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Author Topic:   Does microevolution logically include macroevolution?
AdminNosy
Administrator
Posts: 4754
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 181 of 195 (250585)
10-10-2005 9:27 PM
Reply to: Message 180 by Springer
10-10-2005 9:22 PM


Support for you assertions
Furthermore, macroevolution is, as far as is known, biologically impossible.

You will have to support this claim; in detail.

It will require a defintion of macroevolution (and not just an example, especially a silly one that looks at extreme endpoints). It will then require the detailed evidence and reasoning showing support for your assertion.

This statement and pretty well all your other posts demonstrates to me that you don't belong in the science based side of the site.

You have this opportunity to show that I am wrong. If you don't start makeing better attempts at supporting you claims you will start with a 24 hour suspension from the science side very soon now. That will lengthen as required.


This message is a reply to:
 Message 180 by Springer, posted 10-10-2005 9:22 PM Springer has not yet responded

  
New Cat's Eye
Inactive Member


Message 182 of 195 (250864)
10-11-2005 4:21 PM
Reply to: Message 180 by Springer
10-10-2005 9:22 PM


Re: macroevolution is presumed, not proven
:rolleyes:

I'd reply to you if I thought you'd reply back, but judging from every one of your posts awaiting replies, I'll take this time to remove one more 'yes' from my list.


This message is a reply to:
 Message 180 by Springer, posted 10-10-2005 9:22 PM Springer has not yet responded

  
crashfrog
Inactive Member


Message 183 of 195 (250950)
10-11-2005 7:13 PM
Reply to: Message 180 by Springer
10-10-2005 9:22 PM


Re: macroevolution is presumed, not proven
Note to self - don't feed the trolls.

This message has been edited by crashfrog, 10-11-2005 07:16 PM


This message is a reply to:
 Message 180 by Springer, posted 10-10-2005 9:22 PM Springer has not yet responded

  
Tony650
Member (Idle past 2197 days)
Posts: 450
From: Australia
Joined: 01-30-2004


Message 184 of 195 (254771)
10-25-2005 4:39 PM
Reply to: Message 178 by Nuggin
10-07-2005 6:00 PM


Re: Pushing the Dog Boundry
Thanks for the replies, guys.

Nuggin, thanks for the link.

Nuggin writes:

Don't forget the Bush Dog - a rare breed found in the jungles of S. America
http://www.canids.org/SPPACCTS/speothos.htm

That's really a dog? Cool! Speothos venaticus... So, it's further removed from the domestic dog than wolves and coyotes, but still within the family Canidae. Well, if you hadn't told me, I would have thought it was some odd kind of bear.


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 Message 178 by Nuggin, posted 10-07-2005 6:00 PM Nuggin has not yet responded

  
Tony650
Member (Idle past 2197 days)
Posts: 450
From: Australia
Joined: 01-30-2004


Message 185 of 195 (254775)
10-25-2005 4:56 PM
Reply to: Message 179 by New Cat's Eye
10-07-2005 6:57 PM


Catholic Scientist writes:

I would say that with our current usage of 'species', some dog breeds could be considered different species.

I would think so, too. Though I must admit that I'm not completely clear on exactly what our current usage of "species" is. It seems to me that there has to be more to it than simple morphological differences. There are both organisms which appear very similar yet are different species, and organisms which appear very different yet are the same species. This leads me to wonder exactly how they are classified in the first place. Genetically, perhaps? Is it simple reverse chronology (lineage A split from lineage B... which, further back, split from lineage C... etc)?

Catholic Scientist writes:

I don't know but I would like to know.

Indeed. I'd really like to hear from someone in the pertinent fields about this. Can anyone tell me if this is true? Is there actually a larger genetic gap between examples like German Shepherds and Wolves than German Shepherds and Pekingese, despite their respective morphological similarities/differences?

Catholic Scientist writes:

Aren't there some ring species that could interbreed, genetically, but don't because of morpholigical differences? If they are considered different species not because they can't interbreed but because the don't interbreed, the same could be said of some species breeds of dogs.

So, mere physical incompatibility (despite genetic compatibility) is sufficient, in some cases, to warrant classification as separate species? Perhaps, in the instance of the domestic dog, it is simply a case of convenience, then? Technically, they would qualify as multiple species, but, due to their consistent, close association with man during the centuries (millennia?) of their domestic breeding, we have simply never bothered to class them any differently.

Catholic Scientist writes:

But just to muck up the distinctions some more... A dog and a wolf can, and will, interbreed to produce viable offspring.

Yes, so I've heard. I assume that, in this context, the word "dog" would refer to one that is not so far removed, morphologically, from the wolf... like the German Shepherd I mentioned previously, for example? Somehow, I have a hard time picturing a wolf getting it on with a Yorkshire Terrier.:laugh:

Catholic Scientist writes:

I don't think that a great dane and a chihuahua would ever reproduce, naturally.

