macroevolution has effectively stopped in humans

Author: n8nrgmi

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n8nrgmi
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evolution from species to species occurs when the environment causes some animals to die out, and only the survirors with the right genes live on to pass on their genes. the thing is, with humans, humans have adapted their environment to themselves. so, there won't be major evolution occurring. maybe things like lactose intolerance will continue to evolve, and other micro evolutions. but, nothing major should be in our future unless there are drastic changes to our environment. 
oromagi
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Well, micro-evolutions is a relative notion that keeps us  from having to explain many recent adaptations like blue eyes or high altitude tolerance or malaria resistance or smaller craniums.  I don’t buy the idea that humans control our environment at least not until we can tame a hurricane or reverse global warming    I assume humans will transit space and colonize other planets in the next few thousand years or else fail as a species but space and exoplanets are incredibly challenging environment that make Antarctica and the Marianas trench look like Edens. Right now our skeletons barely tolerate weightlessness and gamma ray radiation kills us in horrifyingly low doses but we will certainly adapt to those challenges or perish
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some organisms are quite good at surviving
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@n8nrgmi
It seems odd to me to say macro-evolution. What about the evolution of a species that makes it different from a thousand tiny steps like eye color and lactose tolerance? Eventually, you will get a new species from "micro-evolution," so the prefixes are useless except perhaps to indicate a period in which something is happening.

As a result, I disagree that humans have effectively stopped "macro-evolution." It feels as though humans have hardly changed at all since the beginning of civilization, but in the terms of specific (relating to a species) evolution, that isn't a long time. There are indeed fewer physical factors that help promote gene fitness today, with a large proportion of the world's human population enjoying stable diets and environments, but there are other factors to consider.

Evolution is no longer the only force for specific (once again, meaning "relating to a species") change on Earth. Humans have been performing artificial selection for tens of thousands of years, in the domestication of plants and animals, and more recently in the form of GMOs. It is probably only a matter of time before humans artificially alter themselves on a species-wide scale. I hesitate to use the word eugenics because it's historically associated with racism and is mainly conceived to operate through selective breeding. Transhumanism largely favors body augmentation through robotics as opposed to gene manipulation but is a lot closer to what I'm talking about.

tl;dr
"Macro-evolution" is still taking place, but technological advancements will enable humanity to control their own evolution long before it has a large effect.
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@oromagi
We have changed our environment significantly just by the tech we have to heat and air condition and humidify and de-humidify our interiors, and, to an extent, even our exteriors. But, evolution is more than adaptation to environment, let alone facial variations. What's an appendix for? Tonsils? Why are both of my little toes turned on axis outward 90 degrees? Why is my voice like that of God [or James Earl Jones] when the rest in my immediate family have timid voices?
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@n8nrgmi
As long as there are some random mutations in the human population, and there aren't any factors that would prevent those with the mutations from reproducing, there won't be any stop to macroevolution. Macroevolution is simply the aggregate of many microevolutions.
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@PressF4Respect
mutation is the driving force for evolution, but historically that has always been determined by natural selection, where some species dies and doesn't live to reproduce. if there's no on dying to focus on the mutations humans have, there's no reason to think the mutations will prevail in the population. what reason do you have to think it will?  a mutation with no survival of the fittest, is just background noise.