Re: Why are there so many kinds of plants and animals on earth?

Date: Mon Oct 12 14:22:59 1998
Posted By: Dan Berger, Faculty Chemistry/Science, Bluffton College
Area of science: Evolution
ID: 904429936.Ev

Message:

What are the chances that so many interdependant plants and animals (and many more now extinct) would all exist at the same time and place with all of the necessary elements to live for a designated period of time and then to reproduce each with a compatable species having both male and female? It would be asking to much to ask for a mathamatical calculation of the ratio of the possibility of this happening. Maybe you could just give me a general idea of what the chances are. There are many more factors that can be entered into this equation. But this is a good start.

While no one is qualified to give anything like an exact (or even an order-of-magnitute) calculation of this, I think I can give a very good idea: the probability seems to be pretty near unity (100%).

This is not just a simple-minded "it's so, so it must be so" argument, though many people like to give that argument; many even believe it. Instead, I'll try to guide you along by unpacking your question.

What are the chances that so many interdependant plants and animals (and many more now extinct) would all exist at the same time and place with all of the necessary elements to live for a designated period of time and then to reproduce each with a compatable species having both male and female?

What you are asking is equivalent to this: "What is the probability that a tornado traveling through a junkyard will assemble a 747?" The answer is, of course, essentially zero. But neither this nor your question have much to do with the real situation; both are asking about assembling a complex system totally from scratch.

Instead, the more pertinent version of your question is: "Given living cells on some pattern" - let's use the existing pattern since that's what we know - "is it probable that complex inter-relations between different life forms could arise spontaneously?" I think, as do professional biologists, that the answer is yes. (Current objections ride on whether living cells themselves can arise spontaneously.)

Some reasons:

Forms which did not interact with their neighbors would not be taking advantage of all the opportunities open to them, and so would be disfavored to survive.
Forms which only interacted with one or two of their neighbors would have less flexibility, and so would be disfavored to survive.
Forms which were totally dependent on a particular neighbor or neighbors would be tied to the neighbor's survival, and so would be disfavored to survive.

Now, obviously, counter-examples can be found for all of these statements; one example is the koala, which is totally dependent on the eucalyptus tree for sustenence. The result, of course, is that if the eucalyptus becomes extinct, the koala will follow.

But more successful forms will be more adaptable, and so we will see an ever-growing complexity of ecological relationships based simply on the "desire" of living things to be as versatile as possible.

Some useful resources:

The Talk.Origins web site.
The home page of SCICHR-L, the Science and Christianity E-mail list. I especially recommend the book reviews and essays (my contribution is her e). This site is a good place to learn that not all Christians belong to the so-called Institute for Creation Research.

	Dan Berger
	Bluffton College
	http://cs.bluffton.edu/~berger

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