10.5 Evidence of the migration of modern human populations

What is the Out of Africa hypothesis as supported by fossil evidence?

The model stating that Homo sapiens evolved in Africa about 300,000 years ago from Homo heidelbergensis, after which some groups left Africa, spread across the world, and successfully replaced existing populations of other hominin species.

What is Mitochondrial DNA (mtDNA) and how is it inherited?

DNA that is inherited strictly from the mother, and because it does not undergo any genetic recombination, it accumulates mutations at a highly constant rate.

How is mitochondrial DNA used to determine evolutionary divergence?

The greater the total number of mutations identified between the mitochondria of different species, the greater their divergence in evolution.

What does human genetic diversity show about modern African populations?

There is significantly greater diversity in the mtDNA of modern African populations (dating back 300,000 years) than the rest of the world's populations (who migrated 70,000 years later), serving as a textbook example of the founder effect.

What does the timeline of Aboriginal Australian migration show?

Homo sapiens (Indigenous Australians) arrived on the Australian continent at least 60,000 years ago, interbreeding with Homo neanderthalensis and Denisovans along the way.

What cultural outcome resulted from the long evolutionary history of Indigenous Australians?

It created a deeply embedded, incredibly strong connection to country and physical place over thousands of years.