L24: Human Biogeography Flashcards
What is conservation biogeography?
The application of biogeographic principles to the conservation of species (Gillson et al., 2015).
What concept is often discussed when talking about humans as a society?
The super organism concept (Malhi, 2017).
The interconnectedness of the human population.
Every hour, 10,000 people join the global population.
What is the pleistocene?
(2588000 to 11700 years ago)
Here, the earth experienced intensification towards climatic cooling (the ice age!)
Culminated with a series of glacial and interglacial cycles and major geographic shifts in habitats across Africa, including mesic grassland, woodland and savanna ecosystems as well as the more xeric habitats.
How many potential dispersal routes are there for the dispersal and range expansion of Homo erectus and Homo sapiens?
3
What were the 3 potential dispersal routes for the dispersal and range expansion of Homo erectus and Homo sapiens?
- Northwestern passage across Gates of Hercules (Strait of Gibraltar).
- Northeastern along the Nile Valley and across the Sinai into the Arabian Peninsula.
- Southeastern across the Gates of Grief (Red Sea).
What was the geographic range expansion of homo sapiens from African homeland to its eventual global distributions strongly influenced by?
Contemporary landscapes, seascapes, and climate.
Very influenced by the climatic upheavals that marked the 2 million year record of the Pleistocene.
Potential barriers of the Northwestern passage across Gates of Hercules (Strait of Gibraltar)?
Sahara was an expansive desert that prevented early humans from humans from reaching the northwestern passage.
Potential barriers of Northeastern along the Nile Valley and across the Sinai into the Arabian Peninsula?
During interglacial period Sahara with more mesic conditions allowed a corridor for dispersal along the Nile Valley.
But! 120000 years ago H sapiens-glacial cycle caused a change in climate and widespread aridification of the Arabian Peninsula. The population then went extinct!
Potential barriers of Southeastern across the Gates of Grief (Red Sea)?
Glacial conditions lowered sea levels by approximately 100m!
Reaching the Arabian Peninsula 90000 years ago.
Episode of jump dispersal was followed by range expansion through diffusion along the coasts of the Arabian Peninsula.
How were the homo sapiens able to navigate from China to Australia?
There was a lowering of sea levels during glacial maxima of the Pleistocene which caused the exposure of continental shelves and the formation of dispersal routes across four regions of the eastern Pacific.
What is jump dispersal?
Dispersal that is accomplished by movement of individuals within a relatively short period.
What is diffusion?
A form of range expansion that is accomplished over generations by individuals spreading out from the margins of the species range.
Much slower than jump dispersal.
