Login

Join for Free!
118498 members


on phylogeny / what are we ?

Discussion of everything related to the Theory of Evolution.

Moderator: BioTeam

Re: on phylogeny / what are we ?

Postby Crucible » Sun Oct 16, 2011 8:49 pm

How is it that we did not cease to be mammals, if splitting off caused loss of all previously existent relation to everything ?

How/why did we cease to be apes or monkeys but did not cease being mammals or vertebrates or tetrapods ?
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Postby aptitude » Sun Oct 16, 2011 9:33 pm

The groups of mammals, vertebrates, and tetrapods are monophyletic groups.

I'm now wondering: are you a creationist trying to somehow disprove human evolution with this "argument"?
aptitude
Coral
Coral
 
Posts: 115
Joined: Sat Sep 10, 2011 12:58 am

Re:

Postby Crucible » Sun Oct 16, 2011 10:18 pm

aptitude wrote:The groups of mammals, vertebrates, and tetrapods are monophyletic groups.

I'm now wondering: are you a creationist trying to somehow disprove human evolution with this "argument"?
So ? if not a monophyletic group, then automatically an ancestor is not an ancestor ?
That makes no sense.

BTW You don't have to worry about my motive, you need to worry about what you believe, as it isn't hanging together .
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am


Postby aptitude » Mon Oct 17, 2011 12:03 am

As I said before, the whole question is about terminology and definitions, not about concepts. That being said, what we are arguing about does not have to do with whether or not humans evolved from apes, it only has to do with the officially accepted definition of a couple of biological terms.

According to the *definition* of ape, it is paraphyletic, and according to the *definition* of paraphyly, the most recent common ancestor of humans and apes is considered part of the group of apes, and humans are not considered apes. The fact that humans are not considered apes does not somehow seclude Homo sapiens from the apes, nor does it prove that we have not evolved from our ancestor. It is simply a matter of terminology and semantics.

On the other hand, the mammals form a clade that includes the primates, and thus by *definition*, humans must be mammals.
aptitude
Coral
Coral
 
Posts: 115
Joined: Sat Sep 10, 2011 12:58 am

Re: on phylogeny / what are we ?

Postby Crucible » Mon Oct 17, 2011 12:09 am

But you seem to switch from accepting a term and rejecting it, back to accepting it... depending on what you are trying to prove.

You said
Yes, I believe this ancestor would still be classified as an Old World Monkey (an ape).


but you also said...

No, because apes is not a clade (monophyletic group)

and
So by definition, our most recent common ancestor would be considered an ape, but we Homo sapiens, plus all the other "transitional species", would not.



Why does being transitional make any difference ?

You're saying, are you not, that the first tiny tiny difference in that Ape, from it's norm for the species ( which was an ape), made it suddenly become not only a different species, but suddenly...lost it's ancestry, and became "non ape" ?
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Re: on phylogeny / what are we ?

Postby aptitude » Mon Oct 17, 2011 12:51 am

Crucible wrote:But you seem to switch from accepting a term and rejecting it, back to accepting it... depending on what you are trying to prove.

You said
Yes, I believe this ancestor would still be classified as an Old World Monkey (an ape).


but you also said...

No, because apes is not a clade (monophyletic group)

Stop quoting me out of context. I said the ancestor is an ape, but we are not.

Crucible wrote:and
So by definition, our most recent common ancestor would be considered an ape, but we Homo sapiens, plus all the other "transitional species", would not.



Why does being transitional make any difference ?

You're saying, are you not, that the first tiny tiny difference in that Ape, from it's norm for the species ( which was an ape), made it suddenly become not only a different species, but suddenly...lost it's ancestry, and became "non ape" ?

Haven't I already explained this about 3 times already? It's the definition of an ape.
aptitude
Coral
Coral
 
Posts: 115
Joined: Sat Sep 10, 2011 12:58 am

Re: on phylogeny / what are we ?

Postby Crucible » Mon Oct 17, 2011 1:13 am

aptitude wrote:
Crucible wrote:But you seem to switch from accepting a term and rejecting it, back to accepting it... depending on what you are trying to prove.

