Zoologists and Wildlife Biologists. Zoologists and wildlife biologists study animals and other wildlife and how they interact with their ecosystems. They study the physical characteristics of animals, animal behaviors, and the impacts humans have on wildlife and natural habitats. Zoologists and wildlife biologists study animals and other wildlife and how they interact with their ecosystems. They study the physical characteristics of animals, animal behaviors, and the impacts humans have on wildlife and natural habitats. Zoologists and wildlife biologists held about 20,100 jobs in 2012.