No, probably not naturally (by which I assume you mean "via regular mating, without the intervention of man"). But what I was really wondering was whether or not they are too genetically different to reproduce... hence my question regarding artificial insemination. That is, would their genes be compatible enough to produce viable offspring, in principle, even if the parents could never produce them on their own, due to morphological differences?

In any case, if, as you say, the physical impracticality of mating between two nonetheless genetically compatible organisms is enough to classify them as separate species then I suppose the question of whether or not it could be done artificially is moot. Still, I am curious to know. I'd love to hear from any of the resident biologists/geneticists on this. Or just anyone who is familiar with the fields and can answer, really.:)

Catholic Scientist writes:

So where do you draw the line? Do you redefine the word species just because the dogs screwed it up?

No, that's not what I was getting at. To be honest, I'm at a loss as to what the definition of "species" is, and I was just wondering how the plethora of domestic dog breeds fit into it. Just to be clear, I don't think that dogs screwed anything up; I think that we screwed up by continuing to class them all as the same species when it would seem, from what I've read, that they have diverged sufficiently enough to be classed separately.

I am, of course, still speaking from a position of ignorance, though. I'm careful not to make too many conclusions here because it is still unclear to me exactly what a species is supposed to be.


This message is a reply to:
 Message 179 by New Cat's Eye, posted 10-07-2005 6:57 PM New Cat's Eye has not yet responded

  
Parasomnium
Member (Idle past 861 days)
Posts: 2191
Joined: 07-15-2003


Message 186 of 195 (254780)
10-25-2005 5:18 PM


Dogs
Catholic Scientist and Tony650,

Has either of you seen this tread, and more specifically this and this post?

This message has been edited by Parasomnium, 25-Oct-2005 10:18 PM


"We are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further." - Richard Dawkins
  
SuperNintendo Chalmers
Member (Idle past 3999 days)
Posts: 772
From: Bartlett, IL, USA
Joined: 12-27-2005


Message 187 of 195 (273860)
12-29-2005 1:26 PM
Reply to: Message 149 by Springer
09-29-2005 1:57 PM


Re: What evidence do you expect?
I want to see someone try to breed a bat from a rodent. Do all the selective breeding you wish, and induce as many mutations as you want. I want to see one shred of evidence that you can bring the species one iota of a degree closer to a bat than it is now. The evolutinist rebuttal is simply, I don't have enough time. So, given enough time, you could do it. Where's the evidence?

You have a fundamental misunderstanding of the process. Species are human classifications of different population groups as they change over time. However, species DO NOT turn into other species. It just doesn't happen! Population groups change over time. If we look back and take a snapshot every million years or so we may see large differences between various temporal snapshots of the population group. However, the population group is ALWAYS the same speicies...

In fact, for all we know a present day dog would not be able to breed with a dog that lived 25,000 years ago.


This message is a reply to:
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Replies to this message:
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pianoprincess*
Inactive Member


Message 188 of 195 (282054)
01-27-2006 8:44 PM
Reply to: Message 187 by SuperNintendo Chalmers
12-29-2005 1:26 PM


Re: What evidence do you expect?
In fact, for all we know a present day dog would not be able to breed with a dog that lived 25,000 years ago.

but we have no evidence of that.


This message is a reply to:
 Message 187 by SuperNintendo Chalmers, posted 12-29-2005 1:26 PM SuperNintendo Chalmers has not yet responded

Replies to this message:
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crashfrog
Inactive Member


Message 189 of 195 (282134)
01-28-2006 10:24 AM
Reply to: Message 188 by pianoprincess*
01-27-2006 8:44 PM


Re: What evidence do you expect?
but we have no evidence of that.

We have a considerable amount of evidence, consisting of the observation that all living things have genetics, and all genetics work pretty much the same way. Also we observe that, no matter what the organism, significant genetic changes always occur in a population over as many generations as would be represented by 25,000 years in dogs. And we know that the genetics of two organisms have to be similiar in certain ways if they're to interbreed.


This message is a reply to:
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Replies to this message:
 Message 190 by NosyNed, posted 01-28-2006 10:55 AM crashfrog has responded

  
NosyNed
Member
Posts: 8842
From: Canada
Joined: 04-04-2003


Message 190 of 195 (282135)
01-28-2006 10:55 AM
Reply to: Message 189 by crashfrog
01-28-2006 10:24 AM


Dog Interbreeding
I think it is likely that you are wrong on the dogs in this case Crash. The way to make a better judgement of it would be to look at species that have been separated for a bit more than 25,000 years and see if they can still interbreed and to what extent.

I think, for example, that tigers and lions have been separated for far, far longer (guessing I would say for between 10 and 100 times longer) but there is still some residual ability to interbreed.

