For hammegk: How to turn a cat into a dog.

[KingMerv00]

For some time, there has been a debate on this board over the definition of species. hammegk has taken a common sense point of view. "A dog is a dog, a cat is a cat." He also believes that evolution may not be able to account for macro-evolution.

Let's say these lists of letters are a complete DNA profile:

Cat: A-B-C-D-E-F-G
Dog: H-I-J-K-L-M-N

Mutation is capable of changing these letters. Selection (natural or otherwise) can make some letter changes preferable over others.

Now some questions:

1) If you combine mutation and natural selection, why couldn't you turn "A-B-C-D-E-F-G" into "H-I-J-K-L-M-N" one letter at a time?

2) Wouldn't changing an animal's DNA sequence be sufficient to create a completely different looking species? It's only chemicals after all.

3) When exactly does a cat become a dog? When 50% of the letters are the same? 51%? 100%?


hammegk: I apologize if I have misrepresented any of your views in the above post. You may have altered your views sometime in the past or addressed these isses. If so, whoops.

[Goshawk]

Mutation is capable of changing these letters. Selection (natural or otherwise) can make some letter changes preferable over others.
Yes, but selection needs to have an environmental reason to keep those changes.

What is the difference between a cat and a dog? A cat hunts at night and is not social; a dog hunts in the day and is social (yes, I know that's a vast oversimplication, but...) So if a dog suddenly turned up with a mutation that enabled it to see better at night, it wouldn't do it any good, because it's already hard-wired to hunt with its pack, and its pack would already be bedded down for the night. And when the pack went hunting during the day, the night-vision dog wouldn't be at any particular advantage.

And in order to pass on its genes for better night vision it would have to be an alpha animal. So you'd have to have, not only the mutation itself, but also other conditions would have to be met before that dog would be able to pass on its genes for better night vision.

So say it did manage to pass on those genes; its offspring would then find themselves in direct competition with already existing night-hunters, i.e. the cats, competition that had been doing it for a lot longer, and some of whose larger members, like lynx, might find the night-vision dogs, newly roaming around in the forest at night, to be easy prey.

So there's more to it than simply switching the genes one at a time, running the possible mathematical combinations like a Jumble puzzle or something until you manage to make "CAT" spell "DOG".

[KingMerv00]

Yes, but selection needs to have an environmental reason to keep those changes.

What is the difference between a cat and a dog? A cat hunts at night and is not social; a dog hunts in the day and is social (yes, I know that's a vast oversimplication, but...) So if a dog suddenly turned up with a mutation that enabled it to see better at night, it wouldn't do it any good, because it's already hard-wired to hunt with its pack, and its pack would already be bedded down for the night. And when the pack went hunting during the day, the night-vision dog wouldn't be at any particular advantage.

And in order to pass on its genes for better night vision it would have to be an alpha animal. So you'd have to have, not only the mutation itself, but also other conditions would have to be met before that dog would be able to pass on its genes for better night vision.

So say it did manage to pass on those genes; its offspring would then find themselves in direct competition with already existing night-hunters, i.e. the cats, competition that had been doing it for a lot longer, and some of whose larger members, like lynx, might find the night-vision dogs, newly roaming around in the forest at night, to be easy prey.

So there's more to it than simply switching the genes one at a time, running the possible mathematical combinations like a Jumble puzzle or something until you manage to make "CAT" spell "DOG".

I intentionally left out specifics like this because I'm trying to get some simple common ground with hammegk. If you like, imagine the entire process is caused by human intervention.

[drkitten]

Yes, but selection needs to have an environmental reason to keep those changes.

What is the difference between a cat and a dog? A cat hunts at night and is not social; a dog hunts in the day and is social (yes, I know that's a vast oversimplication, but...)

So you don't think there are social cats? (Hint: think lions.)

For that matter, dingos are nocturnal dogs (and tend to hunt alone). Foxes are also nocturnal solitary hunters, although not strictly speaking dogs.

