Are we not evolving before our eyes?

Originally posted by Praetorius

Wrong. Micro-evolution is adaptation within the existing genetic code. Macro-evolution requires the actual addition of new information/new genetic development, not changing expression of the existing genetic code. Scientists have never been able to point to a single mutation increasing the information content of genetic code.

Here is an example I found on this website: www.gate.net...

12% (3 out of 26) random mutations in a strain of bacteria improved fitness in a particular environment.

Contribution of individual random mutations to genotype-by-environment interactions in Escherichia coli
Susanna K. Remold* and Richard E. Lenski

Center for Microbial Ecology, Michigan State University, East Lansing, MI 48824

Edited by M. T. Clegg, University of California, Riverside, CA, and approved July 30, 2001 (received for review March 22, 2001)

Numerous studies have shown genotype-by-environment (G×E) interactions for traits related to organismal fitness. However, the genetic architecture of the interaction is usually unknown because these studies used genotypes that differ from one another by many unknown mutations. These mutations were also present as standing variation in populations and hence had been subject to prior selection. Based on such studies, it is therefore impossible to say what fraction of new, random mutations contributes to G×E interactions. In this study, we measured the fitness in four environments of 26 genotypes of Escherichia coli, each containing a single random insertion mutation. Fitness was measured relative to their common progenitor, which had evolved on glucose at 37°C for the preceding 10,000 generations. The four assay environments differed in limiting resource and temperature (glucose, 28°C; maltose, 28°C; glucose, 37°C; and maltose, 37°C). A highly significant interaction between mutation and resource was found. In contrast, there was no interaction involving temperature. The resource interaction reflected much higher among mutation variation for fitness in maltose than in glucose. At least 11 mutations (42%) contributed to this G×E interaction through their differential fitness effects across resources. Beneficial mutations are generally thought to be rare but, surprisingly, at least three mutations (12%) significantly improved fitness in maltose, a resource novel to the progenitor. More generally, our findings demonstrate that G×E interactions can be quite common, even for genotypes that differ by only one mutation and in environments differing by only a single factor.

reply to post by Hydroman


That was an interesting read.

IMO, I think the success rate of mutations must vary greatly for simple organism vs complex organisms.

what do you know about that?

reply to post by mwuhi


Totally agree, all dumbed down in the media, the professions are all undervalued, no respect for others anymore.
its devolution too in my opinion, we appear to be going backwards.

Really hoping 2012 does not see even more but there is a chance that it will get that bad, shtf THEN we get some evolution and change, but its an awful way to evolve...and history has taught us that the most terrible wars, disasters etc do not seem to change our destructive nature but ....maybe this time eh?

what selective pressures effect civilized humans?

i cant think of any.

About one in every 100 cell divistions will result in a small error. Most of the time these errors are unnoticable and won't effect you. The number would get higher the more you are exposed to harmful substances (which are everywhere lol). These errors can cause many of the diseases that people get.

I'm surprised so many people think that our evolution has stopped! I think that it has and will continue to increase exponentially. Unfortunately not always for the better. Not long ago there were articles springing up everywhere about the latest trend in human evolution. The diminishing brain size...

www.npr.org...

I would assume that this diminishing size is due to the lack of personal reliance. The same thing has been shown to happen in animals once they become domesticated. We don't need to search for our own food, we can just go to a restaurant and someone else can prepare it for us...

Evolution is a one way street, devolution is a fabricated term that has no real meaning.

People get hung up on evolution because of their own arrogance, suggesting higher and lower forms, and more evolved or less evolved.

Evolution is a simple concept to grasp, (not so simple to prove admitedly) it is simply the changes that occur to a living organism in response to external stimuli.

We will never "devolve" back to our original primate ancestor, we may however evolve to a creature that is more similar in appearance and mental accuity if the correct external stimuli exists.

And its quite possible to evolve into remarkably different looking creatures (dogs are the usual model here) and still be the same species.

Speciation is the point at which creatures that shared an ancestor could no longer produce viable offspring. This is another point where people get confused about evolution.

Donkeys and horses once, possibly quite recently in evolutionary terms, shared a common, horse like ancestor. Currently horses and donkeys can produce offspring (mule) but these are sterile and unable to reproduce. This is an example of speciation in progress, which in turn is a result of evolution. At the point when donkeys and horse can no loger produce a mule, they will be completly different species and not merely different breeds of the same animal. (actualy, I think they may already be classd as different species but will err on the side of cant be bothered to google it)

In conclusion. once you understand that evolution has no goal, no end game and no final solution, that it is purely the mechanism by which living organisms survive and prosper, or fail and go extinct in any given environment, it all becomes crystal clear.

P.S. its realy quite enlightening when you realise that evey organism on the planet is exactly as evolved as you...worms, slugs, elephants and eggplants.