Owl Pellet Lab

In this lab, Michelle and I analyzed an owl pellet, which is the regurgitated remains of a barn owl's meal (a yummy rodent or bird) that could not be digested. When we first unwrapped the pellet, it looked like a lump of fur. It felt like I was petting my old pet hamster. After we began examining the inside and carefully crumbling away the dark fur parts to expose the bone, it was evident that we had multiple rodents in our pellet, as shown by the 11 humerus and femur bones we found. We believed we had vole bones in our pellet. Our reasoning for this was: the shape of the humerus bones, which were long but thin and had the defining triangle spike on the side; the shape of the tibias and fibulas, which were fused in our case; and most notably the shape of the skull pieces, which had the large sharp front teeth and the tiny back teeth, as well as the deeper eye socket. These characteristics clearly point to a vole, as the other rodents ehad differently shaped humerus bones (the shrew's lacked the spike on the side and the mole's was vaguely circular), fibulas and tibias, or skulls (the shrew had an indiscernible eye socket, and the mole's was also more shallow).
The bones we found had some similarities and differences to a human skeleton. The human humerus is also in the shape of a long line. Both the vole and the human humerus has two wider epiphyses at each end of it. The skull also has the same basic features, such as an eye socket, the sharp teeth like the canine teeth in humans, and the flat molars near the back of the jaw. However, the vole has the distinct triangle on the side of the humerus, which humans lack. The radius and ulna are also very different in the vole, with the ulna being remarkably thin in comparison to the radius. (Maybe vice versa.) The tibia and fibula were also fused in the vole and not in a human.