Who would have suspected that a handheld genetic test used to unmask sushi bars pawning off tilapia for tuna could deliver deep insights into evolution, including how new species emerge? And who would have thought to trawl through five million of these gene snapshots - called "DNA barcodes" - collected from 100,000 animal species by hundreds of researchers around the world and deposited in the US government-run GenBank database?
That would be Mark Stoeckle from The Rockefeller University in New York and David Thaler at the University of Basel in Switzerland, who together published findings last week sure to jostle, if not overturn, more than one settled idea about how evolution unfolds.
It is textbook biology, for example, that species with large, far-flung populations - think ants, rats, humans - will become more genetically diverse over time.
"The answer is no," said Stoeckle, lead author of the study, published in the journal Human Evolution.
For the planet's 7.6 billion people, 500 million house sparrows, or 100,000 sandpipers, genetic diversity "is about the same," he told AFP.
The study's most startling result, perhaps, is that nine out of 10 species on Earth today, including humans, came into being 100,000 to 200,000 years ago.
"This conclusion is very surprising, and I fought against it as hard as I could," Thaler told AFP.
That reaction is understandable: How does one explain the fact that 90 percent of animal life, genetically speaking, is roughly the same age? Was there some catastrophic event 200,000 years ago that nearly wiped the slate clean?
To understand the answer, one has to understand DNA barcoding. Animals have two kinds of DNA. The one we are most familiar with, nuclear DNA, is passed down in most animals by male and female parents and contains the genetic blueprint for each individual. The genome - made up of DNA - is constructed with four types of molecules arranged in pairs. In humans, there are three billion of these pairs, grouped into about 20,000 genes.
But all animals also have DNA in their mitochondria, which are the tiny structures inside each cell that convert energy from food into a form that cells can use.
Mitochondria contain 37 genes, and one of them, known as COI, is used to do DNA barcoding. Unlike the genes in nuclear DNA, which can differ greatly from species to species, all animals have the same set of mitochondrial DNA, providing a common basis for comparison.