HOMOLOGOUS:
A. The two species I am identifying as homologous are, the great ape specifically a gorilla and human. The great ape also known as a Hominidae can be located in Africa or Asia and mostly live in forest area. While the Human or Homo Sapiens vary all around the world and are great contributors to our society.
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| HUMAN & GORILLA PELVIC BONE.
Digital image. Redirect Notice. N.p., n.d. Web. 24 Feb. 2017.
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B. The homologous trait that the great ape gorilla and the human both carry is the Pelvic bone. The main function for this trait is to be able to stand upright. For the Gorilla the other uses for the pelvic bone are to move on all four soles of their feet, and be able to sit upright. The pelvic bone however for the Human is for walking upright vs slouched as the gorilla would be, the human body is supported by the pelvic bone which allows us to move forward with our legs and have motion up and down. The trait differs in position in some cases but also provides upper and lower body support.
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| Lucy comparison Pelvic Bone (size was altered to show height) |
C. The common ancestor for these two species is the Australopithecus Afarensis, also known as a first found hominin which dates back to 3.2 million years ago. Lucy a well known skeleton found then was the first Australopithecus afarensis who began the pelvic bone structure. For this species the pelvic bone was much relied on due to the greater height this type was. It is certain that this species carries this trait because it too was proven to stand and walk upright.
National Geographic. National Geographic Society, n.d. Web. 24 Feb. 2017.
Digital image. Great+ape+gorilla+and+human+pelvic+bone - Google Search. N.p., n.d. Web. 24 Feb. 2017.
ANALOGOUS:
- The two analogous species I am identifying is a Blue Whale and Bat. The whale known to be one of the largest animals is a sea mammal who swims through Pacific, Northern, and Atlantic oceans. The bat or scientifically known as Chiropteran is also a mammal who flies and uses the amazing echolocation to communicate within each other.
Forelimb of Whale & Bat The Trait that these two species have is an appendage called the forelimb, which contains the Ulna, Carpals, Radius. The Blue Whale uses this appendage in their fins to helps them swim through the ocean, and to catch pray, two very important tasks with this trait. The Bat uses theirs to fly and use their wings much like hands to preform things such as climbing and shading themselves or catching prey. They both use their appendage to stay fed, have motion, and fight off any attacks.
Digital image. Redirect Notice. N.p., n.d. Web. 24 Feb. 2017
- The common ancestor most likely could have had this trait because it is a needed body part that helps with mostly all structures to function. These traits are analogous because the whale and bat do not share a common ancestor and adapt to their environments, ocean vs sea well.
"Blue Whale." National Geographic. N.p., 23 Feb. 2017. Web. 24 Feb. 2017."National Geographic Magazine @ Nationalgeographic.com." National Geographic Magazine @ Nationalgeographic.com. N.p., n.d. Web. 24 Feb. 2017.
Okay on your opening description of your homologous species but with regard to this:
ReplyDelete"...are great contributors to our society."
Let's keep the species bias out of descriptions. We need biological description, not judgemental descriptions that I'm sure would find disagreement with all other of our world's species. :-)
With regard to your description of your homologous traits:
"The main function for this trait is to be able to stand upright."
No, actually the main function the pelvis is to connect the hind limbs to the torso of the body. That's it. This is especially important when we recognize that non-human apes possess a pelvis but do NOT walk bipedally.
Reading through the rest of your description, I understand what you were shooting for here, but the problem is you focus on the pelvis in general and not the differences in the pelvis which contributes to the differences in function. Yes, humans are bipedal and gorillas are quadrupedal (not "slouching", by the way), so how do their pelvis structures differ due to these differences in function? This needed to be explained to explain how these homologous traits actually differ, otherwise they are just shared common traits.
With regard to ancestry, no, A. afarensis is not an ancestor of both humans and non-human apes. It is just a hominid in the evolutionary tree of humans. In order to find the common ancestor of both humans and non-human apes, you need to go back to 8-10 mya to find the point where humans and their non-human ape cousins split off.
So if the common ancestor was an archaic ape, that ape was a quadruped and possessed the quadrupedal pelvis and passed it onto these two descendant species, with changes occurring in the traits due to different environmental pressures. That is the information we need to know in order to confirm that these traits are homologous.
Your analogous traits are actually homologous. Let me walk you through this:
Both bats and whales are mammals, which means they share a common mammalian ancestor and we know that these primitive mammals possessed the archaic mammalian forelimb structure. We see this structure in both whale and bat limbs, though both have evolved and developed differences due to differences in environmental pressures and functions. Common genetic origin with differences evolving due to differences in function defines homologous traits, not analogous.
You don't really get into the issue of ancestry in that section of your post. Perhaps if you had explored that a little more thoroughly, you would have recognized the common genetic descent.
Good images.
You contacted me about this so I know you had questions, but I never received a further response. If you have questions, you should email me for explanation and clarification. You don't need to do this on your own and you don't have to just rely on your readings or the assignment module. Your instructor is a resource that you should use as needed.
Hello Professor,
DeleteThank you for all your clarifications, I did struggle with differentiating between the two but thought I had it which is why I did not reach out further. I will be contacting you more thorough the next time I have difficulties, thank you.
Hello Mercedes,
ReplyDeleteI thought your blog was very interesting. I liked how you talked about the homologous traits between apes and humans and how we both have evolved with pelvic bones but we have totally different functions. For the analogous traits like how the professor said whales and bats are both mammals so they originated from a common ancestor who had to be a mammal. But overall it was a very informative blog.
Hello Brian,
ReplyDeleteThank you for that clarification, glad you found it informative though.