1.
The two species that I chose to represent homologous traits
are rabbits and lizards. Though their forelimbs might be different due to their
natural lifestyle, they both share a common set of bones, the radius, ulna, and
humerus.
Lizards are carnivores and their diet consists of insects,
eggs and other sources of meat. Rabbits are herbivore they mostly eat leafy plants and
vegetables.
The homologous trait of these two species is a set of common
bones such as the radius, ulna, and humerus that is located in their forelimbs.
The differences these two poses are that the lizard has a stronger oral region
compared to the rabbits. Another difference is that the skin of the lizard is
more scale like as compared to a rabbit is shaved its fur you would see that
the skin is softer.
The general ancestor of these two species is the
Euthenopteron fish. The Euthenopteron was an ocean-dwelling prehistoric fish
that represent an important stage between fish and early tetrapod. The skeletal
bone structure of this fish fins shows common traits that were found modern day
animals such as rabbits, lizards, and frogs.
2.
I chose the penguin and fish for analogy.
Penguins are large flightless seabirds that have wings
developed into flippers for swimming under water.
Fish are limbless cold-blooded vertebrate animals that have
gills and fins.
Both penguins and fish have fins to help them swim. They both
are predators; the penguin eats fish, shrimp, squid and the fish eats other
fishes or plankton. These two species are analogous trait due to convergent
evolution, since they had to adapt to their environment.
As for common ancestor between the fish and penguins I didn’t
find one. Their traits weren’t inherited
by common ancestors.
I agree that there are distinct differences between the limb structure of lizards and rabbits and that they are homologous traits. But you needed to focus on the limb structure, discuss those differences and explain why they are different. The discussion on the "oral region" and the skin" doesn't help your argument. Why are the limb structures different in rabbits and lizards? How do they function differently and why? That is where your discussion needed to go.
ReplyDeleteYou don't need to go back so far to find a common ancestor. Mammals arose from ancient reptiles. So did modern reptiles. So the common ancestor was an ancient reptile. And since that reptile possessed the ancestral limb structure, these two traits are homologous. However, your discussion on the fish ancestor seems to get the point of common descent.
I agree that the penguin and fish did not inherit their fins through common descent, but they do have a common ancestor of some ancient fish (mammals from reptiles from amphibians from fish). That means the modern fish did inherit the fin structure from this ancient ancestor. But we do know that the fins of the penguin are derived wing structures, unique to penguins and independently evolved, not from common descent. That is why these traits are analogous.
Good images.
This comment has been removed by the author.
ReplyDeleteYou did an excellent job on your post. Your explanations were clear and straight to the point. I loved the examples you used for both traits.
ReplyDeleteHello, Erick,
ReplyDeleteTo start off I want to say great blog post! It is interesting how a rabbit and a lizard share a common set of bones. Before this class I don’t think I would have never compared the two species. Also I loved the penguin and bearded dragon images! Aren’t penguins and bearded dragons the cutest!
Hi Erick,
ReplyDeleteI couldnt believe that the ancestor of the lizard and rabbit is a fish! I could see how it fits for the lizard but for the rabbit its hard to believe. That's really amazing. I really enjoyed your post. Great job!