why DID we evolve into humans?

Mmm, I think we need a slightly different approach to this...You can agree that chemistry states very specific causes and effects when it comes to chemical reactions?And that these reactions are already 'established' regardless of any life on earth? As an analogy, you could take languages, which relies on specific established letters, words and grammar rules?So, all possible combinations of DNA ever imaginable already has specific results 'alligned' to them?Hence, what is relevant is only the way DNA is arranged? Similarily, the only way a book is made is by arranging already existing letters and words into specific structures?Therefore, all evolution does is, by trial and error, test slight random chemical reactions until it finds one that works well enough? For example, you can write a new book which is different than anything ever written before without having to invent new letters.It's the functions, or structures, that are important. If an organism can do something it's parents couldn't do, a new function has obviously been added. You could say that the potential for ALL functions is already present in all organisms, but not all are realized at one time. It's the realization, and the process of weeding out the useful realizations, that is the deal here.

I've read some of the articled here. Interesting.A far fetched theory . . . What if evolution on this planet has ended up being `pre-programmed`?

What would it matter? There would be no way to tell, so we go by what it looks like.

It could. Say that all girls in this world suddenly have a sick fetish for guys with 3 testicles and 3 extra layers of insulating fat. In 20 generations or so, the majority of the male population would be guys with 3 testicles and 3 extra layers of insulating fat. 20 generations after that, you'd see nothing but guys with 3 testicles and 3 layers of fat, because they are extra horny and they easily outgrow the world as we know it.

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The Laminator
For goodness's sake, please vote Democrat this November!

Thanks Lam, you've just put me off me dinner!

Nothing wrong thinking about it. Maybe within DNA, complex as it is, there could (maybe not, God knows for sure!) the the description of what life will become, if life survives long enough. The boffins to admit that they've sussed out what 5% of it all means and the remaining 95% of it remains, at present, a mystery.Anyway, going slightly off the rails here. Need to get back on them. This is about Human Origins and I'm venturing into Human Future.

Adding my 2 cents to the original question posed if you are trying to guess why humans are the dominant species or why we evolved to what we are today I feel that our hands and in particular our thumbs are the reason we are what we are today. At some point in time our ancestors left the ground and took to the trees. Becoming good at moving around trees caused our hands to evolve the way they did. Once the hands evolved we were able to grip objects. Once we could grip an object eventually (like space odyssey 2000 depicts) we used an object as a tool and the missing link as they call it was started. Not just one being but groups of beings began to use very rudimentary tools. It was because of our hands and thumbs that we became dexterous with tools and that is the catalyst that started our path towards intelligence. The smarter we got the more ways we found to use tools and the more tools we created and more uses for tools the more our intelligence increased. Those groups or tribes that began to use tools day in and day out evolved to be smarter and walk more upright. Those that were happy to eat nuts and berries followed an evolutionary path that did not include an exponential increase in intelligence.Not sure if this is in the spirit of the posters original thread but if so then that is my opinion as to why humans evolved they way we did.

(I apologize as I haven't read the entire thread, but this reminded me of a quote)

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I think the problem you're confronting is in describing evolution as being "motivated" toward some goal. Simplistically stated, we evolved into what we are by a process of natural selection. There wasn't a stated goal to where we would be headed.

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"You know, the most amazing thing happened to me tonight. I saw a car with the license plate ARW 357. Can you imagine? Of all the millions of license plates in the state, what was the chance that I would see that particular one tonight? Amazing!"-Richard Feynman...the point being (in the way I'm using it) that, the probability seems much more extraordinary in retrospect. Of all the things to evolve into, we evolved into humans!

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Adding my 2 cents to the original question posed if you are trying to guess why humans are the dominant species

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It can be argued that humans are not the dominant species. The E. coli in your intestinal tract outnumber the human population, and that is just one species of bacteria. I really can't understand how humans, who can't live in 70% of the worlds ecosystems (we can't breathe water) are more dominant than species that can survive in 99% of the world's environments. But then again, it is a matter of opinion.

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It was because of our hands and thumbs that we became dexterous with tools and that is the catalyst that started our path towards intelligence.

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And tool use can probably be linked to one morphological distinction between us and the apes: Our ability to touch our pinky to our thumb on the same hand. In other words, we are able to hold a stick like it is an extension of our fore-arm. Chimps, for example, can only hold sticks at a 90 degree angle to their forearms because their are not able to touch their pinky to their thumb. Also, it required a neurological change as well for increased dexterity.Language is also another topic that was touched on earlier. Humans that do not have human contact have both language problems and conceptualization problems. They lack spatial and cognitive skills, even though they are taught in the same manner as children who were exposed to language as a child. Anybody have the latest studies on the tie between language and cognitive skills?

