anthropology final exam

fossil

mineralized remains or traces of animals, plants and other organisms

Fossil record

totality of all fossils

paleoanthropology

study of ancient humans based on fossil evidence, tools, and other signs of habitation

ideal conditions of fossilization

encased in lava, volcanic ash, tar or tree resin. Freezing or dry, arid conditions

date of last common ancestor of humans between chimp and humans

(6-7 MYA)

Facultative bipedalism

capable of walking or running on two legs under exceptional circumstances (obligatorily quadrapedal)

foramen magnum

“big hole” located on the inferior region of skull.

Illium

blade part of pelvis

how has placement of the foramen magnum changed with bipedalism

anterior (homo sapiens) and posterior (pan traglodytes)

how has the vertebrae changed with bipedalism

s-shaped (bipedal) and c-shaped (quad)

how has pelvis changed with bipedalism

short and bowl like (bipedal) and narrow/elongated (quad)

how is the fossil record biased

the conditions required for a fossil are very specific, inaccurate representation of all organisms that have lived on earth.

center of gravity

point at which entire mass of body weight is concentrated.

bicondylar angle

angle seen in bipedals. lower femur

feet in bipedals vs. quad

bipedals: arch, smaller hallux (big toe) and in line with other toes

quads: no arch, bigger hallux and divergent from other toes

Energetic efficiency model

bipeds evolved because being on two feet conserved energy.

how did the weather in africa change during late Miocene/early Pliocene?

became dryer and cooler. breakup of tropical forests

sahelanthropus tchandensis

6-7 MYA, Toros-menalla (2001), small face, small brain, intermediate foramen magnum, orthognatic, supraorbital torus

supraorbital torus

brow ridge

based on this class, which is earliest hominin

sahlenthropus tchadensis

aridpithecus ramidus

4.4 MYA, Found in Ethiopia (1992-1994), woodland environment, small brain, reduced canines, anterior foramen magnum

aridpithecus ramindus skeleton

reduced canine, anterior foramen magnum, arm not weight bearing, lower limbs had climbing adaptations (divergent hallux, grasping toe)

endocast

cast of inside of cranium

gracile

lightly built

robust

heavily built

megadontia

massive teeth

sagittal crest

bony ridge running along the top midline of the skull in some mammals, providing a large surface for strong chewing (temporalis) muscles

fallback foods

foods that other animals don’t want; not nutritionally dense

core

heavy butchering and fracturing bones

flakes

use-wear analysis: wood, meat, & grass

edentulous

without teeth