Question

What is the benefit of the mammalian stance compared to sprawling stance in other groups?

Answer 1

Mammals have three stances based upon how the bones in their feet touch the ground. These stances are plantigrade, digitigrade, and unguligrade. They are represented here by the squirrel, the cyote, and the deer. These stances each have their own benefits and are each suited for different tasks

plantigrade.
They spend a lot of time climbing trees and standing on only two feet, and they require a lot of balance and support. Their unguligrade stance gives them a lot of contact with the ground and relatively large in-lever to out-lever ratio giving them power to jump long distances and scurry up trees

digitigrade .
The coyote is an example of a digitigrade mammal. It serves as an intermediate between plantigrade and unguligrade. With a combination of speed and power, digitigrade animals are often predaors.   The coyote's in-lever to out-lever ratio isn't as powerful as the squirrel's but is larger than that of the deer.

Unguligrade
The deer is an example of the unguligrade stance. With its long bones, small in-lever to out-lever ratio, and small amount of ground contact, the deer has lot of speed and endurance. The unguligrade stance does not allow as much balance or any ability to grasp things with the limbs, but it does give the deer a long stride and some fast legs.