Geographers and Models for AP Human Geography

Jared Diamond ( $1937-$ ): Guns, Germs, and Steel ( $1997$ ). Argued that Eurasian dominance resulted from geographic luck and environmental determinism, particularly latitudinal positions similar to the Fertile Crescent.
Carl Sauer ( $1889-1975$ ) and Julian Steward ( $1902-1972$ ): Sauer emphasized cultural geography where human activity imprints on the physical landscape; he was a critic of environmental determinism. Steward linked environmental influence to human adaptation and possibilism.
Alfred Wegener ( $1880-1930$ ): Hypothesized Continental drift ( $1915$ ), which was later supported by plate tectonics discoveries in the $1950s$ .

Ernst Ravenstein ( $1834-1913$ ): Laws of migration ( $1885$ ) stating most migration is economic, occurs over short distances in steps, and that rural dwellers are more migratory than urban dwellers.
Henry Carey ( $1793-1879$ ): Gravity model; interaction is proportional to the multiplication of two populations divided by the distance between them, leading to distance decay.
Thomas Malthus ( $1766-1834$ ): Predicted starvation because food production increases arithmetically while human reproduction increases geometrically.
Esther Boserup ( $1910-1999$ ): Argued population growth stimulates agricultural intensification and technology ( $1965$ ).
Warren Thompson ( $1887-1973$ ): The Demographic Transition Model (DTM) with $5$ stages ranging from Low Growth (Stage $1$ ) to Negative Growth (Stage $5$ ).
Abdel Omran: The Epidemiological Transition ( $1971$ ) detailing the shift from the Age of Pestilence to the Age of Degenerative and Man-Made Diseases as countries modernize.
Wilbur Zelinsky ( $1921-2013$ ): Model of Mobility Transition, connecting migration types to DTM development phases.
William Alonso ( $1933-1999$ ): Bid-rent curve; land price and demand decrease as distance from the CBD increases.

Alfred Mahan ( $1840-1914$ ): Sea Power ( $1890$ ); argued naval power leads to global dominance.
Friedrich Ratzel ( $1844-1904$ ): Organic theory; states require territory ( $lebensraum$ ) to survive, functioning like organisms.
Halford Mackinder ( $1861-1947$ ): Heartland Theory ( $1904$ ); control of the Eurasian "pivot area"/Heartland is key to world dominance.
Nicolas Spykman ( $1893-1943$ ): Rimland Theory ( $1944$ ); the Eurasian Rimland (not the Heartland) is the key to global power.

Marija Gimbutas ( $1921-1944$ ): Kurgan Hypothesis ( $1950s$ ); Proto-Indo-European language spread through conquest from Ukraine.
Colin Renfrew ( $1937-$ ): Anatolian Hypothesis ( $1987$ ); language spread peacefully through the First Agricultural Revolution from Anatolia.

J. H. von Thünen ( $1783-1850$ ): Isolated State ( $1826$ ); model based on transport costs and profit. Rings include: ( $1$ ) dairy/gardening, ( $2$ ) forests, ( $3$ ) grains, ( $4$ ) ranching.
Norman Borlaug ( $1914-2009$ ): Father of the Green Revolution; developed high-yielding varieties (HYVs) of crops like $IR8$ rice.

Walter Christaller ( $1893-1969$ ): Central place theory ( $1933$ ); explains settlement distribution via hexagons based on Threshold (minimum market) and Range (maximum travel distance).
Joel Garreau ( $1948-$ ): Identified edge cities ( $1991$ ) as autonomous economic loci on urban fringes, involving suburbanization and malling.
City Models: - Ernest Burgess ( $1886-1966$ ): Concentric Zone Model ( $1925$ ). - Homer Hoyt ( $1895-1984$ ): Sector Model ( $1939$ ) utilizing transportation corridors. - Harris & Ullman: Multiple Nuclei Model ( $1945$ ) and Peripheral Model (Galactic City). - Griffin & Ford: Latin American City Model ( $1980$ ). - Terry McGee ( $1936-$ ): Southeast Asian City Model ( $1967$ ). - Harm de Blij ( $1935-2014$ ): Sub-Saharan African City Model ( $1968$ ) with three CBDs.
John Borchert ( $1918-2001$ ): Identified five epochs of American urbanization driven by transport technology, from Sail-Wagon to High-Technology.

Alfred Weber ( $1868-1958$ ): Least Cost Theory; manufacturing sites are chosen to minimize costs in transportation, labor, and agglomeration.
Harold Hotelling ( $1895-1973$ ): Linear City Model ( $1929$ ); emphasizes locational interdependence for profit maximization.
August Lösch ( $1906-1945$ ): Profit Maximization ( $1954$ ); the Spatial Margin of Profitability is the zone where income exceeds costs.
Walter Rostow ( $1916-2003$ ): Modernization Model ( $1960$ ); a liberal model with $5$ stages of linear development.
Singer & Prebisch: Dependency Theory ( $1949$ ); structuralist view that global power relations limit LDC development.
Immanuel Wallerstein ( $1930-$ ): World-System Theory ( $1974-89$ ); global division of labor into core, semi-periphery, and periphery.