Evolution....

Post by **Chroelle** » Wed Apr 12, 2006 18:29

Well in the last couple of days I have been wondering about this particular subject. Evolution (you know that line of men walking in different manners and with more or less caveman-like looks).

How does it work?
Did a fish pop up out of nowhere or from an ameube and decide that it wanted to breathe air, but heck no if it wanted to go out of the water....

How come some creatures evolve. Some creatures develop skills based on their natural enemies. Like the purquepine (damn spelling). How did it come to it that purquepines got spikes?
IF a purquepine developed from having no spikes to having spikes, how did everyone else decide that spikes might be a good idea?
Were they standing in front of a dismembered friend who got attacked from above and say...."Hey what if we grew spikes on our backs...?"
And how come another then didn't say: Why not poisonous hooks?
And how did they come about growing spikes?

Also man decided to step out of the water (according to some theories). When did he start breathing air? Was it when he surfaced, or when he got to the beach and suddently realised that air was lighter than water? Or ws it when 100.000 men were already lying dead on the beachshore that someone decided..."hey let's go about this another way"?

IF someone can please tell me, that would be great. When is the deciding moment that you evolve.?

Baldie · Post by **Baldie** » Wed Apr 12, 2006 18:44

Complicated Question Chrolle. Evolution can be seen as a series of succesful mutations of one lifeform into another, along the line there are those who failed to adapt and then died out and those who managed to pass on a genectically successful adaptation to a new envirionment to their offspring- Darwin never stated that Man was descended from Apes, what he did put forward is that there was a common ancestor of both in the past, and that man took a different Evolutionary path than the apes, one that seemed to suit man better.

Post by **Chroelle** » Wed Apr 12, 2006 18:56

But that is why I ask the question: When exactly did this mutation take place... Did the fishies just sit there on the shore looking a t the beach and going... Ok I count to 10 and then we jump, or is it more like: I count to 1.000.000.000.000 and then my grandson will jump up and breathe that funny see-through thing....

Baldie · Post by **Baldie** » Wed Apr 12, 2006 19:27

Whether it was a conscious decision is open to debate, I feel that in some ways it was a matter of neccesitity, in that the competition in the seas was getting to be too much and some lifeforms started to venture onto land. From there amphibians devoloped untill we reach the stage of pure land dwellers, and from there over a period of time man finally came about.
So I feel it started as an instinctive way to get more food, and maybe also to stay out of the reach of other predators, untill of course certain predators decided to follow them on land and keep the cycle going.

Post by **Chroelle** » Thu Apr 20, 2006 22:45

Well I am actually aware of the prcess but I love asking the questions a 6 year old might ask you sometimes. It gives a brand new way of looking at things and realising our shortcomings.

If you notice, you still haven't answered my primary question: When and how do one specific individual animal evolve? How does it start out this action and howcome it isn't killed in the progress?
It is actually quite intriguing.

mistergreen77 · Post by **mistergreen77** » Fri Apr 21, 2006 10:15

There would have to be intermediary species but it seems as if it happens suddenly. Probably drastic changes in conditions speed up the process of evolution by forcing genetic adaptation and once things settle down the new type crystallises quickly so there is little evidence of the process. Also, I think isolation must be important.

howcome it isn't killed in the progress?

The failures are killed in the process - natural selection does that. We only see the successful ones, not the countless number that perished.

Post by **Chroelle** » Fri Apr 21, 2006 16:19

That was actually my point when I said this:

Also man decided to step out of the water (according to some theories). When did he start breathing air? Was it when he surfaced, or when he got to the beach and suddently realised that air was lighter than water? Or ws it when 100.000 men were already lying dead on the beachshore that someone decided..."hey let's go about this another way"?

