Klaus Heine
1983 Jahrbuch für Geschichte Lateinamerikas – Anuario de Historia de America Latina  
During the Ice Age, when the sea level was lowered (submerged sea levels lay 17,000 years before present -130 m to -170 m in Australia and -90 m to -130 m off north east America) 1 , Asian people could pass the Bering strait between Asia and Alaska. From there they spread all over North, Central, and South America. At some sites in Mexico bones of mammoth and other early--dated extinct Pleistocene faunal assemblages were found associated with human artefacts. The Tepexpan skull of the Basin of
more » ... ll of the Basin of Mexico was thought to be the first Mexican for many years, but nowadays we have evidence of much older human sites. The stone age hunter did not influence his natural environment in Mexico. Yet, as early as 5,000 years before Christ the people of Mexico began to cultivate different plants 2 . Primitive irrigation schemes were built more than 4,000 years before present. Therefore, we must be aware of the influence of men on the natural environment -on purpose or unintentionally. During thousands of years civilizations developed and declined, migrating people reached the Central Mexican Highland; breakdowns of civilizations occurred, new ones rose. The population density varied, although through the times the number of human beings
doi:10.7767/jbla.1983.20.1.121 fatcat:iyhqenvq5bemthpg7eiqht4sla