mesozoic Terra."
"Ger was caught in a massive earthquake," Kai said, "and buried so deeply that it was unable to summon help. It had all but exhausted its substance when the Thek started looking for it."
"You see," Varian went on, "the Thek surveyed Old Terra eons ago and were entranced by the dinosaurs. Long before the animals were threatened with extinction by a climatic cataclysm, they had imported them to Ireta which they knew would permanently provide the proper environment. The Thek even brought the Rift grasses for the dinosaurs since Ireta has no natural vitamin A. Dinosaurs are Thek pets." - Dinosaur Planet Survivors
Yes, near the end of the second book, I believe. During (or after?) the audience with the Tor, it comes out that they moved the dinosaurs offworld for 'preservation' purposes.