FINAL EXAM Study Guide Flashcards
Characteristics of Homo
Plio-Pleistocene genus of hominin historically defined by:
- relatively larger brain
- loss of prognathism
- derived limb proportions
- larger stature
- less dimorphism
- smaller molars and premolars
- smaller, more delicately built faces
- parabolic palate (not U-shaped)
- associated with stone tool technology
(Oldest fossils assigned to the genus Homo are about 3 Ma)
Cranial capacity of Homo
600 cc (bigger than ape-sized) to 800 cc
- species in the genus Homo have larger cranial capacities than australopiths
- OH 24 est. 590 cc
- KNM-ER 1813 est. 500 cc
- cranial capacity of earliest Homo as large as 800 cc
- KNM-ER 1470 est. 775 cc
Dentition (dental arcade shape) of Homo
More parabolic (NOT primitive U-shaped)
-shorter, wider arch
-Reduced subnasal prognathism is related to the change in tooth and jaw structure
Limb proportions of Homo
More derived
- relatively long legs, shorter arms
A lot of what we know about early Homo body proportions come from the Homo erectus partial skeleton “Nariokotome Boy”
- larger-bodied (over five feet and over 100 lbs)
Human-like proportions of arms and legs
- shortened forearms
- elongated femora and tibiae
- shoulder like modern humans
What is the oldest evidence for human body proportions (relatively long legs, derived upper arm hand and shoulder morphology)
More modern body proportions first appear at around 1.8–1.5 Ma, with Homo ergaster (early African Homo erectus), represented by the Nariokotome skeleton KNM-WT 15000, in which the legs were considerably longer in relation to the trunk than they are in human adults, although this skeleton represents an adolescent
What is the oldest stone tool industry proposed? How old is it? Which hominin group would that be associated with?
2.5 Ma The Oldowan Lithic Industry (until recently) was seen as the oldest and simplest stone tool technology
- few flakes from unprepared core
- choppers
- mostly unifacial
> 2.5 - 1.76 Ma
Lokalalei, Kenya at 2.3 Ma
Gona, Ethiopia at 2.5 Ma
Even at old sites, the flaking is well-executed
Oldowan tools were probably used for a variety of applications:
- processing plant material
- extracting marrow (scavenging)
- cutting meat (scavenging or maybe hunting)
*Associated with Homo habilis!
(*The Lomekwian Industry was recently proposed; hitting stones together probably in Australopithecus…)
Oldowan
The Oldowan Lithic Industry was seen as the oldest and simplest stone tool technology
- few flakes from unprepared core
- choppers
- mostly unifacial
Associated with Homo habilis
Acheulean
(1.8 Ma) Beginning 1.76 Ma Acheulean appears
The Acheulean is defined by:
- handaxes present
- bifacial flaking
- shaped objects
Hunting or scavenging?
- cut marks superimposed over tooth marks
- use wear analysis: primary use is processing vegetal materials plant foods
More carcasses than Oldowan sites
- more success at scavenging
Raw material transport
How to the two (O an A) lithic industries differ? Which hominin group are each associated with?
The Oldowan lithic industry is characterized by simple stone tools, such as choppers and scrapers, while the Acheulean industry is known for more complex tools like handaxes and cleavers. Additionally, the Acheulean industry is associated with Homo erectus, while the Oldowan industry is associated with earlier hominins like Homo habilis
When did hominins first leave Africa? Where did they go?
Homo erectus is the oldest hominin species to be found outside of Africa
When? This happened at 1.8 Ma
Where? Asia and Europe
How old is the oldest convincing evidence of fire in the archaeological record?
Schoningen is an Archaeological site in Germany dated to ca. 400 ka
- this amazing site preserves long wooden spears
- butchered horses indicate hunting likely took place
- some researchers consider this site to preserve some of the earliest evidence of fire (charcoal, charred wooden tools, heated flints, etc. BUT the evidence for hearths is not clear)
Describe how archaeologists and paleoanthropologist can study the emergence of hunting vs. scavenging in hominins
How complete are the animal carcasses found at archaeological sites?
