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Cat lineage - Home of the terminally single
pendlemac
pendlemac
Cat lineage
It appears they've traced the cat family tree back to a common ancestor.

See BBC page here.

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miss_next From: miss_next Date: January 7th, 2006 08:25 am (UTC) (Link)
I read the article, which was interesting, and then I noticed it had a link to this one.

All right. Will these clever scientists, then, please explain why my Minsky is so ecstatically fond of honey? :-)
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martinoh From: martinoh Date: January 7th, 2006 12:17 pm (UTC) (Link)
Your question surely presupposes that (a) a carnivorous diet is the most efficient the cat could have developed and (b) that being able to determine sweetness as a component of taste would automatically have resulted in cats adopting a sub-optimal diet? If either of these are untrue then the mutation conveys no advantage but does represent a loss in capability relative to related species.
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martinoh From: martinoh Date: January 7th, 2006 02:50 pm (UTC) (Link)
I'm obviously reading the article slightly differently; there is a suggestion that the mutation may have been responsible for shaping cats' diet, but not on whether this would have made them any less able to survive as a species. Certainly I can't find anything to suggest that cats would necessarily have adopted unhealthy eating patterns based purely on their ability to taste sweetness.

No information is given on whether the taste mutation occurred before or after the development of poor digestive capability for most carbohydrate-bearing foods, so it's impossible to infer whether losing the ability to taste sweetness was a low disadvantage mutation because digestive changes had already biased against such items or vice versa.

As to (a) - well this is where one's particular brand of evolution theory comes to the fore; for me, the survival of a species is proof that its adaptation to the environment is not bad enough to preclude it, rather than proof that it is optimal. Other's mileage varies considerably.
pendlemac From: pendlemac Date: January 7th, 2006 09:40 pm (UTC) (Link)
Now what I want to know is why a mutation that helps cats be efficient carnivores is a “defect.”

I think the word 'defective' is simply being used as shorthand for 'the gene doesn't do what it does in all the other creatues it's found in' and it's not meant to imply that the result is an inferior animal.

I suppose a better way of putting it would be to use the word 'error' instead of 'defect'.
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