Has our BIOLOGICAL EVOLUTION ended?

[charles brough]

Why not? We don't need biological evolution any more! Some say we are the same creature who emerged some 195,000 years ago. However, for the next 160,000 years, our tool-weapon technology was the same primitive type had by the Neanderthals. So, some biological evolution was still going on.

But 40,000 years ago we suddenly started to evolve "culture" at a much faster rate. That is, we ceased to any longer need biological evolution because a process of social evolution had begun. What did it was the neurological, speech/hearing refinements that enabled us to bond into much larger groups than the hunting/gathering groups we had biologically evolved in. We learned to adopt world-view belief systems that could bind us into societies.

For the last some 195,000 years, we did evolved a slightly smaller brain case, thinner leg bones and immune system changes that help us fight influenza, but since the biological evolution refinement that enabled the 40,000 year ago take off in social evolution, we are all "us" and the same. We are different from all other Hominids and all other life. We are unique. Other species have all the traits we have but always only more primitive.

This should be emphasized, because the biggest problem we have with the old religions over the evolution-creation fuss is that people need to know just who "we" are. Every religion has some sort of an answer to that because every society needs to agree on who "we" are or it cannot be a society. We are not an evolutionary blur and the Neanderthal is not one of us---even though anthropologists always focus on putting more distance from their description of him and that of the comic book caveman!

Anyone interested in social evolution should take a look atathttp://atheistic-science.com

charles

[Pyrotex]

The answer is NO. Biological evolution cannot end.

The reason is simple. We are still engaging in sex and having offspring. That's it.

The process of sexual reproduction always selects (randomly) from the genes of both the father and mother to produce an offspring. Sexual reproduction does not and cannot "freeze" in any biological way and stop creating new genetic combinations and permutations.

And some of those combinations and permutations will always make the offspring less (or more) likely to survive to maturity and to procreate. And that's evolution.

Now, this process can be speeded up by having the environment become very hostile. And by "environment" for Humans, I also include social and cultural factors, as well as physical and ecological factors--ALL factors. Examples: war, economic collapse, over-population, starvation, epidemic diseases.

And this process can be slowed down by "good times" when even dimwits, the socially inept, thugs, kids in wheelchairs, diabetics, fools, some neoconservatives and the financially challenged are enabled to survive and procreate as easily as anyone else. But good times do not last forever; not in any Civilization.

But fast or slow, the process of biological evolution continues. It is "built in" to the very design of DNA sexual reproduction. You cannot make it go away.

[Nitack]

In addition to what Pyro said, I would like to point out that our tool-weapon technology has created new obstacles that have a real impact on our biological well being. Perhaps it will not be as visible as previous evolutionary changes, but we will see the internal workings of man evolve.

Our advanced farming techniques have created an overabundance of available Calories/food. This has led to skyrocketing obesity rates and the related health conditions. There are couples who are quite frankly too fat to have children. That is evolution snuffing out their unique DNA. What we may end up seeing is that the human race evolves in such a way that individuals with higher natural metabolisms or with a particular learned behavior passed on by their parents end up thriving where the more rotund factions of humanity slowly die off from their own sloth and lack of self control.

Additionally, we are still releasing quite a lot of artificial, highly-toxic, slowly decomposing substances into the atmosphere of our planet every day. These substances can last thousands of years before breaking down. We breath all of that crap in, it will eventually cause health problems. I am pretty sure we will see biological evolution along the lines of people whose bodies are better able to cope with those toxins.

Finally, there are still plenty of pathogens out there that effect our world. As we are finding out, those organisms are still evolving in order to survive and becoming more and more resistant to our efforts to harm them. Bacteria that are resistant to all but the newest and most powerful antibiotics, virus' that are resistant to vaccine creation (AIDS is one such virus). The competition between our species and those species will continually force humans to evolve in order to mitigate the abilities of those new strains of bacteria and virus'.

[max4236]

Sorry I haven't made any offspring yet..

[Turtle]

I watched a show on PBS the other night and part of it was this guy who studied baboons and stress. He lived with them because he needed to collect blood samples continuously, and studied one particular troop. Like us, the biggest most aggressive baboons had their way with all the women and beat the hell out of any males they cared too. Anyway, people moved into the area and the baboons started feeding in their dump and only the bullys got any, but there was TB in the dump and all, and only, the bullies died.

What was unexpected though was that no less aggressive males took over with the brutality, rather the entire troop adopted, and maintained, a group behavior sans the brutality. New males coming in from the outside adopted the more passive behavior within 6 months.

What continues to evolve is our accumulated wisdom.

PS: >> http://www.pbs.org/nights/blog/2008/..._a_killer.html

[Kayra]

I think that technology will shortly (within 1 generation) remove the last vestiges of our environment affecting our evolution.

Pyro is correct though (nice shot at neoconservatives there ), so long as we breed, we evolve. What will drive the evolution if the environment is no longer the stressor? I would have to say societal, social, or religious preference.

