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Creationism/Evolution Title: Variation within created kinds First published in Creation: Facts of Life Chapter 2: Darwin and biologic change But, “think about it!” doesn’t mean “Stop here!” It means “Start here!” I have been saying, perhaps too often, that the weight of evidence points to “variation within the created kinds.” Do I really mean that all the tremendous variety we see today was built right into the created kinds—just a pair as a minimum for most kinds and perhaps a dozen in one-celled forms with multiple sexes? Could there be enough variation in two created human beings, for example, to produce all the variation among human beings we see today? Answer: “Yes, indeed; no problem!” I get some help here from an unexpected source, evolutionist Francisco Ayala.23 He says that human beings are “heterozygous” for 6.7% of their genes on the average. That means that 6 or 7 times in a 100, the pair of genes for a given trait differ, like the genes for free or attached ear lobes, or for rolling or not rolling the tongue. Now this may not seem like much. But Ayala calculates a single human couple with just “6.7% variety” could produce 102017 children (mathematically, not physically!) before they would run out of variation and have to produce an identical twin. That’s a 1 followed by 2,017 zeroes! The number of atoms in the known universe is a mere 1080, nothing at all compared with the variety that is present in the genes of just two human beings! Take human skin color, for example. First of all, it may surprise you to learn that all of us (except albinos) have exactly the same skin-coloring agent. It’s a protein called melanin. We all have the same basic skin color, just different amounts of it. (Not a very big difference, is it?) How long would it take to get all the variation in the amount of skin color we see among people today? A million years? No. A thousand years? No. Answer: just one generation! Let’s see how that works. The amount of skin color we have depends on at least two pairs of genes. Let’s call these genes A and B. People with the darkest skin color have genes AABB as their genotype (set of genes for a trait); those with very light skins have aabb. People with two “capital-letter” genes would be “medium-skinned,” and those with one or three such genes would be a shade lighter or a shade darker. Suppose we start with two medium-skinned parents, AaBb. Fig. 20 is a genetic square that shows the kind of children they could have. Less than half (only 6 of the 16 combinations) would be medium-skinned like their parents. Four each would be a shade darker or lighter. One in 16 of the children of medium-skinned parents (AaBb) would have the darkest possible skin color (AABB), while the chances are also 1 in 16 that a brother or sister will have the very lightest skin color (aabb). (For details, see Parker, Reynolds, and Reynolds.24) Maximum variation AaBb x AaBb AB Ab aB ab AB AA BB AA Bb Aa BB Aa Bb Ab AA Bb AA bb Aa Bb Aa bb aB Aa BB Aa Bb aa BB aa Bb ab Aa Bb Aa bb aa Bb aa bb Only dark AABB Only medium aaBB Only light aabb Figure 20. All human beings have the same basic skin-color agent (melanin), just different amounts of it. From parents created with medium skin color as diagrammed, all the variation we see today could be produced in just one generation. In the same way, plants and animals created with a mixture of genes could have filled all of the earth’s ecologic and geographic variety. As people break up into groups, however, some groups would develop limited variability—only dark, only medium, or only light as indicated. The Bible doesn’t tell us what skin color our first parents had, but, from a design point of view, the “middle” makes a great beginning. Starting with medium-skinned parents (AaBb), it would take only one generation to produce all the variation we see in human skin color today. In fact, this is the normal situation in India today. Some Indians are as dark as the darkest Africans, and some—perhaps a brother or sister in the same family—as light as the lightest Europeans. I once knew a family from India that included members with every major skin color you could see anywhere in the world. But now notice what happens if human groups were isolated after creation. If those with very dark skins (AABB) migrate into the same areas and/or marry only those with very dark skins, then all their children will have very dark skins. (AABB is the only possible combination of AB egg and sperm cells, which are the only types that can be produced by AABB parents.) Similarly, parents with very light skins (aabb) can have only very light-skinned children, since they don’t have any A or B genes to pass on. Even certain medium-skinned parents (AAbb or aaBB) can get “locked-in” to having only medium-skinned children, like the Orientals, Polynesians, and some of my ancestors, the Native Americans. Where people with different skin colors get together again (as they do in the West Indies, for example), you find the full range of variation again—nothing less, but nothing more either, than what we started with. Clearly, all this is variation