In fact, the very conditions that you cite are part of the reason why in an environment free of cats, (some) dogs would be likely to evolve cat-like traits (and vice versa). If the world is full of diurnal, pack-hunting dogs, than a mutant dog that hunts alone at night would be able to feed itself on other animals that its more genetically conservative relatives missed.

Of course, this raises the question of where one might find an environment free of cats, such as a large island that's more or less isolated from the rest of the world, but to which a few founding dogs might be able to spread and rapidly adapt. Possibly one with a really pretty opera house and good beer.

[HeyLeroy]

slightly relevent derail (http://206.225.95.123/forumlive/showthread.php?postid=1288123#post1288123)

[William Parcher]

The original question is misleading because it suggests something specific, when the question is really one of general macro-evolution.

Cats never became dogs and vice-versa. We shouldn't even expect that to occur in the future. The common ancestor of cats and dogs was neither a cat nor a dog.

The better question (given as a statement) is, "How a felid lineage becomes something that we no longer classify as a felid." This is only a question about macro-evolution.

The examples given in this thread about how natural selection would form new species is insufficient IN ITSELF to automatically predict macro-evolution. Macro-evolution is surely a possible consequence of speciation, but it would not necessarily be automatic. A macro-evolutionary "event" is always a speciation event, but not vice-versa.

There are a thousand more things that could be said about this issue. But because the arguments between creationists (and IDers) and evolutionists is secular in its premise... it creates certain obstacles that are outside of science. There is the issue of macro-evolution as studied within science itself and then there is the issue of trying to argue and educate a consortium of folks who misunderstand what macro-evolution is in the very first place. There is the danger of creating further confusion and fuel for ongoing disagreement by trying to explain things in pedestrian terms or using commonsense token examples or ideas.

[KingMerv00]

The original question is misleading because it suggests something specific, when the question is really one of general macro-evolution.

Cats never became dogs and vice-versa. We shouldn't even expect that to occur in the future. The common ancestor of cats and dogs was neither a cat nor a dog.

I'm not sure how familiar you are with hammegk but, near as I can tell, he thinks the idea of a cat evolving into a dog is impossible in principle and that there could never be an intermediate between the two species.

I'm trying to find out why.

[Goshawk]

Dr.Kitten, I said it was a "vast oversimplification". ;)

[William Parcher]

I'm not sure how familiar you are with hammegk but, near as I can tell, he thinks the idea of a cat evolving into a dog is impossible in principle and that there could never be an intermediate between the two species.

I'm trying to find out why.

I am somewhat familiar with his style of argument after reading about 20 of his postings. He is not unique. There are legions of people who think and argue like him about evolution. They seem like stubborn crackpots who are (for whatever reasons) incapable or unwilling to understand what evolution is and how it may operate to change organisms over time. But in an important way, his ilk benefits evolutionists because it forces them to try to explain things in a grandly comprehensive way that is devoid of confusions (both real and potential). The same sorts of confusions can occur to smart people who are genuinely trying to get a handle on things, as opposed to being just plain obstinate.

The idea that a cat could evolve into a dog is impossible in principle. This is because the example is using cats and dogs and we already have scientific definitions of those animals. What IS possible in principle (and real life), is that a cat lineage could evolve into something that we no longer classify as a cat.

Even if a cat lineage evolved into something that looked and acted exactly like a dog... we could not call that animal a dog. Maybe we would call it a Wimbic. We could then say that the Wimbics and dogs show convergent evolution. The Wimbic cannot be a dog because a dog is something that not only looks and acts like a dog, but also (importantly) is from the ancestral lineage(s) that leads directly to dogs. How (or when) does a Walking Stick (insect) become a plant?

You might deprive Hammy of some stubborness if you ditch the cat-to-dog scenario and go for the cat-to-Wimbic scenario. Maybe not.

