ABSTRACT
Studying humans includes the study of our biology. Humans, by virtue of being living organisms, share certain fundamental characteristics of all life on Earth: we are made of cells—and these cells are organized into tissues, organs, and systems—we reproduce and through this process affect the genetic variation within and among populations, we acquire and process energy to support our bodily functions, we undergo a developmental life cycle with different biological stages, and we are linked to the rest of life on the planet through common ancestry. In the most recent history of our species, we have also relied on cultural institutions that allow us to preserve and transmit information and technology so that these have become essential to the way that humans survive in their environments. Many of these cultural institutions in the form of customs and practices (or even formal constructs such as laws) can affect how biological humans interact with their environments, and the result can generate biological variation among human populations that can be measured in genetic variation. Whether human societies do it consciously or unconsciously, customs and practices can have a direct effect on the Darwinian concept of “fitness”—the relative success in surviving to adulthood and producing children who themselves can be successful.
