lobstertrap

Okay, I'm beginning to believe the idea of "evolution." I've never really cared about it up to now, but I thought I'd investigate it and it sounds true enough for me.

Now, with that said...

In millions of years to come, does that me that we as humans now will evolve into even more advanced creatures? Maybe use more of our brain...etc?

theyeti

In millions of years we will definitely be different than we are now, assuming that the we don't go extinct. As for "advanced", evolution doesn't necessarily result in more advanced (assuming you mean complex) creatures. Quite often, creatures lose certain features as they evolve. Cave fish, for example, lose their eye site. But human beings may become more complex, or they may not.

There has of course been a general trend towards greater complexity since the origin of life, but it is a matter of debate as to why this is. Some argue that it's simply a "drunkard's walk" from an initial wall of complexity. In other words, organisms gain or lose complexity at random, and since there is a minimal threshold of complexity, everything is some random distance above that threshold -- we just happen to be at the high end.

The other view, which I ascribe to, is that complexity is selected for in dynamic environments with many interacting organisms. Thus, complexity has increased over time because more complex species are more likely to survive and leave descendants. However, it's probably much easier for a species to lose complexity in the short term, like a cave fish does. It's just that these species are probably not the ones that will be the ancestors of future life. So humans may become smarter, or we may become dumber, and in either case we may go extinct. There's just no way to predict that sort of thing, just like there's no way to predict American history 500 years from now.

BTW, the idea that we only use 5% of our brain or whatever is an urban myth.

theyeti

Doubting Didymus

It is not really possible to extrapolate evolution into the future, as there is no momentum. An evolutionary trend can stop dead in its tracks, and often massive changes in the environment mean that natural selection can start to favour completely different characteristics in just a short time.

I have recently read about an excellent example of this in the elephant population in north africa. In the past, natural selection favoured elephants with big tusks, both for attaining food and for fighting off other animals. This meant that any elephant with bigger tusks was a highly successful elephant.

Recently however, a massive environmental change completely reversed this trend. This predatorial environmental change was poaching.

Suddenly, elephants were being killed for their tusks. Whole populations of elephants were having every big tusked individual removed. Immediately, the evolutionary trend in tusks did a complete about face.

It should be noted that previous to heavy poaching, the elephant population contained a small percentage of mutant individuals whose only difference from the rest of the population was that they had no tusks. Under 1% of elephants had this mutation. Now, with natural selection suddenly on their side, that proportion is a whopping 40%, and poachers are having a hard time finding an animal with decent tusks. The elephant population is actually recovering its numbers because of this phenomenon, and poachers are going out of work, according to an article in (I think) national geographic. (Australian).

So, it is hard or impossible to predict the future course of evolution. However, as long as selection pressures favour intelligent humans over stupid ones, we will see that characteristic enhanced over (a great deal of) time.

In a quick response to your last sentence, you should be aware that evolution does not specifically favour increasing complexity, unless that complexity is a survival advantage. Also, we already use 100% of our brain (the 10% thing is a myth). To become more intelligent, we would need a larger, more efficient, or more complex brain.

lobstertrap

You sure about that? My mother has her Ph.D in nursing, and one of her nursing books she uses for research at her job plainly states we only use about 14% of our brain, and that when we learn to use the rest of it, who knows what we could do (lift objects with our minds, be ungodly smart, etc).

Maybe the book's lying, I dunno, obviously the publisher believed the author.

Kevin Dorner

<a href="http://www.snopes.com/science/stats/10percnt.htm" target="_blank">The Ten-Percent Myth</a>

Doubting Didymus

Unfortunately there are a heck of a lot of books that get published but just don't pass muster. The 14% thing is definitely a myth. This is well documented and I will supply links if you like.

A good way to test this is to shoot a person in the head. If only one in ten people gets brain damage then it might be true. (This is not really a joke. The fact that brain damage occurs when even the slightest damage is incurred is good evidence that we use all of our brain.) There is also plentiful evidence from brainwave monitoring.

However, it may not be the fault of either the author or the publisher, because things like this get absorbed into common knowliedge. Both the author and the publisher may have been thinking 'of course that's true, everyone knows that'. However, I would be concerned if it was in a genuine medical textbook.

Doubting Didymus

Ah! I see Kevin has already published that link.

Starboy

Greetings lobstertrap,

The only selection pressure that I can see is for looks. As far as I can tell, intelligence doesn’t appear to be high on the list.

Starboy

Doubting Didymus

You assume that mate selection is the only selection pressure. Survival advantage is still involved, but like I said earlier, it is nearly impossible to predict the course of unguided evolution. Certainly if we were allowed to selectively breed humans, evolution would be able to do nearly anything.

Mageth

The only selection pressure that I can see is for looks.

&lt;looks around&gt;

You sure about that?