Michelle Vasquez
Anthropology 101
11/08/12
- a. Two species that posses the homologous trait are dogs and whales.
b. The homologous trait that the
dog and whale posses are the bones in their flipper/feet. Both the flipper and
feet have similar bone structures and even have the same bones (phalanges.)
However, dogs and whales use this trait extremely differently. Dogs use their
feet to walk, run, dig, etc. Whales use their flippers to swim in their water
home. Although they share similar bones and bone structure they both use them
for entirely different things and do not even live in the same habitat.
c. The common ancestor of the dog
and whale is known as the mesonychidae. This
animal walked on land and had the similar bones and bone structure that the dog
and whale posses today. Some of the ancestors of the mesonychidae branched off
to go live in the water while others stayed on land. The ones in the water
eventually evolved into whales and the ones on land evolved into dogs.
d.
Dogs:
Whales: 
- a. Two species that posses the analogous trait are sharks and dolphins.
b. The analogous trait these
species share are their body shapes, fins, and flippers. These traits show
similarities because both species have the same body shape that helps them swim
through the water. Their fins and flippers also aid them in swimming and being
able to move around. Even though they are from two completely different
species, they have similar traits that help them move around in the water.
c. No, the dolphin and the shark do
have a common ancestor that posses this analogous trait. Shark ancestors have
been hard to find because they have cartilage so their bones do not fossilize.
Sharks have pretty much looked the same throughout time. Dolphin’s ancestors
actually walked on land and gradually moved to the water.
d. Shark: 
Dolphin: 
Hi michelle I think you did a very good job talking about how the dog and a whale have some of the same homologous traits that arrived from a common ancestor many years ago. It is interesting to see how dogs and whales have used these traits completly different since dogs walk on land and whales swim in the ocean. I also liked your point on the analogous traits between a dolphin and a whale which came from a common ancestor that did not have fins or tail called myllokunmingia the oldest fish fossile.
ReplyDeleteThere fins do help them to move in the water and have many similar traits to each other. Both of there bodies are very similar in shape.
Great job describing the Homologous and analogous traits in all the species. You did a very good job on really getting into detail. I liked how you described the dog and whale, i had no idea they had a common ancestor. Great Job!
ReplyDeleteGood homologous comparisons. I'm not sure if we can actually get that specific on the common ancestor but as long as you understand that the common ancestor was a mammal who possessed the basic limb structure inherited by both organisms, you are in good shape.
ReplyDeleteWith regard to your analogous trait, actually the common ancestor did possess this streamlined shape since the common ancestor was an early fish, and the shark likely inherited it directly. However, the dolphin developed the trait independently as a mammal, which means these are still analogous traits.
I loved your post I thought it was really insightful. I even read it to my kids. I had no idea that there were any similarities between dogs and whales, so that was very interesting to learn. I was a little confused as to what the analogous trait was exactly. Was it just the structure of the body in general or was it something specific?
ReplyDeleteAlexzandrea,
ReplyDeleteI'm glad you enjoyed my post. From my understanding, an analogous trait could be the structure of the body, specific bones or bone structure they shared, or anything else that two animals share but are from two different species. For instance, the dolphin and shark share similiar body structure but one is a mammal and the other is a fish. They independently acquired these traits because they both happen to live in the water.