ant wrote:
We are not simply talking about "diversity" in an obvious and dare I say banal sense. We are speaking of a highly radical form of difference - conscious "animals" (that's what we are reduced to aren't we?) and "life"
I would dispute that we are that different from our simian brethren. That's why earlier I was going on and on about the Great Chain of Being. We imagine ourselves as far and away above the animals, but we're not. This is a
speciesist bias. Bonobos and humans share almost 99 per cent of the same genetic code. We are much more closely related to bonobos than bonobos are related to gorillas. Think about that for a minute. Chimpanzees, bonobos and humans are members of the same genus, or would be if scientists in the 1800s had been consistent with their classifications. We were given a separate
homo genus only because people have a hard time accepting our place as the third chimpanzee.
Recall Dawkins' thought experiment of photographs of our grandmother next to a photograph of the great grandmother next to a photo of a great great grandmother, etc. and so on across different species. As Dawkins says, there never was a first human. Never did a
homo erectus give birth to a
homo sapien. We are closely linked to all other life forms on the planet.
Jared Diamond has come up with some very compelling explanations as to why humans with less than two percent difference in DNA have diverged so greatly from our next closest (living) relatives—bonobos and chimpanzees. And also why
homo sapien outsurvived
homo erectus and other
homo ancestors. If memory serves, Diamond suggests that what gave us the edge is a larger brain and capacity for language. Our capacity for language nay have been introduced by a genetic mutation, causing a tiny change in anatomy that gave us the ability to make a large variety of vowel sounds.
In a discussion such as this, it's probably crucial to examine the definition of life. The fact is, there's a very muddy area between clumps of molecules and simple organisms. These are some very arbitrary dividing lines. And borrowing Dawkins' thought experiment, you can perhaps imagine a long line of life forms, each one only slightly different from the next, going back several billion years. At one end of the line is homo sapien and at the other a clump of organic molecules. The concept of gradual transition is very important in understanding evolution.
The other thing we should examine is the nature of consciousness. We are beginning to see that, in fact, most of our decisions, actions, emotions and behavior depend on brain activity that is beyond conscious awareness. How in charge are we really? Do we in fact have more
consciousness than the chimpanzees? We probably do, but it's likely not that much greater.
ant wrote:
The fact that there are "no other theories" does NOT make the current theory the correct one.
Are you saying it does? That's rather fallacious reasoning, don't you think?
We have ONE theory to explain the development and complexity of life (including CONSCIOUS LIFE) spanning eons of geological epics, all within countless environmental theaters, and you'd like to christen it as THE explanation?
Is that reasonable? "This is all we got, so, yeah, this is our origin"
Really?
There are no other theories because Darwin's theory beautifully explains the richness and diversity of life. Evolution is widely accepted as fact because it is supported by a vast preponderance of evidence. If it doesn't make sense to you, that's really your fault. There are many great books out there.
ant wrote:
I'd say the only intellectually honest response here is that the one theory we have is not nearly as vigorous an explanation for ALL aspects of "life," particularly those that relate to what must be considered profoundly mysterious twigs on the tree of life.
This is simply not true. The idea that consciousness or math ability is not explained by evolution is a strange interpretation. We don't understand all the mechanisms of evolution, but there are no "profoundly mysterious twigs on the tree of life." You're just making this up. No credible scientist would agree with this statement.
Actually if you're looking for unlikely evolutionary events, the emergence of RNA and DNA is crazy improbable. To heck with eyes and math ability. DNA gave primitive life forms the ability to create copies of themselves from blueprints. Life forms no longer had start from scratch every time. No more random clumps of molecules. The importance of this event is really quite mind boggling. Dawkins talks about it in
The Selfish Gene. It helps to appreciate the vast length of time we're talking about (in the billions of years) and the notion of countless random sequences. But if I was looking for a miracle, this would probably be it
.