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a.) The two different species that possess the homologus traits I chose are:
The bones of a human skeleton and the bones of a bat's front limb.
b.) Both the human skeleton and bat's front limb differ in size but they also have the same overall structure, and both limbs end in five digits. Both also have a forearm in which consists of the following bones: Humerus, Radius, Ulna, Carpals, Metacarpals, and Phalanges. Some differences are that human bones are covered by skin whereas bats are covered by hair. Also, humans use their forearm to write, play the piano, pick up objects, etc., and bats use theirs to fly.
c.) It isn't really known who, generally, the common ancestor of these two species was, however, it is known that they do come from common ancestors. According to http://bioweb.cs.earlham.edu/9-12/evolution/HTML/live.html, they should and they do share common anatomical traits. "More significantly, they are derived from the same structures in the embryo. Structures that are embryologically similar, but have different functions, are called homologous structures. A comparison of homologous structures indicates that they are quite similar. This suggests that they evolved from a common ancestor."
d.)
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| Bat's front limb |
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| human limb |
2. a.) The two different species that possess the analogous traits I chose are: Sweet potato and potato
b.) Both have the same function but serve the same purpose - they are both a food, both can be planted, and both can be eaten.
c.) Both did for the fact that they are a vegetable but what makes them different is that one is a stem (potato) and the other a root (sweet potato).
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| Potato |
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| Sweet Potato |
I've always loved comparing the human upper limb to the bat upper limb. But do you think their common ancestor was mammalian? Or farther back? Reptilian?
ReplyDeleteBoth potatoes and sweet potatoes are root tubers (not part of the stem), so actually these are examples of homologs as well with a common evolutionary origin. Good try, though. I like it when people get away from animals and try something different.
If I had to guess, I'd go with mammalian because most mammals have hair or fur, another characteristic is the ability to produce milk in order to feed their babies.
ReplyDeleteRegarding the potato and sweet potato. In my research, I found that although the potato is grown in the ground, it really is a stem (http://hcs.osu.edu/hcs300/anat1.htm). And the sweet potato is a root (http://gardening.about.com/od/vegetables/p/Sweet-Potatoes.htm).
I too wanted to get away from the animal and try something different :).
Wow, you got me on that one (the potato). Learn something new every day!
ReplyDelete