Natural Selection and inanimate matter

revo74

Was the evolutionary principle of natural selection at work on the earth before animate matter(life) emerged? Inanimate chemicals replicated before R/DNA and the first living cell. Did natural selection apply to these chemical molecules?

If the answer is yes, is it just a hypothesis or has there been a scientific theory in chemistry that incorporates natural selection of non-living organisms?

Please elaborate. Thanks!

mishrashubham

If you have a self replicating entity, you can have selection. In theory there could have been replicating molecules before RNA or DNA but there actually were any such molecules is completely unknown. So no leads there.

It depends on what you consider animate or inanimate; you could look at prions may be? These are infectious protein fold states. They can go through selection, just like your regular microbial pathogens do.
http://www.ncbi.nlm.nih.gov/pubmed/20422111

bobze

Its important to remember that we define life for our purposes. NS doesn't really care if something is alive or not. For example if you ask most biologists they will tell you viruses are non-living, because we define them to be that way. That doesn't stop NS from acting on them. In a single person with HCV there can be hundreds of quasispecies of virus present. Its what makes things like vaccines to HCV, HIV, influenza etc so hard to do.


What selection does care about is really only 4 basic things--The same 4 that Darwin noticed all those years ago. It cares about; variation, heritable variation, environments that are finite and differential survival and reproduction.

From the start then; variation just means that every individual in a population is not identical--that there is variation between them. Some of that variation has to be heritable--that is passed on from parent to offspring. These individuals have to live in an environment of finite resources, if all resource requirements are met then there is no competition and thus no selection. Lastly, reproduction and survival are not equiprobable events for each member of a population. Because of variation (and limited resources) some individuals will have higher (or lower) chances to survive and/or reproduce.

With those met, "something" (whether we define it as alive or not) is capable of evolution by natural selection. Because we impose our definition of life on the natural world--we create an artificial boundary between "living" and "not-living" that doesn't really exist in nature.

Humans love black and white, while Nature thrives on shades of gray.

mishrashubham

Exactly; a very important point.