This question already has an answer here:
Trying to remember a Sci-Fi novel I read close to 20 years ago. The main character was a specially selected man who's lineage may have been tinkered with through the generations. He is made aware that he has the ability to physically modify his body to adapt to any environment or situation. This is done through concentration and mental visualization of the desired modification and ingesting large quantities of food that aid in facilitating these physical changes.
Somehow, he finds himself teleported or transported to an alien planet where the animals are very dangerous. The planet itself, if I remember correctly is many times larger than the Earth is and the main character decides to modify his body to allow him to fly. Unknown to him there is a very large and fast flying predator that nearly kills him. In the process of recovering he modifies his body to something similar to an armored rhinoceros. He manages to jump onto the back of one of these flying predators to speed his travel.
The main character has developed an intrusive probe that he inserts into the brain of the flying predator and in the process discovers it's somewhat intelligent. They travel together for some time but this is where my memory of the book ends.
As far as the title and author are concerned... I believe the author may have had the first name of Peter and that the title began with a "T" beyond that....I have nothing else. Thank you to everyone who may know something and if this same novel has been identified previously, my applogies.