My guess is that if we looked at a few such examples we would expect that in a great number of cases mammals separated by only 25,000 years would still be able to interbreed perhaps enough to be called the same species.


This message is a reply to:
 Message 189 by crashfrog, posted 01-28-2006 10:24 AM crashfrog has responded

Replies to this message:
 Message 191 by crashfrog, posted 01-28-2006 12:44 PM NosyNed has responded
 Message 193 by Coragyps, posted 01-28-2006 4:41 PM NosyNed has not yet responded

  
crashfrog
Inactive Member


Message 191 of 195 (282143)
01-28-2006 12:44 PM
Reply to: Message 190 by NosyNed
01-28-2006 10:55 AM


Re: Dog Interbreeding
I think it is likely that you are wrong on the dogs in this case Crash.

I don't know for sure. But dogs are a special case; they've been subject to a considerably greater degree of selection than your tigers and lions during the last thousand generations or so.

Who knows? 25,000 years of dogs is 10,000 generations (give or take.) That's a considerable degree of genetic change right there. The same amount of time is a lot few generations for tigers and lions, who live much longer before reproductive maturity.


This message is a reply to:
 Message 190 by NosyNed, posted 01-28-2006 10:55 AM NosyNed has responded

Replies to this message:
 Message 192 by NosyNed, posted 01-28-2006 1:49 PM crashfrog has not yet responded

  
NosyNed
Member
Posts: 8842
From: Canada
Joined: 04-04-2003


Message 192 of 195 (282164)
01-28-2006 1:49 PM
Reply to: Message 191 by crashfrog
01-28-2006 12:44 PM


Re: Dog Interbreeding
I was giving T's and L's as only one example that I think I can be safe in saying have been separated by a LOT more than 25,000 years and a lot more than 10,000 generations.

Since there are, as you point out, a lot of things which can affect the outcome we'd have to look at a bunch of cases. We know that a single generation can be enough to draw a firm line even though that is rare. We have even had discussions about human chimp interbreeding (which might be just barely successful based on what we do know) which are separated by perhaps 500,000 generations.

All of this is guessing on my part. But you were guessing about dogs too. I'm just giving reasons why I would not be inclinded to accept your assertion too quickly.


This message is a reply to:
 Message 191 by crashfrog, posted 01-28-2006 12:44 PM crashfrog has not yet responded

  
Coragyps
Member
Posts: 5389
From: Snyder, Texas, USA
Joined: 11-12-2002
Member Rating: 4.0


Message 193 of 195 (282206)
01-28-2006 4:41 PM
Reply to: Message 190 by NosyNed
01-28-2006 10:55 AM


Re: Dog Interbreeding
New stuff on lion/tiger and cat-in-general divergences is hot off the press in Science 6 January 2006: Vol. 311. no. 5757, pp. 73 - 77. They have lions and tigers splitting about 3.7 million years ago, based on genetic markers of several sorts. So your "100 times longer" may be a bit of an underestimation. The paper is about the entire Family Felidae, which originated about 11 million years ago by their estimate. It would be most interesting to see about some other possible crosses in that family: I'd never heard of a kodkod, but I'll bet a kodkod X ocelot would be mighty purty!
This message is a reply to:
 Message 190 by NosyNed, posted 01-28-2006 10:55 AM NosyNed has not yet responded

    
ohnhai
Member (Idle past 3327 days)
Posts: 649
From: Melbourne, Australia
Joined: 11-17-2004


Message 194 of 195 (282263)
01-28-2006 11:01 PM
Reply to: Message 35 by tjsrex
08-30-2005 11:30 PM


...ts not going to make the fin as complex as a leg....

what makes you think a fin or the like isnt as complicated as a [human] leg? take the wing of a skate or manta for example... many many more bones than a human leg and far more muscles and thus control systems. You would be better to ask how do you reduce the complexity of a fin to get a leg?


This message is a reply to:
 Message 35 by tjsrex, posted 08-30-2005 11:30 PM tjsrex has not yet responded

    
ohnhai
Member (Idle past 3327 days)
Posts: 649
From: Melbourne, Australia
Joined: 11-17-2004


Message 195 of 195 (282265)
01-28-2006 11:48 PM
Reply to: Message 48 by tjsrex
08-31-2005 9:28 AM


Macroevolution needs new genes (for making feathers on reptiles, for example)

no it don’t.. it just needs accumulated change in existing genes to change them from ones that make scales to ones that make feathers.

you constantly seems to think along the lines that boom a new gene was added an in the space of a generation a leg was born.

Evolution don’t work like that. Micro and Macro are the SAME THING just viewed with different time samples. Micro is viewed on the generation timescale. Macro is viewed on the species timescale.


This message is a reply to:
 Message 48 by tjsrex, posted 08-31-2005 9:28 AM tjsrex has not yet responded

    
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