Throughout history, many animals have undergone a lot of adaptations through what was explained in Charles Darwin’s theory of descent with modification. Animals have gotten bigger, faster, stronger, furrier, smaller, and any possible change you can think of. A popular example of descent with modification is the process wherein brown and white beetles live on the same tree. Due to their inability to camouflage themselves with the tree, the white beetles were never able to survive and pass on their genetics to future offspring. On the other hand, the brown beetles were able to do this effectively. Thus, we were left with an adapted species of beetles. Some animal adaptations can seem weird, but make sense when we think about them. Lactose tolerance is an adaptation that we, humans, acquired a long time ago. When milk became a significant part of people’s diets, those who were able to digest it were at an evolutionary advantage and thus the adaptation occurred (hence the picture of milk above).