ANTH FINAL Part 3

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Hunters or Scavengers?

1. Most of the bones associated with early Homo are nonmeat bearing bones that have been smashed to getmarrow. Likelyscavengedfromkillsmadeby other animals 2. Most of the cut marks are found on the shafts of bones suggesting that the bones had already been separated from the carcasses. 3. Cut marks on the bones sometimes overlie carnivore tooth marks. If the hominids had got there first it would have been the other way round

Why are Neanderthals the best known ancient humans?

1. They are ancient Europeans- most paleoanthropologists are of European descent and like to study their own people 2. They are found in Europe- sight seeing and food

Homo habilis

1.9-1.4 MYA • East Africa (Kenya, Tanzania) • Stone Tools Markedbrowridge • Short,prognathicface • Brain600-700cc • Smallermolars

Homo rudolfensis

2.4? - 1.6? mya • Kenya Lessbrow • Longer,flatterface • Brain775cc • Largermolars

Uranium-Thorium Dating (U-Series Dating)

AKA "U-Series" dating. • Absolute dating technique • Measures the degree to which the two isotopes meet equilibrium after deposition • Upper age limit of 500,000 years • Used to date minerals deposited at the time a site was occupied (usually caves) or encrustations on bones • Uses small samples

Homo neanderthalensis

BOTH FOSSIL AND GENETIC EVIDENCE INDICATE THAT NEANDERTHALS AND MODERN HUMANS EVOLVED FROM A COMMON ANCESTOR BETWEEN 500,000 AND 200,000 YEARS AGO. • THAT COMMON ANCESTOR IS LIKELY HOMO HEIDELBERGENSIS • CLASSIFICATION ISSUES - EITHER HOMO SAPIENS NEANDERTHALENSIS OR HOMO NEANDERTHALENSIS 130-80kya Europe and SW Asia "Classic Neanderthals" date 70-35kya First found in the Neander Valley in Germany in the early and mid 19th century Thought to be ape-like "missing link" Early researchers emphasized their primitive over modern characteristics La Chapelle-Aux-Saints - The La Chapelle specimen found in France in1908 and examined by Marcellin Boule, famous paleontologist in 1911 - Boule reconstructed Neanderthal man as bent over, having divergent big toes 1957 reexamination shows Boule ignored severe osteoarthritis that contributed to its less than upright posture - divergent toes and some other primitive features were conjecture, as specimen was very fragmentary - damage had been done- idea of primitive, departed Neanderthal Man was firmly lodged in popular consciousness • Neanderthals and Archaics have a more pronounced dip between the browridges than H. erectus • Skull is higher and more rounded (no sagittal keel) • Face and jaw not so massive Neanderthals have bigger skulls with long, low crania Bigger brains than modern humans at 1300-1640CC while modern humans average 1350cc Organization of the brain is different - larger frontal lobes and larger occipital area than H. Sapiens Neanderthals have mid facial projection and large nasal passages - large front teeth, bony faces, large brow ridges - some neand. Have occipital bun where back of the skull projects outward - bodies are shorter and stockier than most humans - Very robust bodies with thick bones, heavy muscle markings Why differences? Why mid facial projection and large nasal passages? - adaptation to glacial conditions?