-
Macroevolution
creation/appearance of new species over long period of time
-
phyletic transformation
conversion of a species into a new species Over long periods of time
-
cladogenesis
- “branching” evolution – splitting of a species
- 2 Types of Cladogenesis:
- 1) Allopatric speciation - production of new species by branching of existing ones
- 2) Parapatric Speciation - in the context of overlapping ranges
-
adaptive radiation
- Adaptive radiation: expansion and diversification of life forms into new ecological niches.
- ex: lemurs: Lemur separation/Madagascar/ only live in Madagascar/
- Two factors: Species has to have adaptive potential; Some species are more adaptable than others and they must have adaptable opportunities
-
hominin
group consisting of modern human beings and immediate ancestors (after split with chimps)
-
hominins emerged and migrated out of where
africa
-
relative dating
- soil strata reflect relative age
- Youngest layer on top of oldest layer
- Earthquakes can cause oldest layer to come up to the top
- Law of superposition Principle that the bottom layer in stratified deposit is the oldest (normally)
- Bottom layer (of earth) is the oldest
-
absolute dating
- gives calendar year
- BP (before present/ before 1950) - Why before 1950 Atomic bomb helped us learn nature of isotopes
- MYA (million years ago)
- BC/AD = BCE/CE (common era is what we use now )
- BC/BC (before Christ)
- AD/CE (anno domine common era)
-
Potassium-Argon
- Based on conversion of atoms in one form to the other
- Based on decay of radioactive 40K (solid) into 40AR (non-radioactive gas)
- Decays at steady rate
-
Fission-track
- Based on radioactive uranium
- Molten rock has radioactive uranium in it
- After hardens, uranium violently fissions: makes fission tracks in the stone
- Then you Get sample: count number of tracks to get amount of time since rock has formed
- dates when the rock was formed not the actual fossils itself
-
cross-dating
- Combines both relative and absolute dating
- Association of remains with something of a known geological age
-
isotope
specific variant of an element
-
-
Paleoanthropology
study of human emergence
-
prognathism
lower face and jaws project in front of upper face
-
Australopithecine trends
- 1: more efficient bipeds
- 2: dentition changed - thicker enamel, bigger molar teeth, robust forms: “megadonts”
- 3: limited brain development not much significant increase in brain size.
-
Australopithecus afarensis
- 8-3 mya
- more apelike - long limbs
- from pelvis down, typical of modern humans
- prognathic
- thick enamels
- large canines
- stronger than modern humans
- brain 420cc
-
Lucy
- A. Afarensis
- 40% complete
- discovered by D. Johanson
- short femur angled inward
- Short (3.3 ft. tall)
-
-
Paranthropus boisei
- Found by Mary and Louis Leakey in Olduvai Gorge 3-1.2 mya
- huge molars: thick enamel
- Brain : 510cc
- Dimorphic F: 75 lbs, 4 ft M: 108 lbs, 4.5 ft Sexual dimorphism index = 69
- Prominent sagittal crest “nutcracker man”
- robust forms: Ultimate grinders Lived in mixed grassland and woodland : vegetarians
- Nuts, seeds, tough fibrous foods Huge teeth and jaw muscles for crushing, grinding and chewing
- Extinct 1 mya
- Became way too specialized
-
Things associated with Homo habilis and Homo rudolfensis
- Oldowan tradition
- Flintknapping
- isotropic
- reductive technology
-
H. habilis
- Larger brain ‘case’ & Brow ridges
- 2.5 – 1.8 mya
- Compared to australopithecines:
- Larger brain-to-body size ratio
- flat face
- Jaws and teeth are smaller
- Brain size 650cc
- Dimorphic
-
H. rudolfensis
- Brain 750cc
- 5ft tall
- dimorphic
- less prognathic
- broader face
-
H. habilis/rudolfensis
- 1st stone tool makers? Question of if they are the first tool makers
- Biocultural evolution - Reduction in jaw size and teeth -> replacing biology with technology Expanding diet breadth with higher quality foods Ex: bone marrow – also has really high fat content Fueled brain expansion?