Are the bones of the carcasses covered with carnivore tooth marks? Stone tool cut marks?
How do isotopes help us identify meat eating?
- Nitrogen isotopes are helpful for understanding trophic level
Classic neanderthal features (describe two of them and describe how they are related to the Accretion Model)
Taxonomically distinguished by
- long, low braincase
- face projecting along midline (receding zygomatics)
- double-arched brow ridges
- large nasal aperture
- suprainiac fossa
- occipital bun
- “en bombe” shape
- no canine fossa
- no chin
- retromolar space
- morphology of the inner ear
Accretion Model: proposes that the features accumulated over a long period of time; therefore, all of those features would not be present in the earliest Neanderthals
- earliest ancestral populations over 400 ka show a few of these features but not all of them
HOW were Neanderthals ADAPTED to live in COLD climates? (also include behavioral adaptations)
Occupied Europe during glacials and interglacials
Characteristics of post cranium
- difference in overall stockiness
- adaptation to cold environments include thermoregulation and body’s volume:surface area ratio
- body proportions that include broad trunk and short distal limb
Neanderthals had mastered fire
- used to heat flint
- hardening spear points
- create adhesive
- warm themselves
- cook food
- ward of predators
- hunt (in the dark)
What kinds of tools did Neanderthals use?
Formidable hunters, using stone-tipped wooden spears, lissoirs to process animal hides, stone tools held together by multi-component adhesive, etc. to hunt bigger animals, such as the woolly mammoth????
Neanderthal behaviors
Fire use
Hunting (meat consumption)
Skin preparation
Symbolic behavior (eg. Burniquel Cave)
When did Neanderthals go extinct?
They disappeared around 40,000 years ago, around the same time the anatomically modern Homo sapiens emerged from Africa
When and where did anatomically modern humans evolve?
Middle Stone Age (MSA)/Middle Paleolithic sites
Middle Pleistocene hominins in Africa
How do we know that our species evolved in Africa (what is the evidence?!)
Fossil and DNA evidence
-Ex. Genetic data point to an African origin of all modern humans living today
- the rich genetic diversity in Africa is because Africa holds the source populations for a series of dispersal events
What is the difference between anatomically modern Homo sapiens and behaviorally modern Homo sapiens (ex. What is the LSA?)
Late Stone Age (LSA) Behaviorally modern humans:
- larger, denser populations
- different kind of tools (bone tools; blades and bladelets)
- projectile weaponry
- fishing and marine foods
- improvement in extracting resources from environment
- aesthetics and abstract representation (art, jewelry, tailored clothing)
- regionally distinct cultural materials
*The main difference between anatomically modern Homo sapiens and behaviorally modern Homo sapiens lies in their cognitive abilities and technological advancements. The Late Stone Age (LSA) is a period associated with the development of advanced tools, art, and symbolic behavior by behaviorally modern humans.
When and where did behaviorally modern humans evolve?
Africa: Later Stone Age (LSA)
Europe: Upper Paleolithic
When did behaviorally modern humans leave Africa?
Found outside Africa shortly after 50 ka
- Bacho Kiro Cave, Bulgaria contains the oldest European behaviorally modern human currently known
Did Homo sapiens, Neanderthals, and Denisovans interbreed? How do we know that?
Yes
To figure this out, they looked at mtDNA, 1997 (just from mother)
- All Neanderthals had different mtDNA sequences than modern humans
HOWEVER… in 2010, looked at nuclear genome (mother and father)
- found a small amount of admixture; “Neanderthal alleles” in European and Asian populations, but not in African populations
- Genomes 99.7% similar
- Therefore, they were interbreeding, just not very much and that this interbreeding was only happening outside of Africa (higher in European and low in Asia)
Why does human skin come in different shades?