- help warm air before inhalation If this were true, we might expect modern people who live in very cold climates also to have big noses and mid facial projection. Modern Arctic peoples tend to have small noses and flat faces - teeth as tools? Lots of people used their teeth as tools right up to modern times (As with the Inuit in this picture) But they did not develop mid facial projection LATEST THEORY: Genetic Drift- random genetic change is primary source of most cranial differences b/w two species Few sites older than 100k and most are b/w 80-40kya Environment of Europe was mostly Tundra- low bushes and shrubs, moss, lichen Pleistocene Megafauna- very large versions of modern animals now extinct - Cave Bear, Woolly Mammoth, Sabre Toothed Tiger New Technology MOUSTERIAN Technology - made flakes using the levallios technique of preparing cores - Levallios technique: one type of prepared core tech - core prepared to specific shape, 3-5 flakes of a particular shape can be taken off Retouching: chipping off little flakes to change the shape of an edge or make it stronger - in Mousterian Tech, flakes made by levallios technique are retouched into a variety of tools: scrapes, knife, point Use Wear: analysis of the working parts of a stone tool - may have been first to make stone tipped projectiles or thrusting spears Halting: piece of stone inserted into notch in wooden shaft, stabilized with gums and resins, secured in place by tightly wrapping with sinew or gut Subsistence: Lewis Binford lived among the Inuit to understand life in the Tundra- Ethnoarchaeology - Learned about disruption of cut marks on bone when it has been butchered - similar patterns seen from Neanderthal sites - UMM EL TLEL, Syria- Mousterian point embedded in neck of wild donkey - Bones found predominantly upper leg- choice cuts would not have been left by carnivores - few gnaw marks but lots fo cut parks - breakage for marrow removal - focus on single animal type - Neanderthal shave nitrogen levels of carnivores Evidence for sick and elderly in ideals who could not have survived or healed without intensive care from others - SHANIDAR, IRaq- blindness and loss of use of one arm, lived for many years Aesthetics - perforated teeth's nd viceroy - Ochre for pigments Neanderthal Flute - Slovenia 82-43kya - bear femur with four holes in it Burials - purposely positioned often with grave goods, indicating surplus SHANIDAR: flexed burial, pollen samples show pine and wild flowers - grave goods include: animal bones, horns, stones, tools, seen 40% of time Don't; live in caves b/c home to other creatures, cold and damp Most settlements at the mouths of certain caves- those with southward facing entrances - important during coldest times of year as they provide light and warmth - lived in tents and shelters during warmer times of year Moula Guercy- cut marks on human remains indicate cannibalism

