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Re: "Random selection": an oxymoron.
On Sun, 24 Jan 1999 Dinogeorge@aol.com wrote:
> The randomness is not in the results of removing the lichen and watching the
> resulting moth population change. The randomness lies in such things as the
> existence of moths and lichen to begin with...
The reason the moth story is useful is because it describes a tiny
directional step. Species are the result of uncountable tiny directional
steps. The steps were not random. For example, lichen, as you know, is a
symbiotic relationship between fungii and algae. This association is not
random. As a general rule, single cells will strike up such relationships
with each other. This has happened many times. And there is in lichen a
fabulous spectrum that goes from the two cells having absolute dependence
upon each other to very casual relationships. Indeed, some lichens
consist of the same fungal component with different algae, and vice versa.
Some lichen fungi can do fine without algae, and so on. The point is that
there is an adaptive advantage of some kind that makes these associations
very common. So, seeding a new planet with prokaryotic cells, our alien
biologist would be quite justified in predicting that eventually
cells would strike up relationships with each other. Would the
alien predict that some day one of the most intricately designed creatures
would evolve the intelligence to turn this on its head and claim even
himself a chaotic creation--maybe that too.
> ...and whether and when the lichen
> will be stripped off the trees...
Well, yes. Thanks to our powers of observation we now know that acid rain
strips lichen off trees. It is a _very_ predictable consequence of
spewing tons of coal gas in the air.
>...leaving the dark moths exposed, and whether
> and when there will exist suitable predators to provide the necessary
> selection mechanism.
As a rule, if a prey species is camouflaged in some way you know a
predator is present. Indeed, the predator was the selective force for it
in the first place. This is certainly a very good rule.
> It is not Cope's rule that is medieval; what is truly medival is the idea that
> there are "rules" that evolution must follow. What rule or combination of
> rules resulted in the dinosaurs? Evolution the result of anarchy, and the only
> rules that evolution follows are the laws of physics and chemistry that govern
> the interactions of matter and energy throughout the universe.
Some hypothetical rules on the way to evolving dinosaurs:
1. Animals that could create a shell around their egg could exploit more
niches--at least drier niches--than those that could not.
2. Animals that ensured rapid embryonic growth rates could fuel the
development of more diverse and expensive morphologies.
3. Hotter embryonic growth rates were made possible by parental
4. Increase in neuronal capacity gave greater flexibility in behavior.
5. Need to attend the nest led to increased discovery rates by predators.
6. Increased discovery rates led to need to increase size for protection
of a stationary egg.