phenomenon of population growth across the Mediterranean region at this time, which may have been caused by a climatic shift that took place between 850 and 750, which made the region cooler and wetter. This led to the expansion of population into uncultivated areas of Greece and was probably also a driver for colonisation abroad. Ancient sources give us little information on mortality rates in archaic Greece, but it is likely that not many more than half of the population survived to the age of 18: perinatal and infant mortality are likely to have been very high. The population of archaic Greece would have consequently been very young – somewhere between two-fifths and two-thirds of the population might have been under 18. By contrast, probably less than one in four people were over 40, and only one in 20 over the age of 60. Evidence from human remains shows that the average age at death increased over the archaic period, but there is no clear trend for other measures of health. The size of houses gives some evidence for prosperity within society; in the eighth and seventh centuries, the average house size remained constant around 45–50 m, but the number of very large and very small houses increased, indicating increasing economic inequality. From the end of the seventh century, this trend reversed, with houses clustering closely around a growing average, and by the end of the archaic period the average house size had risen to about 125 m. Economy Agriculture Not all arable land in Greece was yet under cultivation in the archaic period. Farms appear to have been small, cohesive units, concentrated near settlements. They were highly diversified, growing a wide variety of crops simultaneously, in order to make consistent use of human resources throughout the year and to ensure that the failure of any one crop was not too much of a disaster. Crop rotation was practiced, with fields left fallow every other year. Though wheat was preferred, in some parts of Greece barley was the staple grain; where wheat was grown it was durum rather than bread wheat. Alongside these, farmers cultivated pulses, vines, olives, fruit, and vegetables. Olives and grapes, which could be turned into oil and wine respectively, served as cash crops; farmers who cultivated land near population centres could also sell soft fruits and leafy vegetables at market. Livestock were of secondary importance. Sheep