Lecture: September 2: Economic Growth Since Deep Time
Lecture: September 2: Economic Growth Since Deep Time
U.C. Berkeley Economics 101b, Fall 2005
The East African Plains Ape Becomes Human
- Very big brains
- Tools
- Culture
- Manipulation of environment
(Some) Humans Move Out of Africa
- 50000 years ago?
- No signs of interbreeding with other non-African proto-human populations
- Genetic differences?
- 2000 generations is not a long time for Uncle Charles Darwin to work
- Facial features, hair, lactose-tolerance, sickle cell and anemia resistance, Tay-Sachs
- And, of course, melanin: rickets, vitamin D, melanoma
- Skin color as a marker of slave status in the Americas: it kept slavery going for centuries after indentured servitude (which did not use skin color as a marker) broke down
- Woolier and unsubstantiated stories:
- Jared Diamond on how people in Papua New Guinea are smarter than the rest of us
- In northern latitudes keeping warm is important: selection for dumpy and less athletic body types?
- But don't go there: evolutionary behavior is still nothing more than a source of just-so stories, and has been a source of immense ignorance and terror in the past
- The way to think of it, I have been told, is that there is less genetic variation in the entire human race than in a single baboon troop
Hunter gatherers * Pretty ferocious--even East African Plains Apes of two million years ago could drive hyenas from their dens * Sophisticated Cro-Magnon technology * Sophisticated Cro-Magnon culture--doing a lot of things that mark them as fully human * Life was nasty, brutish, and short--but athletic * Cro-Magnon hunter-gatherers * Average menarche at 16? * Life expectancy of 25? * Seven pregnancies to term? * But infinitesimal population growth means ferocious infant mortality * But they were buff: adult male heights of 5'8" or so
Neolithic Revolution
- Herd animals to be domesticated
- Plants with big seeds
- Wheat
- Rice
- Corn--an amazing plant
- Agriculture sees like an enormously good deal at the start
- Well-nourished and easy-living agricultural populations expand rapidly
- Farm sizes diminish
- And Thomas Robert Malthus shows up
- Agriculture allows human race to grow from ca. 3 million (or less) in 10000 BC to ca. 170 million (or so) in 1
- Agriculturalists stomp hunter-gatherers, and usually herdsmen
- Exception: people on horses with bows can hold their own
- In fact, people on horses with bows can sometimes do much more than hold their own: Atilla, Temujin--until reliable firearms
What Is Agricultural Life Like?
- Nasty, brutish, short--and definitely not buff
- Menarche at 18?
- Life expectancy of 25?
- 6? pregnancies to term
- Huge childhood mortality--population growth is once again glacial--except for initial settlement phases
- Alleviation of Malthusian misery (partial) by European household marriage or Asian lineage family
- Psychological stress produced by these social institutions--telling your daughter she can't marry her boyfriend until he has a farm, or telling your younger brother he can't have a wife...
- Agriculturalists definitely not buff--adult male heights of 5'2" or so
- Plus
- Agriculture means thugs with spears--rulers and warrior castes
- Agriculture means thugs with pens--star watchers who keep records and can tell you when to plan become priests
By the Yeqr 1, the Human Race Was Biologically and Technologically Successful--But Pretty Miserable
