Homologous and Analogous Traits
Homologous Traits
a. The two species I have selected are the bird and human. These two species are totally different now, but their ancestors may have shared some traits that were homologous based off adaptations and environment change. The bird is classified as a chordate because it has a backbone, while the human is a mammal or primate. So, with this in mind, the two species are distinctively different.
b. The homologous trait between each specie is the bone structure of their hands.The structure in the bird's wings and the anatomy in the human's hands are very identical, suggesting that they are homologous traits. In birds, they possess a wrist, elbow, hands, and humans have the exact same. However, the actual function and shape is very different because birds need to have elongated fingers in order to fly. Obviously, humans don't have this shape. Despite this, the bone anatomy in the bird and human suggest that the two species did evolve from a common ancestor and went through divergent evolution throughout the years. Due to the similar bone structure in the birds compared to humans, we can conclude that wings originally derived from the human hand.
c. The common ancestor for the two species are early amniotes. These are a group vertebrates who eventually branched out into reptiles, birds, and mammals. Early birds developed similar hand structure to humans because of their common ancestor in the amniotes.
d
.
Analogous Traits
a. The two species that possess analogous traits are the platypus and the duck. These two species are very different. The platypus is a mammal that had evolved long after birds and other mammals. The duck is a type of bird that evolved way before the platypus. This provides evidence of analogous traits because they evolved at different times, suggesting that they did not share a common ancestor.
b. The analogous trait in each species is the formation of the bill of a bird. The duck formed a bill in order to extract water and nutrients that were previously tough to obtain. So, they evolved to grow a longer mouth to better provide for themselves. Similarly, the platypus developed a bill for the exact same reason: to get easier access to food and water with a longer mouth. However, this did not suggest that they were all from a common ancestor though. The platypus and duck share no other traits, thus proving the analogous traits and structure. Having a similar evolution and function does not suggest a common ancestor.
c. I guess we can say that these two are part of the amniote family. However, this specie had eventually branched out into birds and mammals respectively. The formation of this analogous trait was evolutionary. This means that these animals developed a bill due to natural selection and Darwin's principles of evolution. With this in mind, I don't think that the amniotes had possessed these analogous traits.We know these traits are analogous because the original platypus had not possessed a bill. it wasn't until evolution had caused the formation of bills in the platypus. The same goes for the duck. Without evolution, the duck would not have a bill. All in all, the ancestors of these species most likely did not have these selected analogous traits because each specie( Platypus and duck) had gone through changes in different periods of times. In addition, theses traits are not genetically linked because the platypus is a mammal and the duck is a bird.
d.
This is a duck-billed platypus
/duck-big-bill-59ef8e5068e1a2001072c89e.jpg)
This is a duck
https://www.quora.com/What-is-the-most-recent-common-ancestor-of-birds-and-humans
https://www.researchgate.net/figure/A-Human-hand-B-bird-and-C-bat-forelimb-comparison-Wings-evolved-from-the-same_fig1_328511918
https://education.seattlepi.com/examples-homologous-traits-vertebrates-4680.html
a. The two species I have selected are the bird and human. These two species are totally different now, but their ancestors may have shared some traits that were homologous based off adaptations and environment change. The bird is classified as a chordate because it has a backbone, while the human is a mammal or primate. So, with this in mind, the two species are distinctively different.
b. The homologous trait between each specie is the bone structure of their hands.The structure in the bird's wings and the anatomy in the human's hands are very identical, suggesting that they are homologous traits. In birds, they possess a wrist, elbow, hands, and humans have the exact same. However, the actual function and shape is very different because birds need to have elongated fingers in order to fly. Obviously, humans don't have this shape. Despite this, the bone anatomy in the bird and human suggest that the two species did evolve from a common ancestor and went through divergent evolution throughout the years. Due to the similar bone structure in the birds compared to humans, we can conclude that wings originally derived from the human hand.
c. The common ancestor for the two species are early amniotes. These are a group vertebrates who eventually branched out into reptiles, birds, and mammals. Early birds developed similar hand structure to humans because of their common ancestor in the amniotes.
d
.
