Transcript Chapter 11
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!