Skull Duggery in the Hedgerow

White tail deer skull


It's pretty common to find one or more skulls when out walking the dogs . Skulls can tell you quite a lot if you look at them carefully -- the species of the animal, and the sex and age as well.

The skulls, above and below, are of common white tail deer. Deer do not have front teeth on their top jaw -- a feature they share with both cattle and sheep.

As with most herbivores, a deer has a loose bottom jaw that allows the teeth to slide left to right while chewing -- and a long row of molars at the back for grinding up plant material

Note that a deer's eyes are located on the side of the head. This feature is common to most herbivores, from rabbits to buffalo. Side eye sockets give a grazing animal a very large field of peripheral vision necessary to avoid predators (human, wolves, bobcats, coyotes), but a very limited sense of depth perception.

Predators, such as wolves, dogs, coyotes, fox, cats, bears and humans have eye sockets to the front which improves depth of field and focus which are necessary for successful hunting.

The age of a deer at death can be approximated by looking at the third premolar on the skull. Up to about 19 months of age, the third premolar has three cusps, but at about 20 months of age the third premolar is replaced with a tooth that has two crests.

At 2 1/2 years of age all the teeth are present and none really show any appreciable wear. All the cusps are relatively pointed and sharp.

At 3 1/2 years of age the crest of the teeth are starting to show some wear and becoming a bit blunt, and the last cusp on the last tooth looks a bit concave.

At 4 1/2 years the teeth are very worn, and the last cusp on the last tooth is sloped outward and downward.

At 5 1/2 years of age the crests of the teeth are nearly worn smooth and the dentine (the black part of the tooth) is wider than the enamel.

At 6 1/2 years of age the crest of the teeth are practically gone and most of the teeth will look quite flat.

At 7 1/2 years of age all the teeth are worn flat and show tremendous wear. Very few deer live much beyond this age.