Sorry,I left out a critical point;
>At 06:18 PM 4/27/97 -0700, you wrote:

.... and thus
>any single variation in their food or environment, etc, which produced a
>change in the animal could without question be credited to that single
>change, without a lot of otherwise time consuming proofs.

>     Knows that many characteristics of an organism are inherited from the
>parents of the organism
>     (e.g., eye color in human beings, fruit or flower color in plants),

>*************but other characteristics result from an individual's
>interactions with the environment (e.g., people's table manners, ability to
>     play a musical instrument)

I got carried away and left out my point, here: AND by selecting a
spontaneous species aberation, such as a hairless mouse, or inability to
digest a particular food,and breeding with the homogenous,standardized mice,
progeny can be selected and interbred to quickly produce a growing "colony"
of this new characteristic.In some cases this could lead to a dead end for
carriers of that characteristic.

Pat