Friday, November 13, 2009

Life After Death: The Message of Evolution

Now Dinesh accepts evolution. Dinesh D'Souza : Life After Death: The Message of Evolution

So how does he link evolution with life after death?

Is there life after death? One way to answer this question is to examine whether nature reveals some kind of a plan for life. We’re seeking not just any plan, but a plan that shows a progression from perishable things to imperishable things. Yes, a plan that develops from something like inert matter to something like consciousness or the mind would do very nicely. That’s because consciousness and mind have qualities very different from those of material bodies, and it’s possible that these qualities enable consciousness and mind to survive even after bodies perish.
Biologist Jacques Monod writes in Chance and Necessity that “chance alone is at the source of…all creation in the biosphere.” Insisting that our lives are the material products of a random process, biologist William Provine concludes that “when we die, we die, and that’s the end of us.”

This position has been argued most eloquently by Stephen Jay Gould. In Full House, Gould points out that the earliest forms of life were bacteria. “Now we have oak trees, praying mantises, hippopotamuses, and people.” Even so, bacteria haven’t been eliminated in the struggle for survival; indeed they outnumber all the other species put together. Somewhat wryly, Gould writes that we live in an “age of bacteria” confirmed by global “bacterial domination.”

Gould concedes that one can trace a continuous lineage from one creature to another, but this, he argues, does not constitute “progress” of any sort. After all, “Invertebrates didn’t die or stop evolving after fishes appeared” and similarly “fishes didn’t die out or stop evolving because one lineage…managed to colonize the land.” Mammals emerged later than reptiles, but reptiles are still around. On this basis Gould argues that it is mere arrogance for man to place himself at the top of the evolutionary ladder; in reality, we are the products of a fortunate series of accidents, just like every other life form. Re-run the tape of evolution from an identical starting point, Gould says, and there wouldn’t be humans but rather radically different creatures populating the planet.

Gould’s position was conventional wisdom in biology until a decade ago, but now some of the world’s leading biologists are challenging it. Two of them are Christian De Duve, who won the Nobel prize for his study of cells, and Simon Conway Morris, who is a leading expert on the fossils of the Burgess Shale. Duve and Morris argue that all the talk about randomness and contingency is overstated. In fact, they insist that evolution among several species has followed predictable pathways. Eyes, they contend, have evolved on separate evolutionary lines on multiple occasions. Placental and marsupial mammals are not closely related, and yet they have developed with similar structures and forms. Morris writes that “each group has independently navigated to the same evolutionary solution.”

Duve and Morris don’t deny the factor of chance, but they note that chance itself follows a largely predetermined trajectory. Paradoxically, chance mutations and varied environments nevertheless lead to evolutionary convergence. To understand how this might happen, think of tossing a coin several times; each toss produces a random result of heads or tails, but with many tosses one can predict with a high degree of certainly roughly how many heads and tails will occur. Or think of water descending from a mountaintop—there are many available tracks for it to follow, but they all point in the same direction, downward.

OK, that's certainly a thought, and we can run with this as a model. Water runs downhill from the tops of mountains, after falling as rain or snow. The force of gravity pulls the water downward until it reaches the ocean. I suppose the courses of rivers and streams could be likened to pathways leading to increased complexity, to the development of minds, and to consciousness.

Now, if we draw the comparison, we can picture rivers as populations evolving toward whatever future is represented by the ocean.

The thing is, in the case of rivers running to the ocean, some of them wind up feeding into lakes, which then empty into the ocean. Though there are some dead seas that don't empty into any other body of water, the vast bulk of the water on the planet winds up in the ocean.

When it comes to living things, the vast bulk of living things on this planet is bacteria, microbes, and very simple organisms, none of which are known for their mental prowess. And there doesn't seem to be any tendency for populations of these creatures to evolve toward consciousness. If anything, the creatures that develop consciousness seem to be the very rare dead-end. If anything, rather than a stream of water flowing toward some inevitable destination, achieving consciousness is almost like drops of water being tossed upward by turbulence onto a mountain top.

Consciousness appears to be possible in this universe. (After all, we have it.) But so far, of the many species on this planet, very few have developed it in four billion years of evolution. That's an awfully long time for a river to run to the sea.

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