Biologists say that behavior is ultimately determined by natural selection.
This is because genetic structures are constructed according to the mental processes and learned patterns and responses to different environments.
As Richerson and Boyd, authors of Not By Genes Alone: How Culture Transformed Human Evolution, note: physiological changes that shape behavior are evolutionary.
Take bird migration, for instance.
Instead of passing winter in harsh environments, birds have acquired their migratory behavior according to evolutionary physiological reactions.
The brain has formed evolutionary strategies across time to send hormonal signals that trigger annual migration to warmer climates.
So, while genes may determine the traits and behaviors best suited to the environment, the environment has helped shape these genes.
Where does culture come into play?
Culture is part of the environment, especially where humans are concerned.
Culture Drives Human Evolution
Taking the environment’s impact on evolution a step further, in a study by the University of Maine, culture was found to drive human evolution even more so than genetics.
According to the 2021 study by researchers, Tim Waring and Zach Wood, humans adapt to their environment and challenges in their environment via culture – in the form of learned knowledge, skills, and practices –more effectively and at a faster pace than through genetics.
One reason for this “special evolutionary transition” is that the cultural transfer of knowledge is flexible and fast when compared to genetic transfer.
Waring notes that:
“Gene transfer is rigid and limited to the genetic information of two parents, while cultural transmission is based on flexible human learning and effectively unlimited with the ability to make use of information from peers and experts far beyond parents.”
This results in a stronger adaptation via cultural evolution than genetic evolution allows.
The researchers also argue that culture’s group-oriented nature produces more group-oriented evolution as well.
Ways in Which Humans Have Evolved
How have humans evolved via culture?
Humans have adapted in several key ways over the millennia.
- Capacity for social learning
- Predisposition to be cooperative
- Capacity to collaborate
- Diminishing aggression
Genetics and culture work together to adapt behaviors, but as Waring and Wood’s research suggests, culture is becoming even more influential on the evolution of human behavior.
As Waring concludes:
“This research explains why humans are such a unique species…We are slowly becoming ever more cultural and ever less genetic.”