If your animal has...

Then...

1. a)

    3 or fewer teeth on each side of its upper jaw?

go to 2.

b)

    At least 9 teeth on each side of its upper jaw?

go to 3.

2. a)

    2 biting teeth on its upper jaw?

go to 4.

b)

    4 biting teeth on its upper jaw?

the skull is from a rabbit.

3. a)

    A skull length of 23 mm or less and brown teeth?

the skull is from a shrew.

b)

    A skull length of more than 23 mm and 44 teeth?

the skull is from a mole.

4. a)

    The roof of its mouth extending past the last molar?

go to 5.

b)

    The roof of its mouth not extending past the last molar?

go to 6.

5. a)

    A skull length of 22 mm or less?

the skull is from a mouse.

b)

    A skull length of more than 22 mm?

the skull is from a rat.

6. a)

    Flat molars (back teeth)?

the skull is from a meadow vole.

b)

    Rounded molars (back teeth)?

the skull is from a deer mouse.