Question by Alexandria: Why would scientists prefer to theorize history to fit a model instead of just admitting they dont know?
http://en.wikipedia.org/wiki/Chachapoyas_culture
these peruvian indians were pale and blond. article said they became pale and blond by assortative mating and share a common ancestor with other amerindians. can asians assortative mate and become blond too?
i didnt get response in other category, so i repost here.
Michael: not saying you are wrong about the indians. but assuming that they share a common RECENT ancestor with other indians, as the article states. it would take a LONG time to change characteristics, i would imagine. and as to dog breeding, humans are very careful in selection to perfect a breed. could the indians have selected their mates so carefully without planning? are they advanced enough to do selective breeding of themselves? it just sounds fishy.

Best answer:

Answer by Michael B
Never mind Indians in Peru – I’ll just answer your main question.

Scientists theorise, about past, present and future events, precisely because they don’t know. They gather data; they try to explain it. They come up with a theory, and go out looking for more data to check on it. Sometimes the theory bites the dust, sometimes it survives. It’s the way science works.

Sometimes scientists become attached to their own theories to the point where they become blind to the evidence. This doesn’t, in the long term, matter – there are always other scientists about, and if your results can’t be reproduced, bang goes your theory anyway.

Note that a scientific “law” is never really a law – it is just the best theory (the one which matches the available data most closely) and it will be chucked out when a better fit is available. Even Newton had to give way (to Einstein) as research rolled on.

As for your other question: preferential mating (spontaneous or planned) can have far-reaching results. Planned preferences produced the Great Dane and the Pekinese. If there were a settled and long-lasting preference for fairness among a certain population, or an evolutionary advantage to be gained by a pale complexion, it would be no surprise to find that the population steadily became lighter, whatever their ancestors looked like. This is no mystery.

Hope this helps.

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