OK I thought about this and I have a question.

If we evolved how did the male/female evolution happen?

Not meant to start a arguement, just curious.

Amoeba man... hmmm...

no I meant how did a single cell that we all came from ( according to evolution) make males and females different? we are to perfectly constructed so how is it possible?

http://library.thinkquest.org/19926/text/tour/00.htm?tqskip1=1&tqtime=1007

Right, I was just speculating why we dont reproduce the way many other 'lower life forms' do.

no I meant how did a single cell that we all came from ( according to evolution) make males and females different? we are to perfectly constructed so how is it possible?

The same way a cyclone (hurricane to you yanks ) can change from a 'perfect' single rotating storm into multiple 'cells' - each representative of the original, yet different.

I'm going to let you stew on that while I put the kids to bed

Hi Kona!

Without getting too technical, here's the standard view from the natural selection viewpoint of evolution:

At some point, abiogenesis occurs (the point at which a particular molecular structure gains (at least some of) the characteristics of life (including the ability to make copies of itself).

As a result, there are soon, quite a large number of copies of this lifeform (all identical so far). Random mutation occurs. The vast majority of these mutations are harmful, and the lifeform becomes non-viable. Every once in a while, the mutation confers a non lethal difference in the characteristic of the lifeform. If this difference provides a survival (or reproductive) advantage to the lifeform (they can survive more easily in their environment, or they can reproduce much faster than the other forms), then they will become the dominant form in that environment.

Fast forward for a bit. We're now in an environment with more advanced life, but they still all reproduce via mitosis (direct copies). Another random mutation occurs that doesn't render the victim non-viable. Perhaps it now finds that it can initiate a copying process with another non mutated member of it's type. (Most likely, this was not a one-shot event). Sooner or later, the ability is gained to reproduce by mixing genetic information from two (or maybe even more) members.

This confers a survival and reproduction benefit in the following manner: If a lifeform reproduces by division only, any change in its structure will be passed on to all future copies. Sooner or later, the error rate will become lethal (or at least non-viable in the environment, or change to something else entirely).

Bisexual reproduction however, confers two primary reproductive benefits. First, the commingling of two sources of genetic information (which is primarily identical, with only small differences) provides a great deal of resistance to cascading mutation failure (multiple reproductive sources provide redundancy). Second, the intermixing of different strands of dna also provide more room for rapid genetic variation in subsequent generations. The redundancy tends to help moderate out the more catastrophic cases. This redundancy is especially important as the organism becomes more complex, as there are many more ways to break its structure.

As a result, any species that reproduces in such a fashion is more resistant to catastrophic changes, and is still more adaptable (due to the more rapid variations).

In other words, once life attained the ability to reproduce bisexually, that strain gained the best tools for long term survival (and further evolution), to the point that only the very simplest forms of life are still asexual.

Obviously, there's more to it than that, and we certainly don't know what the particular sequence of events or triggers were. And of course, it is a hypothesis of the natural selection theory of evolution.

Apparently a lot of people have difficulty trying to forge their own opinion and they need a beleivable person to guide them, weather it's a priest or a doctor...

- paxx

paxx, i don't think that the real problem is people having trouble forging their own opinion. the issue is that they don't want their own or anyone else's opinion - they want THE ABSOLUTE TRUTH ( pardon the caps) which leads them to search for something above the level of opinion.

I just jumped in on this. I have held off looking into this thread as it is one that can be very touchy with some people. However, I want to provide a....viewpoint based on faith yet supported by some good old common sense. Aleatoric, you gave a general outline of evolutionary theory; but think about it this way:

If you take all the parts to assemble a cutting edge computer, put them in a cement mixer, turn it on and let it run for a billion years, will you have a cutting edge computer or just a bunch of busted components? Now, take those same components and an individual that has the training and skills, put him/her in a room and in a few hours they can come out with a completed and functioning computer that can do anything from a simple calculation to complex drawings etc.

Evolution is the cement mixer God is the technichan. [Jafo?]

All you have to do is look closely at the complexity and ariety of life and you see *intelligent design*, not the lucky happenings of random chance. The earth, for example is at just the right distance from the sun, further away too cold, closer to the sun, too hot. And we're talking about a narrow margin either way. it's late and I could expound further, but I'll watch and maybe have more to say later. Thanks for your time.

Hope I spelled technichan correctly.

Technician

Ah...hope abandoned you, I'm afraid.....

To amend that analogy slightly.....what if instead of a cement mixer you had a dozen mindless robots and an eternity to 'fiddle' with potential ways to add one component to another.......eventually, sooner or later, all the right bits would be in the right places....and you'd have an accurate definition of 'evolution', [whereas 'God' could just be the the guy who kicks all the junk into the corner, says 'stuff it' and goes watch the football]....

Ah, so it's all sorted then. I am God...

Fuzzy Logic gives generous greetings to all his blessed minions

If human civilization lasts another 20,000 years it would be surprising.

"Civilization", as we know it, has only been around for around 5,000 years.

We may have only developed a complex language as recently at 50,000 years ago.

A million years ago we were basically a bipedal chimp.

The problem is that "very bad things" happen to earth quite regularly. 

Case in point: Anyone ever been to Yellowstone national park? Old Faithful, geizers, etc.  You know why they're there? The entire part of that state is the top of a super volcano that goes up every once in a long long while. When it goes up, it'll wipe out most of North America.  It's overdue.

We also get, every 20,000 or so years, an asteroid hit that is enough to wipe out civilization pretty good. Not kill off all humans (nothing I'm mentioning would cause our extinction as a species). But ensure that 4 or 5 billion humans starved to death or worse.

People also worry these days about global warming. Technically speaking, we should be more worried about global cooling. We're actually in the warm spot in the middle of an ice age (we're in what's called an interglacial period). Historically the earth was much warmer.

Of course, global warming could have a bad effect too of causing the ice caps to melt which would alter the currents in the Atlantic which would in turn cause cooler summers (it's not cold winters that cause ice ages but cool summers).

We don't live on a very safe planet for long term complex life. It wouldn't take a lot to mess up civilization.

That is so true. At the end of the day Humans are just a minor biological species in an ever evolving ecosystem. Surviving natural elements is precarious at best. We are just lucky to have survived long enough to attain intelligence.

With so many natural threats around it's only a matter of time...