The video above is from the January 2013 iPad edition of National Geographic magazine. Find more interactive content, photos, and videos in the iPad version of National Geographic magazine.
Modern humans—Homo sapiens—began their migration out of Africa some 60,000 years ago. Our early ancestors kept exploring until they spread to all corners of the Earth. How far and fast they went depended on climate, the pressures of population, and the invention of boats and other technologies. Less tangible qualities also sped their footsteps: imagination, adaptability, and an innate curiosity about what lay over the next hill.
Today, geneticists are doing their own exploring. Their studies have led them to a gene variation that might point to our propensity for risk-taking, movement, change, and adventure. This gene variant, known as DRD4-7R, is carried by approximately 20 percent of the human population. Several studies tie 7R (and other variants of the DRD4 gene) to migration. (Genetics is complex, however. Different groups of genes interact and yield diverse results in different individuals. DRD4-7R probably influences, not causes, our tendency toward “restlessness.”)
Review “The Global Human Journey” video, then discuss geography and genetics as posed by queries in the “Questions” tab.
Follow the arrows and describe the path of early human migration across the world. Where are the oldest human settlements outside Africa? Why do you think these areas were settled first?
Consider the physical geography encountered by our ancient ancestors. Do you think early humans followed any geographic patterns in their migration out of Africa?
Migration to remote island groups, such as the Philippines or the islands of Polynesia, appears to have been one of the final stages of global human migration. Can you think of any reasons for this?
The so-called "restless gene," DRD4-7R, has been linked to the human tendency toward risk-taking, including migration. Can you think of other adventurous behaviors that may be influenced by "the restless gene"?
Term Part of Speech Definition Encyclopedic Entry ancestor Noun
organism from whom one is descended.
all weather conditions for a given location over a period of time.
Encyclopedic Entry: climate gene Noun
part of DNA that is the basic unit of heredity.
scientist who studies the chemistry, behavior, and purposes of DNA, genes, and chromosomes.
Homo sapiens Noun
(200,000 years ago-present) species of primates (hominid) that only includes modern human beings.
movement of a group of people or animals from one place to another.
total number of people or organisms in a particular area.
the science of using tools and complex machines to make human life easier or more profitable.