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A. Ambulatory: bears, humans, chimpanzees, gorillas.

B. Cursorial: cats, dogs, hyenas, giraffes, antelope.

C. Ricochetal: kangaroos, kangaroo rats, jumping mice.

D. Jumping: rabbits, hares, elephant shrews.

E. Brachiation: orangutans, gibbons, spider monkeys.

F. Scansorial: tree squirrels, tree shrews.

G. Swimming: seals, whales, dolphins, walruses, muskrats, otters.

H. Flying: only bats.

7. The stance of the elephant is digitigrade, however, elephants could also be considered functionally plantigrade. Confusing? Don't worry we wouldn't ask you to identify the stance of the elephant on a quiz or exam, however, this is a good illustration of how to think about stance and foot morphology. When you look at the elephant skeleton, it looks digitigrade because, as you can plainly see, the metatarsals are not in contact with the substrate. The elephant is resting on the phalanges, and is therefore digitigrade under the strictest definition of stance. What you can't see by looking at the skeleton, however, is that in life, the elephant has a fatty pad of tissue in that space underneath the metapodials. The weight of the elephant is distibuted not only through the phalanges, but also through the metapodials as they contact the fatty pad, and the elephant is functionally plantigrade.

8. This question is really wide open, and there are lots of things that you could say. We posed this question to previous Mammalogy students and collected their responses.
Here are some particularly good answers:

The foot anatomy can tell you what type of locomotion an animal has by the length and position of the metacarpals, metatarsals, and digits. It can tell you whether the mammal walks or runs.

The length of the metacarpals/tarsals relative to the other bones of the forelimbs and hindlimbs and in comparison to each other can give a good idea whether that animal uses its feet for blanace, running, jumping... The size and shape of the phalanges also provide information on whether that animal grips or digs...

If the digits support the weight of the mammal, it is a cursorial mammal and runs much of the time.
If the sole of the foot supports the body weight, the mammal is plantigrade and walks much of the time (ambulatory).
If the mammal has a hoof, only the tips of the digits touch the ground and the mammal is unguligrade.

Every type of locomotion has distinct foot anatomy.
Ambulatory has unmodified metatarsals and metacarpals because they walk on their feet such as the bear.
Cursorial will have longer metatarsals than metacarpals for running, or they will be partially fused to show the presence of hooves.
Saltatorial mammals have longer metatarsals for leaping.
Aquatic mammals have reduced metacarpals and metatarsals, unless they don't use their tail for swimming.

To go back to the Lab 1 Review questions, click here.

To go back to the main review page, click here.

For more information on many of these topics, check out the special topics pages of the Animal Diversity Web.