exam 2 (copy)

adaptation

evolved phenotypic traits that increase an organism’s reproductive success

adaptationism

every aspect of an organism is the product of natural or sexual selection

great rift valley

east africa, creation and disappearances of lakes and streams during hominin evolution, series of volcanoes in this valley

holism

many apparent adaptations may be a by-product of the natural selection process

hominin

all species on “our” side of the imaginary line between apes and humans, all fossils since the last common ancestor with chimps

oldowan tools

earliest stone tools, cores/flakes, hammerstones, carried around

orrorin tugenensis

“millenium man”, found in 2000 in Kenya, dates to 6 million years ago, possibly bipedalism, thick enamel, small teeth, larger upper canines

pelvis

bowl-shaped for easier biped balance

reductionism

focuses on each component to understand the whole, each part of the organism is adaptive

robusticity

the amount of structural material (bone tissue) for a given structure relative to the overall size (mass or length) of the organism

tool industry

particular style or tradition of making tools

valgus angle

angled femurs, problems at the knee

what are the anatomical changes related to the shift to bipedalism in humans?

partly in response to climate change, followed by increase in brain size, changes in pelvis, vertebral column, dentition

what are the five hypotheses that have been put forward for the development of bipedalism? what are there five and not just one accepted hypothesis?

savannah/aridity, turnover pulse, forrest, variability selection, pulsed variability selection

what are the earliest known tools? which species seems to be associated with them?

oldowan industry tools associated with homo habilis

au. aethiopicus

dates to around 2.7-2.5 million years ago, good candidate of later robust species, no known postcranial remains

au. afarensis

dates to around 3.9-2.9 million years ago, lucy (most famous fossil of this group), fully bipedal, small brain, polygynyandry

au. africanus

dates to around 3.5-2.0 million years ago, taung child (most famous fossil of this group), slight brain increase, bipedal anatomy, south africa

au. boisei

dates to around 2.3-2.1 million years ago, tanzania, brain size around the same as the robusts from south africa

au. garhi

dates to around 2.5 million years ago, “the unexpected southern ape”, small face, more human-like postcranial proportions, possible stone tool use

au. robustus

dates to around 2.0-1.5 million years ago, south africa, biped and hominin, diet probably included animal protein

cohabitation

two or three hominin species in the same regions in the african continent, natural selection molded them to avoid feeding competition

lucy

found by donald johansen, clear human-like and ape-like features, type specimen for this species is more complete skeleton than nearly any other fossil human, au. afarensis

paranthropus

“robust australopithecus”, chewing muscles that include high bite forces, living in woodland and open woodland habitat, appears to have been an evolutionary dead end

prognathism

an extension or protrusion of the lower jaw (mandible)

sagittal crest

prominent ridge of bone that projects upwards from the cranial vault along its midline

taung child

slight brain increase, rounded vault, no crests, less projecting face, bipedal anatomy, endocast of braincase, au. africanus

why is it that dates for south african hominins are often less reliable and harder to discern than for those is east africa?

east african sites have volcanic ash, which aids in chronometric dating

what are the main differences between the possible ancestor-descendant relationships within australopithecines? could the currently identified australopithecines be the ancestors of modern homo?

many scientists derive au. afarensis from au, anamernsis and see au, afarensis as the base of au, africanus, au, gahri, and au, aethiopicus, robust australopithecines are too specialized to be ancestral to homo

what are the general anatomical features that differentiate australopithecines from homo?

homo had smaller molar teeth, jaws, and faces and bigger brains compared to australopithecines

acheluean

h. erectus tool technology, dates to around 1.76 million years ago - 250,000 years ago

butchering sites

contain bones with cut marks

cortex

the outer layer of rock formed on the exterior of raw materials by chemical and mechanical weathering processes

denisovans

siberia, split from common ancestor to neandertals, not yet classified as own species separate from human, include genetic markers that have been associated with modern human high altitude populations

globular

globe-shaped/spherical

h. erectus

adaptive shift around 1.8 million years ago, body and brain size increase, similar shape/size to h. sapiens, oldowan and acheulean tools, left african and migrated

h. ergaster

found in africa and europe, thinner cranial bones and less pronounced brow ridges

h. floresiensis

dates to around 100,000-50,000 years ago, “the hobbit”, found in indonesia, small body and brain, large teeth and large feet, used stone tools

h. habilis

dates to around 1.9-1.4 million years ago, tanzania, “the skilled human or handyman”, less apelike face and skull, smaller jaws with humanlike teeth

h. naledi

dates to around 335,000-226,000 years ago, south africa, means “star” in sotho language, small brain size, hands and teeth are humanlike, “long-legged”

h. neanderthalensis

dates to around 400,000-40,000 years ago, europe and asia, closest extinct human relative, bigger brains

h. rhodesiensis

dates to around 600,000 years ago, ethiopia and tanzania, large cranial capacity

h. rudolfensis

dates to around 2.1 million years ago, species included both large and small individuals at first thought to be h. habillis

h. sapiens

dates to around 300,000 years ago to present, “anatomically modern human”, evolved in africa, large brains, smaller teeth

haft

an artifact, often bone, stone, or metal, that is attached to a wooden handle

home base

central place where hominins would have slept and ate

island dwarfism

a process where only smaller animals trapped on the island survive, as food declines to a borderline level

k-selected

maturity reached at 15, higher diet quality

levallois technique

middle palaeolithic (middle stone age) stone-flaking

lumpers

all larger brained hominids are part of a single evolving species (h. sapiens), archaic h. sapiens are likely ancestral to later hominins in each region

mousterian tools

associated with neanderthals in eruope, western asia, and northern africa, flaking technique, small axe

movius line

theoretical line that separates parts of europe, africa, and asia with or without acheulean tools

quarrying sites

contain raw materials for tools

splitters

neadnertals as h. neanderthalensis and denisovans as h. denisovensis, h. heidelbergensis as common ancestor for both neandertals and modern h. sapiens, no interbreeding between species

wallace line

imaginary divider used to mark the difference between species found in australia and papue new guinea and southeast asia

what are the defining characteristics of the genus homo? what are some of the gradual changes we see as we go from early homo to archaic homo?