Of course there would be "intermediates" between cat and Wimbic. But the real issue is trying to decide exactly WHEN you stop calling it a cat and switch to calling it a Wimbic. That can happen while you still have cats running around. This gets to the idea that "missing link" has great potential to be misunderstood and misused. According to the way that we classify animals, there could never be a Catwimbic. There can only be cats and/or Wimbics.

[Dragon]

According to the way that we classify animals, there could never be a Catwimbic. There can only be cats and/or Wimbics.Good point, WP - I think the way we classify animals is definitely part of Hammy's problem or, at least, it helps him put up his (straw?) barrier which makes speciation/macro evolution such an issue for him. I tried in one of the threads to get Hammy to look up ring species, perhaps I should have pushed the point more...

[Paul C. Anagnostopoulos]

I know that wimbic would look just like this:

http://www.resourceinvestor.com/pebble.asp?relid=10958

~~ Paul

[Bronze Dog]

I know that wimbic would look just like this:

http://www.resourceinvestor.com/pebble.asp?relid=10958

~~ Paul
GEEZE! Give us a little warning about what you link to.

[Paul C. Anagnostopoulos]

Oh, sorry, I thought almost everyone had already seen that monstrosity. Of course, how would you know that's what I linked? :D

~~ Paul

[Soapy Sam]

You know, if nobody had ever come up with the concept of "a species", dogs and cats would be functionally identical terrestrial carnivorous mammals.
As would humans and chimps.
Which would make it OK.
But all the wife and I get is hatemail.
Mostly from other chimps. They're just jealous.

The whole debate is senseless.

[HeyLeroy]

You know, if nobody had ever come up with the concept of "a species", dogs and cats would be functionally identical terrestrial carnivorous mammals.
As would humans and chimps.
Which would make it OK.
But all the wife and I get is hatemail.
Mostly from other chimps. They're just jealous.

The whole debate is senseless.

Except for the whole dogs eating their own feces thing.
Sorry 'bout the hate-mail, I'll ask my uncle to knock it off.

BTW, sadly, Sam is now in doggy heaven (http://www.resourceinvestor.com/pebble.asp?relid=14838). Hope there's a lotta fireplugs there for him.

Funny, but I feel worse for him than I do for the guy in the obit in the thread I'm about to start over in religion.

[hammegk]

darned double post ....

[hammegk]

... if nobody had ever come up with the concept of "a species", dogs and cats would be functionally identical terrestrial carnivorous mammals.

As would humans and chimps.

I agree some people have difficulty seeing the difference in either; both genotype and phenotype disprove your (tongue-in-cheek?) comment.


As to making dogs from a cat, we're not quite at that level of understanding and technology, but darn close. :)

[Roboramma]

The idea that a cat could evolve into a dog is impossible in principle. This is because the example is using cats and dogs and we already have scientific definitions of those animals. What IS possible in principle (and real life), is that a cat lineage could evolve into something that we no longer classify as a cat.
I see your point WP, but I don't see that it's impossible.
Basically, it seems like you're saying that its impossible for us to predict the exact outcome of evolution, so to go from one specific genotype to another specific genotype (rather than simply an animal with certain broad characterists) is impossible.
Well, okay. I think a phrase is "so improbable the we would never expect it to happen." would be more appropriate.

Of course if you define "dog" as a creature whose ancestry is the same as other dogs, then it is impossible. If you define dog as a creature with a certain genetic makeup then it's just very improbable.

But I don't see why its necessarily impossible for a series of environments to exist such that the cat would evolve, one gene at a time, into a dog by the above definition.
No, that particular course of evolution would never happen. Neither would any other that we defined so specifically ahead of time. There is too much that's contingent upon circumstance.

Basically, I'm saying that this suggestion is like saying "if you flip a coin 100,000 times, flips number 357-372 will all be heads." which of course we couldn't say. But the idea that such evolution could occur is like saying "If you flip a coin 100,000 times at some point you will run across a series of heads 15 flips long." which is obviously true.

