29 January 2007

Rave: Wade's "Before the Dawn"

for anyone interested in human origins
this is a must-read survey of recent literature
with lots of insights i'd missed

most vivid map:
descendants of just 150
african emigrants c50k bc
colonised the entire rest of the world
quickly boating across south asia
then north crosscountry by 30k bc

looking at their shared behaviors
wade suggests the emigrants might have said
'tic' for finger/counting
'ma' for hand

wade argues that territorial wars
had claimed some 10% of each generation
from when we were chimps
to when we finally settled down into villages

he suggests the most dramatic social change
since the chimp days
was human pair bonding
replacing alpha-males-with-harems
(i'd speculate this must have begun
with informal sleeping partners
sharing small temporary shelters
with loyal partners gradually
earning social status)

wade is wrong, i'm sure, in blaming
the degradation of our sense of smell
on agriculture reducing selection pressures
it's too broad to be that recent
(i've placed it with fire 2M years ago
as cooked foods introduced
an entirely new palette of flavors)

he dates long hair to 200k bc
with the critical factor
the ability to keep it groomed
(which stone tools could trim hair?
which could shave skin smooth?)
he imagines ungroomed heads
have been ostracised that long

he makes a plausible case
that proto-indo-european
got its start with agriculture
in turkey-iraq-iran
10,000 years ago
then a second wind
from west european horsemen
4000 years later

some interesting stats from iceland
suggest most family trees quickly go extinct
and average generations there are 30 years
(more for men, less for women)


14M BC: orangutan/gorilla split
7M BC: gorilla/chimp split
6M BC: global cooling, African drought
5M BC: human/chimp split (pop 75k) chimps stay in trees, defending fruit-tree teritories

4.4M BC: bipedal vegetarian australopithecines
2.5M BC: forests retreat; omnivorous tool-maker homo habilis
1.8M BC: homos erectus and neanderthal emigrate during warm interlude
1.7M BC: homo ergaster loses body hair, skin blackens, males shrink, fathers care for infants? tubers cooked?

1.5M BC: chimp/bonobo split
500k BC: homo heidelbergensis
465k BC: human/neanderthal split
350k BC: mousterian toolkit of neanderthals

200k BC: long hair? foxp2 mutation?
195k BC: modern brainsize at kibish
150k BC: mitochondrial Eve?
140k-40k BC: genetic Adam

135k BC: dog/wolf split???
125k BC: first neanderthals, west of Urals
100k BC: global warming, anatomically modern humans
95k-11k BC: homo erectus on flores?

87k-37k BC: M168 mutation on Y chromosome
75k BC: global cooling
74k BC: anomalous shell necklace
70k BC: body lice genetics suggest tailored clothing

65k BC: eurasian eve?
55k-45k BC: U5 mitochondria in europe
pre-50k BC: cannibalism hinted by gene
50k BC: behaviorally modern humans (150 of total 5000 enter asia?) modern language abilities; warm window

50k-10k BC: 10% of each generation KIA
45k-33k BC: neanderthals displaced in europe
44k BC: african cultural revolution; australia occupied
43k BC: europe invaded by modern humans w/aurignacian toolkit

40k BC: dog domesticated in east asia?
40k BC: chatelperronian toolkit (neanderthal anomaly?)
40k-30k BC: gracilisation via pedomorphism
38-33k BC: M173 Y chromosome (aurignacians?)

35k BC: microcephalin brain gene (60k-14k)
30k BC: chauvet cave art
26k-19k BC: gravettians hunt mammoth
23k-18k BC: M170 Y (gravettians?)

20k BC: glaciers depopulate europe, siberia
19k-14.5k BC: solutreans hunt horse, deer
18k-13k BC: Last Glacial Maximum (pop 1M-10M)
17k BC: ice age ends; siberians domesticate dogs

16k-13k BC: M242 Y
16k-9k BC: magdalenians hunt reindeer
16k BC: gravettian mammoth-bone houses
15k BC: egalitarian warlike tribes supplanted by gracile property-respecting villagers; V and H mitochondria dominate europe

13k-10k BC: warming
13k-9.5k BC: natufians harvest wild grains w/sickles
13k BC: dog domesticated?
12k BC: dog bone in germany

10.5k-9k: younger dryas cold snap
10k BC: wild einkorn cultivated
8.5k BC: domesticated einkorn
8.4k BC: domesticated emmer wheat, rye, barley

8k BC: mongoloid skulls in china
8k BC: end of ice age; sheep and goats domesticated; J mitochondria in europe
7k BC: hittite splits from PIE
5k BC: tocharian splits from PIE

5k BC: hybrid wheat in Iran
4k BC: ASPM brain gene
4k BC: european languages diverge from PIE
4k BC: horse domesticated north of black sea

4k-3k BC: funnel beaker culture breeds cattle, drinks lactose
3k BC: lactose tolerance
catal hotuk, M172, LBK pots