Is modern medicine disrupting natural selection?

Question

Advances in modern medicine have begun to eradicate disease and improve the chances of survival and thus procreation for humans. Will this slow down the evolutionary process?

Answer 1

This is definitely the case.

Evolution essentially means that those best adapted to their environment will survive. This is obviously seriously slowed down when a species develops the ability to quite drastically alter it's own environment, as well as of course prevent or treat the negative genetic factors that would lead to death in an unsupported environment.

There is still evidence that human beings have been evolving in recent times, but the more control we have over our own bodies and the more control we have over our environment the slower we will evolve.

Answer 2

I think there are some misconceptions regarding evolution and natural selection.

You ask whether ."..will slow down the evolution process". This would imply that evolution in biology is the same as progress to something better. You should think of evolution merely as change (not towards the better or worse). The driving forces are factors which have an impact on the survival and procreation of individuals within the population of a species. So no matter what, we evolve;the only variable is the direction of evolution.

Natural selection is also mis-interpreted lots of times.
We have reached a point where the influence of man on nature is too great and thus we should be speaking about selection in general, since some selection pressures on all organisms have been created/imposed by man. Even something as simple as agriculture violates "natural" selection: man provides energy, materials and protection to sustain a local ecosystem where a specific plant dominates over stronger organisms like weeds and pests and that would never reach such a state under "natural" conditions.


Medicine is not the only factor affecting human evolution..
Think about the great pressure imposed by all the different types of pollution (chemical, radiation, light, noise, etc). In fact due to the greater exposure to chemicals and radiation the rate of cancers has increased which also means an increase in mutagenesis. Thus in theory one could say that we are actually increasing the rate of evolution (but what are we evolving to?)

Furthermore, the significance of a selection pressure on evolution depends on its intensity and the time period that it is applied. For example an abrupt but great natural catastrophe
could wipe out most of the indiiduals of a population. The evolution of that species will depend on the survivors, which could be saved by pure luck and not because of a specific trait.

Development of medicine certainly relieves several selection pressures and has a long lasting effect. However there a lot of different selection pressures still acting so it is not straightforward to determine the exact path of evolution.
For instance, the fact that a person has more chances to survive doesn't necessarily mean that he/she will have more offspring or that his/her offspring will be more successful in the selection game. None-the-less having the means to overcome various selective obstacles will change the path of evolution to a degree.

Answer 3

None of those factors (or any other factors) can negate selection. They simply alter the selection pressures. There will always be variations that have better reproductive success than other variations. That is selection in action. For instance, when wolves were being turned into dogs by human selection, cuteness, attentiveness to human faces and submission to human leadership became new and powerful selection pressures for the evolution of dogs. This represents a very large change in the normal selection pressures for wolves. -- Regards, John Popelish

Answer 4

YES modern medicine is lettign the weak survive makign humans as a whole weaker and weaker. altho the evolution wont really stop but it will be slowed conciderably. Ive thought of this in the past and it saddens me to know that as tiem goes on we will become weaker and weaker and are relience on more and more technoldgy to survive will increase to the point where humans are no longer self substainable without outside medical help. Eventually humans will become weak and fragile and we will have to rely on other forms of technology like mechanical exosuits and with other systems literally isntalled and built into us to survive effectivly.

Answer 5

I don't think we could answer that question. The process of evolution occurs too slowly for us to take a good look at our own species; while trends such as narrowing hips in women, larger rears, and larger heads have been noted as childbirth has become safer, and disease has increased because less die from it, those trends don't say anything for the whole species.

Answer 6

most definitely.

thanks to advances in technology, just about anyone can extend their lifespan for years longer than our ancestors. Even weak sickly children with horrible illnesses can be kept alive for years on life support and/or certain medications.

The more weak people that are kept alive, the more they will reproduce and create further weak generations. It often seems it is the unintelligent or particularly unskilled people that seem to have more children anyways.

Evolution is screwed.

Answer 7

look around i believe that we have actually deevolutionized ourselves...those advances u speak of have only wiped out the weak diseases, 20 yrs ago we did not have pneumonias that actually digested lung tissue, or staph infections that can only be erradicated with near leathal levels of vancomycian...ignorant uses of antibotics by physicans who are only interested in moola can condem us all to an early death...except for the upper classes who can afford to keep on living at the restof the worlds expense

Answer 8

I've often pondered this same question. I think yes, it will slow the evolutionary process.

Answer 9

yes many that would die from being weak or mentally handicapped to extreme live on with our wonderful medical technologys the way they are.