On humans, those with "poor" traits (for example, bad eyesight) would have been killed or died at a young age. Thus, only those with better genes (like those who could actually see well) would reproduce.
However, technology allows those with bad genes to have a higher chance of reproducing and passing those genes on to other humans. Needing glasses or contact lenses may not seem like a big deal, but we also allow things like diabetes, heart conditions, and the like to "spread" to more people.
Fortunately, we are now reaching the stage of being able to artificially improve ourselves genetically. Hopefully, people won't mess with stupid things like eye color and instead only touch important things like eyesight.
Please Note: I am not saying that people with any of the problems I listed are inferior, just genetically inferior.
I disagree. I've noticed that people with the following qualities still tend to be more likely to get married and raise children than those who lack them:
As long as people continue to find the above traits appealing in members of the opposite sex, natural selection will continue to do its thing. There are exceptions, of course, but there always are; its the general trend that concerns Darwinism, not the specific beaters of the odds.
Ok, so I may be insensitive, but this is a prime example of Better Darwinism through Technology.
Obesity is a good example. Suppose that women found severly overweight men very attractive. Women all over the world would search for these overweight men, and try to have sex with them. These men would sleep with at least a thousand women a year. In this scenario, wouldn't you agree that fat men would become more prevalent (assuming obesity is genetic)? But doesn't obesity cause heart disease, etc. which is bad for survival? This is to illustrate that natural selection does not necessarily lead to more desirable traits. The reason natural selection usually does lead to more desirable traits, and why the above example isn't likely to happen, is because there is no reason for women to be especially attracted to fat men, because that will decrease their children's odds of survival, which would diminish the attraction to obese men as a trait in the gene pool. The only way that this scenario could lead to increased survival is if all women were initially attracted to fat men either because it used to increase the liklihood of survival, or because it happened suddenly, in an "outbreak."
Another example are midgets dogs. Most animals that are born as a dwarf are killed very early on. However dogs like chihuahuas or toy poodles have a very high survival rate? Why? Because they're cute. Sure, they may not be the best physical specimen designed for survival, but there are other factors involved too.
Natural Selection is not a magical or mystical force. It is a principle. It applies outside of biology as well.
Natural selection DOES only take place when individuals that are less suited to their environment are removed from the gene pool.
No, this isn't how things work. The population as a whole does not drastically shift behaviors. If dominant trait X begins to develop in a population, and the affect of this trait is that people with trait X need to be cared for by people without trait X, some people without trait X will care for them, and some won't. Suppose we assign the label "trait Y" to the gene that makes you care for those with trait X.
Yes. If trait Y (caring for people with trait X) is a survival advantage, the people with trait Y will come to dominate the gene pool. If it isn't, they will be gradually removed, as will the people with trait X because they don't have anyone to care for them.
No, this isn't how things work either. Environments do not have a specific capacity, beyond which massive dieoffs suddenly occur. If the population begins to exceed the environment's ability to sustain it, resources will become scarce. Suppose food becomes scarce. People will begin to die from hunger until the population has been reduced below the level of the environment's ability to support them. The ones that die will depend on which genes are better suited to deal with the situation, thus natural selection.
Yes. But this will only happen if trait X allows those with it to better survive in the environment. If trait X is impotence or total brain death, it will probably never become dominant in the population.
Yes. Trait Y will eventually be wiped out, as will trait X, if people with those two traits are less likely to reproduce.
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