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GWU / Sociology / ANTH 1001 / flared zygomatic arches

flared zygomatic arches

flared zygomatic arches

Description

School: George Washington University
Department: Sociology
Course: Introduction to Biological Anthropology
Professor: W. barr
Term: Fall 2016
Tags: Biological and Anthropology
Cost: 50
Name: Exam 3 Study Guide
Description: Final will be on Wednesday at 12:40PM in the same room that we have class in.
Uploaded: 12/11/2016
20 Pages 7 Views 11 Unlocks
Reviews


Date of Exam: November 9, 2016


when did Paranthropus aethiopicus live?



Exam 3 Study Guide: 

● Exam format will be multiple choice and fill in the blank

● Topics on exam are mostly from lecture and labs, but some from reading ● Chapter 11: Rise of the Genus Homo

○ At around 2.5 million years ago, there is a trend toward global cooling and drying ■ Australopithecus split into two lineages (paranthropus and Homo)

■ Paranthropus have increased size of teeth and cheek size and small body size (robust)

■ Increased brain size and tool-making in homo and decreased

prognathism and teeth size, increased body size

○ Robust Australopithecus: paranthropus

■ CHEWING MACHINE, temporalis and masseter muscle are LARGER than early hominins and later ones

■ Sagittal crest further in front and flared zygomatic arch (dish shape face) ■ Enlarged cheek teeth with thick molar enamel

■ Frontal dental reduction (smaller front teeth) because of crowding and premolar look like molars


when did paranthropus boisei live?



● Bigger teeth than humans even though smaller body size

■ Paranthropus aethiopicus: 2.7-2.8 million years ago, East Africa

● Known from one almost complete skull named “black skull”

● Seems to be middle point between paranthropus and

Australopithecus

● Has prognathism, “dish-shape” face, well developed sagittal and

nuchal crest, relative small brain, forward-projecting cheek bones

(zygomatics)

■ Paranthropus boisei: 2.3-1.2 million years ago, East Africa

● Most forward projecting cheek bones (zygomatics) If you want to learn more check out cell biology final exam

● Less developed sagittal crest but forwardly-placed, less

prognathism

● Teeth have thick enamel, decreased front teeth and large molars

with postcanine megadonty, anterior dental crowding with marked

reduction incisors and canines

■ Paranthropus robustus: 2.0-1.5 million years ago, South Africa


when did paranthropus robustus live?



● Similar to boisei but separated (live in different region)

● Huge chewing apparatus probably to eat tough food, especially in

time of scarcity

a. Being able to eat fallback food during scarcity is very

important to survive

■ “Nut cracking man” crashing/eating nuts which is why they have thick enamel

● Not supported by looking at cuts on teeth of where resources come from (pretty omnivorous probably adapt to eat tough food in time of scarcity)

■ Debate whether paranthropus are own genus or that South African Australopithecus Africanus and Paranthropus robustus are more related than to rest Don't forget about the age old question of com 2080 midterm fsu

● Some evidence for second, most think it is the first theory

○ Emergence of genus Homo:

■ Early evidence of Homo habilis were discovered by the Leakeys in Tanzania, lower jaw and skull with stone tools (found Robust

Australopithecus and Homo habilis but said Homo habilis was the one making the tools because it had a slight larger brain)

■ Early Homo have been found at number sites in East and South Africa ● Ledi Geraru in Ethiopia (half of lower jaw) seen as earliest Homo fossils (2.8 million years ago)

■ Early Homo have larger cranial capacity, slight decrease in teeth size (more parabolic arcade and thin enamel)

● Decreased prognathism and more gracile cranium

● Similar body size to Australopithecus

● Are intermediate between Australopithecus and later Homo

■ ASSOCIATED WITH STONE TOOLS

■ Debate if Homo or Australopithecus because of similar genes, used to be because toolmaking but earlier non-Homo species have been found to use tools

● Most see them as Homo

■ Another debate is how many species? For long time all early Homo were classified as Homo habilis but very different characteristics so may be 2 different species (Homo habilis, Homo rudolfensis)

● Is it sexual dimorphism or 2 different species, probably is that sexual dimorphism would have to be beyond modern day gorillas ■ Homo rudolfensis: 2.4-1.6 million years ago

● Absolutely larger brain size (mean = 775 cc)

● Australopith-like broad midface

● Relatively larger molar teeth

● Well-developed mandible for chewing muscles

■ Homo habilis: 2.4-1.4 million years ago

● Absolutely smaller brain size (mean = 612 cc) Don't forget about the age old question of acmlr

● Broader upper-face than midface We also discuss several other topics like kristian estevez uf

● Smaller molars

● Less robust mandible

● More australopith-like limb proportions

■ BOTH HAVE JUMP IN BRAIN SIZE

■ Oldowan tools industry: 2.6 million years ago-200 thousand years ago (Early Stone Age/Lower Paleolithic)

