Barriers to diffusion

Physical barriers in nature:


rivers, oceans, lakes, and mountain ranges.
Cultural


religious beliefs.
language



impedes the easy flow of ideas and fads from the
United States and English-speaking Canada to
French Canadians in Québec.
Political boundary can impede or slow down the
dissemination of disease.
Economic factors –

people in certain places cannot afford to purchase a
new commodity or technological innovation.
Types of Diffusion

Expansion Diffusion – idea or
innovation spreads outward from
the hearth




Contagious
Hierarchical
stimulus
Relocation Diffusion- migrants bring
an idea/innovation physically
Worldwide, there are 1.4
billion followers of Islam
There are
between 5 –
7 million
Muslims in
the United
States
Diffusion of Islam
630 – 1600 AD




Hierarchical Diffusionideas/artifacts spread
between larger places
or social elite
later to smaller places
or less prominent
people
Fashion trends
Cell phone use in the
early 1990s
Music and Clothing (hierarchical
diffusion)


New clothing and
music fads, for
example,
spread quickly among
major world cities
such as New York, Los
Angeles,
London, Paris, and
Tokyo.
Only later do they
filter down the urban
hierarchy,
Starbucks.. They're everywhere
Contagious Diffusion



All individuals and
areas outward
from the source
region are affected
Term implies
direct contact
Usually associated
with disease
Distribution of
West Nile Virus:
Humans, Birds, &
Mosquitos, 2001
Diffusion of
Africanized
Bees after
their arrival
to Brazil,
South
America
Relocation Diffusion



Spread of culture through physical
movement
Language, religion, food
preferences
Can show spotty spatial distribution
Hmong Refugees from Laos
Spanish and Portuguese Colonies
Stimulus Diffusion (trans cultural)


Takes part of an idea to create an
innovative product
Computer keyboards, Cherokee
writing system, gang culture
fashions, Siberian reindeer herding.