Language development would follow naturally as intelligence increased. There are many different areas of our evolution that made us what we are. I was trying to pinpoint what I felt was the catalyst that separated us from all other species and I think dexterity of the hands started the ball rolling. That was the question I felt the original post was thinking about.re: the dominant species. Shear number or ability survive adversity does not make a species dominant. I know of no other species that holds the future of all other species on this planet in its grasp. We decide as a whole (actually a small minority of our species) decides the fate and future of all species on this planet. We control whether the species of this planet survive or perish. Our choices as a species dictate the length of time that our planet will support a habitable environment for the bulk of the sentient beings on this planet. That in my eyes makes us the dominant species.

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Shear number or ability survive adversity does not make a species dominant. I know of no other species that holds the future of all other species on this planet in its grasp.

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Ever hear of the bubonic plague? Wiped out 25% of the european population. A similar outbreak of an antibiotic resisten Yersinia pestis could possibly reek as much havoc today as it did then. 25% of the population of some sub-Saharan countries is HIV positive. We are far from controlling our own destiny due to the adaptive qualities of microorganisms and viruses. We depend on bacteria for almost everything we have. Just one example, without microorganisms cattle wouldn't be able to digest grass. Microorganisms can wipe out almost any species given the right conditions.However, we are drifting off topic. I am very tempted to start a topic on what is the dominant species . . . something like "King of the World". I am a little biased since I study infectious disease, and like I said before it is a matter of opinion. Could be a fun discussion.

Sorry for the double post.

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Language development would follow naturally as intelligence increased.

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I can't find the studies right now, but if I remember correctly the two (ie language and intelligence) are actually intertwined instead of being a cause and effect system. That is, development of language caused our intelligence to increase, and this turned into a type of feedback loop. It is thought that the thought processes that go into language development also tie into our cognitive skills.

I wanted to expand on the original questions/points posted. In my post, I'm going to refrain from using technical terms like species to help keep the topic from being bogged down with criticism on my definition or use of the word. Unfortunately, I can't think of a general word for "evolution" or natural selection, so I'm just going to use "evolution" when I mean whatever mechanism is responsible for getting us from primordial soup to human.When we look at humans now, we can see some complex mechanisms, for example: eyes. My next thoughts/questions could apply to other organs/mechanisms in humans, but I think it's best to only focus on one thing at a time so the topic doesn't get diluted. If anyone wants to comment though, feel free to use whatever example you want.Humans don't have exclusive claim to eyes. Eyes exist is a many other creatures. I think that some creatures have eyes that are better in some ways than ours, some are worse, or completely different (I'm thinking of insects with compound eyes)In the case of some animals, their eyes operate very similar to our eyes, even being able to see almost exactly like we do.My comparisons about eyes are very general, because I don't have specialized knowledge on eyes, so I'm drawing these conclusions from listening to the Discover Channel and Animal Planet. I don't believe I need more specifics though for my question.If I understand evolution correctly, all human/animal life descended form one species (if you go back far enough). So at what point did eyes first come into existence? Since most creatures have eyes, they must have started pretty far back, right? For if they didn't, that means that multiple creatures developed similar eyes simultaneously.If they did start before whatever split happened to our common ancestor, then how could something so complex have evolved even before we were all different species?Our bodies are filled with complexities, many of which are shared among at least one other group of creatures or another. How can complexities that are so similar have developed independently from each other? Of if they did develop early on, what kind of creature possessed all these traits, then evolved into birds, cats, etc?I admit to being a novice at this, so I'm hoping for some good explanations.

For a good explaination of how eyes might have evolved, including references to examples in nature of each step, Look here

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Aslan is not a Tame Lion

Thanks for the link. I read the text and watched the little video. I thought the logic was poor in the video. Also, there was a severe lack of details and information about eye evolution, however, it might have been toned down to address a specific audience, so I can forgive the lack of information just not the logic.But, I wasn’t really concerned specifically the eye, or how or why it evolved, but the order it evolved. Our bodies are so complex, when did all that complexity get there?According to evolution, was it before our last common ancestor (common to all mammals, and maybe even fish and insects), or did all the mammals etc develop all this complexity independently from each other?In other words: was there some creature that had eyes, ears, liver, heart, spleen, (all that good stuff), and through mutations, some gradually became giraffes, others become people, or cats, bears, etc?I understand no one claims we went from (for example) bacteria to human in one step, that every change was very gradual, so please don’t get sidetracked on my language above.Thanks.