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Author Topic:   Dogs will be Dogs will be ???
randman 
Suspended Member (Idle past 5014 days)
Posts: 6367
Joined: 05-26-2005


Message 72 of 331 (468860)
06-01-2008 11:27 PM
Reply to: Message 1 by RAZD
12-05-2007 8:00 PM


Re: Time for a little definition of what macroevolution is.
Interesting the idea of trying to set a metric of change to examine facts by. I've been saying for some time that evos need to do that to substantiate their claims, specifically their claims of fossil rarity as being a good excuse for transitions being absent from the fossil record. One response was that it's impossible, but you seem to be doing this with your initial post in relation to cats and dogs, etc,....It would be interesting to apply this for other species such as whales where you have some differing whale genera that can mate and produce offspring (even classified different subfamilies by some), and yet seeming closer related species cannot do that.
This relates to your OP because there is a definite range of traits that can be significantly wider for the same sort of creature (creatures that can mate) than there is even apparently between species that cannot.....or so it seems.
However, this really doesn't tell us much in terms of the EvC debate. It's not like creationism doesn't predict the same results. It does. Creationism in fact predicts specific ranges of evolution occur within a baramin or kind. So it would not be surprising to see some ranges expanded to the point that maybe, for some features, the Fox does appear as similar to the cat.
Curiously though, I see your post as somewhat evidence against evolution, as the Fox should be more closely resembling other canines than cats since presumably they are genetically and evolutionary closer in relations. The fact this is not the case is not supportive of evo theory.

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randman 
Suspended Member (Idle past 5014 days)
Posts: 6367
Joined: 05-26-2005


Message 74 of 331 (468866)
06-02-2008 12:31 AM
Reply to: Message 73 by RAZD
06-01-2008 11:58 PM


Re: Please no off topic responses.
First off, non-related (or distantly related) species that share traits does not violate evolution in any way. See Sugar Gliders and Flying Squirrels as an example of convergent evolution, but more important of sharing analogous traits but not homologous traits.
Second, the fact that canines and felines share so many traits is because they have a fairly recent common ancestor.
You don't see a contradiction between the 1st and 2nd point? If similar traits can arise via convergent evolution, then doesn't it make sense that foxes and cats seem more similar due to the fact they occupy a different habitat? The fact they theoritically share common ancestor does not explain why foxes are not more similar to dogs, if that is even the case. Considering they are classified in the canine family, it strikes me that you are factually wrong, but more to the point, the similarities between foxes and cats are not due to common ancestry. Otherwise, they'd be more similar to dogs. Right? Since they presumably have a closer common ancestor to dogs.

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randman 
Suspended Member (Idle past 5014 days)
Posts: 6367
Joined: 05-26-2005


Message 75 of 331 (468868)
06-02-2008 12:37 AM
Reply to: Message 73 by RAZD
06-01-2008 11:58 PM


Re: Please no off topic responses.
RAZD, you are the one that introduced transitionals and the fossil record, not me, or perhaps you don't recall these comments?
If this is not convincing enough we can go further back in time to extend the analysis above (where we started with eohippus\Hyracotheriumabove):
From Transitional Fossils FAQ by Kathleen Hunt:
Perhaps you just want to discuss horses and dogs? But at the same time, you opened this door into transitionals and how there can be greater similarity within closely related species than more distantly related species. If it's off-topic, please don't complain as if I am the one that brought it up.
Edited by randman, : No reason given.

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randman 
Suspended Member (Idle past 5014 days)
Posts: 6367
Joined: 05-26-2005


Message 76 of 331 (468869)
06-02-2008 12:44 AM
Reply to: Message 59 by RAZD
05-17-2008 9:38 AM


quite a bit on fossils and transitionals from you
The horse fossils disagree with you. Care to continue?
On topic of off-topic? Horses are not the same as dogs and cats....?
The only difference between natural selection and human selection is that the traits selected are beneficial to us rather than to the wolf, or fox, or cat, or cow ... etc etc etc. The process that develops the traits selected is natural
But aren't dog breeds, pur-breds, less able to evolve further? Seems that evolution is limited since the more evolution, the less genetic variation within a species and so this is evidence for creationism, not Darwinism. Btw, this is answering and discussing your points that you brought up.
Additionally, you do realize that some foxes can and do mate with some wolves. Considering that fact, it's hard to see how someone can use foxes and wolves as somehow evidence against creationism, evolution prescribed within a kind or baramin. Once again, I don't see how your points advance any valid criticism of creationism.
Can foxes mate with cats or something?

