The system that circulates blood through the body, consisting of the heart and blood vessels. In all vertebrates and certain invertebrates, the circulatory system is completely contained within a network of vessels. In vertebrates, the lymphatic system is also considered part of the circulatory system.
While a squirrel isnât going to pen the next bestseller or ace a calculus class, the squirrel is smart in his own way. When looking at animal intelligence, humans shouldnât judge animals by human standards.
Being rodents, squirrels eat a wide variety of mostly vegetarian foods -- but some add a few insects or small animals as well. Here is a general list of what squirrels eat -- but each species has its favorite menu. The average life span for a squirrel in the wild is 3-5 years. Their main predators are hawks, owls, cats, and predators of baby squirrels can include snakes, crows and other squirrels.