Ear infections likely killed off the Neanderthals, according to scientists who claim to have cracked the mystery surrounding the species' extinction. While antibiotics are taken for granted in the modern world, a lack of sophisticated medicine 40,000 years ago is believed to have seen the archaic species suffer from the common childhood illness and then perish. Moreover, Neanderthals were more prone to contracting an ear infection as they had smaller ears, providing a tighter space for bacteria to become clogged up. This is believed to have led to breathing and hearing problems and pneumonia.