National Geographic recently published an article that once again tackles a question that we've been going over for the past semester: what happened to Neanderthals? In light of the recent human-Neanderthal interbreeding discovery, archaeologist C. Michael Barton goes against the widely held theory that Neanderthals disappeared 30,000 years ago because they were unable to adapt to a cooling world as well as Homo sapiens did. Instead, Barton says that Neanderthals reacted in the same way as humans did to the oncoming Ice age: ranging farther for food and other resources. The key difference that Barton found was that, because of increasingly shared resources and inter-mating, Neanderthals disappeared because they were "genetically swamped" by modern humans.
Genetic swamping occurs when a smaller population is subsumed within a larger one, losing its genetic identity. "In conservation biology, this is called extinction by hybridization," Barton notes. The study consisted of a computational modeling approach that analyzed the genetic information of 1,500 Neanderthal generations.