evidence: The first animal likely was a carnivore, new research finds. Humans, along with other omnivores, belong to a rare breed. [...] - Many species living today that are carnivorous—those that eat other animals—can trace this diet back to a common ancestor more than 800 million years ago. [...] The survey suggests that across animals, carnivory is most common, including 63% of species. Another 32% are herbivorous, while humans belong to a small minority, just 3%, of omnivorous animals.