Homologous and Analogous Traits
Homologous
traits
a) The
Lizard and human arm similar in nature in the fact that the lizard has the bone
structure of a human arm.
b
) At
the end of a human are there are 5 extensions which are called fingers. Also, at
the end of a lizard’s leg are also five extensions, which closely resemble that
of a human; the bone structure is the same. Each species have 6 bones on each
limb. However the lizard uses his limbs in order to crawl and move fast. A
human uses his limbs for other uses, such as opened doors, writing and dressing
himself.
c) I
would say generally speaking the ancestors of species named above would be the dinosaurs
and Neanderthals. The dinosaurs are the ancestors of lizards because of the
body structure and survival tactics. Additionally the Neanderthals are
ancestors of humans because again, of the same body structure, living
techniques and facial features.
Analogous
traits
a) Two
different analogous species would be a butterfly and a bird wing. Although they
are used for the same purpose, which is to fly they don’t immediately resemble
each other.
b) The
function for both as stated earlier would be to fly. However, the wing of a
butterfly is much smaller and more delicate than that of a bird wing. The limb
of a butterfly is without bony structure and the wing of a bird had bony
structure.
c) I
believe the common species of the butterfly and bird did posses analogous
structure. That is what helped them fly in the first place. And both species
have evolved from that.
Good job picking out what species to compare for your homologous and analogous traits. I like how creative you got comparing a mammal and a reptile and a bird with an insect. For the homologous trait is if cool to see that all forelimb species derived the trait from a common ancestor because there are so many forelimb species in existence. I like how you compared the skeletal structure of the forelimb of a human and a lizard showing how the bones are very much the same, yet their functions so different. The comparison between a birds ability to fly and a butterflies ability to fly is a good analogous trait as well because they both have the functional ability to fly, yet do not come from a common ancestor. Thanks for sharing. Nice post.
ReplyDeleteJacq~
Yes, great job with what you did! I find it so interesting to see how much we have in common with other species. It had never crossed my mind to compare myself with a lizard or even a whale. Your post was very interesting and allowed me to see how lizards have the same arm structure as we do.
ReplyDeleteThis was very knowledgable in the sense that I never thought about how humans and lizards have same bone structure. I definitely learned something new. The thing about 5 extensions was well detailed and I learned more new facts.
ReplyDeleteThis was a good, valid homologous trait with excellent descriptions. The only issue was the description of the common ancestor. There can only be one, technically, and it has to be at the point when the two organisms diverged in their ancestry. Neanderthals arose long after this divergence (which was during the time or reptiles), and they aren't actually an ancestor of modern humans, so they couldn't be a common ancestor. Dinosaurs were actually a specific type of reptile and not the common ancestor. The common ancestor was actually more likely to be one of the smaller reptiles running around the feet of the dinosaurs! All you needed to recognize was that common ancestor was likely a reptile who shares the homologous trait and passed it on to both lines of descent.
ReplyDeleteYour analogous trait was also very good, but remember that the key to the analogous trait is that the traits were NOT inherited from the common ancestor but arose independently through parallel evolution. So the ancestor may have had wings or may not have, but at least one of these organisms (definitely the bird) developed wings independently. In the bird's case it looks like during the time of it's rise from reptiles during the age of the dinosaurs.
I did my blog on the human arm and the whale fin that is closely related to this animal too! It is so cool that we are homologous to a reptile, to bad we are not as quick with our arms. Thats why the function is different though, in the end I am glad I am not a Lizard lol. The other blog i posted on also did a butter fly and bird, I guess no one can find the common ancestor. Oh well i think it would be interesting to see what it is. Overall a good blog, learned alot!!
ReplyDelete