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No, actually I have perfect vision. Nearsightedness does run in the family. When I say run in the family, I mean more people have it than don't. I just didn't get those genes. I said that more people live with defects today and I was informed by another CD member that this isn't the case. Who do I believe?
Well, whomever you wish to, based on research plus your own experience and a dash of common sense thrown in. As for me, yes, I do believe more people live with "defects" today. Imagine how many children in former generations would have been dead without insulin. (I'm talking about Type I or "childhood" diabetes, not obesity-related diabetes since it could be argued that without the obesity we wouldn't need the insulin anyway.)
A normal pregnancy is 40 weeks. Infants today as young as 25 weeks gestation have a better than 40% chance of suriving, without what would be considered debilitating defects, no less, through today's medicine. Go back 100 years and think about a baby being born just over six months gestation and you decide whether you think it would have lived.
Infants born with heart defects receive operations today. Not all are successful but a darned sight more are successful than the total that would have quietly died 200 years ago.
We don't usually die of the flu today. Some do. Very few, especially as compared to generations past.
I could go on, but god. You poor people are bored enough by now. Besides, the kids are out of their bath now, which means playtime is over for JerZ.
No, actually I have perfect vision. Nearsightedness does run in the family. When I say run in the family, I mean more people have it than don't. I just didn't get those genes. I said that more people live with defects today and I was informed by another CD member that this isn't the case. Who do I believe?
If you are referring to me, I did not say that it wasn't the case. I really do not know. I gave you 3 reasons as to why it may seem so, or why, due to medical technology, it would actually be the case.
I did not definitively say that there were, or were not, more defects.
I did say that crime was going down, and you seem to have glossed over that fact.
You have contradicted yourself in your own post.
1. You say that if you have technology, it will protect you from skin cancer, and therefore you need not evolve.
2. You see a doctor frequently to check it out, even though you do have technology.
Which is it?
You are also presuming that the human progenitors needed to darken their skin or die. What about the possibility that they started dark, and as the migrated out of Africa, they lost the skin pigment because they no longer needed it?
Lets go back to your original point. You asked about how evolution would protect one from the sun. I gave you an answer, complete with a link to proof that it works.
You asked, I answered, you refuse to accept solid proof.
You're right. I am stupid and have the ability to make up my own mind. I choose not to use sunscreen (I know I'm stupid). YOU said that when they moved to Africa their skin got darker, not me. You said there were three types of "pre-humans", Mongoloids, Negroloids, and Caucasoids (I probably didn't get those exactly but you know what I mean). You claimed that as they migrated, the mongoloids eyes began to slant to protect them from the sand. You said the Negroloids skin darkened. Why did the Mongoloids eyes slant and not the Africans? The Africans had to travel through the Sahara and Kalahari deserts (both of which get extreme wind storms). And please don't accuse me of not accepting proof because I gave a likely situation that would defy that proof!
You're right. I am stupid and have the ability to make up my own mind. I choose not to use sunscreen (I know I'm stupid). YOU said that when they moved to Africa their skin got darker, not me. You said there were three types of "pre-humans", Mongoloids, Negroloids, and Caucasoids (I probably didn't get those exactly but you know what I mean). You claimed that as they migrated, the mongoloids eyes began to slant to protect them from the sand. You said the Negroloids skin darkened. Why did the Mongoloids eyes slant and not the Africans? The Africans had to travel through the Sahara and Kalahari deserts (both of which get extreme wind storms). And please don't accuse me of not accepting proof because I gave a likely situation that would defy that proof!
My question to stretch et al is when do they stop being human and become something else?
Answer: they don't
And only time and unbiased research can prove that out.
You're right. I am stupid and have the ability to make up my own mind. I choose not to use sunscreen (I know I'm stupid). YOU said that when they moved to Africa their skin got darker, not me. You said there were three types of "pre-humans", Mongoloids, Negroloids, and Caucasoids (I probably didn't get those exactly but you know what I mean). You claimed that as they migrated, the mongoloids eyes began to slant to protect them from the sand. You said the Negroloids skin darkened. Why did the Mongoloids eyes slant and not the Africans? The Africans had to travel through the Sahara and Kalahari deserts (both of which get extreme wind storms). And please don't accuse me of not accepting proof because I gave a likely situation that would defy that proof!