within kind. “Gene pool” refers to all the different genes that are present in a population. There are at least four skin-color genes in the human gene pool: A, a, B, b. That total human gene pool for skin color can be found in just one person with medium skin color (AaBb), or it can be “spread around” among many people with visibly different skin colors. In fact, the gene frequencies (percents of each gene) in one AaBb medium-skinned person are exactly the same as the gene frequencies in the 16 children that show five different skin colors. All that individual variation occurs in a group that remains constant: creation, and variation within the created kind! What happened as the descendants of medium-skinned parents produced a variety of descendants? Evolution? Not at all. Except for albinism (the mutational loss of skin color), the human gene pool is no bigger and no different now than the gene pool present at creation. As people multiplied, the genetic variability built right into the first created human beings came to visible expression. The darkest Nigerian and the lightest Norwegian, the tallest Watusi and the shortest Pygmy, the highest soprano and the lowest bass could have been present right from the beginning in two quite average-looking people. Great variation in size, color, form, function, etc., would also be present in the two created ancestors of all the other kinds (plants and animals) as well. Evolutionists assume that all life started from one or a few chemically evolved life forms with an extremely small gene pool. For evolutionists, enlargement of the gene pool by selection of random mutations is a slow, tedious process that burdens each type with a “genetic load” of harmful mutations and evolutionary leftovers. Creationists assume each created kind began with a large gene pool, designed to multiply and fill the earth with all its tremendous ecologic and geographic variety. (See Genesis chapter 1.) Neither creationist nor evolutionist was there at the beginning to see how it was done, but at least the creationist mechanism works, and it’s consistent with what we observe. The evolutionist assumption doesn’t work, and it’s not consistent with what we presently know of genetics and reproduction. As a scientist, I prefer ideas that do work and do help to explain what we can observe, and that’s creation! According to the creation concept, each kind starts with a large gene pool present in created, probably “average-looking,” parents. As descendants of these created kinds become isolated, each average-looking (“generalized”) type would tend to break up into a variety of more “specialized” descendants adapted to different environments. Thus, the created ancestors of dogs, for example, have produced such varieties in nature as wolves, coyotes, and jackals. Human beings, of course, have great diversity, too. As the Bible says, God made of “one blood” (or one gene pool) all the “tribes and tongues and nations” of the earth (Fig. 21). Figure 21 Figure 21. Descendants of created kinds tend to break up into different varieties. Even varieties that no longer interbreed (B) can be recognized as the same kind because they possess only alternate forms (alleles) of the same genes. The existence of distinct types, both living and fossil, says Harvard’s Stephen Gould, “fit splendidly with creationist tenets of a pre-Darwinian era.” Although Gould rejects creation, the facts seem to me to fit creation in our present “post-neo-Darwinian era” just as well. Varieties within a created kind have the same genes, but in different percentages. Take my ancestors, for example, the Native Americans. Certain tribes have a high percentage of blood type A, but that type is quite rare among other tribes, including my branch of the Cherokee Nation. The differences represent just differences in the genes carried by the founders of each tribe as people migrated across the North American continent. Differences from average gene percentages can come to expression quickly in small populations (a process called “genetic drift”). Take the Pennsylvania Amish, for example. Because they are descendants of only about 200 settlers who tended to marry among themselves, they have a greater percentage than their ancestors of genes for short fingers, short stature, a sixth finger, and a certain blood disease. For similar reasons, plants and animals on opposite sides of mountains, rivers, or canyons often have variations in size, color, ear-shape, or some such feature that makes them recognizable as variations of a given kind. All the different varieties of human beings can, of course, marry one another and have children. Many varieties of plants and animals also retain the ability to reproduce and trade genes, despite differences in appearance as great as those between St. Bernards and Chihuahuas. But varieties of one kind may also lose the ability to interbreed with others of their kind. For example, fruit flies multiplying through Central and South America have split up into many subgroups (Fig. 21). And since these subgroups no longer interbreed, each can be called a separate species.
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