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Author Topic:   Are you a mutant? x man? Can you drink milk?
bluegenes
Member (Idle past 862 days)
Posts: 3119
From: U.K.
Joined: 01-24-2007


(1)
Message 7 of 31 (728496)
05-29-2014 5:13 PM
Reply to: Message 4 by frako
05-29-2014 12:58 PM


frako writes:

We whiteys don't need that ability any-more as we drink milk, so we have less melanin.

And:

frako in the O.P. writes:

Its also how we whiteys became white more milk you can drink more vitamin D the less melanin you need to make your own.

No. Melanin doesn't help us make vitamin D, it hinders that process. "Whiteys" have lost melanin because they live in cool, cloudy climates with short winter days. Whiteys are better at making vitamin D from sunlight than those with high melanin.

Although it seems plausible that vitamin D might have been a factor in the high rate of lactase persistence in northern Europeans, it may not be that important. There are hotspots in Africa and the Arabian peninsula as well, as the map in the article you linked to shows.


This message is a reply to:
 Message 4 by frako, posted 05-29-2014 12:58 PM frako has not yet responded

  
bluegenes
Member (Idle past 862 days)
Posts: 3119
From: U.K.
Joined: 01-24-2007


(2)
Message 26 of 31 (728772)
06-02-2014 9:09 PM
Reply to: Message 22 by Faith
06-01-2014 8:13 PM


Almost definitely a gain.
Faith writes:

Typical bunch of evo myths if you ask me. None of the references or the participants on the thread has offered evidence for these supposed mutations that have made lactose tolerance possible, or for the time period in which this supposedly happened in certain parts of the world. It's asserted and believed and that's it.

How many of the research papers on the subject did you read before forming that opinion?

Faith writes:

Are these mutations the addition of specific alleles for a specific gene or exactly what are they? And how do you know they are mutations?

Lactose digestion and the evolutionary genetics of lactase persistence

Faith writes:

I would of course have my own usual guess. The ability to digest milk would have to have been built in to the human genome because milk is such a nutritious food.

Well, apart from the obvious point that so is the grass that our domesticated animals process to make it, you could test that hypothesis against observations. You could observe that genetic drift would be extremely unlikely to remove Lactase persistence from most of the population in just the few hundred generations your YEC model allows, and most people in the world do not have it (~65%).

Then you could think of an experiment to test your hypothesis directly. As it would predict that stone age Europeans would all, or nearly all, have the Lactase persistent allele that most Northern Europeans still have, you could extract DNA from the bones of people found on Neolithic sites, and check them for the LP allele.

If you find that all your samples have it, that's in keeping with your hypothesis, but if you find that none of them do, then you've pretty well falsified your hypothesis.

Fortunately for you, someone has already done the work for you, saving YEC scientists the trouble.

Fred Flintstone couldn't drink milk

Oops!


This message is a reply to:
 Message 22 by Faith, posted 06-01-2014 8:13 PM Faith has responded

Replies to this message:
 Message 28 by Faith, posted 06-02-2014 11:25 PM bluegenes has responded

  
bluegenes
Member (Idle past 862 days)
Posts: 3119
From: U.K.
Joined: 01-24-2007


(3)
Message 29 of 31 (728792)
06-03-2014 2:32 AM
Reply to: Message 28 by Faith
06-02-2014 11:25 PM


Study the relevant research before expressing opinions.
Faith writes:

This is just the usual flimflam runaround.

"Flimflam runaround" pretty much describes every post you make about biology.

Faith writes:

I believe it is your job to present whatever evidence you think you have so that a reader of the thread could follow it without having to open links.

Which we can take as meaning that, when presented with evidence from the relevant literature that supports the O.P., you want to continue to pretend that no-one has presented any evidence that supports the O.P., which is what you claimed in the post I replied to.

The second paper I linked to shows that our Neolithic ancestors did not have the allele for Lactase persistence at near fixation in the way that modern north-western Europeans do. It wasn't present in any of the eight Neolithic individuals examined, or in one Mesolithic individual, which shows that your unsupported assertion that Lactase persistence was the historical norm was clearly wrong.

If you can't read and understand papers like these, then you shouldn't be expressing your opinions on biology. Those opinions are meaningless fantasy if you can't support them.

You are the one disagreeing with the research described in those two papers, and the conclusions of specialists in their field. If you want to do that, you need to read the papers, and give the technical reasons for your disagreement.

You also need to understand the point I made about drift in the last post, which you ignored.

Now, stop flimflamming around, and if you want to discuss biology, learn how to do it like an informed adult.

What the current evidence points to is a number of different mutations in different geographical regions that led to lactase persistence and have faced positive selection over the last few thousand years in cultures that do dairying.

Read the papers. They contain some of the evidence that supports that point.

Lactose digestion and the evolutionary genetics of lactase persistence

Fred Flintstone couldn't drink milk


This message is a reply to:
 Message 28 by Faith, posted 06-02-2014 11:25 PM Faith has not yet responded

  
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