Did you know that cells are programmed not to evolve?
It makes sense if you think about it. When scientists study heredity, what they usually look at is the differences in genes from person to person. But rarely do they analyze the sameness within species. Sure, we see different breeds of dogs, but a dog is still a dog. No matter how much interbreeding you try, you aren’t likely to get a cow-dog, because the two animals are too different.
Why does this happen? Because the basic body plan is preserved by the reproductive cell.
It’s true that genes vary from person to person and are subject to mutations (most of them harmful), but scientists are discovering that in embryos individual genes don’t take over until after the major body plan is already established. The reproductive cell is programmed by the mother to start the major cell development for the head-tail, left-right, and front-back axes of an embryo before new cells are allowed to move in to build the individual organs and appendages. Kind of like the molecular version of Norton Antivirus, the cell keeps the new genes from messing up the structure of the developing embryo.
In essence, the embryo is started on the path to becoming a human (or a rat or a groundhog or a fruit fly) and then the basic cells are ‘locked down,’ so they cannot be changed at a later stage of development. This would be why we never see a human embryo accidentally develop into a dog, because the basic body plan can’t be changed by the individual’s genes.
Thus, reproductive cells are programmed to reject any type of major deviation from the body plan of the mother—the very thing the theory of evolution depends on.
What do you think? If evolution is an active process, why don’t the major body plans change over time? Is every species so perfectly evolved?
References: Williams, Alex. “Heredity is functionally cellular, not genetic, and life’s history is discrete, not continuous,” Journal of Creation, 28(3), 2014, p. 73.
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