Australopithecus afarensis

Dated 3.8-3.0 mya • Ethiopia (Hadar) Tanzania (Laetoli) • Well known species - many individuals from many sites... Lucy ThemostfamousspecimenofA. afarensis • DiscoveredinEthiopia(Hadar)in 1974 by Don Johansen • 40%Complete • Datesto3.2MYA • Muchofwhatwe know about the australopithecines comes from studying the Lucy specimen Many Similarities to Miocene apes suggesting relatively recent divergence from period apes • But differences too that suggest afarensis may be an important ancestor of more recent hominins Dentition: A. afarensis has front teeth that are smaller than ape teeth but larger than modern humans. • Molars are very large A. afarensis has canine teeth that are smaller than a gorilla but larger than modern humans Gorillas have large canine teeth that "lock" when mouth is closed - jaw can't chew side by side Smaller front teeth facilitate side to side motion while chewing Rotary chewing • A. afarensis displays prognathism - where the lower face is projected forward • Modernhuman faces are much flatter • Dentitionstudiesof other A. afarensis children suggests slightly slower maturation rates than modern apes • Suggestsagoodperiod of dependency and emphasis on learning Skulls: Massive jaw A. afarensis reconstructed skull • Flaring cheekbones with big zygomatic arches • Some fossils have a hint of a sagittal crest: Finofboneatthetopofthe skull for the attachment of chewing muscles • Animals with large sagittal crests also have big jaws • Habitually chew tough foods Reductionoffrontteethand increase in size of molars suggests a diet of hard fibrous vegetation requiring lots of chewing • MolarMicrowearanalysis shows that hard and brittle foods were part of the afarensis diet but not as important as soft foods (fruits and vegetation) • Suggestshardfoodsnuts, vegetation and roots would have been consumed rarely during off-seasons and droughts Chimps and Australipiths have large Supraorbital torus (brow ridges)- humans do not Brain Size: Average 430cc, slightly larger than chimp Post-Cranial Skeleton Decidedly human • Clearly bipedal (pelvis, hip, leg and foot) • But qrms are longer than humans LAETOLI (Tanzania) Footprints Footprintsinvolcanicash and then covered with more ash • Ashdatedto3.6mya (dated with K/Ar) • Madeby A. afarensis • 2individuals one large and one smaller. Printsshowabipedalgaitwas "heel-strike" (heel of the foot hits first) followed by a "toe-off" ( toes push off at end of the stride) • Theclosespacingofthefootprints are evidence that the people who left them had a short slow stride. • ThismeansthatA.afarensis probably had short legs. • Onlymuchlaterthatearlyhumans evolved longer legs, enabling them to walk farther, faster, and cover more territory each day. Researchers suggest a male and a female walking along together • Sexually dimorphic: - Males 12" taller - Males weigh 1.5x females Knee of Australopithecus moved underneath body as in humans A.afarensisbirthcanalis much narrower than human • A.afarensisbabieshad much smaller heads than human babies Curvedfingersandtoes • Muscularuppertorsoand longish arms • Bothsuggestarboreal orientation - A. afarensis likely slept and spent a significant amount of time in trees in addition to walking bipedally The First Family Found 1975- the year after Lucy • 6-12 A. afarensis individuals who all died at the same time • Cause is unknown - Flood? Earthquake? Surplus killing by predators? • Adults and children, males and females • An excellent opportunity to understand variation, dimorphism and maturation New Information Mammal bones with stone tool markings? • Found in an A. afarensis contexts suggesting this species was beginning to eat meat and that sporadic tool use was beginning! • Problem - no obvious tools identified in 30-40 years of excavation into these sites. Thoughts? - Use of unmodified stones for breaking into marrow? - Bad contextual information on the bones? Skeletally, somewhat transitional with many earlier ape features some of which suggest afarensis was partially arboreal • Lower body (pelvis and legs) were clearly adapted for habitual bipedalism • This was clearly a very successful species and is the best early candidate (so far) in the direct lineage that leads to the Homo genus and modern humans