● Cores: lumps of stone from which pieces are removed

● Flakes: small fragments removed from cores

a. Most useful

● Hammerstones: rounded stone used to remove flakes

● Hard to make functioning tool

● These tools were used to butcher meat (flakes to cut through hide, tendones), cones can be used to cut down tree, Hammerstones to cut open bones to get bone marrow, making dignity and plant

processing

● Earlier evidence of tool use:

a. Swartkrans, South Africa (1.8-1.0 mya)- tools out of bone

and horn cores, getting root fruit and accession termites

(not known if Paranthropus or Homo used them)

b. Bouri, Ethiopia (~ 2.5 mya)- percussions and tool cut

marks on bone NOT TOOLS FOUND, Australopithecus

garhi found here

c. Dikika, Ethiopia (3.39 Mya)- bones with tools cut mark on

them maybe for flesh removal and access bone marrow,

not found with association with Hominins or tools but may

be evidence for using tools for meat consumption before

Homo

d. Difference between carnivore cut marks and tool cut marks

is that tool cut marks are V-shape, carnivore cut marks are Don't forget about the age old question of fau majors

U-shape

e. Lomekwi: tools before Homo (3.3 mya), found in Lomekwi,

Kenya

○ Chimps also use tools

■ Nut cracking, stone tool use

■ Stone transport (<2km)

■ Stone selectivity

■ Small game hunting

○ Unique traits to hominin tool use

■ Large stone transport (>10km)

■ Stone tool manufacture

■ Using tools to make tools (woodworking)

■ Plant processing (USOs)

■ Large game acquisition, carcass processing

■ Pretty clear that early hominin did use tools but maybe have used sticks not stones

○ Hunters or scavengers?

■ Early hominin were butchering large animals but might be scavengers not hunters

■ Probably doing both → opportunistic omnivores (incorporating variety of plant, foods, insects and meat)

○ Homo naledi: age unknown, South Africa

■ Found in Rising Star Cave in Dinaledi Chamber (deep chamber in cave with lots of fossils)

● Many fossils of same species so many individuals

■ Has Homo features:

● Advanced brain case (larger and rounder though not as much as humans)

● Palms, wrists and thumbs are human-like which suggest tool use ● Long legs with human-like feet (suggesting long-distance stride) ■ Has Australopithecus features:

● Shoulders positioned in a way that may help climbing and hanging ● Hips bones flip outward and shorter in front than back than human ones If you want to learn more check out bio 305

● Long curved fingers that might help with climbing

■ AGE IS NOT KNOWN- if very old then maybe existed during Lucy (least probable), more likely to have lived 2 mya or very recent which might mean that Homo was more diverse later on

○ Out of Africa: until now all hominins discussed only seen/found in Africa, now will move out

○ Homo erectus sensu lato: Homo erectus, Homo ergaster (1.8 mya -ca. 30 Ka) ■ Has larger brain and human-like posture (long legs)

■ Homo erectus leave Africa → earlier fossils in Africa then soon in other places including Java

● Able to live in many different enviroment

■ Subject to a lot of variable climate starting 1.8 mya

● Marked by glacial cycles (ice ages → warming → ice age)

● During ice ages you see decrease in sea level so land bridges connect different areas separated by water (reason why seen in Java-able to walk to island)

a. Island population will get cut off

■ Homo erectus cranial looks like football (long braincase), have a mound on top of head (sagittal keel), also have occipital torus (wide back of cranium)

● Average of 980 cc cranial capacity

■ Debate is one or two species, many people divide to Homo ergaster (Africa, ~ 1.9-1.0 mya) and Homo erectus (Asia, 1.8 mya-30 ka) ● Difference based on geography

■ Both are very similar but ergaster have no keel while erectus does

■ Homo erectus last arboreal features so mostly bipedal like humans and could run for long distance (important for hunting)

■ Footprints from 1.5 mya in Ileret, Kenya

● Looking at stride and heel pressure shows that they walked very similar to humans

■ Famous fossil of Homo ergaster is Turkana Boy, has postcranial anatomy ● Adolescent at about 8 years old, about 5’3” showing human-like body size with similar proportions (Africa)

a. Australopithecus was about 3”

○ Acheulean tool industry (1.6 mya - 200,000 years ago)

■ More sophisticated technology, symmetrical biface tools, retouching and soft hammer percussion (bone to be precise)

■ Homo erectus started with Oldowan and later Acheulean, East Asia population that migrated before shift didn’t develop acheulean or couldn’t find tools needed to make them

● Left of Movius (Africa and Europe had acheulean, those on right didn’t

■ Tools have regular proportions, standardized form (shows intention) ● Proportions similar in African, new East and Europe, show more cognitive ability