[Donk]

Punctuated Equilibrium
When a species has it easy, mutations accumulate unnoticed. The species gains a lot of variety. Then, a thousand or a million years down the line, the environment changes. Those variants best fitted to the new circumstances start to dominate the gene pool. If the change is extreme enough, it leads to a die-back and potentially a whole new species.

We've had it easy for several thousand years now, but as a species we're still quite young. You think we'll still look like this in ten million years?

[charles brough]

I see that Protex and Nitack have raised serious "no!"s

Have all those examples of natural selection you mention altered our genetic code? Do you have it separated in your minds what is genetic and what is epigenetic? How do those processes you describe determine the rise and fall of civilizations and account for the growth of the human cultural heritage in the last 40,000 years?

What I find is that all of the social and natural sciences are focused on biological evolution as being the explanation for all our change. The reason is that they have no other explanation. The fact that biological evolution does not explain human "progress" during that time is dismissed and avoided.

The latest information I have is that in the last 195,000 years, we have changed biologically only in having a slightly smaller brain case, thinner legs and better immunity to influenza. Do you know that even the speech center that is evident in the cranial case of Ancient Sapeins is also evident in the Homo Habilus crania?

Social evolution accounts for what we call "progress," but others are reluctant to deal with it because they associate it only with Social Darwinism. That is a big mistake! It is not races that are the entities which compete to survive! It is mainstream religions. They serve a functional purpose of binding us into much larger groups than the 40-member hunting-gathering groups we evolved in. (see: the Atheistic Science Institute - home page )

charles

[Ganoderma]

to me, evolution means change in the specie/group/person. so unless we are jsut clones, i don't think we can stop evolving.....we could possibly start evolving for the worse physically i suppose. i wonder if we are all going to have squinty eyes and hunched backs from computers.....its not far off.

[Boerseun]

Unfortunately, is not as easy as "Evolution has stopped" or "Evolution has not stopped".

Fact is, in nature, species evolve to suit the demands of an ever-changing environment. The human species is the first species to do it ass-backwards: We have tamed our environment, and change the environment to suit our desires and purposes. The environment is evolving to suit us: Those "environments" not fit to human tastes are utterly destroyed and changed to whatever humans want it to be. Look at cities, parks, etc. Our cavalier attitude towards such (currently) pie-in-the-sky concepts such as "terraforming" other planets, is merely more of the same. The planets better suit us, or we will make them suit us.

Humans, on the other hand, evolved into a relatively blind alley if you consider our growing dependence on technology. Each and every generation does, indeed, differ from the previous generation in a random way - the genetic variation is simply a concatenation of the previous set: The fact that they are around after four billion years of survival is enough for the gods of genetics to include it in the new set - and add a bit of random variations into the mix. But this is exactly where the problem lies. Nowadays, for whatever reasons, we do our best to keep every single infant fresh out the oven alive. Kids born with heart defects which would have been a death sentence a mere few years ago are now operated upon in vitro, and they end up surviving, and procreating again another generation down the line, with their spouses (who were originally sexually attracted to the individual) having no idea about the buck teeth, heart problems, kidney issues, and general medical unfitness of the individual. Their defective genes goes to the next generation. And so on and so forth.

Mutations are random, and are very unlikely to be beneficial. Pulling a figure from thin air, we can say that 99.99% of mutations are detrimental to the individual. But with our medical technology in such an advanced state, and with our misplaced altruism, we will make sure that the baby born with everything wrong you can imagine, will survive; we will alter her hare lip, we will operate on her defunct heart before she's even born, we will straighten her teeth, we will allow her to alter her rather hideous appearance through cosmetic surgery, turning her from the ugliest girl on the block to the hottest chick with the tightest butt and most awesome boobs ever (all secondary sexual features that influences the choice made by her suitors as to procreation - Hey, that girl will make awesome babies!, your subconscious will cry out).

And then you end up procreating with the girl, and you cannot for the life of you understand why all your kids need intensive medical care just to survive their first few months on planet Earth. If Armageddon comes to this planet, and our technology fail, it will not be the West who survives. It will be the most primitive of nations in the so-called Third World who don't have access to (and grew dependent on) advanced medical care, who will inherit the earth. The affluent nations will disappear in one generation because they've grown genetically dependent on high technology.

But I digress. Evolution can't stop, like Pyro said. But evolution in the Darwinian sense, "Survival of the Fittest", have stopped dead in its tracks. Because we are spending an enormous amount of resources to ensure the survival of the least fit, to have them spread their defunct genes a generation down the line.

I personally think, though, that at a larger level, humans have transpired the bonds of environmentally driven evolution. The environment is humanity's bitch - it better change to suit us, or be damned. Human evolution is driven entirely by falling for sexual adverts (big boobs, tight buns, straight teeth, whatever popular culture will have you believe is desirable), but like we've seen in my example above, human sexual adverts are not always to be believed, and may make up a strong case for false marketing when the babies you have with the most awesomely attractive woman in the world turns out to be the most heinous, ugliest babies in existence, with no business pretending that they're "fit" for this or any other environment.