Roe buck - hobby project

I´m trying to learn more about genotypes/phenotypes in animals, particularly about hereditary coat color expressions. I´m personally a huge fan of open-world games but one thing that could still be pushed further is animal behavior (having events such as the great migrations) as well as allowing for slight variations within textures so that not every deer is the exact same shade of brown, or swapping a dark brown summer coat to a white winter coat to make wildlife feel like a part of their world. You got to dream big right?