In this lab, my partner and I dissected an owl pellet. First, we divided the pellet in half and worked on our halves separately. Using forceps and a probe, we picked apart the owl pellet. We found leg bones and some ribs but unfortunately, there was no skull in the pellet. We put together the bones that we found and came to the conclusion that the animal was a shrew. We knew that the animal had to be a rodent of some kind because we found lots of hair in the pellet, meaning the animal couldn't have been a bird. Next, we looked at the differences in bone structure in shrews, moles, and voles. We found two pieces of a pelvis that looked like that of a shrew because of the loops at the ends of the bones. The shape of the femur of the shrew also matched the femur that we found in the pellet. We also found a lower back leg that could have been that of a vole or a shrew; however, we narrowed it down to a shrew's back leg because of the shapes at the ends of the tibia and fibula, as well as the space between the two bones. So by looking at the pelvis, the upper back leg bones, and the lower back leg bones we found, we concluded that the animal was indeed a shrew.
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| human pelvis |
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| human tibia & fibula |
After putting together the shrew skeleton, we could see that it was actually quite similar to a human skeleton. The pelvis of the shrew was like a stretched out version of a human's. The shrew's had sockets where the femur would connect, the same in a human. The ribs we found were also curved in the same way human ribs are. The tibia and the fibula were also similar to a humans because of their shape. Like a human's, the shrew's fibula was very thin and the tibia was very thick. There were also some small differences in the shrew bones in comparison to a human bone. For example, the pelvis of the shrew didn't have a wide ilium; the shrew's ilium was thin and long. The shrew's fibula and the tibia are connected at the bottom and in a human, the bones are separated. The space between the fibula and tibia in a human are not as wide or as curved as the shrew's.
In this lab, my partner and I dissected an owl pellet. First, we divided the pellet in half and worked on our halves separately. Using forceps and a probe, we picked apart the owl pellet. We found leg bones and some ribs but unfortunately, there was no skull in the pellet. We put together the bones that we found and came to the conclusion that the animal was a shrew. We knew that the animal had to be a rodent of some kind because we found lots of hair in the pellet, meaning the animal couldn't have been a bird. Next, we looked at the differences in bone structure in shrews, moles, and voles. We found two pieces of a pelvis that looked like that of a shrew because of the loops at the ends of the bones. The shape of the femur of the shrew also matched the femur that we found in the pellet. We also found a lower back leg that could have been that of a vole or a shrew; however, we narrowed it down to a shrew's back leg because of the shapes at the ends of the tibia and fibula, as well as the space between the two bones. So by looking at the pelvis, the upper back leg bones, and the lower back leg bones we found, we concluded that the animal was indeed a shrew.
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