chapter 11 the lethal gift of livestock. farmer power farmers have greater numbers than hunter/...
TRANSCRIPT
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.
– 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.
Children with AIDS
Epidemic Diseases
• Epidemic diseases spread 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
Smallpox
Epidemic Diseases
• Flu killed 21 million 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. Plague, 14th Century
Europe
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 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.
Egyptian hieroglyphics
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 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 writtenSequoyah
“Idea Diffusion”
• Other writing systems originated by “idea diffusion”:– Korean
– Celtic Ogham
– PolynesianKorean 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 from others, isolated complex societies less likely to have it:– Incas– Sub-Saharan Africa– Native Americans in Mississippi valley
Egyptian scribe
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
– 4) ease of observing advantages• English immediately saw
advantage of cannonsQWERTY keys once an advantage
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”– Porcelain china
manufacture in EnglandBritish Porcelain China
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!