■ Need mental representation of what you want, needs advanced planning and ability to modify along the way

■ Handaxe were used like swiss army knife (process animal carcasses, wood and other plants, cores to get flakes)- maybe no utilization purposes for shape, only liked- reason why some tools are so big

● Not known why shape or why used for so long

○ Control of fire: start seeing evidence of controlled fire

■ Fire is important for:

● Cooking: make food more digestible so needs less food to get nutrients and neutralize toxins

● Warmth: important for cold places outside of Africa, crucial to move to Asia and Europe

● Cave occupation: allows use of caves as shelter, important for Europe and Asia

● Protection: important for large group, predators don’t like fire ● Hunting: part of complex hunting, used with tools

a. Make animals flee so they can hunt bigger gain

● Social functions: may facilitate formation of social bonds,

emergence of communication

■ Debate over evidence of control fire by humans because hard to tell from wildfire (human-made usually last longer, is more intense and locally- in one point)

■ Evidence of early control fire in Kenya (Koobi Fora in 1.65-1.4 mya) and Chesowanja plus burned bones from Swartkrans (cave) in South Africa 1.5-1.0 mya

● Debate if human made or not

■ Gesher Benot Ya’ Aqov, Israel (790,000 years ago)

● Charcoal

● Burned flints

● Hearths

● Burned grass seeds/grains (maybe cooking)

○ Homo erectus first primate/hominins to migrate out of tropics ■ Variety of environments with seasons and colder regions (Eurasia) ■ Homo erectus migrated out early on

● Dmanisi skulls in Georgia Caucasus in 1.8 mya

a. Debate on what to call it (Homo ergaster, Homo erectus or

Homo georgicus but still in erectus spectrum

b. Small body and brain

c. Many skulls in one area of one group

d. Evidence of old cranial with no teeth that was probably

being taken care of

■ Seen in Java in Mojokerto (1.8) and Sangiran (1.65)

● Questions about provenance and dating (land bridge between Java and mainland Asia) no stone tools found

● Why move out? increased cognitive abilities allowed to colonize new environment

a. Have long-range bipedalism (maybe running)

b. Fire could help

c. Maybe expansion earlier but found recent evidence (not

possible since lacks evidence)

○ Homo floresiensis: 100,000-60,000 years ago and stone artifacts 190,000-50,000 ya

■ Called “hobbit” by media

■ Seen in Flores, Indonesia

■ No land bridge so had to use boat or floating

■ Has Australopith-like brain size (380 cc), but more vertical profile to the face

■ About 3.5 feet tall

■ Australopith-like wrists

■ Short lower limbs

■ Flat feet (no longitudinal arch)

■ Long curved toes

■ Simple flake stone tools (similar to Oldowan) with evidence of butchery, hunting and evidence of fire

■ Why so small?

● Insular dwarfism: reduction in size of large animals when they get

isolated in small habitats (islands)

● In the absence of predators, being small is a selective advantage

because less resources are needed

● Very well known ecological phenomenon observed in many

species: dwarf elephants (Stegodon) also in Flores

■ Where does it fit?

● Microcephalic Homo sapiens? Probably not

● Dwarfed lineage of Homo erectus (dwarfism related to island

habitat)

● Descendant of remnant Homo habilis or Australopith population?

● Chapter 12: Archaic Homo sapiens and Neandertals

○ Pleistocene characterized by lower temperature and more variety of climate ○ Archaic Homo sapiens: 800,000-150,000 years ago

■ Can be put into a big taxonomy called Homo heidelbergensis or splitting taxonomy into 3 species: Homo rhodesiensis, Homo antecessor and 

Homo heidelbergensis 

■ Transitional group of species between Homo sapiens and Homo erectus ■ Population of Homo erectus that stayed in Africa evolved to new species ● Other population in different areas led to different species (Asia → Homo erectus, Europe → neanderthal and Africa → Homo

sapiens), different population with different evolutionary

relationships

a. Homo heidelbergensis led to neanderthals and Homo 

rhodesiensis led to Homo sapiens 

■ When looking at modern human you see large globe cranial shape with big cranial capacity, decreased occipital torus, decrease brow ridge,

hollow above canine called “canine fossa,” small teeth, bony chin and small faces

● Overall all later homo are variations of theme, Neanderthals have

big brain and small face

● Archaic have:

a. Much bigger brain size but similar shape to Homo erectus

b. Double ridge large brow ridge

c. No canine fossa

d. No chin

e. Postcranial is more robust

f. Have higher forehead

g. Decreased molar size

■ COME FROM VARIETY OF AREAS

● Atapuerca, Spain: many different sites corresponding to different

evolutionary periods

a. Sima del elefante (1.3 million years ago) Homo sp.