-
Homo ergaster
- discovered in africa
- 2 mya
- 5-6 ft
- Brain size 950
- Long cranium (different from humans), not as much height ; elongated occipital bun
- Large brow ridges
- Forward projecting nose
- Intermediate between austra & humans Adapted to softer food
- Controlled source of fire; cooked food; softer food; tooth reduction (example biocultural evolution)
- Speedy
- Slender
- Ample surface area for sweating to keep body temp controlled
- Good in the tropics
-
Homo erectus
found in eurasia
-
-
Java Man
- discovered by Eugene Dubois
- early homo erectus find
-
Zhoukoudian
- dragon bone hill
- davidson black went to look for missing link
- Remains of 40 individiuals found
- We don’t have them anymore because it was loaded on a submarine that was never seen again bc of the advent of WWII
- Plaster casts of all the crania were made though
- Brain size average: 1000 cc 900cc – 700,000 1000 – 200,000
- Over time, marked increase in brain size
-
-
Oldowan
- 2.5-1mya
- 1st stone tool tradition
- Named after Olduvai Gorge
- Simple cobble chopping tools made out of stream cobbles
- Make course cutting edge by removing a few flakes
- Both tools and flakes are important
-
Acheulean tradition
- multipurpose tool
- handaxe - pear shaped
-
Abbevillian handaxe
- part of achulean technology
- discovered in france
- teardrop shaped
-
Acheulean handaxe
multipurpose tool
-
Why could H. erectus migrate
- Smarter (larger brains)
- Better tools (Acheulean handaxes)
- Evidence for Fire and Shelter
-
thoracic vertebral foramen
- nariokotome boys throacic foramen smaller than modern humans
- received less information or less responsive of the world around him
- homo erectus have smaller vertebral foramen becuase
- It was speculated that bipedalism was related to this, but there was already evidence for bipedalism for more thn 6mya
- so, he speculated it had something to do with speech
-
Nariokotome Boy
- 7 mya
- homoerectus famous find
- Almost full skeleton
- Discovered by Kamoya Kimeu in 1984
- 8 year old boy
- 5ft 3” tall
- suggests that homo erectus had a growth spurt much more earlier
-
Broca’s area
- Broca’s area = speech center – has role in speech, but is not “The role”
- Able to identify homo erectus brocas areas bc of the endocast made bc the brain Leaves imprint on skull
- Erectus skulls have imprint = Early assumption, erectus had speech
- Speech originates in Wernicke’s area
- Not going to find imprints of this because its in the inside of the brain
- It sends messages to the Brocas area
- Today we know the Broca’s ares is associated with more than speech “Important speech area” in brain NEXT to broca’s area
- Erectus probably did not speak like us
- Speech did not develop with homo erectus
-
associatied with archaic H. sapiens
- Mousterian tradition
- Levallois technique
- H. sapiens neandertalensis
- Shanidar
-
Mousterian tradition
- more complex form of toll compared to achuelean
- reductive technology
- includes the levellois technque
-
Levallois technique
- out of mousterian tradition
- Turtle back core
- Carefully shaped chunked with removed blanks Stone tools have life cycles and often reused
- can make projectile points
- good for cutting, slicing, butchering
- more specialized for different jobs compared to achulean multipurpose tool
- more cutting edge per raw material compared to achulean
-
H. sapiens neandertalensis
- dates to 125,000-40,000BP
- Middle Pleistocene hominin
- 1st discovered in 1856 Neander valley
- Remains found in Europe and middle east
- Low skull, lack of chin, brow ridges
- short, stocky
- 140-180 lbs
- large brain
- worn down incisors probably used as tool
- adaptive to cold climate : big nasal cavity, barrel chested, large brain attributed to adaptation to cold climate
- popular conception is that they were brutish and stupid
-
Shanidar
- site of deliberate burial
- Earliest example of Ritual burial
- Left side of head bashed hard
- Right side of body slammed in traumatic event
- soil samples underneath skeleton showed pollen samples indicating body layed on bed of pine bows bouquets of flowers
-
Anatomically Modern Homo sapiens (AMHS)
-
Mitochondrial DNA
- replacement model
- AMHS populations have most genetic diversity; should be the oldest most ancient ones.
- mDNA diversity is a result of mutations; oldest population should have most mutations otherwise it would not be diverse and has been evolving longer.