Homo erectus

Eugene Dubois finds "Java Man" in 1891 in Indonesia (Java) • "Java Man" Dated 1.0 - 0.7 mya OriginateinEastAfricalikelyaround2myaoralittle earlier and evolved from earlier Homo species • H.habilisisoftenatraditionalchoiceasthe forefather of H. erectus but erectus may also have evolved from an unknown common ancestor Homo erectus means "Upright Man" • Dated terminology as we know that H. erectus was not the first bipedal ancestor Cranial Features Long Low Skull with robust features - Projecting lower jaw (Prognathous) - Projecting nose Rear of the skull has a pentagon shape • Widest point of the cranium is very near the base of the skull Large Brow Ridge (Supraorbital Torus) • Narrowing behind the eyes (Post-Orbital Constriction) Nuchal Torus - A bony projection at the rear of the skull where neck muscles attach - Sagittal Keel on top of the skull • Unlike Sagittal Crests, the keel is NOT for muscle attachment While Australopiths have large molars, small front teeth, parallel molars (ape-like), Homo erectus has decreased Molar size, larger front teeth and parabolic dental arcade Teeth as tools: Purposeoftherobust bony architecture of the homo erectus face and head (browridge, nuchal torus, and keel) is unclear... • Itcouldsuggestthatthis species used its teeth as tools which would have required large muscle attachments and heavy bones Brain Brain size ranges 750-1200 ml (average = 1000 ml) = larger brain size than early Homo species • Upper range is near the lower range for Homo sapiens • While H. erectus did have a physically larger brain it is not much larger than previous ancestors when body size is factored in. • H. habilis and H. erectus proportionally had a relatively similar sized brain for their body sizes. ENDOCASTS: Inside surfaces of the skull are negative impressions of the surface of the brain • Sometimestheyoccur naturally like the "Taung Child" skull • Orcanbemadewith latex poured into an empty skull Modern Human Brain Shape Asymmetrical Shape & Specialized Hemispheres • Left side = Language: understanding symbols and abstract ideas • Right side = Spatial Reasoning: hand-eye coordination etc. H. Erectus Brains - Endocasts show that the H. erectus brain possessed a very similar asymmetry as modern humans • Likely possessed the capacity for abstract thought and language Modern humans have specialized areas of the brain associated with speech - known as the Broca's area • EndocastsofH.erectus specimens suggest the presence of a Broca's area - suggesting speech was possible Post-Cranial Skeleton Verysimilartomodern humans with similar like body proportions • Relativelyelongatedlegsand shorter arms than earlier species • ObligateBipeds-lifelivedon the ground had the ability to walk and likely run long distances • Lossofearliertree-climbing adaptations seen in the Australopiths Adult Height: Ranges from 4' 9" to 6' 1" • Adult Weight: Ranges from 88 to 150 lbs • Lots of variation within contemporaneous H. erectus populations (ex. tall and short individuals) • H. erectus exhibits a decreased - but still significant - degree of sexual dimorphism compared to older ancestors Classification - This set of defining physical features are found in a range of fossils that date from 1.9/1.8mya - 500kya and are recovered in Africa, East Asia, SW Asia and Europe • Some physical variation found in different geographic locations (and in different time periods) has encouraged some paleoanthropologists to divide Homo erectus into several species or subspecies. • These paleoanthropologists are known as splitters (rather than lumpers) Since Asian H. erectus fossils were found first (1891) and were the archetypical specimens used to define the species - fossils in Asia keep the Homo erectus classification • African and European fossils each get their own new species designation Homoergaster("WorkingMan") - Limited to Africa - Higher cranial vault, smaller face, gracile build (less robust) - More modern-looking Homo antecessor - Limited to Europe - Modern looking face with small brain • While real physical diversity exists between geographic populations - we are going to largely treat Homo erectus as a single species no matter the geographic origin of the find. Homo erectus in Africa EvolvesinEastAfricaaround2 mya • EarliestFossilsinAfricadateto 1.76 mya from East Turkana - earlier fossils still to be found • LikelysharedEastAfricawith other hominins like H. habilis