Species is not known but first humans in Europe, only have

fragment of fossils but known to be homo, oldowan tools

found too

b. Gran Dolina (850-950 thousand years ago) Homo

antecessor, oldowan tools found, better fossils than sima

del elefante, cut marks on bones might hint cannibalism or

rituals (bones being processed like fauna), might be last

common ancestor between Neanderthal and Homo

sapiens

c. Sima de los huesos (400 thousand years ago), 28

individual Homo heidelbergensis, brain capacity of

1100-1400cc, prominent brow ridge, little sagittal keel,

occipital torus, midfacial prognathism like Neanderthals,

LOTS OF DIVERSITY, more complete fossils, clear

relationship with Neanderthals, lots of carnivore and

hominin remains, accumulation of fossils might have been

intentional

■ Other sites in Europe show similarities to Neanderthals

● Homo heidelbergensis direct ancestor of Neanderthals

■ In Africa, you see Homo erectus evolving with no trace similar to Neanderthals, more modern human features (fossil from Jebel Irhoud, Morocco- 160,000 years ago, no midfacial prognathism)

■ Archaic Homo sapiens used similar tools that Homo erectus used early on (oldowan and acheulean)

● See rise of mousterian and levallois technology (tiny flakes taken off to get shape then big flake taken off in shape desired), seen

with hominins and require more planning than acheulean tools

■ Begin to see evidence of big game hunting

● Bones of large animals associated with acheulean tools and

collaborative hunting effort (stampeded animals over edge and

butchered carcass)- more complex social structure

■ Wooden spear found in Shoeningen- Archaic Middle Pleistocene hominins hunted large animals, and possessed specialized toolkits for doing so, more evidence of either cannibalism or rituals in Bodo cranium, Ethiopia (600 Ka)

○ Neanderthals: 150,000-27,000 years ago

■ Seen in Europe and West Asia (~150-40 thousand years ago)- first extinct hominin that was found

● Classical Neanderthals come from europe, seen in Middle East and some in Asia

■ Mean brain size is 1520cc (larger than average human)

● Misunderstood by mainstream culture as brutish but in reality had large brain and complex behaviour

■ Neanderthals have:

● Inflated cheek (midface prognathism), humans have hollow out due to canine fossa

● Occipital bun (mount of bone in back of head), humans don’t have it

● Long jaw with retromolar space (space between last molar and jaw), humans have overcrowding so have no space

● NO CHIN

● Double-arched brow ridges (humans have less brow ridges) ● Large noses (probably to warm up to make it easier to take in oxygen)

● Taurodant tooth

■ Postcranial features included robust, heavily body, larger and barrel-shape rib cage and thick leg bones (probably because of different climates and ecological conditions- Allen’s rule)

■ One behaviour characteristic is evidence of using mouth as “third hand”- lots of anterior tooth wear (similar wear in arctic population of humans) ● Holding hide with hand to stretch and use hands to prepare it ■ See tools called Mousterian and Aurignacian (blade-based technology using wood to get longer blades/flakes)

■ Good evidence of hunting big gain with hafted weapons (stone tied to the end of wooden stick)

● Had abundance of 1 or 2 species (specialization) and healthy adults in prey, evidence of first access cut-mark (no on top of predator marks) and plants

■ NO EVIDENCE OF PERMANENT SHELTERS (using rock shelter) ● Moving around

■ Some evidence of burying the dead but no religious nature behind it ● Seen in site in Shanidar called “the flower burial”- fossil with pollen and in intentional position

a. Debated that maybe the pollen from rodent burrows

■ Lots of evidence that shows they had difficult lives- didn’t live long (not beyond 40) and older ones suffered disabling diseases or injury (older man in La-Chapelle-aux-saint have lost teeth to gum disease and in Shanidar had blow to head which could have disabled him but lived long enough to heal)

● Maybe a result of hunting large mammals

■ Potential jewelry made up eagle talon that have signs of being made into a necklace (Croatia, about 130,000 years ago)

■ Modern behaviour include burials, personal ornaments, care of elders and rock art

● Not as good at art as humans

○ Neanderthals-modern human interactions:

■ Both species co-inhabited in Europe for about 10,000 years (40,000 to 30,000 years ago)

■ Hybridization has been proved through DNA testing

● 1-4% Neanderthal DNA in Europe and Asia

● Especially people of Europe have DNA from Neanderthal- keratin, skin color, risk to certain disease, cell surface immune receptors

while other areas lack Neanderthal DNA (activated testes, located

in the y chromosome)

■ Did they exchange knowledge?

● Late association of Neanderthals with Chatelperronian tools

(similar to those associated with humans)

■ Did the interactions lead to their extinction?

