What this actually means for the structure of the foot is a question that is still being researched today. It would seem that an accessory navicular is commonly related to pes planus. Frederick Kidner, in 1929, first theorized that the presence of an accessory navicular could be the cause of pes planus.
Successful as they are, Eastern Gray Squirrels live only 11-12 months on average, but some individuals have survived more than ten years in the wild. Factors affecting survival include the severity of winter, abundance of food, and parasites.
Copyright Â© 1996. Eastern Gray Squirrels are the most frequently seen mammal in our area. They are members of the Rodent family, and spend most of their lives in trees. Eastern Gray Squirrels can grow 17 to 20 inches long.hey are easy to see in the Winter, when the nest leaves have turned brown and tree leaves fall to the ground. The trees most commonly used by Eastern Gray Squirrels to live in are White Oak, American Beech, American Elm, Red Maple, and Sweetgum, though they will use others also.