Rift Valley of East Africa

Major fault line, place where two continental plates meet, in the process of pulling apart As it pulls apart it exposes layers of fossil bearing geological strata, a great place to search for fossils Rift Valley runs from Afar Depression in Ethiopia, through Kenya, Tanzania, and Malawi East Africa: environmental advantages- soft volcanic sediments = preservation - active volcanoes = dating (K/Ar or Ar/Ar0 - Rift Valley = old fossil exposure

Humans vs Neanderthals

Out Competition = Hunting with better tools and stone technology gives humans a competitive edge, Neanderthals are then forced to relocate or starve Out right extermination of Neanderthals by Humans Environmental Change - Less Glacial Conditions (hyper specialization) Best information suggests it was a combination of environmental change, humans out-competing Neanderthals for resources with some interbreeding This was a big question for a long time Were they separate species and incapable of interbreeding? Could they and did they interbreed? Were Neanderthals absorbed into the modern human lineage? 2009- first draft of Neanderthal genome said unlikely that humans and Neand. Interbred making them a dead end 2010- New work on Neanderthal Genome provides the first Genetic evidence that Neanderthals and humans could and did interbreed Scientists compared Neanderthal DNA to living humans from China, New Guinea, Southern Africa and Western Africa They found that Neanderthal DNA is 99.7% identical to modern human DNA (vs. 98.8% for humans and chimps) They also found that all modern peoples, with the exception of Africans carry 1-4% Neanderthal DNA How? Scientists suggest that modern humans came into contact with Neanderthals shortly after they left Africa, probably around 60,000 years ago in Southwest Asia. From there modern humans migrated throughout the Old World and into the New World carrying 1-4% Neanderthal DNA Non-African individuals carry 1-4% Neanderthal DNA but not all people have the same Neanderthal DNA The population as a whole has about 20% Neanderthal DNA which scientists are using to reconstruct the Neanderthal Genome Although the presence of Neanderthal DNA in human populations suggests that they bred with modern Humans, the very small amount of their DNA suggests that this did not happen very frequently Some evidence that the Neanderthal DNA fortifies a class of immune genes (Human Leukocyte Antigens - or HLAs), which play a vital role in protecting against viruses and infections Advantageous to people migrating into new areas where they were exposed to new pathogens Most Neanderthal DNA in people today relates to Keratin, the protein that makes up hair, skin and nails It likely had an advantage in the colder climates in thicker hair and lighter skin Several genes make us susceptible to: Type 2 Diabetes, Lupus, Crohn's Disease, Seasonal Allergies So much for the myth of the healthy Neanderthal! Admittedly, susceptibility to disease does not mean they actually had it. Neanderthal DNA is not spread evenly throughout the modern human genome There is a significant amount in some places (keratin production) but none at all in large areas of the genome Suggests very infrequent mating. One scientist says as few as 4 hybrids The question of whether Neanderthals and modern humans could interbreed was a question of whether they were reproductively isolated and thus different species The fact that they could interbreed indicates that they are not reproductively isolated and therefore not separate species BUT there is evidence that they were not entirely reproductively compatibl NEANDERTHAL DNA IS PATCHY Neanderthal DNA is not spread evenly throughout the modern human genome There is a significant amount in some places (keratin production) but none at all in large areas of the genome Suggests very infrequent mating. One scientist says as few as 4 hybrids SPECIATION? The question of whether Neanderthals and modern humans could interbreed was a question of whether they were reproductively isolated and thus different species The fact that they could interbreed indicates that they are not reproductively isolated and therefore not separate species BUT there is evidence that they were not entirely reproductively compatible Neanderthal DNA not found in genes that influence testicles or the X chromosome Suggests males with mixed Neanderthal/sapiens parents were infertile All Neanderthal DNA was passed through the female line. Anything related to maleness in the Neanderthal has been purged from our modern genome Interbreeding supports Partial Replacement Model

Pre-Australopiths

Seems that Ardipithecus ramidus may have been an ancestor of the early Australopiths based on physical features and behavioral clues that suggest a direct lineage

Taung Child

Taung, South Africa, 1925 Raymond Dart finds fossil in a box from a limestone quarry - fossil of young individual's face and a cast of brain known as "Taung Child" - ape-like BUT with few significant differences Teeth more human-like and had no canine diastema Foramen magnum was underneath, not at back of skull AUSTRALOPITHECUS AFRICANUS (Southern ape of Africa) - manny initially did not accept Dart b/c of Piltdown However, 1930s addition of evidence of Homo erectus from China and other indication lead to the reexamination of Piltdonw Taung Child- Australopithecus africanus is an early ancestor of humans So is Pithecanthropus erectus now known as HOMO ERECTUS

Bipedal Locomation

This developed first, before large brains and toolmaking Hominins are bipedal hominoids, which are all forms of primates that habitually walk on two legs Habitual Bipeds: walking on two legs is their standard and most efficient means of locomotion Obligate Bipeds: committed to bipedalism and cannot locomote efficiently any other way - human body is designed to walk no two legs - several key parts of body had to change in order to accommodate full time upright movement Foramen Magnum: big hole in bottom of Skull where spinal cord and brain connect, found at back of quadruped skulls and underneath the skull in bipeds Spine Curves: lumbar curve in humans replaces the hunch of previous primates Pelvis: located under trunk, larger and thicker to support weight, larger birth canal to accommodate big brained babies, hip joint reoriented forward and strengthened for wear and tear of bipedal locomotion, more muscles around hips- money humans have a butt Lower Limbs: become longer and more muscular, knees oriented toward center of body Feet: big toe aligned with all the other toes (non-diverging), expanded in three areas- big toe, ball, heel, foot is rigid (while other primates have very flexible and dexterous feet)