● Maybe Neanderthals extinct due to direct competition and

ecological competition with humans or there was a genetic

replacement

● Chapter 13: Emergence and Dispersal of Homo sapiens

○ Anatomical feature to distinguish modern humans:

■ Large cranial capacity (mean = 1350cc) with basketball shape head with high forehead

■ Less brow ridge, limited development of occipital torus

■ Prominent mastoid process

■ CHIN (small face with little prognathism)

■ Canine fosa (hole on top of canine), small teeth and jaw

○ Earliest modern human were found in Africa- Omo, Ethiopia (195 thousand years ago)- first ANATOMICALLY modern human

■ 2nd found in Herto, Ethiopia (165 thousand years ago)

■ Still had some different (smaller brains) but super similar- much later appeared of behaviours in humans

○ Klasies River Mouth, South Africa (120-90 thousand years ago)- extremely similar to modern humans

■ Start seeing modern humans outside of Africa later on- skulls and Qafzeh, Israel (110 - 90,000 years old)

● Moving out from Africa

○ NOT A LOT OF EVIDENCE THAT BEHAVING LIKE MODERN

■ Had similar tools than Neanderthals (middle stone age tools)

○ After 90,000 years ago, Neanderthals enter Middle East again because cold weather- modern humans disappear and are replaced by them

■ Switch again later on with Neanderthal population decreases and human population increase

○ Earliest anatomically modern human using mousterian tool and levallois technique

■ Later come aurignacian which is using other things (wood) to cut out precies blades (variety of tools made of stone, bone or antler)

● Blade-based technology

○ Behavior modernity not seen at once but gradually acquisition (through time) ■ No single cognitive explosion

○ By 60,000 years ago in Africa we see:

■ Projectile technology (throwing spears or bow/arrow)

● More likely to be successful so increase survival for those using so competitive advantage

■ Fishing (bone tools that help with fishing in Katanda, DR Congo (82-70 thousand years ago)

● Probably fishing 2 species of catfish (large species)

● Helped get new resources

■ Personal adornment (probably because of larger social networks, exchange networks)- beads made of shellfish, with holes with worn on one side and mineral pigment

● Personal adornment can show group membership

■ Belief systems (graves with artifacts, body adornments or red ochre) ● Might show ritual or belief of afterlife

○ Art began to be seen after 40 thousand years ago in Europe and Africa with evidence for music, rock art, portable art including figures

■ Music: predates evidence of care art, flutes made from animal bones ● Might show social and emotional information

● Debate if Neanderthals had music but MODERN HUMANS DID ■ Rock art: best examples in caves in Europe (Germany and Spain) ● Debate over what its purpose was (teaching? planning?)

● Using different natural substances and different instruments

● Variety of scenes, usually animals (human figure are rare) and some abstract patterns

● Som scenes have no animals only nature and others include animals not hunted

■ Portable art: delicately carved ivory horse head, venus figures (Gravettian from 25,000 years ago)- maybe showing fertility

○ Expanded subsistence base:

■ More variety in diets (including aquatic resources)

■ Sites occupied for longer periods and extensively modified (evidence for permanent shelters)

○ Modern human advantage: not seen in previous hominins

■ Innovative: new, more elaborate technology (projectile weapons, clothing, shelter and other material culture)

■ Cognitive: personal adornment, symbolic behavior, art, music and ritual ■ Social: larger social networks, exchange networks, buffered risk of starvation

○ Modern humans first moved within Africa, then Middle East, Europe, Asia, Australia, the Americas and finally islands

■ Took a while to get to Europe because Neanderthals

○ Multiregional model: no debate over first Homo erectus out of Africa event but say that separate groups evolve on and interbreeding between region lead to one Homo sapiens across globe (evidence that Homo erectus in each region look like modern humans)- NO LONGER BELIEVED AS MUCH

○ Out of Africa model: still say that first out of Africa event happened with Homo erectus but modern humans originated in Africa and dispersed to occupy world and replace existing hominins (evidence is fact that modern humans have little genetic variation)

■ Little or no interbreeding

○ Assimilation model: agree that Homo erectus out of Africa, had regional populations and modern human in Africa and moving out BUT INTERBREEDING WITH HOMININS OCCURRED (best supported by genetic evidence focused on mitochondrial DNA- material inheritance with rapid mutation and molecular clock (show when mutation occurred)

■ More diversity in Africa showing that humans have been evolving there for longer time, if multiregional was true then diversity will be same around the globe

■ African origin has been supported by mitochondrial DNA, Y chromosomes and nuclear DNA markers

■ Looking at Neanderthal DNA shows evidence of interbreeding

● Chapter 14: Evolution of the Brain, and Behavior and the Human Life Cycle ○ “Ape mind”:

■ Chimp have social learning and “traditions”

■ Tool use (great apes and some monkeys)

● Not as complex as tools used by early hominins

■ Apes have self-awareness and self-regulations (know mirrors is them) ● Show apes might have state of mind- see selves as individuals

■ Social tolerance (help transmit knowledge)

