Chapter 11
The Lethal Gift of Livestock
Farmer Power
• Farmers have greater numbers than
•
•
•
•
hunter/ gatherers
– 10 or 100 to 1
Own better weapons and armor
Have more powerful technology
Have centralized governments with
literate elites
– better able to wage wars of
conquest
Breathe out nastier germs.
Major Killers
• Major killers of humanity throughout recent
history are all infectious diseases that
evolved from diseases of animals
–
–
–
–
–
–
–
Smallpox
Flu
Tuberculosis
Malaria
Plague (pictured)
Measles
cholera.
Disease victims in war
• Until WWII, more victims
of war died of disease than
battle wounds.
• 95% of Native Americans
died from diseases brought
by Europeans.
• Why not the other way
around?
• Europeans had the animals
and the large populations
that produced the diseases.
How Diseases Spread
• Passively
– Salmonella
• insect vector
–
–
–
–
Malaria
Plague
Typhus
Sleeping sickness
• Lesions
– Syphilis
– Smallpox
How Diseases Spread
• Coughing
– Flu
– Cold
– Whooping
cough
• Diarrhea
– Cholera
How Diseases Spread
• Killing humans is
an unintended
byproduct of
disease growth and
spread
How We Respond to Diseases
• Fever (bake out microbe)
• Immune response.
Children with AIDS
– This may give us lifelong immunity
(measles, mumps, rubella, pertussis,
smallpox)
– or not, if microbe evolves quickly
(flu, malaria, sleeping sickness,
AIDS)
• Natural selection.
– Not everybody dies, resistant genes
selected for in population.
Epidemic Diseases
• Epidemic diseases spread
Smallpox
quickly to an entire population
• Run their course quickly
• Result in either death or
resistance.
• Tend to be restricted to humans.
– ex: measles, rubella, mumps,
pertussis, smallpox
Epidemic Diseases
• Flu killed 21 million
Plague, 14th Century
Europe
people at end of WWI.
• Black Death killed 1/4 of
Europe's population
between 1346 and 1352.
• Disease dies out if
population is under a half
million because everybody
has been exposed and is
either dead or resistant.
Epidemic Diseases
• Disease only survives
with travel between
populations or
between uninfected
pockets within a
population.
• These diseases cannot
sustain themselves in
small populations of
hunters/gatherers
Diseases in Small Populations
• Dysentery from a sailor
on a whaling ship killed
51 of 56 Sadlermiut
Eskimos in 1902.
• Then disease died out.
Diseases in Small Populations
• Diseases in small populations
restricted to
– ones that can live in animals:
• yellow fever
– ones that take a long time to
kill:
• leprosy
– ones that humans don't develop
immunity to.
• worms and parasites
Leprosy
Agriculture and Disease
• Why did agriculture
launch the major
infectious diseases?
– high human
populations
– Sedentary life among
sewage
– Close proximity to
herd animals
Disease Transfer from Animals
• Four stages of animal to human disease transfer:
• 1) diseases directly from animals.
– Don't get transmitted human to human
– ex: brucellosis from cattle, leptospirosis from dogs
• 2) Does transfer human to human, but dies out
– ex: Fort Bragg fever in 1942
• 3) Transfers human to human but not yet long-established
– ex: Lyme disease, AIDS
• 4) long established epidemic diseases.
– Diseases evolve to effectively work in new host
– ex: syphilis
Role of Disease in Conquest
• Diseases played huge
part in conquest of New
World.
• Hispaniola had 8 million
inhabitants in 1492, zero
by 1535.
• There were estimated 20
million Indians in USA
before European
diseases. 19 million
died
Role of Disease in Conquest
• Were 20 million in
Mexico, reduced by
disease to 1.6 million.
• With 20 million, why
not more infectious
diseases?
• Answer: No large
domestic animals.
Chapter 12
Blueprints and Borrowed Letters
Writing
• Writing marched together
with weapons, microbes
and centralized political
organization as a modern
agent of conquest.
• Why did only some
peoples and not others
develop writing, given its
overwhelming value?
