Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: latebind on 06/04/2009 18:30:43

Title: How are humans evolving in the 21st century?
Post by: latebind on 06/04/2009 18:30:43

As I understand it, evolution is a constant process, so it is pretty much a given that our generations are evolving right now.

I want to ask how are we evolving? Is it positive or negative evolution (devolving), and has anyone actually seen any evidence of these?

Title: How are humans evolving in the 21st century?
Post by: Don_1 on 07/04/2009 09:49:55

Evolutionary change is far too slow and subtle to be noticeable. We could no more expect to see any difference in the evolution of man than we would in say lions or elephants.

It has been suggested that human evolution has stopped. I don't think this is quite true. But it may be that it has slowed down or changed its nature.

One of the key elements of natural selection is in the choice of mating partner. Females will accept or reject the advances of a courting male dependant on his suitability. This may be his colouration, dance, size, song, strength etc. or the the males will fight for the right to mate with a number of females. Only the strongest, fittest, healthiest males will earn the right to mate. In other words, only the males carrying the most successful genes will get to pass them on.

Humans would have applied the same criteria in their earlier history, but for some time now the choice of mating partner has been more related to appearance, personality and even wealth than to health, strength and fitness.

If the above is true, then humans are not weeding out the unhealthy and unfit traits which are passed on through genetics. Perhaps this is the reason for the increase in the number of people suffering from hereditary linked problems such as asthma and diabetes. If we were choosing mating partners in the same way as the rest of the animal kingdom, individuals with such problems would not be chosen as prime mating material.

Title: How are humans evolving in the 21st century?
Post by: Variola on 07/04/2009 11:33:21

Good post Don.  [:)]

Quote

If the above is true, then humans are not weeding out the unhealthy and unfit traits which are passed on through genetics. Perhaps this is the reason for the increase in the number of people suffering from hereditary linked problems such as asthma and diabetes. If we were choosing mating partners in the same way as the rest of the animal kingdom, individuals with such problems would not be chosen as prime mating material.

Indeed people suffering from Asthma or diabetes would have died in past times, same as people with cancer, epilepsy etc. Therefore their genetics input to the pool would have been significantly reduced.
In terms of our understanding of the world, and the technology we have at our disposal today, we have evolved increadiably fast in comparison to a thousand years ago, but physically it is much much slower and almost impossible to see in the timescale that we measure from.

Title: How are humans evolving in the 21st century?
Post by: latebind on 07/04/2009 19:08:32

BTW I believe I put this in the wrong post, sorry for any inconvenience. It should have been inside [ Plant Sciences, Zoology & Evolution ]