Fusion Mammalian

Mammalian mutates have had their DNA fused with the DNA of any vertebrate of the class Mammalia, having the body more or less covered with hair, nourishing the young with milk from the mammary glands, and, with the exception of the egg-laying monotremes, giving birth to live young. This includes the various prehistoric species.

Traits
These mutates tend to have certain behaviors, as well as bodily features, of the mammal that they are fused with. For instance, they will usually be covered in fur, and have the eyes, ears, paws/legs, tails, etc., of the animal. Chiropteran mutates may either have bat wings for arms, or wings sprouting from their backs. Similarly, cetacean mutates may either have whale or dolphin tails growing from their spines, or even instead of an entire lower body.