Wednesday, August 29, 2012

Crossing-over


This is the term for the exchange of genes during cell division among similar (homologous) chromosomes from the mother and father. Homologous chromosomes make non-sibling chromatids spiral. Gene exchange takes place where the two chromosomes touch one another. Crossing-over leads to a change in the chromosome gene sequence. Thanks to this phenomenon, genetic variations arise in living things, which in turn lead to intra-species variation. However, there is no question of one species changing into another.
Crossing-over makes for variation within a given species. Exchange of single or paired components takes place between similar chromosomes during crossing-over. Since this will give the chromosomes new combinations of genes, offspring can possibly display characteristics that do not exist in either of their parents.
This is an example of a typical variation. Genes already present in the mother and father are brought together, and new combinations formed. But contrary to what evolutionists would have us believe, there can be no question, of a new species emerging. Therefore, the examples of variation proposed by evolutionists actually constitute no evidence at all for evolution. (See Invalidity of Micro-evolutiontheMacro-evolution Myth, the.)
The biologist Edward S. Deevey Jr. describes how crossing-over takes place within specific genetic bounds:
 Some remarkable things have been done by cross-breeding . . . but wheat is still wheat, and not, for instance, grapefruit. We can no more grow wings on pigs than hens can make cylindrical eggs. A more contemporary example is the average increase in male height that has occurred the past century. Through better health care, males have reached a record adult height during the last century, but the increase is rapidly disappearing, indicating that we have reached our limit.96
In short, such research into plants and animals merely gives rise to certain changes within the genetic information of a species. No new genetic information is ever added. No matter how much you interbreed different types of dogs, cows or horses, the result will still be dogs, cows or horses. No new species will emerge.
96 Edward S. Deevey, Jr. 1967, “The Reply: Letter from Birnam Wood,” Yale Review, 61, pp.   631-640.

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