Did 90% of all animal species arise at the same time as humans?

Recent articles on-line have alleged that about 90% of all animal species came to be at the same time as humans. See this post for references to four such articles.

What is this idea based on? This article is the main reason for such an idea. (The link given is to a summary. The summary includes a link to the full technical article it is based on, which is freely accessible.) A technique known as DNA barcoding was used. DNA barcoding usually compares a small amount, about 600 base pairs, of the mitochondrial DNA of different organisms. Mitochondria have DNA which is separate from the DNA in the cell's nucleus. DNA barcoding has been used, for example, to check the identity of fish sold for food -- are cheaper fish being passed off as more expensive ones? In some cases, the answer has been "yes." Mitochondria are passed on by females, as sperm do not have mitochondria. To quote from the summary of the article: 
Several convergent lines of evidence show that mitochondrial diversity in modern humans follows from sequence uniformity followed by the accumulation of largely neutral diversity during a population expansion that began approximately 100,000 years ago. A straightforward hypothesis is that the extant populations of almost all animal species have arrived at a similar result consequent to a similar process of expansion from mitochondrial uniformity within the last one to several hundred thousand years.

If true, this has important implications for origins. Ken Ham's blog has posted as article about this idea, and, not surprisingly, claims that these findings are consistent with his young-earth creation model, with survival of land animals after the flood, and not consistent with mainstream evolutionary thought. Perhaps so. Ham does note that the time for this increase in diversity suggested, 100,000, or more, years ago is not consistent with his model, which claims that all land animals arose about 6,000 years ago. He says that the difference in time is because of wrong evolutionary assumptions by mainstream biologists.

It seems premature to reach any firm conclusions on this matter. There have been some substantive criticisms of the barcoding method being applied to taxonomy. This article, from an important journal, Systematic Biology, strongly argues that taxonomic conclusions should not be drawn from only one type of data, be that DNA barcoding, the fossil record, or something else. The article isn't against young-earth creationism, in fact doesn't mention it, but it is against not using all types of data in developing taxonomic relationships. "Systematic," in this context, has to do with classifying organisms.

The Systematic Biology article also indicates some possible problems with DNA barcoding, and points out that the original article, quoted above: "... never [claims] that most 'species' came into existence within the past 200,000 years. Rather, what has come into existence within that time frame is the genetic variation observed in one gene in the mitochondrial genome."

DNA barcoding results, although interesting, and sometimes useful, should not be taken as overwhelming scientific proof of young-earth creationism, at least not yet. And, if such proof becomes stronger, the "young" of young-earth creationism may need revision to considerably more than six to ten thousand years ago.

I'm not sure how the remaining 10% of animal species are supposed to have originated, if, indeed, about 90% of them originated close to one time.

Thanks for reading.