○ BRAIN DON’T FOSSILIZE (fatty, gel-like tissue than undergoes decomposition)- usually left with brain case that can fill with sediments making endocranial cast that show brain size and shape

■ Rare but have good example in fossil record

○ Can compare to other primates using macro and microscopic companion ○ Humans brain are exceptionally big (implication that larger brains can be more cognitive complexity than smaller ones)

■ As animals get bigger their brains get bigger at slower rate (humans has biggest brain than expected based on body size)- ENCEPHALIZATION: proportional size of brain relatively to body size (show that more energy given to brain)

● Human is most encephalized animal, dolphin is second

● Human brain is larger than other primates based on body size ○ Through human evolution there has been trend of strong increase of brain size (more profound starting with Homo erectus)

■ Neanderthals have similar brain size than us and some have bigger ones (though this doesn’t mean more encephalized because have larger body size)

■ Trend shows that natural selection is driving bigger brain size so important

■ More to it than brain size but easier to see in fossil

○ Brain anatomy:

■ Brain divided into left/right hemisphere

■ Brain stem: base of brain, “reptile brain,” regulating basic body functions ■ Cerebellum: also at base, integrates sensory perception, coordination and motor control, learning motor skills

■ Cerebrum (neocortex): outer part of brain, higher cognitive functions such as sensory perception, generation of motor/action commands, spatial reasoning, memory, conscious thought, speech, language

● Gyrification index: degree of folding of cortex, human are highly gyrified (ration of total cortical surface to outer cortical surface),

increase with brain size to allow more neocortex to fit within skull) a. Can’t keep adding to size of brain because harder to give

birth

b. Increase brain capacity with less brain size increase

■ Parietal lobe: integration of sensory information from different modalities, important for tool using

■ Occipital lobe: primary visual cortex (back part of brain)

■ Temporal lobe: primary auditory cortex, visual object recognition, processing of semantics, long-term memory (ear)

■ Frontal lobe: many functions associated with higher cognitive associated with intelligence (front)

○ When looking at areas of human brain that look at basic functions (primary areas) with other animals you see, lots of areas of human brain is NOT associated to primary functions

■ Lots of association cortex- not primary function but processing and INTEGRATING information

■ Somewhat in human evolution saw an increase of association cortex ○ Brain reorganization:

■ Olfactory regions are smaller with large visual cortex (seen in primates) ■ Have more cerebral cortex than expected (increase of cerebral cortex is not uniform-prefrontal, parietal and temporal have seen an increase)

■ Prefrontal cortex: involved in decision-making, planning, working, memory and emotion-regulation

● Have more complex neurons

● Expanded in apes in comparison with other primates. Humans show a further expansion of this area compared to apes.

■ Human have smaller primary visual cortex than chimps because increased parietal to integrate sensory

● Seen of endocranial cast in Taung Child- debate if back of head structure show smaller primary visual cortex (human-like) but

others say that they had large primary visual cortex (chimp-like)

a. Debate can be because don’t have brain to see structure

b. Have to depend on other evidence because tools to see

cognitive ability

○ Human language: complex symbolic language seen in all cultures ■ Voluntary and SOCIALLY LEARNED (still have involuntary use of auditory instruments- life screaming)

■ Semantic: use arbitrary symbol to convey meaning (phone mic) ■ Syntax: ORDER MATTERS (dog bites man vs man bites dog) ■ Recursive: phrases within phrases (hierarchical structure)

● Can order recursive order to produce infinite number of sentences to build image of something

■ Displacement: speak of things not physically present

○ Language-like abilities of other primates:

■ Can produce communication voluntarily, can be learned and is symbolic ● Predator call with specific it in ground or air

■ Limited master of syntax and ability to speak of something not there ○ Language areas on human brain:

■ In left hemisphere (Broca’s area-speech production, Wernicke’s area important for speech comprehension)

● 95% of humans have most of long areas in left sick of brain (most for right-handed people)

● Brain adaptations before vocal adaptations- maybe non-spoken language

● Know of them through accidents and MRI

■ Broca’s area in primate seem to NOT be connected to vocal audio ○ When did it evolve? Asymmetry of Broca’s in Homo erectus but hard to know what it means

■ Looking at vocal track you see larynx (vocal box) in lower position so bigger and shape different so make more sound than chimps and humans have smaller tongue with different shapes (flexion of cranial base might show this)

● Infants can’t make sound because larynx hasn’t stopped

● Neanderthals might not have speech ability

○ FOXP2: regulatory gene involved in speech and language

■ Seen in all vertebrates different in human in 2 amino acid

■ Natural selection for it

■ Neanderthals have this so either appears before divergence of the species or entered through interbreeding

○ Large brain consumes sixteen times more energy per unit mass than muscle to obvious selective advantage if willing to reduce this

