Teeth Tell A Tale

We can find out about how animals live by looking at their teeth.

Look at the diagram of the dog's teeth and then go to the other examples of skulls and teeth and compare each group of teeth (incisors, canines and molars) to see how they are modified for different types of food.


Dog Skull

Let's look at a dog's skull - a familiar animal, to get an idea of the basic structure of a skull and jaws and the arrangement of teeth.

The upper jaw is formed from the base of the skull. The lower jaw is made up of two bones which are loosely fused at the front and on each side (left and right) is hinged behind with muscles to the back of the skull. Movement of these muscles works the lower jaw up-and-down and in some animals sideways as well.

Teeth are anchored in sockets on both upper and lower jaws and inside are supplied with nerves. Teeth are of several sorts, each shaped for handling different sorts of food. Basically teeth comprise two incisors (for cutting and slicing) at the front on each side of the upper and lower jaws. (This means four upper and four lower incisors). Behind the incisors on each side there is a canine tooth (for piercing, stabbing and holding); thus there are four canines. Behind the canines are two premolars and two molars all of which are shaped for grinding and chewing.

Dogs are carnivorous animals and their canines, like those of cats and all carnivores, are long and pointed. Wild dogs such as the dingo, and other carnivores, catch live prey mainly other vertebrate animals and the canines grasp, jab and hold the prey

In the dog the incisors are comparatively small and unspecialised. However in herbivorous animals the incisors are variously modified and specialised for cutting and tearing grass and other plants or for browsing on higher plants.

After killing their prey with the canines, dogs and carnivores tear, chew and grind the prey with their molars which have “crowns” and grinding surfaces.