Analogous Traits
a. The two species that possess analogous traits are the platypus and the duck. These two species are very different. The platypus is a mammal that had evolved long after birds and other mammals. The duck is a type of bird that evolved way before the platypus. This provides evidence of analogous traits because they evolved at different times, suggesting that they did not share a common ancestor.
b. The analogous trait in each species is the formation of the bill of a bird. The duck formed a bill in order to extract water and nutrients that were previously tough to obtain. So, they evolved to grow a longer mouth to better provide for themselves. Similarly, the platypus developed a bill for the exact same reason: to get easier access to food and water with a longer mouth. However, this did not suggest that they were all from a common ancestor though. The platypus and duck share no other traits, thus proving the analogous traits and structure. Having a similar evolution and function does not suggest a common ancestor.
c. I guess we can say that these two are part of the amniote family. However, this specie had eventually branched out into birds and mammals respectively. The formation of this analogous trait was evolutionary. This means that these animals developed a bill due to natural selection and Darwin's principles of evolution. With this in mind, I don't think that the amniotes had possessed these analogous traits.We know these traits are analogous because the original platypus had not possessed a bill. it wasn't until evolution had caused the formation of bills in the platypus. The same goes for the duck. Without evolution, the duck would not have a bill. All in all, the ancestors of these species most likely did not have these selected analogous traits because each specie( Platypus and duck) had gone through changes in different periods of times. In addition, theses traits are not genetically linked because the platypus is a mammal and the duck is a bird.
d.
This is a duck-billed platypus
This is a duck
https://www.quora.com/What-is-the-most-recent-common-ancestor-of-birds-and-humans
https://www.researchgate.net/figure/A-Human-hand-B-bird-and-C-bat-forelimb-comparison-Wings-evolved-from-the-same_fig1_328511918
https://education.seattlepi.com/examples-homologous-traits-vertebrates-4680.html
The opening section in both the homologous and analogous areas asked for a description of your species, not just identification. This would help your reader understand the environment and behavior of the species to better understand why their traits evolved the way they did. Needed to be expanded.
ReplyDeleteHomology: Note that both humans and birds are chordates since we both have a spinal column, just as we are both 'vertebrates', possessing a vertebral column. What are some of the differences between these two species? How are they unique?
"Due to the similar bone structure in the birds compared to humans, we can conclude that wings originally derived from the human hand."
Stop! Back up. As birds and humans are in completely different evolutionary lines, how did the bird wings evolve from humans? They didn't. Both arose from their common ancestor, namely an archaic reptile who possessed the "digits" of the general primitive reptilian front foot.
Additionally, while you discuss the structure and related function of the bird, you don't do this for humans. How is the structure of the human hand mirrored in its function? This was the purpose of this section. No additional ancestry connections needed to be made here.
"Amniotes" is a general clade, not a specific group of ancestral organisms. Can we get a little more specific here? As explained above, since humans are mammals, who arose from reptiles, and since birds also arose from reptiles, the common ancestor here was an archaic reptile. And we also know from the fossil record that early reptiles possessed that generalized mammalian forelimb structure and passed that onto these two descendant species, with changes concurring over time due to differences in the environment (flight vs. manipulative). That is what we need to know to confirm common genetic origin and confirm homology.
Analogy: The duck and the platypus provide a very interesting comparison. I would have liked more information in this initial section to lay the groundwork for explaining why these organisms possess convergent traits.
"This provides evidence of analogous traits because they evolved at different times, suggesting that they did not share a common ancestor."
As explained in the guidelines, ALL organisms share a common ancestor if you go back far enough.
Good description of similarities in structure and function, but you didn't need to start talking about ancestry here. The question isn't about how these traits don't mean there was a common ancestor. The question is, how does ancestry help us confirm analogy. Don't put the cart before the horse.
So how can we use ancestry to confirm that these traits are indeed analogous?
"This means that these animals developed a bill due to natural selection and Darwin's principles of evolution. With this in mind, I don't think that the amniotes had possessed these analogous traits."
Neither of those mean that the ancestor didn't possess this trait.
"We know these traits are analogous because the original platypus had not possessed a bill. "
Ah, now that is on the right track. The information we need to confirm analogy is the fact that the bill structure is a uniquely *derived* trait of the platypus and also of the duck (and other aquatic water fowl). It was not a trait found in other mammals or in other non-aquatic birds and not found in their reptilian ancestors. That is the information we need to confirm analogy.
Good images.
I agree that the bone structure in the limbs of these species makes them homologous traits, it was very common for people to find that one. I even found that one myself. However, just so you know, Humans also are classified as Chordates. This is because both fall into the Phylum Chordata. Where birds and humans differ is in their Classes. In this case a bird would fall into Aves, and humans would then fall into Mammalia,or mammals. I also thought your pictures were really good examples and further compared and contrasted the structures of the species of animals.
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