A furry shrewlike creature, one of the earliest branches of the mammalian tree to survive into the modern era

Natural History Museum, London

Thanks to fossil DNA, this ‘island murderer’ is finally getting its day in court

Five centuries after it was likely driven to extinction by the arrival of Spanish conquistadors, a mammal known as the “island murderer” is getting its day in the court of scientific inquiry. Using fossilized DNA, scientists have now traced the evolution of the shrewlike mammal, which comprised at least eight species living throughout the Caribbean before it was outcompeted by black rats that hitched a ride on the ships of Spanish explorers in the early 15th century. Nesophontes, as the genus is known, is thought to be one of the earliest branches of the mammalian tree to survive into the modern era—and a close cousin of the still-living Solenodon (above)—so it has long been of particular interest to scientists. However, tracing its history has been tough. The complex science of extracting fossil DNA is even more difficult in tropical areas, as heat causes DNA strands to break down more quickly. But in a study published today in the journal Molecular Biology and Evolution, scientists have successfully retrieved the DNA from a 750-year-old N. paramicrus skull found in the Dominican Republic. Analysis shows that the genus split off from Solenodon at least 40 million years ago—30 million years after the ancestral species lived among the dinosaurs. Though they’re not quite Jurassic Park, the islands of the Caribbean have been their own form of living museum in preserving some of the world’s oldest mammals. The case of Nesophontes isn’t closed yet.