But of course there is such a thing as natural selection that removes the weaker/dumber/first to go out the water ones, but still my question remains. How did they learn how to breathe air? Since the dead guy on the beach didn't tell them what happened to him/what went wrong then who did???

knighteyes · Post by **knighteyes** » Fri Apr 21, 2006 16:53

Yet that no longer seems the case for humans

Evolution can be seen as more as mutation more then a desicon, so when and why is a little hard to answer, more why not

Now if we all come from water dwellers why didnt all the creatures leave the water ?

All speicis of animal .. such as reptial or amphibon end up a humunoid state as well ??

mistergreen77 · Post by **mistergreen77** » Fri Apr 21, 2006 17:53

How did they learn how to breathe air? Since the dead guy on the beach didn't tell them what happened to him/what went wrong then who did???

It didn't quite happen like that. Humans are one of the latest species of mammals. The question would be which one of our most primitive ancestors came up with the trick of respiration. The primitive prototype for lungs. The first creatures might have been like primitive frog from which maybe reptiles evolve. At some stage reptiles learn the trick of having warm blood and live births and then we have primitive mammals. And so on and so forth until there are primates. Later on you have neanderthals and so on and so forth until here we are.

All speicis of animal .. such as reptial or amphibon end up a humunoid state as well ??

No. Once a species thrives in its ecological niche for a long time it does not have to evolve. For primitive creatures the driving force of evolution was earth changes, ice ages, meteorites, etc. Conditions are dramatically changed and new possibilities for life are created - new species are needed to fill new niches. It is amazing diversity of habitat that gives such amazing diversity of animals. Ice age probably sped the development of humans by making our ancestors need intelligence in order to survive. Success of intelligence gave us the ability to thrive in many habitats.

knighteyes · Post by **knighteyes** » Fri Apr 21, 2006 18:13

But why primates .. ??

Zandrav Ibistenn · Post by **Zandrav Ibistenn** » Fri Apr 21, 2006 21:44

There are two features especially characteristic of evolution: opportunism and conservatism.
Couple this with a large timescale and the fact that mutations occur all the time (e.g. in humans, three basepairs mutate in the DNA for each cell division), and then evolution is more understandable.

Evolution thus works like a prototype factory where new designs are continually tested (opportunism due to mutations). The new generation is not just half each parent; it is also the mutations accumulated in the parents genomes. Thus every species change slightly with each passing generation, and if members travel far from each other (perhaps into different environments), they might even evolve into different species.
However, most mutations are harmful and therefore only a few new designs will actually be any improvement over existing ones (conservatism). Adversity - usually caused by radical environmental changes - favours evolution because then new designs are more likely to be advantageous compared to the old design.

Another important aspect of the way evolution works is that "monster mutations" are very rare - grotesquely rare. Monster mutations are when a many mutations occur at the same time working for the same purpose, dramatically changing the design. In practice evolution works by on one little function at a time, very slowly changing the functionality of, say, a limb. That's why Pegasus doesn't exist: there's no way the necessary mutations for wings and the musculoskeletal structures to support them spontaneously evolve in ordinary horses - that's simply so improbable that it's a virtual impossibility.

Similarly, no fish or ichthyosaurus spontaneously turn into a land living creature. But with a million year and all the mutations that period naturally leads to, the slow transformation of the ichtyosaurus into an amphibious creature is not at all impossible.

We have never observed evolution taking place, but we have observed the effects of it.

Post by **Chroelle** » Sat Apr 22, 2006 12:03

There are two features especially characteristic of evolution: opportunism and conservatism.
Couple this with a large timescale and the fact that mutations occur all the time (e.g. in humans, three basepairs mutate in the DNA for each cell division), and then evolution is more understandable.

Actually Yes. That was more or less the answer I was after

This actually explains a lot. Like racial differences (darker skin, eye and hair color, skelatoral differences).
I doubt a six year old would understand what you just said (though propably getting hurt about the fact that Peagasus don't exist) but I did.

Just for clearing something up. I was speaking of "the humans on the beach" as the predecessor of humans. I was just easier that way to make it obvious what I was after.

So thank you for explaining. I think I will go mutate now.