Analysing ancient DNA from the tropics is difficult because DNA breaks down fairly rapidly in heat, but a team has managed to tease out some of the species represented by hundreds of 100–300-year-old fish bones from Madagascar.

Short 'barcode' DNA sequences from a region of the genome that tends to vary between taxonomic groups can be used to identify fragmented animal bones discovered at archaeological sites. A team led by Alicia Grealy at Curtin University in Perth, Australia, applied this method to 887 fish bones from a site on the west coast of Madagascar that was occupied by humans in the eighteenth and nineteenth centuries. The authors were able to identify 23 fish families — 10 of which could be narrowed down, with some confidence, to a specific species — including two kinds of shark and various coral-reef-dwelling fish.

J. Archaeol. Sci. 75, 82–88 (2016)