Identify the skeletal and behavioral traits that represent modern Homo sapiens.
Critically evaluate different types of evidence for the origin of our species in Africa and our expansion around the world.
Understand how the human lifestyle changed when people transitioned from foraging to agriculture.
Hypothesize how human evolutionary trends may continue into the future.
The walls of a pink limestone cave in the hillside of Jebel Irhoud jutted out of the otherwise barren landscape of the Moroccan desert (Figure 12.1). Miners had excavated the cave in the 1960s, revealing some fossils. In 2007, a re-excavation of the site became a momentous occasion for science. A fossil cranium unearthed by a team of researchers was barely visible to the untrained eye. Just the fossil’s robust brows were peering out of the rock. This research team from the Max Planck Institute for Evolutionary Anthropology was the latest to explore the ancient human presence in this part of North Africa after a find by miners in 1960. Excavating near the first discovery, the researchers wanted to learn more about how Homo sapiens lived far from East Africa, where we thought our species originated.
The scientists were surprised when they analyzed the cranium, named Irhoud 10, and other fossils. Statistical comparisons with other human crania concluded that the Irhoud face shapes were typical of recent modern humans while the braincases matched ancient modern humans. Based on the findings of other scientists, the team expected these modern Homo sapiens fossils to be around 200,000 years old. Instead, dating revealed that the cranium had been buried for around 315,000 years.
Together, the modern-looking facial dimensions and the older date reshaped the interpretation of our species: modern Homo sapiens. Some key evolutionary changes from the archaic Homo sapiens (described in Chapter 11) to our species today happened 100,000 years earlier than we had thought and across the vast African continent rather than concentrated in its eastern region.
This revelation in the study of modern Homo sapiens is just one of the latest in this continually advancing area of biological anthropology. Researchers today are still discovering amazing fossils and ingenious ways to collect data and test hypotheses about our past. Through the collective work of many scientists, we are building an overall theory of modern human origins. In this chapter, we will first cover the skeletal changes from archaic Homo sapiens to modern Homo sapiens. Next, we will track how modern Homo sapiens expanded around the world. Lastly, we will cover the development of agriculture and how it changed human culture.