Homo heidelbergensis

Widespread in time and space • First named for a specimen found in Germany at Mauer, near Heidelberg • Date800-400Kya • Larger Brain than H. erectus (avg: 1265 ml) • Higher forehead • Smaller face, Thinner bones • Less prognathic than H. erectus • Less extreme Supraorbital tori • Less post orbital constriction behind the brow ridges • This change is due to expansion of the frontal part of the brain Tall and muscular • Some populations averaged 6 feet and 220 lb. • Extensive wear on teeth = used as tools (uneven on right side) • Wear patterns suggest they held things with their teeth and sliced or scraped with their right hands H. heidelbergensis in Africa Several skulls • Much variation • 600 - 125 kya • 1100-1400 cc. • Dating the African specimens has been difficult. Some age estimates have been as old as 800 kya BODO SKULL, Ethiopia Bodo Skull • Dated 600,000 • Transitional Features: - Large Brain 1250 cc very modern size - Robust Skull strong relationship to H. erectus • Has cut marks on the vault, face, and even within the eye orbit, indicating that it was intentionally defleshed. H. heidelbergensis in Europe Several specimens • 600-160 kya • 1200-1325 cc BOXGROVE SITE, England • Boxgrove Site • Human remains are very rare in England; this tibia is one of the few that have been found • Dates to 550 kya • Associated with hundreds of flint handaxes like this one, flake tools, waste flakes and the bones of many butchered animals THE PIT OF BONES, Atapuerca, Spain Near Gran Dolina • "The Pit of Bones" Site (Sima de los Huesos) • Over 6000 hominin bones • At least 28 individuals of all ages • Date 400,000 years The Pit of Bones is a natural 45 foot shaft inside a cave • It has bones of animals that evidently fell in there while seeking shelter • Archaeologists think that the human bones are the result of intentional deposition. They were rather tall and stout on average (cool conditions) • Skulls very similar to Neanderthals • Most of the individuals in the pit were adolescents - both male and female The finds included the skull of a 7-10 year old child with craniosynostosis (premature fusion of one or more sutures of the skull) • Likely caused massive developmental issues • Would have required full time care = compassion H. Heidelbergensis in Europe Dali Skull (above) Jinniushan () • Transitional mixture of H. erectus and H. sapiens traits • 270-200 kya The last common ancestor between Modern Homo sapiens sapiens (us) and Neanderthals (a specialized European type of archaic H. sapiens) • Likely originated in Africa at least 600,000 ya. • Spread out and differentiated into local populations (genetic drift) Classification Issues Some researchers see H. heidelbergensis as a European species only, and call African archaics H. rhodesiensis In this view, H. heidelbergensis gave rise to the Neanderthals and H. rhodesiensis gave rise to modern H. sapiens. New Tool Technology The LEVALLOIS or "prepared core" technique • Standardization and efficiency • Not using any old flake • Core was pre-shaped so 6-8 similar sized and shaped flakes could be removed • Very standardized flake tools (points, scrapers, drills, etc.) • Hafted onto wooden or bone shafts Advantages: Faster Creation Process Sharper Tools More standardized Tools Possible Conserve raw material • More cutting edge per pound of raw material Wooden Tools Schoningen Site, Germany • 8 Preserved Spears • Dating: ~400,000 ya • Size and balance suggests throwing spears Lake Side Hunting Site • Hiding in Reeds, Throwing spear at Wild Horses • 20 Horse Remains ID'd • Wood was preserved in the anaerobic mud • Exposed by local mining activities Shelter TERRA AMATA, France • 400 kya • 21 Oval Structures - 25'-50' Long • Sapling posts with stone supports and central beams • Central Hearths in each structure - full control of fire

3 Big Events Made Africa the center of Research on Human Origins

1. 1925 Raymond Dart discovers "The Taung Child" in South Africa 2. 1959 After years of being regarded as crackpots, Louis and Mary Leakey's discover Zinjanthropus (Paranthropus boisei) at Olduvai Gorge, Tanzania 3. 1973 Donald Johanson finds "Lucy" (Australopithecus afarensis) in the Hadar region of Ethiopia