○ Compared to other mammals of similar size, primates develop slowly and invest heavily in offspring

○ Primates have:

■ Long gestation lengths

■ Large neonates

■ Low reproductive rates (i.e., they reproduce infrequently)

■ Long developmental periods & late ages at maturity

■ Long lifespans

■ Large brains

○ Primate life stages:

1. Prenatal period: conception to Birth and susceptibility to teratogens 2. Infancy: begins at birth, depends on mother for nutrition and protection (lactation), ends with weaning and eruption of first permanent tooth 3. Juvenile: travel and forage independently, learn important social skills, ends with sexual maturation

4. Adulthood: reproductively mature, begins at eruption of last permanent tooth

○ Distinctions features of human cycle:

■ Childhood: between infancy and juvenile, occurs after weaning, when children are still dependent on others for food , period of learning technical and social skills, language, ends with the attainment of adult brain size

● No longer physically weaning but depends on parents

■ Adolescence: between juvenile and adulthood, begins with the onset of sexual maturity, allows for an extended period of social learning, and continued brain maturation, marked acceleration of body growth, ends with attainment of adult height

○ Additional derived features:

■ Long post-reproductive lifespan

■ Humans have relatively large neonates: usually neonates get larger as species get larger, newborn humans weight about 6% of mother weight ■ Long gestation length

■ Human neonates have large percentage of body fat (quarter of body weight is fat at around 6 months)- probably related to growing brain (support energetic costs and provide important substrates for brain development)

● Also buffer against the cost of nutrition disruption and infection following weaning

● Humans wean infants earlier

■ Humans still dependent even after weaning

● In other primates once mom stops nursing job is over but not true for humans

■ Humans have absolutely and relatively large brain

■ Human brains are UNDER-DEVELOPED at birth

● At birth humans have about 27% of brain size, chimps have 36% ● Humans grow large proportion of adult brain in postnatal life (especially fast in first 18 months)- why?

1. Obstetrical constraint: tight space for big brain to fit leading to death, space is small because bipedalism requires a

pelvis with narrow birth canal

2. Metabolic constraint of gestation: requirements of nutrition out pace maternal supply at around 9 months (limit

reached)

3. Selective advantages of extended neural development: key maturation changes in brain continue through

adolescence, neural circuits responsible for behavior are

shaped by experiences in local environment

■ Prolonged period of SLOW body growth during childhood then has marked adolescent growth spurt (late in onset and high magnitude) due to lots of energy used in brain development in childhood so don’t have enough for body growth

a. Grow a lot as infant then steady until huge growth in puberty b. Trade of between brain and body growth, once brain done focus on body

■ Human menopause: post-reproductive period in female life where permanent cessation of ovulation and menstruation occurs ● Midway through lifestyle- before advanced somatic aging (might be because have slow somatic aging compared to fast sexual aging)

● Fertility doctrine has been seen in other female primate but not complete

■ Humans have reduced age-specific mortality (long lifespan) ● Chimps have shorter life-even in zoo

● Humans have LONG LIFE

● Might be due to menopause of female that lead to grandmothering hypothesis: non-reproductive females help care of grandkids (will help ensure that genes grandmother share with kids will be carried on)

● Males don’t get menopause, they see decrease of sperm quality ■ Early weaning- provisioning (nutritional supplementation in childhood) ■ Short inter-birth intervals- human mothers may support multiple dependent offspring at once (can have more than one dependent

offspring) but question becomes how to provide care for infant while

taking care of other offspring- extensive paternal care and cooperative breeding (strategy where non-parental members of group help support offspring)

● Parent must produce enough food to feed kids might led to tool

development, slow during childhood, and non-parental adults

helping

○ Origins of modern human life history:

1. Comparative humans and other animals

2. Look at fossil record (body size, brain size and dental development) a. Dental development: teeth are abundant in fossil record, tooth

molar eruption shows age/development (first molar eruption of

chimps at 3 while human at 6)

b. Can see daily life in teeth provide a method of estimating death,

weaning and other

c. Taung child: based on dental can see at about 3.73-3.9 years at

death (more like chimp-like)

d. Homo erectus: see first evidence of shift of pace of development

(not modern but closer)

e. Neanderthals time slightly faster foot growth

● Chapter 15: Biomedical and Forensic Anthropology

○ Forensic anthropology is applied biological anthropology in medico-legal context ■ Applied scientist take scientific knowledge and applies it to something else

■ Forensic anthropologists apply knowledge of osteology and human variation to legal context

■ They collaborate with others (medical examiner, pathologists)- people that investigate deaths and causes behind them

○ Usually forensic anthropologists are called in when there is a manipulation to a body up to only bones being present so they can use knowledge to help with investigation

○ Main jobs of forensic anthropologists:

■ Help to make positive identification (main goal)

