ANT human origins exam 1
Card Set Information
ANT human origins exam 1
theory- narrative in structure and language, thus theories are amended to literary anaylsis
hero folk tale
morphology of a folk tale
31 stages found in all tales
coming down from trees
walking on two legs
growth and brain size
culture, symbols, etc
human evolution as a narrative
Landau 9 stages
1. initial situation/
6.fairy godmother/ natural selection
8.tested again/ leaving africa
9.triumph/ modern humans
belief or perception of purposefulness in nature
progressive evo in a unfamiliar fashion
out of Africa
1. longer limbs
2.increase body and brain size
3. more meat (omnivore diet)
4.sophisticated stone tools
Variety of species from one ancestor occurs when a variety of habitats are available.
Human origin as a bush NOT tree
Jean Baptiste Lamarck
organisms respond to environmental factors in response to felt needs.
-> law of use and disuse
acquired changes are passed on
: giraffe who stretch his neck to reach the leaves at the top of the tree, eventually reaching them with a longer neck.-- trait passed to kids
principle of geology
unformitarianism-"the present is like the past"
pop. continues to grow but food supply remains the same.
- limits in food supply keep advances in pop. size in check.
Alfred Russell wallace
"on the tendencecy of varities to depart indefinitely from the original type"
Natural selection consequences
: four condi.
----------survival of the fittest- differential repro. success
: mechanism of inheritance
mutationist school v.s the selectionist school
the modern synthesis
- genetic drift
moth study in U.K
evolution in action
change in gene frequency over time
drug- resistance TB in russia
rough skinned newt
human induced changes- big horn sheep and atlantic cod
human skin color- folate and vitamin D
tay-sachs and TB
bio. species concept
- donkeys and horse breed, have sterol offspring
- interbreed of diff but similar species
the splitting of a lineage into isolated sub pop.
general, gradual change in a lineage
diversity of one species that gradually changes through time.
one population of one species became two species while in the same geographic region with no physical separation
speciation occured in different regions.The key with allopatric speciation is geographical separation
evolution *within* a gene pool of a population of interbreeding species-mates.
macro- evo debate
separated gene pools (reproductively isolated populations
>evolutionary trends that affect
periods with no change/ or little than periods with huge changes
------seen in genetic mutatuions
>slowly over time with little variations occuring
what are factors that influence the evolution of new species????
1) Inherited properties (historical constraints)
2) The biotic context
3) The physical context
The biotic context
the red queen hyp.
- have to run to stay in once place> AKA keep evolving to stay alive
>predator- prey interactions
-an adaptation in one species (predator) may cause selection pressures in another species (prey)
split by geography they eventually will not be able to interbreed.
- geographic changes that causes areas of land to be dramatically different even though they are relatively close
: Rain shadow and local habitat changes
Habitat Hypothesis (Elisabeth Vrba)
-survival and adaptation
- eco goes through changes that can result in mass extinction
Variability selection in hominin evo
Potential for dispersal & Proneness to extinction
Bipedality->encephalization (increase in brain)->
Direct vs. indirect methods
1. direct methods date objects themselves . ex
2. in direct methods are applied ro something assoc. with the fossil or artifact. ex
relative dating techn.
faunal correlations and paleomagnetism
abso. dating tecn.
1) Some action sets a clock to zero
2) Radioactive isotope (parent atom) decays at a steady rate
3) Product of radioactive decay accumulates (daughter atoms)
*(age determined by determining the ratio of daughter atoms to parent atoms)
radio-carbon or c-14
Range + 200-50,000 years ago
: Contamination, Calibration
-dates organic material
- c-14 naturally occurs but unstable isotope of c-12
- the two isotopes occur in a constant proportion in nature, are absorbed by living things
- once an organism dies, no new carbon is absorbed into it, c-14 then starts to decay
Range 100,000 ya to 2 billion years
: Error estimates are large
-relies on radioactive decay of isotopes found in indigenous rocks
- usually decay of k-40 to Ar-40
- when rock is heated all Ar-40 is released as gas (eruption), clock sets to zero
- when cooling Ar-40 begins to gather b/c of potassium break down
dates gather but comparing accumulated Ar-40 to remaining k-40