Speciies? you gotta be kidding.
 

Finally, somebody who seems to agree with me that species ( like most human categories) don't really exist and often just muddy up ones thinking.
Ran across this in Dawkins, The Ancestors Tale -

"If only all the intermediates were still alive, attempting to separate dogs from cats would be a doomed enterprise, as it is with the salamanders and the gulls." ( He had given an example of rings species issues using them.).

He uses a neat thought experiment - move back in time 1000 years at a pop. Each time take a breeding age male or female from the time you are in back one hop. They will be breedable with the older group. Now take a new one from there and hop back another 1000 years and they will be breedable. You'll eventually reach a point where you can't breed with the locals but your current 1000 year co-traveller will be able to. Did you just bump into a new species?

luckyme

Re: Speciies? you gotta be kidding.
 

Isn't the whole point of species to be able to classify creatures that are different into different groups? Obviously some groups of creatures are different from others so what is the problem?

Your thought experiment sounds a lot like the joke about boiling a frog.

Re: Speciies? you gotta be kidding.
 

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Isn't the whole point of species to be able to classify creatures that are different into different groups? Obviously some groups of creatures are different from others so what is the problem?

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Dawkins point was that if all the past relatives of cats and dogs hadn't gone extinct there would be a slow morphing of one category into the other category and there wouldn't be any meaningful place to draw the lines.
"without gaps in the fossil record our whole system for naming species would break down."

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Your thought experiment sounds a lot like the joke about boiling a frog.

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It's Dawkins illustration and he does use a cold-to-hot example also.

luckyme

Re: Speciies? you gotta be kidding.
 

I think the near ubiquitous tendency of various populations to form self contained breeding groups which share strongly related phenotypes, is sufficient to justify species classifications.

Re: Speciies? you gotta be kidding.
 

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Finally, somebody who seems to agree with me that species ( like most human categories) don't really exist and often just muddy up ones thinking.

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This is old news to biologists. Species are a division placed by human minds upon populations if living things, and not the other way around.

Oh, and you don't even need to go back in time to explain this. Ring Species

Re: Speciies? you gotta be kidding.
 

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I think the near ubiquitous tendency of various populations to form self contained breeding groups which share strongly related phenotypes, is sufficient to justify species classifications.

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It only works because all the people between 5ft and 7ft died off so now it's easier to point to "tall people" and "short people".

Ring species mirror the morphing of evolution and the useful but troublesome 'naming of species' issue. Looked back over time we are all ring species.

luckyme

Re: Speciies? you gotta be kidding.
 

This is a topic that always sticks in my craw. People make it out to be that there's no way to separate these groups into any legitimate categories and that just isn't true with the overwhelming majority of animals (ring-species aside).

Of course species breaks are impossible to locate if you go over the entire time. You're right that the point is that with all the die-off there are reproductively isolated groups in existence that have different selection pressures and evolutionary histories because of that isolation.
Without considering these groups different species we wouldn't have near the understanding of evolution we do.

Re: Speciies? you gotta be kidding.
 

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This is a topic that always sticks in my craw. People make it out to be that there's no way to separate these groups into any legitimate categories and that just isn't true with the overwhelming majority of animals (ring-species aside).

Of course species breaks are impossible to locate if you go over the entire time. You're right that the point is that with all the die-off there are reproductively isolated groups in existence that have different selection pressures and evolutionary histories because of that isolation.
Without considering these groups different species we wouldn't have near the understanding of evolution we do.

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If a strange catastrophe hits earth and the only groups left are blond swedes and dark pygmies then we can legitimately talk about 'races'? If we slowly discover pockets of groups one at a time, at which point do we start to claim that race is a very arbitrary concept, perhaps not even that useful?

Erasing the connections between two trait groups shouldn't change are view of them if the distinction was solid, but if we find two 'species' on opposite sides of a mountain and years later discover they are part of a ring ... what changed? we knew they were part of an unseen ring before we discovered the other pieces.

luckyme

Re: Speciies? you gotta be kidding.
 

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This is a topic that always sticks in my craw. People make it out to be that there's no way to separate these groups into any legitimate categories and that just isn't true with the overwhelming majority of animals (ring-species aside).

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This is more a tangent than a topic specific question, but is it a valid refutation point to 'set aside' the main evidence that shows the flaw in the original claim?

luckyme

Re: Speciies? you gotta be kidding.
 

[ QUOTE ]
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This is a topic that always sticks in my craw. People make it out to be that there's no way to separate these groups into any legitimate categories and that just isn't true with the overwhelming majority of animals (ring-species aside).

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This is more a tangent than a topic specific question, but is it a valid refutation point to 'set aside' the main evidence that shows the flaw in the original claim?

luckyme

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I think my contention is that it's not a flaw in the original claim. Evolutionary scientists accept that continuum, but for any time there are reproductively isolated groups that can be called "species"