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Author Topic:   Definition of Species
Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 143 of 450 (570886)
07-29-2010 10:27 AM
Reply to: Message 142 by Big_Al35
07-29-2010 10:18 AM


Re: Not even tangential to the original direction.
Big_Al35 writes:

We know that some modern fish have X,Y,Z. These will have mated with fish which don't have X,Y,Z. (As in B or C's mate.)


So? You said there were modern fish with X, Y and Z, (the descendants of B) and also that all rabits had X, Y and Z (The descendants of C). This means that if they have a common ancestor, which they do, it should also have genes X, Y and Z. in your example this would be A and in your example it has those genes.

Most common ancestors therefore are unlikely to have X,Y,Z. We cannot therefore use X,Y,Z to determine lineage.

Of course we can, the common ancestor should have those genes. And in your example (A) was the common ancestor and has those genes. Or have you forgotten your own example?

Hence you can't apply this to rabbits.

In your example you clearly can.

This message is a reply to:
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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 155 of 450 (572281)
08-05-2010 7:04 AM
Reply to: Message 154 by Big_Al35
08-05-2010 6:51 AM


Re: Species Definition
Big_Al35 writes:

eg..if we found a fossil and then declared it a missing link between the bears and cats


There is no missing link between bears and cats. They share a common ancestor though.

and then further established it as a new species this would be absurd.

Well, if it isn't around today, it sure as hell is a different species, wouldn't you say?

We simply don't have enough data.

If it's not around today, it's a different species. What more data do you need?

Edited by Huntard, : typos


This message is a reply to:
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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 158 of 450 (572302)
08-05-2010 8:48 AM
Reply to: Message 157 by Big_Al35
08-05-2010 8:34 AM


Re: Species Definition
Big_Al35 writes:

The best we can do is to identify living species and the known extinct species (like the dodo).


The "known extinct species" include every fossil ever found.

Fossils that don't fall into the known categories/species would need another system.

Well, so far, there aren't any. And why would they require a new system anyway? Why not use the current one we used for all the "extinct species"?

But we can't just make up ad hoc species and lump these fossils under that category.

Why not?

We don't have access to the DNA, we don't know their behaviour and we can never know if they could interbreed. It has become an exercise in futility.

That's the problem with life. Everything is related to everything else. "Species" serve merely as an easy box to put everything in for us humans.

Paleontologists must discuss extinct organisms using some new criterion but they should never evangelise this new methodology to the proletariat as their new system has no basis in fact.

But why? What is wrong with the current system, that you advocate using on "all known extinct species", which include all fosills?

This message is a reply to:
 Message 157 by Big_Al35, posted 08-05-2010 8:34 AM Big_Al35 has responded

Replies to this message:
 Message 160 by Big_Al35, posted 08-05-2010 9:12 AM Huntard has responded

  
Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 161 of 450 (572316)
08-05-2010 9:16 AM
Reply to: Message 160 by Big_Al35
08-05-2010 9:12 AM


Re: Species Definition
Big_Al35 writes:

I see a huge difference between the dodo and the TRex in terms of our knowledge of the creatures. The dodo was known to man. TRex never was. I think we even have stuffed dodos in museums. Also the behaviour of dodos has been documented extensively. We can safely say that that was a species.


We can also safely say that T. Rex was a species.

TRex is a mystery. All we have are movie images and directors imaginations to go on. If you found two TRex half skeletons I think you would be hard pushed to even show that it was the same animal.

I would be, the experts, not really, no. With half a skeleton I predict a 100% sure identification.

You would have no idea if they could interbreed and their behaviour is unknown.

So? Also, there is quite a lot known about the behaviour of T. Rex.

Edited by Huntard, : added a bit


This message is a reply to:
 Message 160 by Big_Al35, posted 08-05-2010 9:12 AM Big_Al35 has responded

Replies to this message:
 Message 162 by Big_Al35, posted 08-05-2010 9:32 AM Huntard has responded
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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 163 of 450 (572322)
08-05-2010 9:37 AM
Reply to: Message 162 by Big_Al35
08-05-2010 9:32 AM


Re: Species Definition
Big_Al35 writes:

Again I must refer you to a link that I already supplied in another debate about the differences between lions and tigers.


Why? We're not talking about lions and tigers.

Ok here is one link from potentially many that supports my claim that the differences are hard to distinguish.

That says nothing about T. Rexes, and Wounded King supplied two (if I recall correctly, but at least one) link that showed that there are several very different things about lions and tigers.

I think you will agree that lions and tigers are different species, yet they have almost identical skeletons.

Yes, almost identical, but enough to distinguish the two. What this has to do with T. Rex identification however, is beyond me.

