a. A rabbit and frog may not seem closely connected but they can be linked together. One is a mammal and the other an amphibian.
b. The homologus trait that these two animals possess are forelimbs. Although they do not look exactly alike, they are relatively the same internally. However, they can serve different purposes for each animal. While both use a hopping technique to evade predators, rabbits use their forelimbs more for balancing while eating vegetation (not catching food) and frogs can use their forelimbs to shove food into their mouths or actually catch food. Each also have 5 'fingers', if you will, but serve different purposes. The rabbits 'fingers' have recessed while the frogs have grown to enhance swimming. Rabbits and frogs both have forelimbs, but evolved and adapted to their environments.
c. My research led me to the Eusthenopteron. The fish would have developed forelimbs in their fins which eventually led to them becoming a land creature. Evolution then took its course and each developed their own use for the forelimbs.
2. Analogous Traits
a. A fish and a whale are two different species. Fish have gills while whales are mammals and need breathe air because they have lungs.
b. A fish's fin and a whale's flipper serve the same purpose, to help the animal swim. They may look alike on the outside, but they do differ on the inside. A fish's fin is composed of a single bone while a whale's fin contains hidden 'fingers' inside. Again, these two different types of fins help serve the same function, which is to swim and maneuver in the water.
c. They do share a common ancestry. The fish would have gave rise to amphibians, which then gave rise to reptiles, which then birds and mammals split from. The same structure from the fish fin would have been carried throughout the evolution process. Whales, originally being land mammals, returned to the sea and then basically evolved fins on their own.
Sorry the pictures didn't come out so well!!!!
ReplyDeleteHi Daniel. I agree 100% with your research. The eusthenopteron was the ancestor for early land vertebrates, frogs and rabbits alike. I commend you using two creatures with such evolutionary distance. The fish and whale fins are definitely analogous structures, since the whale was once a land mammal. I recommend you try to upload your pictures directly, instead of link them.
ReplyDeleteHi Daniel, I did not realize whales were once land animals. That would also explain why human hands and whale fins are homologus traits! Watching species change over the centuries through environmental evolution makes you really wonder what you are exposing yourself to. 1000 years from now, how will the human race be like with all this UV exposure, radiation, pollution, etc? Regarding the pictures, if you save the pictures and then uploading them they should show up.
ReplyDeleteMr. Schulz,
ReplyDeleteI find that the common traits between rabbits and frogs are fascinating. I never would have thought that before reading this. It does make perfect sense that their forelimbs are in connection to one another because of how they both use them. Great post!
Good background work and description on your homologous traits. Do you really need to go all the way back to a fish (which doesn't possess the trait in question) for the common ancestor? Wouldn't the ancestral amphibian be far enough?
ReplyDeleteYou did a great job walking through the logic of ancestry with your analogous trait. Very well done. Clear and concise.
Images didn't come through. Refer to the help page on the class website if you need guidance on this.