Intro to Anthropology Lectures 9-10

Neanderthals (H. neanderthalensis)

• discovered 1856 in Neander Valley, Germany

• first non H. sapiens hominin to have DNA sequenced

• EUROPE, MIDDLE EAST, Central Asia

• 200-40Ka

• lots of fossils (& subfossils)

• NOT our ancestors

• large cranial capacity (1400 cm³)

• long, low, flat cranial vaults

• NO FOREHEAD OR CHIN

• robust faces & skeleton (prominent brow ridge)

• slightly shorter avg. height than H. sapiens

Neanderthal Culture

• Mousterian industry (tool making) (flaking techniques/improved Levallois technique, “hand axes”)

• diversity of styles and materials of tools

• open site, caves, and rock shelters

• lacked long distance projectiles (BUT hunted some large game) (meat eating)

• probably capable of symbolic speech

• DELIBERATELY BURIED DEAD

• possibly wore clothes

Ancient DNA Difficulties

• available technology

• sampling methods

  • usually destroys sample

• analysis

• preservation

  • max preservation under PERFECT conditions = 6.8 Ma

  • usually unreadable by 1.5 Ma

  • oldest hominin so far = 430 Ka (H. heidelbergensis)

Ancient Genetics History

• Human Genome Project = 2003

• ancient DNA from H. sapiens, H. neanderthalensis, Denisovans, H. heidelbergensis, P. robustus)

Neanderthal DNA

• shows interbreeding w humans

  • 1-4% outside of Africa

• FOXP2 gene = language

• gone by 40Ka

  • absorbed into larger H. sapiens pop.?

Denisovans

• Denisova cave in Russia

• first hominin to be identified by DNA ALONE

  • mDNA distinct from Neanderthals and modern humans

  • “cousin species”

• also interbred with humans

• no full skull found (cranial capacity unknown)

H. sapiens

• “wise man”

• found everywhere

• 300Ka-present

• traits

  • FLAT faces

  • less facial and skeletal robusticity

  • tall and round brain cases

  • CHIN AND FOREHEAD

Regional Continuity Model

• least supported by current evidence

• H. erectus leaves Africa → populations evolve into H. sapiens independently → CONTINUOUS GENE FLOW PREVENTS H. SAPIENS SPECIATION

• amount of gene flow is probably implausible

Complete Replacement Model

• “Out of Africa” model

• H. erectus → H. heidelbergensis → H. sapiens in Africa (300-200Ka)

  • implies NO INTERBREEDING

• European H. heidelbergensis → Neanderthals

• somewhat supported by material record

• NOT supported by genetic evidence

Partial Replacement Model

• MOST supported by current evidence

• genetics shows evidence of interbreeding

• H. erectus → H. heidelbergensis in Africa

  • heidelbergensis in Europe → Neanderthals

  • heidelbergensis in Asia → Denisovans

  • heidelbergensis in Africa → H. sapiens

• enough isolation for physical difference but NOT enough to prevent interbreeding

Earliest H. sapiens

• oldest accepted from Ethiopia (233 Ka)

• oldest possible in Morocco (315 Ka) (not yet sure, definitely Homo)

• more robust on avg. than modern humans

H. sapiens Dispersal

• Middle East by 115-80 Ka

• Europe by 65 Ka

  • overlap w Neanderthals in both ME and Europe

• Australia by at least 50 Ka (rafts or boats)

• Americas by at least 15 Ka (potentially 25-30Ka)

  • Bering land bridges or coastal migration

  • Paisley Caves, Oregon (oldest bio evidence)

  • Kennewick Man (9.8 Ka)

Describing Human Variation

• vary in phenotype

• GENETICALLY HOMOGENOUS

• historically: race/racial classification

  • assumed racial categories = discrete and homogenous

  • variation culturally in how race is classified

Linnaean Approach to Human Variability

• Carolus Linnaeus

  • H. sapiens afer = Africa

  • H. sapiens asiaticus = Asia

  • H. sapiens europaenus = Europe

  • H. sapiens ferus = “wild men”

  • H. sapiens monstrous = those w congenital conditions

Biological Determinism

• skin color, head size/shape, facial shape, geography → PERCEIVED INTELLIGENCE AND BEHAVIOR

• phrenology (skull shape)

• inaccurate association of behavioral attributes w/ biological traits

Johann Blumenbach Approach

• “father of physical anthropology”

• defined “classic races” (using skull shape)

  • Caucasian

  • Mongolian

  • Ethiopian

  • American (native)

  • Malay

• field moves toward anthropometry

  • measurement of human body (standardize quantitative methods in ANTH)

Race as a Social Concept

• problems

  • biologically inaccurate

  • not useful for classification (no more info about evolution or history)

  • historical baggage (laws, justify human mistreatment)

• doesn’t deny existence of human biological variation

• race = powerful social category for scientific analysis through race relations in our society

Historical Applications of Biological Determinism

• justification for imperialism and colonialism

• EUGENICS = prioritization of certain people to reproduce over those who “shouldn’t”

  • forced sterilization in USA (not federally prohibited)

  • famously employed by Nazi Germany

Sociocultural Race

• biocultural approach = not simply descriptive, race is social construct BUT still maintains importance in culture and society (still exists)

• “Sociocultural phenomenon” affecting lives = HEALTH DISPARITIES

Human Genetic Variability

• extremely genetically homogenous

• more variation WITHIN than BETWEEN populations

• most human variation within Africa/African populations

Human Physical Variabilty

• H. sapiens = polytypic species

• intraspecies variation

  • skin color

  • body proportions

  • face shape

  • eyes

  • hair texture

  • lactose tolerance

  • lung capacity

Clinal Distribution

a lot of physical traits vary non-randomly with a geographic pattern (continuous variation over geographic space)

ex. lactose intolerance (reproductive advantage to consume food w lactose, availability of lactose)

Climate Adptations

• hot and dry = getting rid of heat (small body mass, long appendages, reduced insulation/less fat)

• cold = retention of heat (relatively larger mass, short appendages, increased insulation/visceral fat around organs)

Skin Color

• most commonly used trait for racial classifications

• varies by clinal distribution

  • melanin = pigmentation protein

  • latitude? UV and solar radiation

High Sunlight Environments

• darker skin advantage

  • protection against folate depletion (melanin protects folate systems)

    • essential for DNA synthesis, spermatogenesis, embryogenesis, and neural tube development

  • minimal (but there) protection against sunburn

    • incorrect skin cancer hypothesis (after reproductive age)

  • protects against UV rays

Low Sunlight Environments

• lighter skin advantage

  • increased Vitamin D synthesis (not supplemented by sunlight)

    • calcium absorption

    • immune funciton

    • deficiency = rickets/bone-softening

  • less susceptible to frostbite

  • EXCEPTION: Inuit populations have darker skin bc vitamin D supplementation from traditional diet (despite northern latitude)