You said
Yes, I believe this ancestor would still be classified as an Old World Monkey (an ape).


but you also said...

No, because apes is not a clade (monophyletic group)

Stop quoting me out of context. I said the ancestor is an ape, but we are not.
Why should I include more context when it's unnecessary to include more ? Show what more added that I excluded, would have put it in a different light. I'm showing that you used the terms which you reject when discussing ancestry on the grounds that such and such a grouping is not monophyletic. That is analogous to saying that because I have five siblings, our parents are not the parents.



Crucible wrote:and
So by definition, our most recent common ancestor would be considered an ape, but we Homo sapiens, plus all the other "transitional species", would not.



Why does being transitional make any difference ?

You're saying, are you not, that the first tiny tiny difference in that Ape, from it's norm for the species ( which was an ape), made it suddenly become not only a different species, but suddenly...lost it's ancestry, and became "non ape" ?

Haven't I already explained this about 3 times already? It's the definition of an ape.


No, you've only switched back and forth between rejecting terms and using them to make a point.

You're using a Linnaean approach to deny a monophyletic approach and the reverse
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Re: on phylogeny / what are we ?

Postby Crucible » Mon Oct 17, 2011 1:17 am

It's the definition of an ape.
If I understand this statement, it means that you are defining the reality of ancestry away.

that is, are you not saying that a common ancestor of some members of a non monophyletic group, is not the ancestor, because it's a non monophyletic group ?
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Re: on phylogeny / what are we ?

Postby Crucible » Mon Oct 17, 2011 1:34 am

What would Proconsul kinds of animal be called ?
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Re: on phylogeny / what are we ?

Postby biohazard » Mon Oct 17, 2011 6:41 am

Crucible wrote:How is it that we did not cease to be mammals, if splitting off caused loss of all previously existent relation to everything ?

How/why did we cease to be apes or monkeys but did not cease being mammals or vertebrates or tetrapods ?


Those are simply man-made categories. We would be apes if we just decided to call us that...

Sure, counting the number of legs or checking for the existence of spine are both quite neat categories, but it comes more obscure when the differences get smaller. I do not think there is really anything that would make us not apes, except the fact that many people freak out badly if they realize just how closely we are related to other apes.
User avatar
biohazard
King Cobra
King Cobra
 
Posts: 776
Joined: Sun Apr 08, 2007 6:45 pm

Re: on phylogeny / what are we ?

Postby Crucible » Mon Oct 17, 2011 7:11 am

biohazard wrote:
Crucible wrote:How is it that we did not cease to be mammals, if splitting off caused loss of all previously existent relation to everything ?

How/why did we cease to be apes or monkeys but did not cease being mammals or vertebrates or tetrapods ?


Those are simply man-made categories.
Yes, they are. Anything we could say, is man-made.


We would be apes if we just decided to call us that...

Sure, counting the number of legs or checking for the existence of spine are both quite neat categories, but it comes more obscure when the differences get smaller. I do not think there is really anything that would make us not apes, except the fact that many people freak out badly if they realize just how closely we are related to other apes.
Wouldn't it give a different rhetorical spin, were the genus Homo to be thought of as grouped along with genus Pan, in the tribe Panini - or something less bakery product-sounding.
Crucible
Coral
Coral
 
Posts: 187
Joined: Sat Sep 24, 2011 3:46 am

Re: on phylogeny / what are we ?

Postby biohazard » Mon Oct 17, 2011 8:26 am

Crucible wrote:Wouldn't it give a different rhetorical spin, were the genus Homo to be thought of as grouped along with genus Pan, in the tribe Panini - or something less bakery product-sounding.


Beats me.

I have a feeling that there are sects of people who loathe to categorize us humans with any other group, because that would make us look like *gasp* animals, and [sarcasm] most certainly we are something much more grand and beautiful and fancy than those lowly animals are [/sarcasm]
User avatar
biohazard
King Cobra
King Cobra
 
Posts: 776
Joined: Sun Apr 08, 2007 6:45 pm

PreviousNext

Return to Evolution

Who is online

Users browsing this forum: No registered users and 1 guest