Evolution in humans specificaly

[Sihvyl]

I was reading through the other evolution topic, and it got me thinking.

Animals seem to 'accept' their reality. Like someone pointed out on the other thread; birds fly south, and they continue to do it on a cause/effect basis. Cause= cold/lack of food, Effect= leave (I wonder if birds really have the intention of going for warmth, or moreso just going somewhere hoping that the cold will go away.) Cause= leaving is good & warm, Effect= Birds continue to leave to escape the cold. So on and so forth the cause and effect works it's magic to the point where the birds staying north die, and the major genetic trend is with the south goers.

But, humans, are more complex then that. Do you think in order for humans to evolve, we would conciously have to accept our reality? That seems a very vague question. Let me explain. As humans (we'll use the birds going south example) we would realize that there is a lack of food, and that it's bloody cold. But, we don't care. Some would choose to go find some heat and food, but others would stay to "stick it out". With the defiance of our reality (mind over matter, addicts not accepting their addiction, driving! :o , etc.) do you think that we are restricting if not stopping evolution from taking place, since we do not "have" to abide by the cause and effect system that nature goes right along with? We adapt by creating new ways of going about things, and animals adapt because they are subjected to evolution through the reality of their nature dependence?

Just a random thought....what do you think about it?

[Severian]

Originally posted by [email protected] 20 2005, 06:19 PM
With the defiance of our reality (mind over matter, addicts not accepting their addiction, driving! :o , etc.) do you think that we are restricting if not stopping evolution from taking place, since we do not "have" to abide by the cause and effect system that nature goes right along with?
No. Intent, consciousness, "defiance of reality" have nothing to do with it. If moving south gave a survival-and-reproduction advantage, and it was genetically based, evolution by natural selection would occur.

What does blunt natural selection for humans: civilization. People tend to survive and reproduce no matter what. The main traits which confer Darwinian advantage now: wanting to have lots of kids, and high fertility. If these traits are genetically linked (a big if when it comes to wanting to have children) they'll tend to slowly increase.


Cause= cold/lack of food, Effect= leave

Nobody's shown that this is why birds fly south, and certainly there isn't any proof of intent. For evolution by natural selection to occur, it has to be more like this: cause=gene, effect = trait or behavior.

[Sihvyl]

Thanks for the reply Sev. Got some questions though. I'm not too educated on the topic...


No. Intent, consciousness, "defiance of reality" have nothing to do with it. If moving south gave a survival-and-reproduction advantage, and it was genetically based, evolution by natural selection would occur.

So, lets say in the case of people moving south. Some people would go south while others stayed north. The people in the south would probably have better living conditions and such considering the warmth and all, which would mean a survival-reproduction advantage. But, the people who stayed up north would by no means die out, they might have some disadvantages considering their climate. So for the sake of arguement, lets say the south goers keep going south and they get a gene for this, but when they return from their migration, they refuse to mate with the north goers. Now the north goers could technically survive forever unless something intervened, and they haven't mated with the south goers to acquire their genes, so they lack that gene right? Lets say the two groups continue their seperations, never mating. Does this mean that we essentially would have two different types of human beings because their genes differ? Or would the south goer genes somehow become part of the northeners genes? Thanks in advance for listening to this madness...lol, sorry if it's a silly question.

Also...

cause=gene, effect = trait or behavior.

I always thought it worked kind of like Cause=(cause + effect * frequency)=effect(gene)+reproduction frequency/time=evolved species.

Like....[Cause= cold, effect of cause= thought (damn it's cold)] effect of combined cause and effect in terms of another cause= find warmth, effect= went inside.Then all over again: cause= cold, effect= remeberence of what worked in becoming not cold, effect of combined cause and effect=went inside. Each step becoming more simple until we come to: cause=cold, effect=go inside. At that time we can say that going inside is a part of us.
Maybe thats what you meant though, if so, the work inbetween deserves to be mentioned.

[Rasta Sapian]

good topic,

I think that there is more to the migration of birds than the fact of a lack of food in the fall months for the northern hemisphere for example. Birds like Fish (salmon) for example travel hundred or thousands of miles to spawning sites or nesting sites the very same sites where they were born, this pilgramige by a specific animal community or group are tied in more deeply with the movements of the earth ie. wind currents and temperature changing direction and tempurature certain times of the year. as well as sea currents, salinity level ect.

At the same time these animals are easily affected by changes to the environment in which they live and breed, mankind is the facter that has the most altered the specifc ecosystems via industrial adaptation and aquicatulture and agricultural adaptation.

Man, has adapted the world to fit his/her objectives for survival, the wildlife is now suffering the consequences of our actions!

example 100 year case study of fishing industry in Grand Banks NFld. Canada; The island and its north atlantic waters were once full of Cod schools and marine abundance. The land was home to an indigionous tribe of beauthic Indians, hunter and gatherer type, said to have given rise to the term red skin, from the red orca body paint used. These were the first Indians seen by European fisherman who sailed across the atlantic in the summers to fish and return to western europe in the fall with boats full of fish. The natives would hide from the fisherman, not needing trade, after the settlements were abandoned for the winter, the Indians would salvage all metal and canvass material which they could then reuse for themselves for hunting. They followed the migration of the Caribou and migrated themselves in the winter to better hunting grounds.

Over the past century or two with the settlement of Europeans in Newfoundland the Beauthic Indians have been extinct, ie. dead end species. the fish stocks have been diminished ie. Cod, but the off shore rigs are doing wonderfull, that is evolution!

[amos]

Originally posted by [email protected] 21 2005, 12:49 PM
cause=gene, effect = trait or behavior.
I think what Severian means is something like this:

We have some sort of creature which eats leaves or something from bushes/trees. It's small enough that, it can only reach some of the leaves on any given tree. The more food the animal eats the more successful it is in breeding/reproducing. A specific one of these animals is born with a very small genetic mutation which causes its kneck to grow 1% longer than that of its' non-mutated brethren. As a result of its slightly longer kneck it can reach slightly more of the tree than others of its species thereby making it slightly better at reproducing.

Its' offspring inherit the mutation, making them slightly more successful in the reproduction stakes too. Over a number of generations these offspring multiply to form a significant proportion of the population as a whole. Within this sub-population another animal is born with another mutation making its' kneck grow to 2% longer than the norm. Etc.

Over 1 000s to 1 000 000s of generations similar genetic mutations occur multiplying the effect. Et voila - the giraffe.

The mutations are random, there is nothing to say that another kneck lengthening gene will be switched on. Some mutations might switch it back off, some mutations might affect leg length. Nothing is predictable.

What is predictable is that if the mutation confers some sort of reproductive advantage then it might result in the whole population a number of generations from its' emergence being descendents of the original mutated animal. Separated groups may diverge if there is no reproductive contact. We are not talking small amounts of time we are talking about geological periods.

As I understand it that's how a random mutation occurs according to natural selection. The gene for a longer kneck confers a reproductive advantage. Therefore more offspring are born carrying the gene until eventually it snowballs and the population at large tends to carry the gene.

The trait (effect) results from the gene (cause).

I'm not a biologist but that's the way I think it goes.

Cheers
Amos

[TheReadMenace]

I'm with Amos; I'm not a biologist, but I have read a few things.

From what I understand, evolution is never stopped, but proceeds under altering circumstances. With humans, for instance, we adapt to surroudings that we help create (production, consumption, industry, farming, et cetera) and that spurs evolution based upon the environment we live in.

Something like that. I don't know. Interesting stuff, though.

Andrew