bones were also found in the lowest layers and perhaps date from the eighth millennium BP, providing some of the earliest known evidence of pastoralism in the Sahara. Among the faunal remains in the middle layers, dated to be roughly between 5300 and 6000 BP, remains of sheep and goats appear more frequently. It has been surmised that this was probably the time period when the shelter was most actively occupied. Fruits and plant seeds were also found. There were more than 30 different species of plant seeds found during the 1982 excavations by Barich, including millet and wild melon. The seeds spanned a long period of time, with the most recent being three date seeds that were radiocarbon dated to 2130 BP, suggesting that the shelter continued to be inhabited intermittently, even after the period of main occupation and subsequent drought. Other finds The pottery at Uan Muhuggiag was found mainly in the top layers. It is of the dotted wavy-line decorated variety that was common in the region during that period. There is evidence that a two-toothed tool was used in order to create equal spacing between the dots, known as the "return" technique. Other finds at Uan Muhuggiag include two hemispherical hollows dug out of the rock, measuring approximately 30 to 40 centimeters, called "kettles". These were found completely covered by deposits and are estimated to be from at least 7500 BP. Several pieces of charcoal were also found, the oldest of which were determined to be 7800 years old. They were probably used in large fireplace pits. The lower levels also uncovered backed and microlithic tools, while lithics such as flakes and arrowheads were found in the upper layers. A total of 406 stone tool fragments were found in level 2a, and 77 in the earliest occupation level of 2d. Palaeoenvironment Uan Muhuggiag was inhabited during the early- to mid-Holocene in what has been termed as the African Aqualithic culture complex, or "Green Sahara" period. Analysis of pollen found at the base levels of the site dating to between 7500 and 5000 BC indicates a wet savannah. Extensive samples from a number of sites indicate that tropical humid plants began to expand northward around 12,000 years ago after a lengthy dry period, eventually reaching deep into what is today the Sahara Desert. Recently, NASA satellites have been able to detect a vast network of ancient river