Breeding dogs involves artificial selection where the dog owners select breeding partners to allow changes to occur over generations to ultimately change traits in a the original kind of a dog perhaps similar to a Husky or Wolf downward into a Chihuahua. Such artificial selection is effectively decreasing (or bottle-necking) DNA informational variability via DNA allele genetic function.
The population bottleneck produces a decrease in the gene pool of the population because many (DNA) alleles, or gene variants, that were present in the original population are lost.”
https://www.nature.com/scitable/definition/population-bottleneck-300/
The variations occur due to DNA heredity at reproduction and not by mutational “errors” such as somatic mutations which occur during DNA replication. Such variation does not occur because of some “invisible hand of blind watchmaker” for evolution. There is no way to reproduce a pair of Chihuahua’s upward (i.e. “evolution”) adding back more information and complexity to get this dog back to being a Husky (or wolf) because the genetic data is lost.
DNA Heredity works as the God ordained, “They and every beast (reproduces) after its kind, all cattle after their kind, every creeping thing that creeps on the earth after its kind, and every bird after its kind, every bird of every sort.”
Genesis 7:14 (NKJV)
Due to the loss of genetic variation, the new population can become genetically distinct from the original population, which has led to the hypothesis that population bottlenecks can lead to the evolution of new species.”
https://www.nature.com/scitable/definition/population-bottleneck-300/
This quotation above is self refuting. Here the reasoning is as follows: dogs, of the same species reproduce with other dogs (of the same species) which generate offspring which lose significant genetic information over generations. Eventually these generations cannot reproduce with any dog but themselves. How does this equate into a new dog “species”? Obviously it does not! What we have now is a genetically bottle-necked of bankrupt species of…well…dogs.
https://answersingenesis.org/creation-science/baraminology/suite-dogs/
https://answersingenesis.org/genetics/animal-genetics/hairy-new-findings-in-dog-variation/
