Question

Why do you think the bison has two bones in the lower part of its forelimb? (If you're tempted to say that it's for additional strength, consider how much weight the single bone above them, the humerus, supports).  Considering this as a similarity with humans, would this be a homology or an analogy?  

Answer 1

The two bones in the lower part of the forelimbs of the bison have the function of redistributing the weight of the bison, had it been a single bone,it would cause joint dislocation . the weight os the four legged animal is first ditributed from humerus to the two lower bones , and then the heel which distributes it further .

Humans still have two bones in the forearm , but that doesnt help in the same function as the bison . Human was once four legged, so they used the two forearm bones as well as hind limbs.

It cant be called homologous, because humans and bison doesnt share a common ancestor.

It cant be called analogous either because it doesnt assist in the same function, although from different ancestors.