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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 193 of 450 (572520)
08-06-2010 9:43 AM
Reply to: Message 192 by Big_Al35
08-06-2010 9:37 AM


Re: Species Definition vs what matters (and why)
Big_Al35 writes:

If the DNA barcoding was defined such that two African elephants ended up being different species I think we can rest assured that our system needs adjusting.


But how would you determine that with DNA? It's not like there's gonna be a clear point at which you can say: "Aha! if it has these genes, it must be a different species!". That is arbitrarily determined by men, if it is determined at all.

Now if our system showed that African elephants were a different species to an Asian elephant then that would be a matter for debate

Why? Since they are already accepted as different species.

If you are saying that experts in the field are actively advocating that Ugandan elephants are distinguished from Zambian elephants and they want them classified as different species I don't have any objection with that as such. Once the system is established and in place we can stick with it.

But we already have a system in place, why change it?

This message is a reply to:
 Message 192 by Big_Al35, posted 08-06-2010 9:37 AM Big_Al35 has responded

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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 198 of 450 (572535)
08-06-2010 11:28 AM
Reply to: Message 196 by Big_Al35
08-06-2010 11:21 AM


Re: Species Definition vs what matters (and why)
Big_Al35 writes:

It's true we don't know much about TRex. 5 minutes on google will tell you that.


Ten seconds on Google Scholar brought up 22.800 articles. Don't know much indeed.

If species boundaries are arbitrary they are arbitrary....what misconstrual?

You tried to pass it off as if DNA would make an end to the arbitrary nature of species boundaries.

This message is a reply to:
 Message 196 by Big_Al35, posted 08-06-2010 11:21 AM Big_Al35 has responded

Replies to this message:
 Message 200 by Big_Al35, posted 08-06-2010 4:43 PM Huntard has responded

  
Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 201 of 450 (572587)
08-06-2010 4:55 PM
Reply to: Message 200 by Big_Al35
08-06-2010 4:43 PM


Re: Species Definition vs what matters (and why)
Big_Al35 writes:

Yeah...and they all contradict each other.


No they don't, which you would know, if you had read but a single one of them.

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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 213 of 450 (574494)
08-16-2010 8:45 AM
Reply to: Message 212 by Big_Al35
08-16-2010 8:28 AM


Re: Pushing back the boundaries of ignorance.
Big_Al35 writes:

How can the variable nature of the environment affect some parts of the DNA but not the important information storing parts which spell out that we should have arms, legs, torso, head etc.


It does effect that.

I am guessing you are going to tell me now that some people are born with three legs?

Well, there is this person:

But then again, examples abound in nature of six legged sheep and all other sorts of "deformed" creatures.


This message is a reply to:
 Message 212 by Big_Al35, posted 08-16-2010 8:28 AM Big_Al35 has responded

Replies to this message:
 Message 216 by Big_Al35, posted 08-16-2010 9:08 AM Huntard has not yet responded
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Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


(1)
Message 441 of 450 (653378)
02-20-2012 1:18 PM
Reply to: Message 440 by Big_Al35
02-20-2012 1:01 PM


Re: Hyperspeciation?
Big_Al35 writes:

Robert claims that he sees diversity of species today. Eye witness accounts still constitute evidence (especially in court) from what I understand. Furthermore, Robert refers to the bible, an ancient text which must have had an author. This also is valid evidence (even if you disagree with its contents). Robert has therefore supplied his evidence but Taq isn't offering any evidence to counter Robert's claims.


I claim that I see diversity of species today. Eye witness accounts still constitute evidence (especially in court) from what I understand. Furthermore, I refer to "On The Origin Of Species", a text which must have had an author. This also is valid evidence (even if you disagree with its contents). I have therefore supplied evidence to counter Robert's claims.

Edited by Huntard, : spellings


This message is a reply to:
 Message 440 by Big_Al35, posted 02-20-2012 1:01 PM Big_Al35 has responded

Replies to this message:
 Message 443 by Big_Al35, posted 02-20-2012 3:49 PM Huntard has responded

  
Huntard
Member (Idle past 606 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


(2)
Message 446 of 450 (653405)
02-20-2012 5:34 PM
Reply to: Message 443 by Big_Al35
02-20-2012 3:49 PM


Re: Hyperspeciation?
Big_Al35 writes:

Ok, so Robert has supplied evidence and Huntard has countered with evidence too.


Hate to burst your bubble, but neither Robert nor I posted anything coming even remotely close to what would be considered evidence. I had hoped that my silly little attempt at sarcasm would make that clear, but apparently it hasn't. My apologies to you for not telling you in a clear and easy to understand fashion.

This message is a reply to:
 Message 443 by Big_Al35, posted 02-20-2012 3:49 PM Big_Al35 has responded

Replies to this message:
 Message 447 by Big_Al35, posted 02-21-2012 7:22 AM Huntard has not yet responded

  
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