ages and both sexes. Many tombs were evidently re-opened periodically for more burials. The average human life span at this time was probably around 30 years of age, although the size of the prehistoric population is hard to estimate from the available data, but might have been around 1000 people." Nuragic ceramic remains, (from Sardinia), carbon dated to the 13th century BC, have been found in Lipari. The prehistoric Thapsos culture, associated with the Sicani, shows noticeable influences from Mycenaean Greece. The type of burial found in the necropolis of the Thapsos culture, is characterized by large rock-cut chamber tombs, and often of tholos-type that some scholars believe to be of Mycenaean derivation, while others believe it to be the traditional shape of the hut. The housing are made up of mostly circular huts bounded by stone walls, mainly in small numbers. Some huts have rectangular shape, particularly the roof. The economy was based on farming, herding, hunting and fishing. There are numerous evidences of trading networks, in particular of bronze vessels and weapons of Mycenaean and Nuragic (Sardinian) production. There were close trading relationships/networks established with the Milazzo Culture of the Aeolian Islands, and with the Apennine culture of mainland southern Italy. In Sicily's earlier prehistory, there is also evidence of trade with the Capsian and Iberomaurusian mesolithic cultures from Tunisia, with some lithic stone sites attested in certain parts of the island. Another archaeological site, originally identified by Paolo Orsi on the basis of a particular ceramic style, is the Castelluccio culture which dates back to the Ancient Bronze Age (2000 B.C. approximately), and is seen as sort of a "prehistoric proto-civilization", located between Noto and Siracusa. The discovery of a prehistoric village in Castelluccio di Noto, next to the remains of prehistoric circular huts, led to finds of Ceramic glass decorated with brown lines on a yellow-reddish background, and tri-color with the use of white. The weapons used in the days of Castelluccio culture were green stone and basalt axes and, in the most recent settlements, bronze axes, and frequently carved bones, considered idols similar to those of Malta, and of Troy II and III. Burials were made in rounded tombs carved into the rock, with doors with relief carving of spiral symbols and motifs that evoke the sexual act. The Castelluccio culture is dated to a period between 2200 BC and 1800 BC, although some believe