It should be pointed out that there's an evolutionary pay-off between length of generation and speed of evolution. Turtles that live beyond 100 have got to that point because they don't need to evolve as quickly as bacteria.
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Originally Posted by yodachoda
The reason we humans are so diverse is because we don't have natural selection acting strongly on us. Weak humans (if we were as intelligent as monkeys and living in the forest) would die by natural selection. They would get sick early in life and die. But we humans put them in hospitals so they don't die, and they spread their genes on.
This is the reason **** sapiens are diverse. Some of us have black hair, some blonde, some brown skin, some peach, some fat, some slender, ect. In other animals, in nature, individuals in their species look mostly the same because there have been extremely powerful natural selection forces shaping them to the optimal phenotype.
Another example is dogs. There's huge genetic diversity in dogs because we humans will care for a poodle or pug when it would die if it were in nature.
So since humans genes are so diverse, there's more genetic shuffling possible than in the coelecanths, which is why I said we are slowly evolving while they are not evolving.
Human beings have different physical characteristics because we have evolved to be adaptable to our surroundings, not because we preserve the dying. The dying usually don't get to reproduce anyway, and if they do, it's because they're healthy enough - that's just how society works. We've only had hospitals and decent hygiene standards for a very short amount of time, yet evolution hasn't seen fit to get rid of down syndrome
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Originally Posted by yodachoda
Yeah that sounds right to me. We are constantly evolving. Take my colorblind example. What if instead of just one colorblind person dying, all of them died. In the future, no humans will have colorblindness. You can't disagree that that is evolution, right? It might seem like "no big deal". So what, colorblindness isn't important. Or, so what, so two people died on the planet, they have such a tiny effect on the gene pool. But these types of changes, occuring one after the other for billions of years are exactly what have turned bacteria to humans.
Hopefully you're just trying to make a point and aren't trying to claim something that even I, untrained in biology beyond the age of 16, can see - that genes aren't always active, so killing off all the colourblind people in the world doesn't kill off colourblindness. I mean, that's just way too obvious, right?