The Bühl moraines, in Lake Lucerne, are estimated as having been deposited between 16,000 and 24,000 B. C., during the Early Magdalenian stage of post-glacial time, which would, therefore, be contemporaneous with the earliest settlement at Susa.[81] The climate of Europe was then somewhat colder and much moister than at present. The ice-cap extended much farther south in middle Europe than in Russia or Siberia. Under these circumstances central Asia probably enjoyed a much moister climate than at present, without extreme cold. The Caspian and Aral Seas occupied a much larger area than at present, and were very likely connected. The Tarim basin may well have been a great lake surrounded by a zone of garden instead of the sandy waste which it is to-day. Conditions of increased moisture would have made the now parched regions of the Iranian plateau an exceedingly rich and favored region. Toward the close of the Post-glacial Epoch the mountains were probably well forested, but alternating dryer times would have brought open glades, with lakes interspersed. When Europe changed from tundra to forest man became largely a fisherman, more or less settled at some favorable spot, and collecting his vegetable food in all directions. The same may well have been true of life at this early date in Persia. The man hunted or fished, the woman and the children gathered all kinds of animals and plant food, berries and other fruits, acorns and other nuts. One of the richest sources of food must have been the roots, tubers, and other underground stems. If there were any patches of richly seeded grasses or grains on the near-by glade or hill, we may be sure that the woman did not fail to beat off the ripe seed with a stick, and carry it home with her. The primitive family was not dainty or particular in its appetite. The women were the first botanists, the first to notice the nutritive, medicinal, or poisonous qualities of plants, and the first physicians.[82] When she turned homeward with her load of spoil, some berries, seeds, and small bulbs doubtless fell to the ground and escaped her notice. These grew and flourished in the richer soil around the hut or shelter, for all the garbage could not have accumulated in the hut. Some unusually observing woman noticed this, and protected the plants, or even cultivated them a little with her digging-stick, and pulled out some of the largest smothering weeds. She began to plant a few others, and gradually started a garden. The garden is older than the farm, and hoe and digging-stick vastly older than the plough. This woman had discovered, and almost created, a new world of science and culture which was to revolutionize life.