As we have already seen, much the same animals were reared for the maintenance and comfort of man some five thousand years ago as to-day. Human nature and human requirements vary but little compared with the marked differences which separate one civilization from another, and one stage of culture from one more primitive or more advanced, though these differences are indeed superficial rather than fundamental, but the elementary laws upon which human life depends essentially belong to those things which are fundamental, and in that sense they are eternal. Thus it was that the members of Urukagina’s community partook of beef, mutton or lamb according to the season, as we do to-day; his bill of fare however not only comprised joints but also poultry and birds—chicken, duck, goose, or turtle as the case might be. Fish of all kinds, including both fresh-water and salt-water fish, were prepared in various ways for food, while milk, butter and cheese all appear to have been in regular use. Wheat and barley, as we have several times had occasion to note, were grown on a large scale, and without doubt formed the staple food of the people, providing them with an ample supply of material for cakes and different kinds of bread, including milk loaves and black bread. The principal fruits which were cultivated at this period, were dates, figs, pomegranates and grapes: they were eaten cooked and uncooked, sometimes forming part of a fruit salad, at other times being made into fruit cakes. The date-palm flourished everywhere and was a principal means of support to the poor, while the dates themselves seem to have been used as a medium of exchange. The apple appears to have been cultivated and to have furnished certain drink,[178] while the tamarisk provided a kind of sweet gum. As regards vegetables, onions, radishes, cucumbers and beans appear to have been the most favoured, though various other vegetable products, which have not as yet been identified, are mentioned in the texts. At this early period the art of fermenting cereals was already known, and beer, date-wine, and other alcoholic drinks were to be found in the Sumerian cellars. With their arts and crafts we have dealt elsewhere, as also with their architectural remains, which however afford us little or no information regarding the structure of private dwelling-places, but from the literature we learn that wood as well as brick was used more extensively in their building operations than we should suppose. Wool formed the principal material for making clothes, though linen was also possibly manufactured,[179] while fur was sometimes worn, presumably in the cold weather.