Is the Shark Related to the Pig?
If all life evolved from, and is related to, earlier forms of life, then closely related animals should also have similar kinds of chemicals in their bodies. As the science of biochemistry has grown, those who believe in evolution have held high hopes that creatures that look similar to each other would also have similar chemicals. For example, insulin from a shark should be more like insulin from other fish than insulin from mammals.
Unfortunately for the evolutionist, chemical comparisons between various creatures don't usually show the same relationships as their evolutionary charts. For example, research at the Medical University of South Carolina compared the hormone relaxin that was produced by pigs and rats with relaxin produced by sharks. The results showed that the pig's relaxin was more like the shark's relaxin than it was like a rat's.
This seems to suggest that pigs are more closely related to sharks than to another mammal, the rat. A similar study comparing insulin showed a closer similarity between the shark and the pig than between the shark and another fish, the carp.
While evolutionists will sometimes point out instances where these comparisons have worked out as they expected, those results are unusual. Normally, these comparisons show that the evolutionary histories and relationships that evolutionists claim are nothing more than imagination. As the Bible says, each kind of creature gives evidence to the fact that it was uniquely created by God.