■ Help determine cause of death

● Forensic genetics can be very useful for IDs, but often there are

no samples to compare with to unknown victims (when there is

nothing to compare to then it won’t help)

● Useful in very old cases where there will be no soft tissue (harder

to get DNA from bones)- Forensic anthropology may be critical in

these cases

■ Main way they help is to create biological profile from skeleton

● Age at death- help narrow it down

● Sex- help eliminate 50% of possibilities of who victim is

● Ancestry- tad tricky because there is a lot of overlap between groups of different ancestry, but can be figure what they are not ● Height and weight (especially if you have full skeleton)

● Premortem injury and disease- stuff that occurred before death might help see who person

● Perimortem and postmortem trauma (stuff that occurred around death)

● Time since death

○ Age at death:

■ Dental eruption sequence offers clues for younger individuals ● For people under 21 to get rough estimate of their age using what teeth they have and which they don’t

● Only work before you get 3rd molar

■ Epiphyses: pattern of fusion of bones

● Multiple bones have centers of growth plates- different parts of bone separated by a epiphyseal line and when growth is done

then there won’t be a epiphyseal line

● If you can see the regions of body that are fully fused or not, you can guess proximal age because patterns of closure are

predictable over course of skeletal maturity within rage of ages

(19-30 years)

■ Pubic Symphysis: area where two sides of pelvis come together ● When you first reach adulthood, your pubic symphysis has

discrete pattern with strong ridges and over time the ridges get

eroded and the overall shape changes

● There are stages that can be put with certain ages

■ Cranial Suture Obliteration:

● Cranial bones will begin to fuse together as you get older, suture lines between the different bones will become less visible as you go on (older individuals will seem to have only one bone)

■ NEED TO PUT ALL TECHNIQUES TOGETHER TO GET AGE (one alone is not enough)

○ Sex:

■ In other species you can look at sexual dimorphism in size to see difference between male and female, harder to do with humans because there is a lot of overlap in size between the two

■ Features of pelvis and skull best things to look at to get diagnostic (in adults only- not so much in juvenile because changes not noticeable until puberty is over)

■ In skull, males tend to have a more rugged brow ridges and chin while females have less brownridge, more vertical forehead and mastoid process being smaller

● Differences are very small compared to other primates

■ Pelvis is most reliable way to see sex because female pelvis are made to be able to give birth so it is shaped differently- have elongated pubic region and wide subpubic angle to make bigger birth canal

● Truth even if female has not given birth

○ Height and weight:

■ Height is easy to tell if you have a more or less a complete skeleton, if you have less bones you can calculate a proximate height

■ Weight is more tricky because it fluctuates during lifespan, but it is related to joint size (weight bearing) because they need to be able to withstand weight and width of pelvis because broader people will have broader pelvis

○ Pre-mortem injury and disease:

■ Healed fractures can offer clues as to life-experience and identity especially if the injury/disease is extreme and rare

■ Can tell if injury is occurred before time of death because it might be healed which takes time (if during death then there would be no healing) ■ We all have specific record of dental procedures in teeth which can aid in positive identification- if you have possible victim that has or doesn’t have specific procedures then you can tell if it is them or not

○ Perimortem trauma: trauma that occurred around time of death ■ No evidence of healing after injury occurred which can offer clues to cause of death

● Examples include breaking hiway bone when strangled, gunshot wounds in skull (two holes on either side with fractures that spiral out from point of impact), blunt objects causing breakage of skull that is bigger than gunshot, long chip on skull can be injury using sharp instrument, sharp-force trauma between rib bones might

mean stabbing

■ Won’t always be cause of death, but might be (build up list of possibilities) ○ Ancestry: what is racial or ethnic background of an individual ■ Tricky to determine because traits of race are very heterogenous and overlap with characteristics of other groups, but there are some aspects that are more common in some populations than others

■ There are large databases that list data on skulls and skeletons of known ancestry that can be compared to unknown skeleton

■ Won’t give exact answer but will help rule out possible choices ○ Times since death:

■ Phases of decomposition is studied- example is pig dressed in clothing and studied during decomposition until only skeleton remains

■ Can look at predictable patterns of decomposition and patterns of insect/arthropod presence

■ There are various of body farms where people donated bodies so decomposition can be studied (look at rates and search for possible clues)

○ Other applications of forensic anthropology:

■ Mass fatalities: in 2005, about 42% of 9/11 victims were still unidentified so massive number of forensic anthropologists and geneticists have helped identify victims

● Hard to identify because big events will lead to destruction of body ■ War dead: defense department has POW/MIA Accounting Agency- task force that is tasked to identify all POW and MIA soldiers from wars ● They are sent all around the world to help recover and identify soldiers

■ War crimes and genocide: have played important role in Rwanda, Bosnia, Cambodia and other places where war crimes have occurred to identify the victims

● Working for government or NGO groups

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