I did not say most of these things. I think that you are confusing me with another poster.
I did say that you should look to Africa for an evolutionary adaptation to the sun. Not more.
Very interesting thread here! Thanks for keeping it civil. There are a couple of posters who keep going off topic. Please stay on topic or create your own thread, or pm one another. Thanks!
Sorry, you are right. You didn't make the eye comment. But I have heard a couple references to the slanted eyes. It just doesn't make sense that Asians would get slanted eyes to keep sand out, and not Africans. You would think it would be the opposite because the Sahara is the harshest desert around.
I was one who brought up the epicanthan fold -- I mentioned it gave advantage in dustier and highly reflective environments. It was the combination environment of the tundra plains that are hypothesized as reason for this narrowing of the visible eye in asian populations.
The natural cycle of ice ages over the past 100K years has vastly changed the Sahara desert of Africa several times. During the height of a deep freezes, the Sahara (surprisingly) becomes a much larger desert than it is now, and when those ice ages start their 2000 year recession cycle this same area becomes quite a temperate environment. In contrast, the tundras of Asia may move north and south but widely remain unchanged, weatherwise, by the polar ice growing and shrinking. Just hypothesizing here, but I would guess Africans never had enough time to really adapt that specifically to the highly variable environment in Northern Africa.
Also, its worth noting, since adaptation is based upon random mutations, two human populations can develop entirely different adaptations to deal with with similar environmental issues. In fact, it is very unlikely to see the same mutations develop to deal with the same problem.
Just in reference to MontanGuy's earlier point about pressures on early populations of humans in Africa that caused them to migrate -- this unstable environment in Northern Africa -- especially when in a temperate period is collapsing into a desert environment at the starting of ice age cycles -- was likely a very strong motivator for people to leave Africa for Europe and Asia -- not just once, but over and over and over.
I was one who brought up the epicanthan fold -- I mentioned it gave advantage in dustier and highly reflective environments. It was the combination environment of the tundra plains that are hypothesized as reason for this narrowing of the visible eye in asian populations.
The natural cycle of ice ages over the past 100K years has vastly changed the Sahara desert of Africa several times. During the height of a deep freezes, the Sahara (surprisingly) becomes a much larger desert than it is now, and when those ice ages start their 2000 year recession cycle this same area becomes quite a temperate environment. In contrast, the tundras of Asia may move north and south but widely remain unchanged, weatherwise, by the polar ice growing and shrinking. Just hypothesizing here, but I would guess Africans never had enough time to really adapt that specifically to the highly variable environment in Northern Africa.
Also, its worth noting, since adaptation is based upon random mutations, two human populations can develop entirely different adaptations to deal with with similar environmental issues. In fact, it is very unlikely to see the same mutations develop to deal with the same problem.
Oh wow, that brings up an interesting point that two beings would most likely develope different ways to deal with the same problem. It makes perfect sense, I had just never thought about it before. My friend and I designed websites one time, they were two different ideas for the same site. They worked almost exactly the same, they just looked different, but when we compared our codes there were a lot of differences in the harder areas to design. Thanks for that, that is interesting. lol, I don't know why this is so interesting to me, it is rather obvious, but thank you.
I have read this whole thread through and it is quite interesting. I just think it's somewhat futile to try to tell somewhat who sees green they're looking at red. Maybe they're colorblind.
Anyways I just have one question that I've thought about so much: Where did the intelligence behind evolution come from?? I mean maybe this sounds silly but why are animals so beautiful?? If it was really just evolution why would nature or whatever care about what they looked like? It certainly serves no purpose for a bird to be beautifully colored. In fact I would think that if evolution was all about survival the bird would be plainly colored as to not attract attention to itself? Just a thought.
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