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randman 
Suspended Member (Idle past 5014 days)
Posts: 6367
Joined: 05-26-2005


Message 77 of 331 (468876)
06-02-2008 2:07 AM
Reply to: Message 59 by RAZD
05-17-2008 9:38 AM


a different take on the 40 year experiment you cite
The experimental investigation of these hypotheses involved forty years of inbreeding for tameness in thirty or so generations of silver foxes. The results are impressive. On the one hand, foxes that were bred for tameness also tended to share a number of other phenotypic traits. Unlike their feral cousins, they tend to evolve floppy ears, brown moulting, grey hairs, short curly tails, short legs and piebald coloration (in particular, white flashes). Inbreeding for tameness also had characteristic effects on the reproductive cycles of the foxes and on the average size of their litters. And these are all traits that other domestic animals (dogs, cats, goats, cows) also tend to have. An adaptationist might well wonder what it is about dogs, cats etc that makes curly tails good for their fitness in an ecology of domestication. The answer, apparently, is ”nothing’. Curly tails aren’t fitness enhancing, they just happen to be linked to tameness, so selection for the second willy-nilly selects the first.
This case is much like that of spandrels, but much worse from an adaptationist’s point of view. You can explain the linkage between domes, arches and spandrels; the geometry and mechanics of the situation demands it. But the ancillary phenotypic effects of selection for tameness seem to be perfectly arbitrary. In particular, they apparently aren’t adaptations; there isn’t any teleological explanation - any explanation in terms of fitness - as to why domesticated animals tend to have floppy ears. They just do. It’s possible, of course, that channelling and free-riding are just flukes and that most or all of the other evolutionary determinants of phenotypic structure are exogenous. It’s also possible that palaeontologists will someday dig up fossilised pigs with wings. But don’t bet on it.
So what’s the moral of all this? Most immediately, it’s that the classical Darwinist account of evolution as primarily driven by natural selection is in trouble on both conceptual and empirical grounds. Darwin was too much an environmentalist. He seems to have been seduced by an analogy to selective breeding, with natural selection operating in place of the breeder. But this analogy is patently flawed; selective breeding is performed only by creatures with minds, and natural selection doesn’t have one of those. The alternative possibility to Darwin’s is that the direction of phenotypic change is very largely determined by endogenous variables. The current literature suggests that alterations in the timing of genetically controlled developmental processes is often the endogenous variable of choice; hence the ”devo’ in ”evo-devo’.
http://www.lrb.co.uk/v29/n20/fodo01_.html
Apparently, some see this as fairly strong evidence for the need of a reinterpretation of evo theory away from adaptionism and raises questions about the origin of specific traits. Specificaly, this experiment shows dog traits arising not due to conferred selective advantage but simply because such traits are associated with or arise with, incident to, a specific behaviour. In other words, a whole host of traits come when a specific behaviour is selected for, but the traits themselves are not tied to any selective advantage. They just get expressed with tamer canines.
Now applying this to your OP, the similar traits between cats and foxes are likely nothing but the fact similarities are expressed per different behaviour. Somehow the genetics that enable specific behaviour also tend to produce similar traits, but that doesn't mean the traits themselves confer a selective advantage.
So considering genes for specific morphological and behavioural similarities may well likely be similar, there really is no reason to assume these traits are the result of common ancestry at all. In fact, you admit similar traits can arise without them being conferred via common ancestry, correct?
So where is the beef on the fox being similar to cats claim? I just don't see it yet.

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