Where Does Human Physical Diversity Come From?
Center for Diversity and Inequality Research, ECU Department of Sociology
Overview
We are different physically from one another.
Where does this difference come from?
Out of Africa
It is generally accepted that modern humans
emerged in Africa from 200,000 to 140,000 years
ago.
Migration and Environmental Adaptation
From Africa, humans migrated to the far corners
of Europe and Asia. Non-Africans became
distinguishable from Africans around 110,000
years ago. Among Non-Africans, Caucasians
were distinguishable from Mongoloids (Asians
and arctic inhabitants) about 41,000 years ago.
With migration, adaptive traits (skin color, body
stature, eyebrow ridge) enhanced the
probability of survival to reproduce and were
consequently maintained in the gene pool.
Reproduction and Geographic Origin
The urge to reproduce perpetuates the human species. Humans tend
to mate with those in close proximity. With migration, people with
different traits occupy the same area. With mating, traits are
‘blended,” enhancing human diversity and blurring sociallyconstructed racial categories. Genetically, humans are 99.7% the
same. Three-tenths of one percent of human genetic variation is
attributed to physical traits grounded in environmental adaptation
that we call “race”.
Strength Through Diversity
Human diversity enhances resistance to disease and discourages
birth defects. Mating between individuals with traits common to
different geographical regions of origin enhances the resilience of
offspring and blurs the significance of race and ethnicity as social
constructions. Diversity enhances human adaptation, disease
resistance, and survival.
Check out http://www.pbs.org/wnet/facesofamerica/ to see and
hear celebrities talk about race and ethnicity in their lives.