H. Erectus Migration

1.8myaHomoerectus appears almost simultaneously in Africa and West & East Asia • Evidence suggests that the early Homo erectus populations were quickly on the move out of East Africa only 100k or 200k years after the initial appearance of the species Why Migrate? • One Theory = cooler climatic conditions led to an expansion of grass lands from Africa to Asia.... With the grasses went African game animals that H. erectus relied upon and followed • Not a mass migration but a gradual flow of small bands of hominins out of Africa over thousands of years May have initially followed African animals but the H. erectus quickly moved into different climatic and environmental zones • Required a degree of technology and culture to adapt to new variated habitats... EarlyDatesandalackofAcheuleantoolsfromsites in China, Java, Georgia has disrupted an old narrative that suggested H. erectus arose in Africa, developed Acheulian tools around 1.6mya and then conquered the world with new technology. • TheseearlyfarflungsitesshowthatH.erectus emerged in Africa and left well before the Acheulean tradition was originated - suggests a long period of migration with many waves

Eugene Dubois

1858-1940 Dutch doctor interested in human evolution and search for fossil human ancestors Posted to Indonesia as part of Dutch army Spent 3 year searching and got lucky in Java in 1891- finding two fossils close to each other - large skull cap and femur showed upright posture - skull cap showed largest brain- ~1000cc (modern ape ~400 and modern human ~1300) - Named PITHECANTHROPUS erectus (upright ape-man) - publication largely ignored, b/c did not fit preconceived notions of what our ancestors should like or where they should be found - locked away until 1920s Problems 1- Scientists believed that a large brain size was the defining characteristic of our ancestors and upright posture seemed less important 2- Ethnocentric ideas- Europeans believed themselves the most advanced, therefore origin must have happened in Europe

Piltdown

1912, England Hoax Fossil Skull found by Charles Dawson that fit preconceptions - near modern intelligence and European origins - fossil named Eoanthropus dawsoni "Dawson's dawn man" - modern looking cranium and ape-like jaw - fraudulent- modern humans skull with jaw of modern orangutan fitted - 1949 fluorine test (measures amount of fluorine that has leached from surrounding soil into bones - discovered that skull is of entirely different age from associated animal bones found in same matrix - skull and jaw of different ages

Paranthropus robustus

2.2-1.5mya • South Africa • Brain 520 cc Sexual Dimorphism Present: • Average Height: Males: 3.75 ft. & Females: 3.2 ft. • Average Weight: Males: 119 lbs. & Females 88lbs • Sagittal crest is larger in males Evidenceofisolatedtooluse? • Bonetoolslikelyusedtodig into termite mounds found at several South African sites. • Wasthistool-making, termite-mound-digging behavior something shared by all populations of this species, or was it a regional behavior? Subsistence Astudyin2011studiedthe carbon in the enamel of teeth from 22 Paranthropus specimens • ItfoundthatParanthropus subsisted almost entirely on grasses, not solely on tubers and nuts as had previously believed • Nomodernprimatesofany sort exists so heavily on grass

Paranthropus aethiopicus

2.7 - 2.5 MYA • Thought to be descended from A. afarensis • Very small brain ~410 cc • Most famous fossil is the "black skull" found near Lake Turkana, Kenya Veryrobustface • Hugemolars • MassiveSagittal crest • Adaptedtoavery coarse diet with huge chewing muscles • P.aethiopicusislikely the direct ancestor to two more paranthropus species: - P. Boisei (East Africa) - P. Robustus (South Africa)