It seems like KingMerv's argument is trying to point out the latter, not the former.

[clarsct]

And here I thought I knew the answer.

1) douse the cat in gasoline
2) throw a lit match at it.
WOOF!


I'l just be leaving now...

[William Parcher]

I see your point WP, but I don't see that it's impossible.

I will try to explain why it is impossible.

Basically, it seems like you're saying that its impossible for us to predict the exact outcome of evolution, so to go from one specific genotype to another specific genotype (rather than simply an animal with certain broad characterists) is impossible.

No, I wasn't saying that it is impossible to predict the exact outcome of evolution. I might agree that that is true (under some circumstances), but predictibility is not germane to this discussion. My premise is based on only one kind of prediction: The prediction that evolutionists and cladists are not completely wrong about the evolution of life and how we study, understand and define it.

Well, okay. I think a phrase is "so improbable the we would never expect it to happen." would be more appropriate.

Probabilities (as you are suggesting) have nothing to do with this issue.

Of course if you define "dog" as a creature whose ancestry is the same as other dogs, then it is impossible. If you define dog as a creature with a certain genetic makeup then it's just very improbable.

We are not at liberty to redefine "dog" (Canidae) by stepping outside of the TOE and its conventions. If you try, you might actually be making an attempt at falsifying the TOE (whether you realize it or not).

The graphic representation (model) of the evolution of life is a branching tree (maybe a bush is better). Lineages are depicted as branches and twigs. The creation of any daughter lineage is represented by a new branch or twig. This is a real bifurcation and is also an instantaneous dichotomy (if it weren't, the creation of a new branch or twig would be undefinable and therefore unjustifiable). Since Canids (dogs) and Felids (cats) are already classified as seperate branches (according to cladistics), they cannot be the same branch. To suggest that a cat lineage could now (possibly) produce a daughter lineage that is truly a dog... is to suggest that the evolutionary model is maybe not a branching tree, but is instead a solid cone. With a solid cone, there are no such thing as branchings, lineages or bifurcations. It's just one big homogenous mass. No part of the cone is really any different than any other part.

Both the tree and the cone are represented three-dimensionally as models. The axes are space (which is inherently represented as three-dimensional) and time (which is represented as linear). To look at either model as a sample from present time we would take a cross-sectioned slice. The sliced tree model would look like an array of dots (or points) that are cuts through the branches and twigs with empty space in between them. The sliced solid cone model would look like a solid disc. To move from one area to another in the sliced tree, you have to jump from one point to the next and so on. To move through the sliced cone, you simply glide across the surface like a skater on ice. The points in the sliced tree are as different and definable as are earthworms and elephants. The surface of the sliced cone may contain worms and elephants, but their differential descriptions would sound like someone trying to distinguish one square foot of ice with another square foot on a perfect ice rink.

But I don't see why its necessarily impossible for a series of environments to exist such that the cat would evolve, one gene at a time, into a dog by the above definition. No, that particular course of evolution would never happen. Neither would any other that we defined so specifically ahead of time. There is too much that's contingent upon circumstance.

That doesn't matter, even if it could or did happen.

Basically, I'm saying that this suggestion is like saying "if you flip a coin 100,000 times, flips number 357-372 will all be heads." which of course we couldn't say. But the idea that such evolution could occur is like saying "If you flip a coin 100,000 times at some point you will run across a series of heads 15 flips long." which is obviously true.

The coin tossing is a red herring analogy. Even if a cat lineage produced a genotype and phenotype that was indistinguishable from any dog... cladists (presumably) could not call it a true dog because of its KNOWN ancestry. What we would have is the most extraordinary case of convergent evolution ever witnessed. The Wimbic is indistinguishable from a dog, but it is NOT a dog because it has non-dog evolutionary ancestry. Maybe that's the time when we put the international community of cladists on suicide watch. Just kidding... sorta.

It seems like KingMerv's argument is trying to point out the latter, not the former.

What argument? What point?