Darwin, God and Genetics

Another post from Talk.Origins:

 

From: Randy Crum <carumba17@yahoo.com>

Date: Tue, Mar 31, 2009 at 9:00 AM

Subject: [OriginsTalk] Darwin, God and Genetics

To: OriginsTalk@yahoogroups.com

 

Except for Mendel, scientists of Darwin's time didn't understand genetics very well. They thought that it involved a sort of "blending". If a large dog mated with a small dog a medium-sized dog would generally result.

 

If genes really DID simply "blend", then genetic change would be constrained. That would effectively make macro-evolution impossible.

 

Consider one of the characteristic of peas that Mendel studied – wrinkled and smooth (the peas, not the plants). Let's say that initially all peas are smooth. Then let's hypothesize that one plant gets a genetic change (a mutation) that results in peas that are wrinkled. For the sake of argument (and to simplify the math in this example), let's say that these peas have four wrinkles. (That would be a reasonable number of wrinkles on something as small as a pea.)

 

What would happen after this if genes blended? In the next generation, you would have primarily plants with smooth peas (since there was only a single plant with wrinkled peas in the previous generation). But that single plant with wrinkled peas could mate with some plants that produced smooth peas. If genes blended, then the result would be in that next generation some plants that yielded peas that were a "blend of smooth and four-wrinkled peas. Simple math tells us that those would blend into peas with two wrinkles. So we would expect to see plants that primarily had smooth peas, with a few plants with peas that had two wrinkles.

 

In the generation after that, again most of the plants would primarily have smooth peas (since the vast majority of plants had smooth peas). But some wrinkled pea plants would reproduce with smooth plants resulting in plants with a single wrinkle. In addition to that, you would have a very small number of two-wrinkle pea plants that mated with other two-wrinkle pea plants. So some of those – though a decidedly smaller number – would also persist.

 

The trend is pretty obvious. Within a few generations, all of the pea plants would be back to being smooth. The reproduction of the overwhelming number of smooth pea plants would eventually "blend" the anomalous wrinkled pea characteristic out of population. Everything would be back to the genetic characteristics of the "created kind" that its ancestors were.

 

A biologist has described it in this way : "[Darwin] believed in blending inheritance, the idea that offspring take on the characteristics intermediate between their parents. But even Darwin recognized that the theory was problematic because if traits were truly blended, then any rare new variant would be progressively diluted by generations of breeding with the mass of individuals that did not share that trait."

 

But genes don't work this way. Genes only work in a way that allows genetic change to persist from generation to generation without any modificatons. That mechanism of genetics allows genetic changes to accumulate over time.

 

So if creationists are correct and God wanted to limit things to remain "created kinds", God wasn't very competent. That's because the mechanism of genetics that God "designed" isn't a form of blending. Instead the mechanism that was "designed" allows evolutionary change to accumulate over time and therefore allows macro-evolution. (The "blending of genes" is just one possible mechanism in genetics that would prevent macro-evolution.)

 

Evidently, if you are a creationist, you believe that God couldn't figure any of that out.

 

Creationism forces people to believe in a very flawed God indeed.

 

On the other hand, if you believe in evolution then God is very competent. The mechanism for genetics is ideal for allowing changes to accumulate and, therefore, ideal for allowing macro-evolution. The evidence indicates that God must be an evolutionist.

 

Randy C.