The Advent of Biological Evolution and Humankind: Chance or Necessity?
The human lineage appeared around 7 Ma (mega-annum, million years before present) as the sister group of chimpanzees, our closest relatives. Thus, humans and chimpanzees are very similar, genetically speaking, though they differ in many conspicuous phenotypic, functional, and adaptive traits.
What was the cause of the appearance of humanity? Is it related to hazardous episodes? Or, is it the result of a necessity due to the fact that our nature endows a somehow adaptive superior capacity that justifies the human prevalence among all primates?
In this chapter we examine the components of chance and necessity in biological evolution. We will present the distinctive features of the human lineage and discuss to what extent the synapomorphic trait shared by the whole lineage of humans—bipedalism—can be considered a product of adaptive selection or random events. Finally, we introduce the current possibilities of analysis to characterize the origin of the derived features of Homo sapiens.
