For many scientists, there’s no woe like wasted information. Consider a new study, which shows how cutting-edge methods can be used to identify ancient fish bone fragments that might have otherwise been thrown away.

Scientists found the 100- to 300-year-old fragments in a human settlement on the coast of southwest Madagascar. They tried to match them to known fish species or families, despite routine challenges — the bones are difficult to identify as just bits and pieces, for one, and Madagascar’s tropical climate degrades fossil DNA faster than colder, drier climates.

“[These fragments] are often overlooked in archaeological studies, mainly because of how difficult they are to identify,’’ says Dáithí Ó Muirí, a geneticist at the University of Western Australia’s Harry Perkins Institute of Medical Research. “What essentially happens is, they either get thrown back into the ground or they end up getting dusty in a museum back room somewhere.’’

Instead, the study used a method called bulk-bone metabarcoding — or BBM, for short.

Here’s how it works: Scientists separate batches of bone fragments by layers of the archaeological site, then grind them together into a powder and extract the DNA. Thousands of DNA sequences — if not millions — can be gathered at once and then compared to a database of fish species and families. It’s a cost-effective alternative to running a traditional DNA analysis on each and every bone fragment, which is prohibitively expensive.

“Nowadays, people are just looking for quick, easy ways to identify materials,’’ Ó Muirí says. “There’s a lot of potential for it to be a very accessible tool in the future.’’

BBM is only three years old, and Ó Muirí was the first one to use it when he analyzed bone fragments from Australia in 2013. But this new study uses BBM on both fish bone fragments and fossils from a tropical climate for the first time.

“There’s so much information that, until now, is just being wasted,’’ says Alicia Grealy, a doctoral candidate at Curtin University who took part in the study, conducted in collaboration with Kristina Douglass, a Smithsonian postdoctoral fellow and director of the Morombe Archaeological Project. “It’s a breakthrough in how we can understand the human impact on biodiversity and humans themselves.’’

The study was able to match the fragments to fish that have already disappeared from southwest Madagascar, a richly biodiverse region experiencing a significant decline in certain species. Some of the bone fragments came from a rare type of nurse shark that’s no longer found in the area, for example, implying that they were overfished by humans.

Kelly Kasulis is a journalist living in Boston and the deputy digital editor of The GroundTruth Project. Follow her on Twitter @KasulisK.