Evolution: Fact AND Theory

Let's imagine a man that lives in Maine where it is very cold. The man is an avid hunter, so he goes out and buys 20 dogs to start a hunting dog breeding business. Some of the dogs have long, thick fur, and some of the dogs have short, wiry fur. The dogs with the short, wiry fur are not suited to live in a cold climate. The short-haired dogs will freeze to death, and they won't pass on their short-haired genes. The dogs with long hair will survive the weather, and will reproduce, and increase the long-haired dog population. Over time, as this process of natural selection occurrs more and more, the hunter will have a population of dogs that is almost exclusively long-haired. Some of the dogs may even develop genetic mutations that allow them to have even longer and thicker fur than before, and thus be even better suited to their environment.

My friend Rob has the following analogy for divergence within a species:

All dogs used to be wild and looked like wolves (or WERE wolves). Now we have Dacshunds and St. Bernards, specialized for their various roles by selective breeding of certain traits. Now we have two species no longer capable of breeding (unless the St. Bernard male is really cute and the Dacshund female is REALLY brave).

Rob says, "This explains species differentiation through selective breeding. If for example, Dacshunds formed/evolved in hot areas (short hair and need to go after badgers) and St.Bernards formed in cold areas, then their herds migrated to meet, they would no longer be able to breed between them. Bingo- two different breeds that will continue to evolve seperately. Thus, one species has become two. Creationists say no species can branch to become two new species, dogs have shown that it can and does happen."

• Notes from an Evolution class I took in college
• Creationism deconstruction page