Do biological and bio-chemical similarities necessarily mean common ancestors? What else could it mean?
Homology and bio-chemical similarities are really the same argument. Both allege that similar features in different organisms are due to inheritance from a common ancestor. Evolutionists use a number of studies to identify matching traits.
Homology examines similarities of bone structures from different animals. DNA hybridization evaluates the closeness of species relationship by how many DNA strands from different species can be matched.
Electrophoritic analysis show the degree of similarity of proteins from different species. And protein sequencing measures the closeness of relationship by the amount of DNA coding change which is needed to produce the slightly different proteins of different species. One protein sequencing study, for instance, shows there is only one percent difference between chimpanzees and humans.
Forelimbs are the most widely cited example of homology. You may have seen the drawings in school. A human arm is compared bone by bone with forelimbs of whales, dogs, bats, and sometimes a bird wing. After noting how closely they correspond, evolutionists conclude these limbs are based on the same pattern because they evolved from a common ancestor.
More recently, measurable protein and DNA similarities have added more of a scientific punch to the claim. But the argument remains as before. The more similar the form, the closer it is related, and the more recent is the common ancestor.
Based on proteins and DNA studies, evolutionists think that orangutans separated from the man-chimpanzee-gorilla group ten or eleven million years ago. DNA hybridization test indicate gorillas branched away from the man-chimp line eight to ten million years ago. But chimpanzees and humans didn't separate until six or seven million years ago. At any rate, that is what microbiologists believe.
The question is, does similarity necessarily mean relationship? A boat, a plane, and a car are all similar. Each is a means of transportation; each has a type of engine to provide power; each requires fuel; each has a guidance system; each requires a human to make it function; each has an enclosure to protect the passengers; and each has seats for the convenience of the passengers. See the similarities?
But are the boat, plane, and car related? No. They are similar because they were all designed for a similar purpose - transportation. And they all came from the mind of man.
When the Wright brothers first flew at Kitty Hawk, they didn't start from scratch. Engines already existed, seats already existed, and baling wire already existed. Orville and Wilbur did not need to reinvent the wheel. They used all the technology on hand to help build their plane. By the same token, why would we expect the Creator to start from scratch every time he designs a new plant, animal, or human? His proven bio-chemical technology was already at hand.
Many features, proteins and DNA sequences in man are similar to or identical to other primates. We agree. But that doesn't prove man and chimpanzee had a common ancestor. It's just as reasonable to decide that the same Creator made them both.
Many General Motors' cars have a similar look and very similar, often identical, parts under the hood. Certainly, no one claims they descended from a common ancestor. You and I know those cars are so much alike because they originated in the minds of the same designers.
