Introduction

Finding animal bones, especially skulls, can be exciting! And everyone loves a good mystery. There are many fascinating things you can learn from animal skulls.

Skull characteristics offer clues about animal diets and helps to classify animals into related groups.

Notice the mystery skull. Do you know what animal it is? To make solving this mystery a bit simpler we will focus on mammals only, though some of these concepts apply to other groups of animals as well.

What can we learn from this skull, even if we have no idea what animal it is?

Here are a few key questions to ask: Where are the eye sockets (orbits) located? What do the teeth look like – are they all sharp or mostly flat? Does the jaw have a large space with no teeth? How long is the snout?

Teeth as Tools

Teeth are among the features on a skull that we notice first. What can teeth tell us?

It helps to think of teeth as essential tools that animals need to survive.

The arrangement of teeth in the skull is called dentition, and it provides a lot of information about the animal that the teeth belong to. The shape and structure of the jaws are another clue.

Teeth and jaws can help decipher whether a mammal is a carnivore, herbivore, or omnivore.

Carnivores, or meat-eaters, rely on canines, carnassial teeth, tight jaws that move up and down (and not side to side) to catch prey and consume meat.

Carnassial teeth are specialized premolars or molars that are meant for tearing or shearing.

In contrast, herbivores eat plants, and use incisors to cut vegetation. Their canines are either less noticeable than in carnivores or non-existent.

There is a space between herbivore incisors and cheek teeth (premolars and molars) called a diastema, where vegetation can be held or carried.

Premolars and molars are flatter and made for grinding.

Omnivores have both kinds of teeth – they have prominent incisors for biting and cutting, relatively long and sharp canines for piercing prey, and flatter molars for grinding vegetation.

Omnivores generally have a tighter jaw joint that doesn’t allow much movement side to side, so their jaws are often more like carnivores than herbivores.

Which mammals smell well

Eye Arrangement

The placement and size of the orbits, or eye sockets provides important hints about the animal in question. Are the eye sockets on the side of the head, like caribou and other ungulates?

Or are both in front, like a wolverine? Prey species rely on being able to detect the movement of predators to survive.

Eyes are on the side of the head, and each eye can generally see close to 180 degrees peripherally around them, meaning prey species can fully monitor their surroundings.

Eyes in the front allow predators to have binocular vision, which means both eyes face the same direction and perceive a three-dimensional image of their surroundings. Binocular vision allows excellent depth perception for spotting and capturing prey.

If a mammal has particularly large orbits, it may indicate large eyes. What animals can you think of that need particularly large eyes?

Perhaps animals that need to see in the dark – either at night or in dark or murky water - flying squirrels, cats, and seals/sea lions to name a few.

Orbits positioned high on the skull may indicate that the species spend time in aquatic environments, where their eyes can remain above water while most of their head/body is submerged.

A beaver below is an example (skull overlay illustration by Sarah DeGennaro).

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