174 The Dispersal of Modern Humans

Key Idea: Hominins evolved in Africa and dispersed throughout the globe. Waves of migrations of Homo sapiens probably occurred from as early as 180,000 years ago. The map below shows a suggested probable origin and dispersal of modern humans throughout the world. An African origin is almost certain, with south eastern Africa being the most likely region. Evidence generally supports continual waves of migrations of H. sapiens, perhaps from as early as 180,000 years ago. The dispersal was affected at crucial stages by the last glacial, when ice sheets covered much of Europe and ‘land bridges’ formed as a result of the associated drop in sea level. Recent evidence suggests that island-hopping and coastal migration may also have been important, e.g. for the movement of people into Indonesia. The late development of boating and rafting technology slowed dispersal into Australia and the Pacific. New Zealand was one of the last places on Earth to be populated. (On the map, ya = years ago.)

1. (a) Study the map above and suggest why humans reached Australia before they reached Western Europe, even though Australia is further away from their point of origin:

(b) Suggest why New Zealand was one of the last land masses populated by humans:

Iceland

Cro-Magnon 30,000 ya

The first modern humans appear in Europe 40,000 - 35,000 years ago

Jebel Irhoud (Morocco) 315,000 ya

Recent finds from Morocco dated at 315,000 years suggest that AMH emergence may have involved the whole of the African continent.

Klasies River Mouth 120,000 - 84,000 Skuhl 101,000 - 81,000 ya

Qafzeh 120,000 - 92,000 ya

Afar, Ethiopia 160,000 ya

Omo 130,000 ya

The Flores fossils, at 38,000 - 13,000 years suggests there may have been waves of movement into Indonesia. The earliest dating in East Asia for modern humans is 67,000 years ago from Liujiang County in southern China

Malakunanja II 50,000 ya

Border Cave 115,000 - 62,000 ya

Australia has been occupied for at least 50,000 years. New genomic evidence (yet to be corroborated) indicates that the ancestors of Aboriginal Australians left Africa about 24,000 years before the later migration wave that populated Asia and Europe.

Lake Mungo 31,000 ya

New evidence suggests first permanent Maori settlement in New Zealand only 700 years ago (not 1200 years)

The movement of humans into new parts of the world has often been cited as the major reason for the extinction of the many large animals that lived around 40,000 to 15,000 years ago, such as the woolly mammoth. The loss of megafauna is often correlated with the arrival of humans. However, other evidence suggests climate change near the end of the last glaciation was the major factor in the extinction of these animals. Also, good evidence of mammoth hunting is relatively difficult to find, suggesting humans did not play a big part in their extinction. As with many aspects of studying ancient humans, the answer is open to debate.

Earliest modern humans travelled across what is now the Bering Strait, via the temporary ice-age land bridge to the Americas between 20,000 and 15,000 years ago

Hawaii

The latest mtDNA analysis suggests three migrations into the Americas. The first 15,000-18,000 years ago along the western coast into South America, the second 10,000 years ago into North America, and the third 4,000 years ago along the northern coast into Greenland.

Polynesia populated progressively between 4500 - 700 years ago

Iceland

A coastal Atlantic route has also been proposed for the populating of the Americas. In this model, inhabitants of Western Europe would have travelled along the southern margins of the Atlantic sea ice to the Americas. The argument is based on similarities between the Solutrean tool culture of ice age western Europe and the tool culture of the Clovis people of America (above).

KEY

Region covered by ice or tundra in the last ice age

Over land migration route

Coastal migration / island hopping

2. Using examples, discuss the importance of land bridges and glaciations in the global dispersal of modern humans: