The Neanderthal was a lineage of the genus Homo which split from the modern human lineage sometime around 400,000 years ago and occupied vast areas of Eurasia.
The Neanderthals were adapted to open woodland landscapes where they could exploit a wide range of resources. During cold glacials much of their range became inhospitable and Neanderthals survived in the southern peninsulas, in Iberia, Italy, the Balkans and Crimea. Southern Iberia, particularly the coastal south-west around Gibraltar had the most benign climate because of the tempering influence of the Atlantic Ocean, distance from the high mountain glaciers and high latitudes. It was here that Neanderthals persisted without interruption for most of the last glacial cycle in the Late Pleistocene era, a period of around 100,000 years.
No Neanderthal remains have been found in Africa. The earliest evidence of modern humans outside Africa is in the Middle East where a first appearance is recorded around 130,000-100,000 years ago. It was probably in this region that Neanderthals and modern humans first met after 300,000 years of isolation. Today we know that the two lineages interchanged genes with a Neanderthal contribution of around 2-4% to people of European ancestry. In spite of the close proximity of modern human and Neanderthal populations, facing each other across the Strait of Gibraltar, there is currently no evidence to support contact between the two populations. It would take modern humans another 100,000 years to reach the northern shore of the Strait of Gibraltar, spreading from east to west across Europe from the Middle East. By the time modern humans reached this region, the Neanderthals were extinct.
A 4-episode television documentary series on the Neanderthals of Gibraltar, produced by the Gibraltar National Museum, is available for watching here.