Analogy and Homology Traits
1. Homologous traits
a.The two different species that share the homologous trait are the common bird and the arctic fox who has similar bones in their legs as a bird does in its wings.
b. The bones look quite similar, but the fox has them in its legs, while birds have them in their wings. Therefore the fox uses them to run, and a bird uses them to fly. Both are of a similar exertion, regardless of their placement, because it is what pushes each of them forward.
c. The fox shares a common ancestor with all organisms, but is more closely related to vertebrates like reptiles, amphibians and birds.
d.
d.
2. Analogous traits
a. The two different species that share the analogous trait are the domestic dog and the bear, who both have long snouts, or sometimes called, muzzles.
b. Bears and dogs both have the same long muzzle that look remarkably similar. These help them chew and tear up meat when eating. The long snout gives them a better sense of smell, which is crucial for hunting prey. In addition, for example, in polar bears the long snout helps warm the inhaled air.
c. Dogs and bears are both part of the Caniformia (Canoidea) suborder, which includes the "dog-like" carnivores (order Carnivora), like bears, dogs, etc. Caniforms first appeared as tree-climbing, superficially marten-like carnivores in the Eocene around 42 million years ago.
Bears and dogs are different enough to be granted their own separate families though, but do share a common ancestor along way back. There once was even an animal called a Bear Dog.
d.
Bears and dogs are different enough to be granted their own separate families though, but do share a common ancestor along way back. There once was even an animal called a Bear Dog.
d.
Alexandra,
ReplyDeleteI really enjoyed reading your post about the dogs and bears. Dogs are by far my favorite animal to talk about! Yes, I own 4 of them! :) I really liked how you found 2 pictures that look very similar and have the same color hair because it shows how similiar these two animals can be even though they're from different species. The snout is the most important part of a dog and bear because like you said, it is used to smell when hunting or even in danger. I feel honetly the only difference between bears and dogs is the fact that bears can climb trees and stand on their hind legs to make them look bigger when faced with a problem. By looking at these pictures obviously they look like they can be a similar species and have a recent ancestor, howeverm that is not the case. Yes all pairs of organisms share an ancestor, it just depends on how far back in time you are willing to research. I think that's so cool how there was an animal called a Bear dog, that is so interesting. Just by the name of it seems like a bear and a dog mated at some point in time, but who knows.
Hi Alexandra,
ReplyDeleteI would have never thought that a bird and an arctic fox have homologous traits in common, they don't have anything that looks alike, but i guess they use the same bone to move around one uses it in their legs and the other in their wings. thats an interesting one. Also the bear and the dogs look exactly alike i would have thought that they are the ones related I didn't know they use it to help them chew and help them eat i thought it was just the way their noses were shaped.
Hello Alexandra,
ReplyDeleteI just read your post and I found it very interesting that fox have similar bones that birds have in their legs I would have never guessed that. I also found it rare that fox’s actually are more related with vertebrates. I was wondering why that is I would imagine that they are more directly related with mammals? I was also surprised to find out that dogs and bears are actually not as closely related as I had thought they would be considering they look much alike.
I would like to point out another important difference in the bones of the fox and the bird. The bird bones are porous, smaller and much lighter to allow for flight with less energy burned. Tetrapods, such as the fox, have denser bones to help support body weight during the concussive force of each running stride. While you mention that differences exist, getting more specifics would have been a good thing to include here.
ReplyDeleteYes, the fox shares common ancestry with the birds, but how does that support your claim that these traits are homologous? How does it show that these traits share genetic ancestry?
Remember that analogs are traits that share common function due to similar environmental pressures, but not due to common ancestry. I see similarities between the two structures on the bear and the dog, but I also see that they are relatively close from a phylogenetic basis. What evidence do you have that these traits arose independently, through convergent evolution and not because the traits were inherited from a common ancestor?
Good images.
thank you
ReplyDelete