-
Christopher Stringer
- idea that we came out of Africa and replaced everyone else and that no interbreeding took place
- idea that Homo erectus populations in Africa gave rise to AMHS in AfricaThen, AMHS migrated to Europe and Asia, replacing h. erectus and Neandertals populations in Europe and Asia
- Humancentric model because it places us by ourselves and that we outcompete these other homininsfossil evidence: Oldest AMHS fossils in Africa. It fits because its Consistent with African Genesis.
- mDNA: AMHS populations have most genetic diversity; should be the oldest most ancient ones. mDNA diversity is a result of mutations; oldest population should have most mutations otherwise it would not be diverse and has been evolving longer
-
Milford Wolpoff
- regional continuity model
- AMHS evolved at the same time in major regions of the old world (Africa, Europe, and Asia)
- Some gene flow between populations would be neededMix with AMHS (coming out of Africa), and AMHS derived from European Neandertals and asian h. erectus populations
- Problem if this model were true: is that not a lot of gene flow back to Africa
- No evidence there was migration back to Africa because you cant get populations remixing in Africa without gene flow
-
middle ground view
- Partial replacement or “assimilation model” of archaic groups
- neanderthals interbreed, but swamped out genetically
- Most DNA from AMHS migrating out of Africa
-
Upper Paleolithic
- 40,000 - 10,000 BP
- shift to AMHS
- climate change becuase of ice age
- population increase was extremly rapid due to more sites
- humans widely dispersed
- subsistence base broadens because huge animals started to die so they needed to diversify their food
- artistic explosion
- production of blades to make different specialized tools
-
Bering strait
- 50,000 year general accepted date becuase its the first time there was an ice free corridor
- it didn't take long for people to get to the tip of south america
-
4 tenets of stone tool
- stone topography -
- platform preparation - get ride of sharp edges because of risk of damaging
- angle of force - important becuase possibility of cutting biface in half
- amount of force - important for taking off pressure flakes - hammerstone determines type of flake and pressure needed
-
blade technology tradition
- associated with late upper paleolithic period
- Specialized for local resources for Hunting marine and land animals
- more efficiency and multiple traditions
-
What kind of qualities of each tradition makes each previous more efficient than the other?
- tools were specialized for local resources
- its more than just imitation, its teaching
- ability to communicate better
- more efficient technology
- techniques associated with these traditions were more effecient than previous one
-
Venus figurines
- portable artwork
- heavy set female bodies with exaggerated body parts
- possibly symbolic of being well fed and having good fertility
-
Dolni Vestonice, Czech Republic
- Mammoth bone huts
- Ovens for food and figurines
- Shelter made of mammoth bones
- No trees to use because lack of forest areas to make shelter out of wood
- Use all the parts of the animal
- Type of Cultural innovation
-
Lascaux cave
stags, horses, and ibex found in peripheral galleries
-
sympathetic Magic
- Mostly big game animals with Darts/points in or near them
- we dont really know what it means, but probaly had to do with hunting and that the paintings were only done by men
- ex. hand prints could show sexual dimorphism
-
Race
- traditionally, there were only a few races that were bounded geographically
- problem with this is that genetic traits dont bundle - natural selection requires variation in gene pool, arbitrary which traits are valid, and theres more variation within groups than between groups
- we acknowlede outward phenotypic differences, but there is no good patterning in skin color because of colonialism and movement of people everywhere
-
cline (clinal)
- gradual shift in genetic traits over space
- example Skin color: poles to equator, gets darker
- Blood: type B increases from west to east Europe
- These are a result of gene flow and natural selection
-
polytypic/polymorphic
- humans have different types and forms
- lots of diversity and variation within regional populations and local populations due to adaptation of their different environments
- no difference in terms of genetics despite phenotypic difference
-
Monogenism
theory that human origins all share the same pair bond/common descent for all human races
-
Polygenism
- human “races” from different pairs
- different physical, mental, and moral attributes
- ex. Linnaeus was a polygenist Blacks were limited Whites were superior
- Associated with biological determinism
- Polygenic people said : phenotypic varaiation associated with intelligence, morals, etc.
- Result of eugenics
|
|
