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Anytime evolution is mentioned I think of that book and Jean's clan of the cave bear series.

   

The trait for height (and for that matter, age expectancy) was already there and has probably been there for a while. Good nutrition, sanitary conditions and medical science has just "exposed" the trait.

To make it perfectly clear, I'm not proposing controlling human reproduction.
I know we're evolving and nothing can stop that (well, except for total annihilation).

Although I would consider this a success (from Wiki) :
...A similar screening policy (including prenatal screening and abortion) intended to reduce the incidence of thalassemia exists on both sides of the island of Cyprus. Since the program's implementation in the 1970s, it has reduced the ratio of children born with the hereditary blood disease from 1 out of every 158 births to almost zero. Tests for the gene are compulsory for both partners, prior to church wedding.

I just wonder what traits today are being passed on to future generations and what's driving this selection.

   

Loved that one too, although the last in the series was getting to be a pain to read.
Some great "sex scenes".

   

Maybe just going back to the title of this topic would be constructive.

Richard Dawkins Admits Life Was Intelligently Designed


He didn’t admit it. Period.

He responded to a hypothetical question and never made an admission to the existence of God.

   

Not exactly. The trait for height is preferred, to some degree, which means taller people are mating with taller people, making the overall species taller. It's more than juat already HAVING the trait. If it weren't, then there wouldn't be ANY short people (at least among those that can afford adequate food).

   

What she is describing is Lamarckian evolution, where individual organisms, by being stressed, can change. Darwinian evolution is about changes within species caused by environmental stress. If enough change happens and the new type of individual is isolated from the original, for long enough, than a new species emerges. Most evolution appears to have happened in "spurts" caused by changes in the availability of habitats. Breaking up supercontinents, rapid changes in world weather or the earth being struck by some large object create the conditions where niches are emptied and available or new niches were created.

   

See: Cambrian Explosion.

   

Is that the company that removes tree stumps?

   

Smartass

   

Well, almost. "Darwinian Evolution" (I prefer the term Natural Selection) doesn't come from "environmental stress"...it comes from SURVIVING environment. That's an EXTREMELY important distinction.

   

OK, I'll try to explain what I mean a bit better.
Height is determined not by 1 or 2 genes but by many, and a lot of the genes have not been identified yet.

True that genetically, we are getting taller. So I' m not saying that you're wrong, only that we're both right.

A lot of children are taller then their parents were. I'm in this group as I'm taller then my father and all my "blood" uncles on both sides. I do have a few cousins that are as tall or taller than me (out of about 70 cousins, that's not much of a surprise).

The experts cannot explain this by genetics alone except to say that the genes for that height were there before but other factors influence our final height.

Here's a link that explains it a bit more, probably not the best one but the only one I could find on short notice.
http://www.newton.dep.anl.gov/askasci/m ... e00125.htm

   

Don't want to argue sematics , but environment is stress, unless an organism is perfectly adapted to what it lives in. Then, if it is not, when it reproduces, the offspring that are best suited to the niche they live in will survive to reproduce.

   

Nor do I want to argue semantics. It's just important (not for you, per se, but for others less versed in science) to understand that organisms do not change. They either survive or die. If they survive, their genetic information is passed on.

   

So a gopher in Nunavut and a gopher here in southern alberta are the same except the northen ones bulk up 5 times faster in 3 months time before hibernating for the winter.
So did they change because the environment got cold or did they adapt to the cold through survival of the fittest and passing on only the tough gene's?

   

But they do change. If there wasn't any change, then we'll still all be uni-cellular organisms living in the oceans.

Genetic mutations are very important in the development of life on earth.
They can have 1 of 3 effects. The organism with the mutated gene:
1) is less adapted to the environment and he will either die before producing offspring or will not be able to do so.
2) is equally adapted and has as much chance as the others. This mutation may come into play later on if passed on to his offspring.
3) is better adapted and has more chance to pass on this gene. In the long run, this mutation may become the norm in the species.

   

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