Pizarro’s conquest
of Atahuallpa
Strategies for Writing
• Three strategies for writing:
• 1) logogram
– One symbol stands for a word
• Ex: Chinese
• Syllabary
– One symbol stands for a syllable
• Alphabet
– One symbol stands for a basic sound
Chinese
Invention of Writing
• Writing invented independently
Egyptian hieroglyphics
just four times
– Mesopotamia (3,000 BC)
– Egypt (3,000 BC)
– China (1300 BC)
– Mexico (600 BC)
• All others borrowed, adapted or
inspired by these systems.
Invention of the Alphabet
• Alphabet invented just once: by
Semites starting 1700 BC
• Three steps in Alphabet development:
– Started with 24 Egyptian
consonants, discarded all
logograms
– Ordered the consonants in fixed
sequence
• Greek: Alpha, Beta, etc. gave
Alphabet its name
– Invented vowel symbols
“Blueprint” Copying
• “Blueprint” copying of
Semitic alphabet (with
modifications) led to these
alphabets:
– Aramaic, Southeast Asian
– Persian, Phoenician
– Arabic, Greek
– Hebrew, Roman
– Indian, Cyrillic
“Idea Diffusion”
• Writing systems have also
Sequoyah
spread by “idea diffusion”
• Ex: Cherokee Indian named
Sequoyah, 1820s
– Illiterate
– Devised a writing system for
Cherokee language
– Was a syllabary of 85
symbols
– Based only on knowledge that
English could be written
“Idea Diffusion”
• Other writing systems
originated by “idea
diffusion”:
– Korean
– Celtic Ogham
– Polynesian
Korean alphabet: 24 letters
Early Writing
• Early writing was like shorthand
– For record keeping
– Required Scribes to write
• Arose in stratified societies that could
support bureaucrats
• Hunter/Gatherers
– No use for scribes
– No extra food to feed scribes
• Since most societies acquired writing
Egyptian scribe
from others, isolated complex societies
less likely to have it:
– Incas
– Sub-Saharan Africa
– Native Americans in Mississippi valley
Chapter 13
Necessity’s Mother
Technology
• Why did technology evolve at
different rates on different
continents?
• Many inventions are the mother
of necessity
– Without a clear need
– In search of practical
application
– Or their application evolves
• Automobiles were not
“needed” at first: toys of rich
• Phonograph was not for
music: Edison objected!
Tinkering
• Inventors have to
tinker for a long time
for inventions to be
accepted
– TV
– Cameras
– Typewriters
Inventions
• Inventions rest on a long history
of previous inventions:
– James Watt’s steam engine
(1769)
– Was based on Newcomb’s
(1712)
– Which was based on Savery’s
(1698), etc.
• Therefore, if not Watt, would be
someone else
Acceptance by Society
• Inventions depend on society being
ready to accept or exploit the invention
• Four Factors influence acceptance:
– 1) economic advantage
– 2) social value and prestige
– 3) vested interests
• QWERTY typewriters designed to
slow down typing for 1870
typewriter
• Once widely accepted, can’t change
although very inefficient
QWERTY keys once an
advantage
– 4) ease of observing advantages
• English immediately saw
advantage of cannons
Resistance to Technology
• For any given society, most
inventions come from elsewhere
– either accepted or not
• Many reasons societies resistant to
technology adoption
• Each continent has more and less
resistant cultures
• Reception to technology varies
over time in the same culture
– Japan adopted firearm technology
in 1540s
– improved them and became best in
the world
– then banned them by 1600s.
Acceptance of Technology
• Societies accept
technologies because:
• They see an advantage
• Conquered by others
with technology
• Invention spreads by
“Idea Diffusion”
British Porcelain China
– Porcelain china
manufacture in
England
Autocatalysis
• Technology begets more
technology: Autocatalysis
– Current rate very fast
• Reasons:
– Advances depend on
previous mastery of
simpler problems
• Ex: Metallurgy from
copper to iron
– Combinations of
technologies make new
technologies possible
• Ex: Printing Press
Technology Development
• Three Factors in
•
•
•
•
Technology Development:
1) Time of onset of food
production
2) Lack of barriers to
diffusion (isolation)
3) Human population size
Huge advantage of Eurasia
in all three areas!