Tens of thousands of children conceived by donors are grown up now and wondering who their fathers are. Advances in DNA testing are helping them find out
Researchers are shocked by the unexpected results of a large new genetic study that appears in the journal Human Evolution. The findings indicate that either most animal species and humans originated at approximately the same time, or some major population crash wiped out most of the original species.
In the past, researchers studied DNA in the nucleus of cells, which differs markedly from one species to another. But the new study analyzed a gene sequence found in mitochondrial DNA. (Mitochondria, the powerhouses of cells, produce about 90 percent of a cell’s chemical energy.) Although mitochondrial DNA is similar across all humans and animals, it also contains tiny bits that are different enough to distinguish between species. This difference allows researchers to estimate the approximate age of a species.
The researchers analyzed these gene sequences in 100,000 species and concluded that the event—either the simultaneous appearance of humans and most animals, or a population crash—occurred about 100,000 to 200,000 years ago. That proposal challenges the bedrock of evolutionary theory.
The same authors found other genetic evidence of a relatively recent population crash for all species, which they called “almost a Noah’s Ark hypothesis,” in a 2014 study in PLOS One. They quickly dismissed that notion, though, and said climate cycles offered a more likely explanation.
According to traditional evolutionary thinking, all living things on Earth share common ancestry, with species evolving through a slow process of random mutation, natural selection, and adaptation over roughly 3.8 billion years. The idea that humans and most animals suddenly appeared at the same time a mere 200,000 years ago or less does not fit with that model.
“This conclusion is very surprising,” study co-author David Thaler told AFP, “and I fought against it as hard as I could.”
Nathaniel Jeanson, a cell and developmental biologist with the young-earth creationist organization Answers in Genesis, understands why Thaler and other evolutionists would want to fight against the findings. “There’s a great danger to the evolutionary model in this study in ways they don’t quite realize yet,” he noted on AIG founder Ken Ham’s blog.
Most creationists do not believe that humans and animals share a common ancestor, and young-earth creationists also believe the Earth is as few as 6,000 years old. Still, the study’s results are exciting because, if accurate, they could not only challenge evolutionary theory but also support the Genesis account of creation.
The study also indicated the living world is made up of species with clear genetic boundaries and few or no intermediates between them. On his blog, Ken Ham of AIG said that was exactly what one would expect to find based on the Biblical account of creation. Evolutionists do not expect species to have clear genetic boundaries since they believe all life descended from common ancestors. But Ham said creationists expect genetically distinct species because the Bible tells us God “created each kind to reproduce according to its kind.”
According to the Genesis account, Ham added, all original species came into being at the same time because God created all the different animal “kinds” during creation week. Further, all species that survived the global flood of Noah’s day got off the ark together after the flood.
Andrew Jones of the Discovery Institute said that whether one interprets the study to indicate a simultaneous appearance of humans and animals or a population crash, both views could point to intelligent design. “Either way, if the paper is right, it would be a shock to established scientific expectations,” he wrote on the organization’s blog, Evolution News & Science Today.