Early humans may have started talking half a million years ago Scientists have come a step closer to answering one of the great unknowns in human evolution - at what point did early man begin to use language? A study of five skulls dating back 400,000 years suggests that humans of that time already had the necessary auditory bones needed to understand speech. The findings suggest the origin of language may date back even further than those specimens, to perhaps as long as half a million years ago, research said. Although the ability to speak and understand language is a key development in human evolution, estimates as to when it first arose vary wildly. Some scientists suggest language proper only really took off when anatomically modern humans evolved about 160,000 years ago because they had the sufficiently complex brain needed for symbolic communication. The latest study, however, suggests that language could have evolved at a much earlier date, long before the first cave art paintings of about 35,000 years ago - the first unequivocal evidence of a symbolic brain. All five hominid skulls in the study were found buried in a pit in a cave site at Atapuerca in Spain. They belong to a species called Homo heidelbergensis, which is thought to be a distant relative of the ancestral line leading directly to modern man. Because Homo heidelbergensis was not one of our direct ancestors, the discovery that this hominid was able to understand speech suggests that language may have in fact evolved in a much older common ancestor who lived about 500,000 years ago, the scientists said. Juan-Luis Arsuaga and Ignacio Martinez of the University of Alcala in Spain analysed the bones of the skull's middle ear to estimate the range of sound frequencies that they were most sensitive to. They found that the owner of the skull would have been highly attuned to sounds between 3 and 5 kilohertz which is similar to the 2-4kHz sensitivity range of modern humans whose hearing is geared towards understanding spoken words. "We say that these 400,000-year-old people produced the same sounds that we produce. So this is indirect support for our claim that they had language," Professor Arsuaga said. Chimpanzees, our nearest living relative, by contrast are more sensitive to sounds peaking at two frequencies, 1kHz or 8 kHz, which fall outside of the typical range of sounds used in human speech. Writing in the journal Proceedings of the National Academy of Sciences, the researchers said: "Human hearing differs from that of chimpanzees and most other apes in maintaining a relatively high sensitivity from 2kHz up to 4kHz, a region that contains relevant acoustic information in spoken language." "Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history," they say. "Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range." By Steve Connor Science Editor 22 June 2004 http://news.independent.co.uk/world/science_technology/story.jsp?story=533948 --------------------------------------------- FURTHER REFERENCES GO - "search perceptions" - in SEARCH-ENGINE file-ID www.perceptions.couk.com/olderear.txt