Both animals possess 4 toes on each foot and are part of a group of animals called "even toed ungulates" meaning they have an even number of toes (2, 4, 6...) Camels are also members of this animal group. The difference between a Pig's foot and a Hippo's foot is that, the Hippo's foot is webbed in order to allow it to move around the water with ease. While the Pigs's foot is not, allowing it to dig for food sources (roots, worms, bugs, etc.) and traverse dry land. The structural differences in their feet are present due to the type of terrain these animals spend most of their time in.
The only similarity between these 2 animals is the fact that they are both Artiodactyls (or animals with hoofed feet) which proves common ancestry.
(Other than the classification of the 2 I cannot find any information on what animal the common ancestor is)
For more information regarding Artiodactyls visit:
http://animaldiversity.ummz.umich.edu/accounts/Artiodactyla/
I have decided to choose Seals and Sharks. Seals (along with Sea Lions and ALL of their cousins) are Aquatic Mammals that spend a majority of their lifetime in the water only spending time on land to mate, sleep and birth their young. While Sharks are members of the fish world they live their entire life in the water without any exceptions.
The analogous trait between these two animals is their fins located on the sides of their bodies (where the arms would be). The similarities between their fins are location along the body and their function. These animals' fins allow them to navigate through the water with minimal resistance. The differences between the two are their range of motion, a seals fins operate more like a birds wings do helping it propel itself through the water, while the sharks fins have minimal mobility more like the flaps on the wing of an airplane, affecting their trajectory and not their speed.
I am not sure how a common ancestry is possible with the 2 animals being from different animal families (Fish vs. Mammals). But I can say that if they did have a common ancestor it would have lived in the water, and yes it would have possessed this trait.
Very informative post Evan. I learned something new tonight about the pig and hippopotamus!
ReplyDeleteI came to a similar conclusion as your analogous section (part c). A common ancestor is not really known or does not exist yet the physical similarity is so large..
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ReplyDeleteInteresting homologous comparison! Good detail and well-explained.
ReplyDeleteWith regard to ancestry, there is no doubt that they are not too far apart genetically (relatively speaking) but it would be interesting to know, since they are in a group with two and four-toed organisms, if they evolved their four-toes independently or inherited that trait from their common ancestor. The homolog is the basic foot structure, with the differences being the presences or absence of webbing. Just wondering if we may also be looking at a pair of analogous traits in the evolution of four toes or if that was inherited from the common ancestor as well. The link below, given how early pigs broke off from the pack, suggests that four toes perhaps evolved independently.
http://www.thomsonsafaris.com/blog/whale-and-hippo-dna/
Good description and explanation of your analogous pairing.
All organisms have a common ancestor if you go back far enough, and you are correct to surmise that this common ancestor was aquatic. Sharks are one of the oldest living creatures on the earth... they are essentially a swimming fossil. They haven't changed all that much, physically, over hundreds of millions of years and they inherited their body shape from that early common cartilagenous fish ancestor. The seal took a different route from that ancestor, through boney fish, to amphibians (where they lost that body shape), to reptiles, and finally to mammals. Seals and other aquatic mammals evolved from land mammals, re-evolving that shark-like body shape that works so well in the water through convergent evolution. Because we know that seals evolved this body shape independently from the common ancestor with the shark, we know that these traits are analogous.
Other than the clarification on ancestry issues, good post.
Interesting comparisons! It was a little challenging for me to find your actual responses with the questions in your post as well, but the responses that were there were well done. Something that would be cool to know is how big this family of even toed creatures is and if they all do have some relationship. Good post.
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