1.
Homologus Traits
a.
The human and the bat are both vertebrate
mammals. The human walks, talks, and lives an omnivorous life. The bat flies
and lives an herbivorous life.
b.
The bones of the front limbs of both humans and
bats are homologus because they are structured similarly and come from a common
ancestor among vertebrate mammals. The human has a front limb connected to a
hand, which has a purpose of grasping, holding, pointing etc. The bat has a
front limb attached to five digits as well. However, the bat’s digits form a
wing.
c.
The common ancestor between the bat and the
human is the vertebrate mammal. The first vertebrate possessed a skeletal
structure, which I s wear the forearm evolved from.
d.
2.
Analogous Traits
a.
The ape is a vertebrate mammal that lives on
land. The octopus is a cephalopod that lives only in the sea and has eight tentacles.
b.
Both the ape and the octopus have eyes. Eyes in both
species serve the purpose of providing sight vision and the structure of both
specie’s eyes are comprised of retina and nerve fibers.
c.
According to an article from the Harvard Science
department, the ancestry of the ape and the octopus diverged over 700 million years
ago. This common ancestor was a worm like creature with eye-spots not eyeballs.
This ancestor did not possess eye structures similar to that of the ape or the
octopus because they were not necessary. Over hundreds of millions of years,
the ape and the octopus developed eyes for the use of vision, thought the
development of these traits were different between the two species. Their parallel
evolutionary environmental stress for the need to see caused the parallel
evolution of the eye.
d.
I had the same Homologous trait chosen of the bat vs human arms, but i didn't even think of the eyes example for the analogous trait. One difference that i noticed in the homologous traits is that the thumbs on the bad seem to be nearly useless; however the human thumbs are one of the most important fingers of all. And on 1.C.) your "i s wear" should really be fixed to "is where" because on my first read-through i thought it was "i swear"
ReplyDeleteVery good on your explanation of the bat and human forelimb. You did well describing the differences in function arising from the common origin. Great images as well.
ReplyDeleteI love it when students use the eye as their analogous traits! The eye is an interesting structure that has developed independently multiple times in the animal world. You raised a good example of this.
The only caution is that the eye spots you mention is the way most eye evolution begins, so if the common ancestor possessed this, then this could be an example of homologous trait. However, the octopus eye and the human eye have entirely different structures. Frankly, the octopus eye has a better structure! They don't have the blind spot or the backward design that causes us problems. The differences in structure could not have arisen through divergent evolution because the differences are so great and occur at the basic structural level. They arose from parallel evolution.
Good post.
This was a really good post. I enjoyed how you went into detail about the differences and functions each animal uses for their arm. I also liked how you spoke about the traits in very detail.
ReplyDeleteGreat use of analogous traits about the eye. I found this really interesting, I like how you went back millions of years and talked about a common ancestor. But would that make it a homologous trait?
You had great pictures as well and seemed like you knew alot about what you were talking about.
I hate to piggy-back upon what everyone else is saying, but wow, great post! Very informative and "eye" opening. The choice of using the eye as your analogous trait was fantastic as well as educational. Thank you Danielle.
ReplyDeleteI loved how the species you chose for both homologous and analogous traits where vastly different species. This made it very interesting to read the information you provided. I also appreciated the fact that you chose the eye for the analogous trait, something that is possessed by so many organisms, yet I do not think most people even thought about that.
ReplyDelete