Melanin
- skin color depends on how much and which type of melanin is produced
Melanocytes
- cells that make melanin
- embedded between the basal layer and the overlying stratum spinosum
Melanosomes
- as melanosomes fill up with melanin, the pigment gets distributed to new skin cells through the dendrites
Eumelanin
- molecule responsible for most variation in human skin pigmentation; concentration counts for skin’s darkness
Pheomelanin
- accounts for skin’s reddish-brown-yellow color
Human skin pigmentation is an example of a polymorphic, polygenic, continuous, and complex phenotype… describe all these words and how they relate to skin pigmentation
Polymorphic refers to the variety of skin tones found among different populations, while polygenic means that multiple genes contribute to determining skin color. The continuous nature of skin pigmentation means that there is a wide spectrum of shades, and the complexity arises from the interactions between genetic and environmental factors influencing melanin production
Skin is an organ… what functions does it carry out?
Protective barrier
Thermoregulation (cooling via sweating)
Vitamin D synthesis
What does UVR exposure do to (and for) our bodies?
UVR over-exposure damage to human body
Vitamin D
- immune system function
- bone mineralization
*UVR has the potential to alter biological processes:
- Can damage the skin
(sunburn – caused especially by UVB)
(destroys skin elasticity – UVA)
- Can damage molecules and compounds inside the body (and cause Melanoma)
- Breaks down folate, a very important vitamin
Positives:
- UVR can catalyze production of compounds inside the body
- UVB exposure initiates provitamin D production
TOO MUCH UVR:
- sunburn and impaired ability to cool body via evaporation
- folate destruction and associated reproductive consequences
- cancer
POSITIVES of UVR:
- Vitamin D is important for strong bones and normal skeletal development
- Vitamin D is important for immune system health
Why did darkly pigmented skin evolve? (Folate hypothesis!!!!)
The folate hypothesis suggests that darkly pigmented skin evolved in order to protect against folate depletion caused by UV radiation. This adaptation allowed humans living in sunny environments to maintain healthy levels of folate, crucial for reproductive success
Why did lightly pigmented human skin evolve (Vitamin D hypothesis!!!!)
The Vitamin D hypothesis suggests that lightly pigmented skin evolved in response to the need for increased vitamin D synthesis in regions with limited sunlight. This adaptation allowed early humans to efficiently produce vitamin D, essential for bone health and immune function even in places with limited sunlight
How is the discipline of physical anthropology related to early race studies?
The field of physical anthropology has a long history of attempts to justify racism scientifically
- one preoccupation was determining the number of races
- a related aim was to rank the races in terms of how “evolved” they were
What is monogenism and polygenism?
Monogenism
- the idea that all humans share a single common origin
Polygenism
- idea that the different human races had different evolutionary origins
- races as different species
What is the classical race concept?
A geographic variant/sub-species/species of Homo
These groups are defined by physical characteristics
- skin color
- hair color and texture
- eye color and shape
- other facial features (nose and lip shape)
These groups are discrete, stable, and deterministic (WHICH IS FALSE)
Biological determinism?
The prejudiced belief that our sex and race are determined by our biology (genetics, phenotype, skeletal traits, etc.)
How have scientists challenged the classical race concept? (Be able to describe some arguments against…)
Every population has many different phenotypic variants, and most populations carry most alleles
Gradient-style distribution of human variation
Instability of racial groupings
Genotype-phenotype non concordance
Genotype-phenotype non concordance…
Think about the parents of Sandra Liang, who clearing both carried African population alleles but did not look “mixed race” phenotypically
Think about the story of Wayne Joesph, the Black man who does not carry African population alleles
Human phenotypic and genetic variation can be non-concordant
An example of concordance between phenotype and genetic variation: I can look at your skin color and guess your genotype
Non-concordant: Different phenotypic traits can have different distributions; also, genotypes and phenotypes can have different distributions
You can carry alleles that are not expressed in the phenotype so it is crazy to judge race based on appearances…
What does it mean to racialize a group of humans?
Racializing a group of humans involves attributing certain characteristics or stereotypes to them based on their race, which can lead to discrimination and unequal treatment
