Evidence humans 'unique' among creation
ASHEVILLE, N.C. (BP) – While the Bible teaches that God designed humans – and only humans – in His image, evolutionary scientists continue to try to explain
the origin of humans' superior intellect when compared to primates. Researchers at Kent State University now seem to think the answer might lie in
differences in brain chemicals.
For their study, published in the Proceedings of the National Academy of Sciences, the researchers analyzed brain samples from humans, chimpanzees, gorillas, baboons and monkeys. They found marked differences in brain chemicals in the striatum, a brain region involved in social behaviors.
According to their findings, human brains produce increased dopamine levels that contribute to uniquely human abilities such as complicated social group formation, speech and language. Human, gorilla and chimpanzee brains showed elevated serotonin, which increases cognitive and social control, but acetylcholine levels, which contribute to aggression, appeared at lower levels in the human brain, Scientific American reported.
The researchers said natural selection shaped the human brain's neurochemical profile, helping us to survive and outcompete with "other apes" and early hominids, numerous humanlike species they say arose after humans split with chimpanzees. But this new research still does not explain why, if the superior intellect and emotional and behavioral complexity of humans made us more fit for survival, natural selection didn't cause any other species to evolve with the same capabilities.
Elizabeth Mitchell, a physician and a writer for Answers in Genesis, said the biochemical similarities among humans, apes and monkeys show not common descent from a single ancestor – a concept Charles Darwin called the "tree of life" – but common design by a Creator. God used similar genetic building blocks to produce features needed in similar organisms and equipped each with the DNA information to reproduce after its kind, she wrote on the organization's blog.
Reducing humans to just one more monkey on the tree will never explain the spiritual nature that only humans possess, she notes. "Ancestral biology cannot explain the origin of the information for physical and mental differences, much less the spiritual differences," Mitchell said. "But the Bible does."