Why not?

[Stella_Omega]

"The genetic variation in Homo sapiens is exceedingly small, less than that on one subspecies of chimpanzee . . ."

Yes, but we still display enough variances that for most diseases, there are immune populations -- we even have a very few people that seem to be immune to HIV, for instance.

 

[rgraham666]

As well Steven Jay Gould, who is, was, very well respected in his field, theorizing (it's all a theory in this as far as I know) that we do make sudden evolutionary jumps, as others also have stated this belief. Some of the archeological record seems to bear this out as a possibility too.

Punctuated equilibrium is what it's called. Basically it says evolution happens rather quickly, in a couple of thousand years, rather than millions.

A species is adapted to its environment. As long as the environment stays the same the species has no reason to change. But when the environment does change the species adapts quickly. I'm not saying a big jump, from dinosaurs to birds say. But from donkey to horse, although that's a pretty big jump in evolutionary terms.

There are living examples of this.

There is a lake south of Lake Victoria. It used to be a part of Lake Victoria until a sandbar rose to cut it off three thousand years ago. There are three species of fish that live in that lake, and nowhere else in the world. They are similar to fish in Lake Victoria, but they are separate species that can't mate with the ones they descended from.

 

[mismused]

delete

 

[Stella_Omega]

Well, my feeling is pretty much that we will only evolve forward-- as we define forward and as you are defining forward---- if we do it deliberately, and we don't think humans should be deliberately bred... Sentience keeps getting in the way!

 

[mismused]

delete

 

[Jenny_Jackson]

The only way I intended to define forward, if I did, was as evolution might, or has done it.

Let me get more specific on some of these none physical items.

What drives their evolution? They've obviously evolved. Is it our knowledge? Has Nature built in an evolutionary trait into knowledge stipulating, for instance, that as we learn, our ability to learn changes, or will change? And if so, to what end, if any?

It is obvious, or so some say, that physically, we do change, and for a purpose. In the female, we are different from others. It is the female that has the "plumage," if you will. And in that, it has been said that females are "striving" to be more beautiful, more comely. For instance breasts, which seem to have no function other than to attract (glands don't need breast size to provide milk).

So what is it with consciousness as exhibited by us, and our growth from the past? To what in the future? Any extrapolations?

We like to think of evolution as linear. In fact that's the way I was taught in college. However, that notion is just wrong. Evolution seems to happen in jumps followed by long peiiods of stability. The question you are really trying to ask is: Why the jumps? Why do we even need to evolve?

The answer is both simplistic and hard. The simplistic answer is: Animals evolove because they gain or possess an unused trait that makes them more likely to survive within a given environment long enough to reproduce and pass that trait along to their offspring. That's right from the textbook.

But there is a bigger answer contained in the genome. We have traits that we never either use or even suspect. Furthermore, a small change in a single ameno acid at the right place with trigger a new trait. And these changes do occur more often than we think. They come from background radiation (such as Radon), errors in the formation of the zygot and even from the occasional cosmic ray from outer space. If you look around, you will see these trait variances, usually the negative changes - Mongoloidism for instance.

In their own right these changes are neither good nor bad and only become veiwed positively or negatively as the animal reacts with its enironment. A two-legged naked ape with no claws, not very fast and teeth designed to grind vegitation isn't very likely to survive on an open veld filled with lions and tigers, unless he has some trait/ability to artificially protect himself, hide or build social communities as defence agains preditors.

Those within the community who cannot learn to make tools or socialize will not live. Those who do, will survive and pass on these traits and knowlege to their offspring. Taking this to the world of 2007, those who learn to protect themselves, learn a saleable skill and so on. The others stand at freeway entrances with signs.

 

[MagicaPractica]

Thank you, but was it a good read?

Kind of fun fluff horror/adventure novel. I read it all the way through but I can't say I'd really recommend it to anyone. It was something to read. I won't be picking up the sequel. I think they made a movie out of it.

 

[xssve]

The only way I intended to define forward, if I did, was as evolution might, or has done it.

Let me get more specific on some of these none physical items.

What drives their evolution? They've obviously evolved. Is it our knowledge? Has Nature built in an evolutionary trait into knowledge stipulating, for instance, that as we learn, our ability to learn changes, or will change? And if so, to what end, if any?

It is obvious, or so some say, that physically, we do change, and for a purpose. In the female, we are different from others. It is the female that has the "plumage," if you will. And in that, it has been said that females are "striving" to be more beautiful, more comely. For instance breasts, which seem to have no function other than to attract (glands don't need breast size to provide milk).

So what is it with consciousness as exhibited by us, and our growth from the past? To what in the future? Any extrapolations?

There isn't any back and foreward in natural selection, there are only stressors and adaptations.

The capacity for abstract thought is an adaptation, the stressor likely rapid climatic shifts. Women supplied the bulk of the neolithic diet, and successful gathering requires well developed episodic memory, cognitive mapping skills, etc. in order to recall where certain plants can be found and at what time of year - all the more complicated under changing climatic conditions, which requires abstraction in order to classify soil types, moisture levels, etc., where such plants might be likely to be found - abstract, catagorical knowledge. Women evolved to be shoppers you might say, and selection favored those who know where to look for the best bargains.

An important point because while Apes have been demonstrated to be able to communicate on a symbolic level, they do not appear to create abstract catagories - i.e., they can anticipate the appearance of a banana, but it's that banana, they have no concept for banana's, in general, i.e., as a subcatagory of fruit, subcatagory of edible vegetation, etc.

So, what we call intelligence is essentially based on this expanded capacity for abstract thought, and the expansion of the various forms of memory that maximise it's potential, eidetic, episodic, mimetic, procedural, etc.

Abstraction then spurs the selection of expansion of other forms of memory that are vestigial in apes, and are concerned with language: syntactic and lexical specifically, which make language possible.

Language is selected so that women can pass on procedural knowledge and cognitive mapping skills to their children, giving them a selection advantage in turn, and this cumulative selection advantage is what enables the rapid spread of these inherited mutations - the "smarter" females are better adapted, eat better, can support more children, and have fewer die in childbirth, and are able to extend this nutritional advantage to their mates and offspring, and so on.

The sorts of things we currently value, mathmatical ability, etc., abstractional specialization, is mostly an artifact of rapid cereberal development, it's essentially a new trait, probobly only a few hundred thousand generations old.

To be perfectly blunt about it, overspecialization is the sole reason species go extinct, and it's no different for us - should our overspecialization in financial abstraction and technological development compromise our ability to survive within the environment we are adapted to, we will become extinct.

Chances are good that if this theoretical die off is rapid enough, some populations might survive with enough genetic diversity to start over - these would probobly be populations already adapted to similar conditions, aboriginal peoples, etc., who retain the information they need to survive in oral traditions.

Likely, there would be no particular adaptations in this case, faster puberty perhaps, due to the influence of environmental neurotoxins - these are essentially stressors to organic systems, and the organism "speeds up" metabolically, as it "senses" it's chances for long term survival compromised, and so increases breeding frequency and decreases intervals - but that is happening now, and it appears to be a mechanism that already has a long history, often observed in populations under stress.

Longer gestation periods and extended childhood and adolescence however, serve to maximise the cereberal growth that made the abstraction possible to begin with, so it's self correcting to some extent, you might say.

You just need to be smart enought to feed yourself and your children essentially, the rest is mostly of academic interest.