Chapter 6. Human Biological Evolution

Summary

This chapter provides a comprehensive compilation of evidence, current ideas, and interpretation of human biological evolution. Paleoanthropological research aims to explain the process of hominization. The biological approach to understanding human evolution as a self-organizing process focuses on the structural and functional adaptations within the order Primates. During the past decades, significant advances in our biological research concepts allowed an increased understanding of the complexity of the origin of Homo sapiens from early primate ancestors. The issue is introduced by a short review of the main subjects involved in reconstruction of the straightforward evolutionary processes, which led to our uniqueness. Humans are primates, and thus it is the challenge of evolutionary research to explain their emergence exclusively through the mechanisms of natural selection. The main subjects of research being discussed are taxonomy, functional, constructional, and evolutionary morphology, taphonomy as well as paleoecology and paleogenetics.

Within a multidisciplinary and multifaceted approach, paleoanthropology tries to decipher the adaptive problems that have been important in human evolution. This chapter outlines biological human evolution from the emergence of primates to the origin of anatomically modern humans. The main discussions concentrate on evolutionary trends within nonhuman primates, the adaptive problems that the australopithecines faced living in tropical environments as large, ground-dwelling mammals, the evolution of habitual bipedality, the nutritional change from herbivory to carnivory, and the increase of neuronal complexity (encephalization) within the genus Homo.

Finally, the taxonomical problems within our genus and the Eurasian dispersal of an early Homo are discussed on the basis of the actual fossil record. At present, the most debated paleoanthropological problem is the origin of modern humans. The competing models, the ‘recent African origin model’ and the ‘multiregional model’, are discussed thoroughly. A special section debates the image and fate of the Neanderthals, also taking recent aDNA results into consideration.