Kelzie said:
You know what they say. The person who starts slinging mud first has lost the debate. And it's a genetic mutation. And seeing as the vast minority of the world's population has this mutation, I stand by my word.
Well, you haven't started to sling any mud yet, so you're still in the race. Meanwhile, I'll stand by my statement that you're not employing the correct definitions of the words. That is not mudslinging, at best it's an opportunity to clarify communication. And again, you seem to be using a word and attempting to charge it with negative connotations. Mutation or not, it's still an adaptation.
I could postulate that since european winters are harsher than elsewhere, then babies that could consume cow's milk were more likely to survive. But that's just guessing. You can point to the Arctic winters and the eskimos, I suppose, but they didn't have cows. No grass. Not only that, there's no saying that a adaptation peculiar to one place and circumstance must also arise in similar places and circumstances. Evolution doesn't work that way.
Kelzie said:
This analogy makes no sense. The people that can digest the milk live in areas where they don't need the extra calories (N. America and W. Europe).
I can't believe you're suggesting that the ability to absorb extra calories isn't an adaptational advantage. I fail to see the logic in anyone claiming that an increased ability to absorb calories is not a positive survival characteristic for any animal. Explain this.
Conditions change faster than characteristics. Overly specialized species, ie "efficient" ones, find themselves in trouble when the environment starts to exceed their adaptation. What would koala bears do if a virus started killing all the eucalyptus trees? How did the Irish fare when the fungal blight wrecked their potatoes?
As far as the "need" of extra calories is concerned, you're projecting your perceptions of current conditions onto earlier eras. African tribes to this day go raid termite mounds to collect the bugs because they need the protein.
Now, North America is not relevant to the discussion, the trait developed in Europe. Nor did the trait develop recently, after industrialized farming ended famine. It predated the invention of hay, even. The trait apparently developed in people living in the primitive conditions and the harsh climes of Northern Europe.
Kelzie said:
The only way to make your analogy work is if there was no mosquitos. Now you have the choice of not dying now, or dying of cancer 20 years later. Which is it?
Okay, forget the analogy. I can flip analogies out like a blackjack dealer in Vegas. All I'm trying to say is that milk has to be examined on a cost/benefit basis. Hemlock/no hemlock is a pretty clear choice. Milk isn't that clear-cut, and certainly when the digestive enzyme appeared none of the potential hazards of milk would have been apparent. Not only did they not live long enough for the alleged problems to occur, they lacked the ability to make the connection.
How this relates to the milk issue is that before the wonders of gasoline powered tractors, every once in a while crops would fail, the weather wouldn't cooperate, the arrows refused to hit the deer, and your babies would start to starve. People that were more efficient at absorbing milk were more likely to survive. The widespread presence of the enzyme in Northern European populations is a sure indication that the adaptation did have some usefulness, just like white skin.
Kelzie said:
And yet, they are lactose intolerent. Point?
They still drink the milk. They even mix it with cow blood as a special kind of pink Quik. Yuk. But drink it they do. They may be lactose intolerant, but they have to be drawing sustenance from the fats and proteins nonetheless. Recall what I said about similar circumstances not necessarily leading to similar results.
Kelzie said:
Actual, the gene mutation occured thousands of years ago. A mere fraction of the time that humans have been evolving. Obviously, we didn't need the calories that badly.
And the trait doesn't extend across then entire species, either. Needless to say, there's an enormous number of genetic anomalies from group to group.
And, to make things perfectly clear, I'm not necessarily disagreeing that milk isn't a potential hazard. Almost any food you can name taken in excess is. And certainly modern adults don't need to drink the stuff. But let's put it this way...what's easier, feeding a kid milk to meet his calcium requirements, or trying to stuff him full of spinach every night? I think I'm lucky that my girls like broccoli and hate soda, but there are limits to what they'll do.