<P> Evidence of drainage ditches at Kuk Swamp on the borders of the Western and Southern Highlands of Papua New Guinea shows evidence of the cultivation of taro and a variety of other crops, dating back to 11,000 BP . Two potentially significant economic species, taro (Colocasia esculenta) and yam (Dioscorea sp .), have been identified dating at least to 10,200 calibrated years before present (cal BP). Further evidence of bananas and sugarcane dates to 6,950 to 6,440 BP . This was at the altitudinal limits of these crops, and it has been suggested that cultivation in more favourable ranges in the lowlands may have been even earlier . CSIRO has found evidence that taro was introduced into the Solomon Islands for human use, from 28,000 years ago, making taro cultivation the earliest crop in the world . It seems to have resulted in the spread of the Trans--New Guinea languages from New Guinea east into the Solomon Islands and west into Timor and adjacent areas of Indonesia . This seems to confirm the theories of Carl Sauer who, in "Agricultural Origins and Dispersals", suggested as early as 1952 that this region was a centre of early agriculture . </P> <P> When hunter - gathering began to be replaced by sedentary food production it became more profitable to keep animals close at hand . Therefore, it became necessary to bring animals permanently to their settlements, although in many cases there was a distinction between relatively sedentary farmers and nomadic herders . The animals' size, temperament, diet, mating patterns, and life span were factors in the desire and success in domesticating animals . Animals that provided milk, such as cows and goats, offered a source of protein that was renewable and therefore quite valuable . The animal's ability as a worker (for example ploughing or towing), as well as a food source, also had to be taken into account . Besides being a direct source of food, certain animals could provide leather, wool, hides, and fertilizer . Some of the earliest domesticated animals included dogs (East Asia, about 15,000 years ago), sheep, goats, cows, and pigs . </P> <P> The Middle East served as the source for many animals that could be domesticated, such as sheep, goats and pigs . This area was also the first region to domesticate the dromedary . Henri Fleisch discovered and termed the Shepherd Neolithic flint industry from the Bekaa Valley in Lebanon and suggested that it could have been used by the earliest nomadic shepherds . He dated this industry to the Epipaleolithic or Pre-Pottery Neolithic as it is evidently not Paleolithic, Mesolithic or even Pottery Neolithic . The presence of these animals gave the region a large advantage in cultural and economic development . As the climate in the Middle East changed and became drier, many of the farmers were forced to leave, taking their domesticated animals with them . It was this massive emigration from the Middle East that would later help distribute these animals to the rest of Afroeurasia . This emigration was mainly on an east - west axis of similar climates, as crops usually have a narrow optimal climatic range outside of which they cannot grow for reasons of light or rain changes . For instance, wheat does not normally grow in tropical climates, just like tropical crops such as bananas do not grow in colder climates . Some authors, like Jared Diamond, have postulated that this East - West axis is the main reason why plant and animal domestication spread so quickly from the Fertile Crescent to the rest of Eurasia and North Africa, while it did not reach through the North - South axis of Africa to reach the Mediterranean climates of South Africa, where temperate crops were successfully imported by ships in the last 500 years . Similarly, the African Zebu of central Africa and the domesticated bovines of the fertile - crescent--separated by the dry sahara desert--were not introduced into each other's region . </P> <P> Despite the significant technological advance, the Neolithic revolution did not lead immediately to a rapid growth of population . Its benefits appear to have been offset by various adverse effects, mostly diseases and warfare . </P>

The neolithic revolution began around 10000 bce with the