genus homo have large cranial capacities, bipedalism, opposable thumbs, the ability to make standardized tools

what are the differences between confrontational scavenging and passive scavenging? what are some of the arguments made as to why early homo may have performed one or the other or hunting rather than scavenging?

confrontational scavenging is fighting off predatory animals to gain access to meat and marrow, passive scavenging is taken from carcasses after another animal has killed and gotten the good part

which is the first species in the genus homo that leaves africa? how far does this species go around the world?

h. ergaster, expanded to souther eurasia

what behavioral modification is often found in neanderthal fossil remains? what cultural practice has been hypothesized for other hominins but is clearly expressed in neanderthals?

neanderthals developed faster, possibly had a fairly sophisticated form of language

how are denisovans related to homo sapiens? to neanderthals? how were denisovans indentified?

evidence suggests the denisovans and neanderthals all share a common ancestor with h. heidelbergensis

assimilation model

compromise between other models, modern h. sapiens developed in africa, interbred with archaic h. sapiens, africa has older fossils, traces of archaic dna in modern humans

aurignacian tool industry

careful selection of fine-grained rock such as chert, flint, or obsidian for blade cores, the production oof relatively standardized, parallel-sided artifact blanks from these cores that could be used to make more specialized cutting, piercing, and scraping tools

axon

where electrical impulses from the neuron travel away to be received by other neurons

bering land bridge

closed most recently between 24,000-15,000 years ago, ice free corridor but still difficult to pass

broca’s area

speech production

clovis culture

11,000-13,000 years ago, based on expert stone flaking technology that produced fine, fluted points, seen in new mexico and in north and central america

coxcatlan cave

dates to around 29,000 years ago, central mexico, domestication of important plants (maize, squash, beans)

dendrite

receive input from many other neurons and carry those signals to the cell body

encephalization quotients (eq)

ration of actual brain size to body size

evolution of behavior

paleontological reconstruction of behavior, biocultural approaches, human evolutionary ecology

evolutionary psychology

approach to understanding the evolution of human behavior, emphasizes that natural selection of specific behavioral patterns, behavior as biologically determined through natural selection

fission-fusion strategies

groups will split up (fission) during the day and come back together (fusion) at the end of the day

human evolutionary ecology

ecological factors that influence reproductive success in living hunter-gatherers

irhoud 10 fossil

dates to around 315,000 years ago, morocco, earliest evidence of derived facial features, 100,000 years before earliest evidence of modern h. sapiens

language lateralization

995% of the population has language centers on the left hemisphere, likely that right-handedness and language ability evolved together

microliths

small, shaped flakes probably attached to wood or bone

monte verde

dates to around 15,000 years ago, chile, earliest known americans were established there during the ice age

multiregional model

origins cannot be pinned to a single population or area, gene flow between all regions maintained similarities through development, does not uphold separate and multiple origins of modern humans

myelin

insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord, white matter

neurons

information messengers, gray matter

olfactory bulbs

basic trend in bulb reduction in all living anthropoids, other sensory domains and cognition increase

paleontological reconstructions

reconstruction of behavior of hominins synthesized from both paleontological and contemporary data

replacement model

localized african origin, sapiens fossil in africa first, did not interbreed (much) with indigenous hominins, two species co-existing in each region

subsistence

strategy for food acquisition, highly dependent on richness of the environment, may have been beneficial to expand even further

wernicke’s area

speech comprehension

white sands footprints

dates to around 23,000 years ago, new mexico, fossilized footprints show early humans and ice age animals coexisting

what are the defining features of anatomically modern humans (amh)?

increase in brain size, less robust, more gracile, defined chin, thicker bones

why is the encephalization quotient so important when exploring cranial capacity and intelligence?

this practice has led to the discovery that human ancestors were more intelligent and advanced than what was once believed

what are the four characteristics of language in humans? how does this differ from communication between non-human mammals?

adaptation, semantic, phonemic, and grammatical, language is believed to be a replacement of grooming, evidence suggests that early human ancestors did not posses bones in throat for humanlike speech but still communicated in different ways

what recent finding suggest that cave art took a lot more effort than previously thought (think pigment)?

cave art is the lascaux cave shows that the artists travelled a long distance to get a certain type of pigment, the cave art also shows that the artists would have had to create a ladder and a light source to be able to create art

what mode of subsistence has been the most prominent throughout human existence?

foraging (hunting and gathering)

what is some of the best evidence of the first presence of humans in the americas? what is some of the less reliable but still possible evidence?

the bering land bridge suggests that early humans walked across continents and settled in the americas

azilian

dates to around 12,500-10,000 years ago, iberian peninsula, microlith, small game and fish, megafauna almost gone

tardenosian

dates to around 10,000-8,000 years ago, iberian peninsula, increase in complexity of stone points, extended into northern italy and eastern europe

backed blades

prehistoric flint knife having one edge blunted

burin

engraving tool with a metal shaft that is cut or ground diagonally downward to form a diamond-shaped point at the tip

celts

early indo-european people who spread over much of europe, stone carving and fine metalworking

ceramic mesolithic

some groups begin the use of pottery well before the expected sedentism of the neolithic, earliest dates to 20,000 years ago from china

corded ware pottery

practiced by jōmon and jeulmon, pottery decorated with cords, very precise and time consuming

doggerland

landmass connecting great britain to mainland europe, drowned by the southern north sea following the last ice age