Final answer:
The 'Out of Africa' theory suggests that modern humans evolved in Africa from ancient hominids and then dispersed across the globe, replacing other human species. This theory is based on evidence from fossil records and genetic studies.
Step-by-step explanation:
The 'Out of Africa' theory is a widely accepted concept in biology that provides an explanation about the origins of humans. According to this theory, modern humans evolved in Africa from ancient hominids around 200,000 to 150,000 years ago. These early modern humans then migrated out of Africa and replaced all other human species in Europe, Asia, and other regions. The theory is based on various forms of evidence including fossil records and genetic studies, which show that the greatest genetic diversity among modern humans is found in Africa. This suggests that humans have been evolving in Africa for a longer period than anywhere else in the world.
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