In this chapter we have explored our human journey as a member of the genus Homo, following a trail of adaptations and change that ultimately led to us. First on the scene were the australopithecines, who were already walking on two feet and paved the way for the evolutionary changes and cultural achievements that were to follow. A colder climate with drastic changes in climate were associated with an increased reliance on cooked meat, which may have contributed to a growing brain. A brain with highly developed cognitive skills gave humans the capacity to solve problems and create tools that enabled better hunting and survival skills. Adaptations provided H. ergaster and H. erectus the ability to walk and run longer distances, to more effectively track and follow game, and to explore nearby continents.
Genetic information provided by mtDNA indicates that all humans shared common ancestors who lived in Africa 200,000 years ago. Studies of genetics shows examples of coevolution and how even small organisms such as lice can shed light on the human story. The rise of agriculture created new challenges for humanity, with evolutionary mismatch still impacting people today. From the earliest toolmakers to the cave art of the Upper Paleolithic to the modern computer age, the predominant theme of human history has always been about change. The ability to adapt to this change is why humans are still here. Humans’ evolutionary story, however, does not end with the emergence of the species. Today humans are faced with numerous challenges as they adapt to an increasingly changing environment as a result of climate change, loss of habitat, and decreasing biodiversity. In 2020, Darwin’s theory of natural selection played out in real time as people began an arms race with a mutating and evolving COVID virus. Evolutionary change is not something that happened to people just in the past—it is very much still happening today, and it will continue to be part of the future.