human origins exam 3 units 1 and 2

anthropology (definition w the 4 fields)

the study of people (biological/physical, archaeology, cultural, and linguistic)

biological/physical anthropology

study of human biology (bones)

archaeology

study of objects to tell us about people

cultural anthropology

study of living creatures and societies on their beliefs, practice, and language

linguistic anthropology

study of language and communication

natural selection developed by Charles Darwin

reproduction of individuals with favorable traits that survive environmental change bc of those traits

artificial selection

process for when humans intentionally breed plants or animals to produce desired traits

genetic drift

random changes in allele frequencies from one generation to next

sexual selection

selective pressure specifically affects reproductive success rather than survival

ex.facial hair in men, wider hips in women

species

unit to classify living organisms

-ability to interbreed, produce offspring, common characteristics, can reproductively isolate from other groups

ex. Homo sapiens (all human belong here)

microevolution

adaptation of a species over time to environmental changes

macroevolution

emergence of new species, extinction of species, divergence of evolutionary changes

primitive traits

emergence of new species, extinction of species, divergence of evolutionary changes

derived traits

traits that have been more recently changed

laetoli footprints

famous set of fossilized footprints found by Mary Leakey

were most likely australopithecus afarensis

showed the idea of bipedalism evolving

hominid

any member of the great ape lineage (chimps, gorillas, orangutans)

hominin

any member of the human lineage

facultative bipedalism

animals that can walk on two legs when needed, but will normally move on all fours

obligatory bipedalism

animals whose primary and natural way of moving is on two legs

“Man the hunter”

emphasizes that hunting was key to our human evolution (human anatomy, social organization, cognition, and culture)

what are the critiques of man the hunter?

chimps hunting and cultural survival

Free hands for tools hypothesis (Charles Darwin)

walking on two legs allowed our ancestors to use hands for carrying, making, using tool, gather food, and carry offspring

what are the critiques of the free hands for tools hypothesis

we became bipedal before our brains grew

we can sit to use tools

Vigilance hypothesis (Raymond Dart)

standing upright allowed for ancestors to see over tall grass, see predators, and detect food/resources in the distance

what are the critiques of the vigilance hypothesis?

made them vulnerable to predators

happens for a short period of time

Locomotion efficiency hypothesis (Richard Taylor)

walking on two legs is more energy-efficient than moving on four limbs

thermoregulation hypothesis (Peter Wheeler)

ancestors could stay cooler in hot environments when upright walking

less direct sun exposure

more cooling air from air flow

what are the critiques of the thermoregulation hypothesis?

the sun will not be directly over head all the time

Male provisioning hypothesis (Owen Lovejoy)

walking on two legs allowed for human males to carry food back to females and offspring

what are the critiques of the male provisioning hypothesis?

do not need to be bipedal to carry food back

assuming the early human structures

Aquatic ape hypothesis (Elaine Morgan)

at some point, humans evolved partly in aquatic environments

what are the critiques of the aquatic ape hypothesis?

very speculative and does not have strong evidence

threat display hypothesis (Nina Jablonski)

standing upright made human ancestors look bigger, more intimidating, and more dominant, meaning they scared predators off

postural feeding hypothesis (Kevin Hunt)

bipedalism started from standing upright while feeding in tress and it evolved to regular walking

threat of predation against hominins, role in shaping human evolution, specific predators that hominins faced

discovering the biological/cultural effects

predators include: leopards/big cats, birds

what are the strategies against predation by hominins?

living in groups (mobbing), hominins getting larger, language for warning others

Oldowan (Mode 1)

oldest stone tool industry

known for flake and chopper tool

Chopper

stone cobbles with a few flakes struck off them

flake

parts of the chopper that are coming off when the hammer stone hits the chopper

Hammerstone

the rock that is hitting the the chopper to create the flakes

bulb of percussion

the rounded swelling on the flake stone that is created when force is applied from the hammer stone

knapping

process of shaping stone into tools by striking/pressing flakes off a larger rock

Acheulean (mode 2)

carefully shaped both sides of the tool

Acheulean biface cleaver

two-sided stone tool with a broad cutting edge

Acheulean biface handaxes

handheld cutting tool, shaped like a tear drop

showed an increased intelligence and craftsmanship

what do biface handaxes tell us about cognition?

showed a major increase in intelligence and craftsmanship

fine motor skills

understanding the cause of creating these tools

Dmanisi skulls

Found in Georgia and when they were found it was said that all of the skulls were different indicating this variation (signaling intra-species)

intra-species diversity

variation within the species

inter-species diversity

variation between species

cooking hypothesis

cooking food allowed for easier chewing and digestion, allowing extra calories available to fuel energy hungry brains

bottom-up morality

morality could develop through evolution

ratchet effect

presents the idea of cumulative culture

cumulative culture

process by which cultural knowledge, skills, and tech build up over generations (humans have this and chimps dont)