Squirrels chew on tree branches to sharpen and clean their teeth. That's why you may see many small branches on the ground around large trees. They will also chew on power lines for the same reason, this has caused many major power outages throughout the country. A squirrel's brain is about the size of a walnut. The average adult squirrel needs to eat about a pound of food a week to maintain an active life.
Squirrels communicate through a series of chirps.
The frequency, and the duration of the notes communicate everything from laughter to alarm. Their frequency range is normally between .01 KHz. and 10 KHz. These sounds when used in conjunction with tail gestures, form the basis for squirrel communication. If a squirrel has taken up residence in your attic or crawl space, the only practical way to remove them is by trapping. A squirrel will break the shell of a nut with its teeth, then clean the nut by licking it or rubbing on its face before it is buried.