WeirdWorld
A few interesting facts from the animal kingdom that might be useful to you, if you want to give the main character a firmer body or faster reactions.
1) The opinion that rhinos have the strongest skin usually persists. But it's not true. Rhinos have 0.5 cm thinner skin than the amphibian hippopotamus (Hippopotamus amphibius), whose skin is 2.5 cm thick (sometimes up to 3 cm). After drying, the hippopotamus skin is so hard that it used to be used to polish the hardest mineral in the world - diamond.
2) The densest known bone in the world has been found in whales. The rostrum (one of the skull bones) of the very rare tropical sperm whale (Mesoplodon densirostris) is very heavy and about four times harder than its other bones. It has a unique structure and chemical composition. More than 35% of bone is calcium, ie 13% more than normal bone. The bone is interwoven with microscopic channels that contain minerals.
3) The star mole (Condylura cristata) achieves the fastest response when finding, recognizing and eating food. It takes an average of 0.227 seconds to swallow the food just identified. And when he does, he swallows food in just 0.14 seconds. By this time, the star mole seems to have reached the very limit of the physiological possibilities of the mammalian nervous system. The key to success is its nose with 22 tactile protrusions, thanks to which it finds out in the dark whether the object is edible or not in 0.008 seconds. Tweezers also help the mole to eat quickly. A special feature are the three brain centers designed for processing tactile stimuli. Mammals usually have only two.
A mole and a hippopotamus are easy to find, but a whale can be a little more difficult.
Although their bones are often on display in a museum
And speaking of museums, I'd be interested if our hero could collect genetic material from dinosaur bones...