Australopithecus africanus

3-2mya South Africa Raymond Dart with Taung Child the first Australopith ever discovered in 1924 • Taung Child was a 4 year old A. africanus • Skull showed a flatter face and smaller teeth than a monkey or ape • Foramen magnum directly under the skull indicates bipedalism Cranial capacity around 440 cc • Sexually dimorphic - males 5' - females 4' females 60% of male weight Body and brain like A. afarensis • Less prognathus face (flatter face) • No sagittal crest • No diastema - Slightly longer arms than A. afarensis • Curved fingers • Suggests continued arboreal importance • Is a "Gracile" australopith - Compared to other australopiths, A. africanus had a very slight build • Very different than the robust australopiths seen in genus Paranthropus Diet mostly mixed vegetables • Possibly some meat - scavenging? - some hunting? Morehumanlikecranium-lessrobustthanits peers - slightly larger brain • VerylikelyadescendantofA.aferensis • AlsolikelyonthepathtotheHomogenus • Manyalsobetheancestorofanewfind Australopithecus sediba

Fossil and Behavior Evidence of A.M.H.s

300kya ThefirstevidenceformodernhumansappearsinAfrica Theevidenceisbothskeletalandbehavioral Evidence for behavioral modernity appears first but we are finding more older skeletons with modern characteristics The earliest forms appear to be transitional between Archaic and Modern Homo sapiens They are found in Eastern and Southern Africa They have many modern features but still have brow ridges, low skull, big face Theearliestfossilswithmodern traits date to 195 - 160 kya Ethiopia Smallface High, rounded skull Largebrowridges Herto Skulls Also in Ethiopia 160-154 kya Very large skull Long cranial vault 1450 cc Heavy bone Arching brow ridges NO mid facial projection Comparison of H. Heidelbergensis - Broad face • Low forehead • No chin to H sapien (Herto) - Much narrower face High forehead Chin Retains large brow ridge but not as massive Klasies River Mouth Klasies River Mouth, South Africa Two layers: 125 Kya; 70 Kya By 70 Kya there are modern human remains and evidence of modern behavior with new technology Border Cave SouthAfrica Dating is very uncertain some put the date at 90-100 kya ClearlymodernH.sapiens Europe Moderns by 36,000 ya in Germany & 27,000 ya in France (Cro- Magnon) Neanderthals as late as 30,000 - unlikely ancestral to moderns and overlaps with moderns No evidence of transitional forms! First AMHs - taller, linear, slender build (tropical characteristics!) Europe does not appear to site of modern evolution (supports replacement and contradicts multi-regional model) East Asia East Asia - some support for MRE Model See some continuity in local traits between H. erectus and AMH populations Early dates for clear AMH around 100 kya in China Problem - poor dating complicates early evidence Some late dates for H. erectus in Indonesia @ 50-30K = challenges MRE model - suggesting moderns and erectus overlapped China Jinniushan Proposed as modern 200 kya+ Casts doubts on replacement model Australia Arrival by 50 kya Earliest fossils from Lake Mungo 30- 25 kya Kow Swamp 14-9 kya DNA evidence indicates Australia was populated by modern humans in one migration around 50 kya Fossil Record BEST supports Replacement Model and Africa as source of AMHs - Africa- earliest fossils and transitional forms - No overlap with archaic forms in Africa (as in Mideast and Europe who co-inhabited with Neanderthals) - Earliest AMHs in Europe appear tropical - COntinuity suggested from East Asia not convincing, and earliest AMHs dates only to 100 kya (or more recently)

Australopithecus anamensis

4.2-3.8mya, Found in Kenya Fossilized Remains of several individuals recovered at sites in Kenya around Lake Turkana - Leg & Toe Bones - Jaw Bones - Canine Teeth • Environment would have been forests and woodlands that grew up around nearby lakes Ape traits: • Parallel molars • Diastema & Large Canine • Longer Forearms Human traits: • Canine teeth vertical not angled like typical ape canines • Heavy tooth enamel Strong jaws combined with heavily enameled teeth suggest A. anamensis ate hard, abrasive foods. • Likely were plant-eaters in general, relying on both fruits and tough foods such as nuts. Leg bones and big toe suggest strong bipedalism • Forearm length and wrists suggest this species was an adept climber as well A. anamensis (4.2-3.8 mya) appears to be a direct (or very close) ancestor of a second species Australopith classified as Australopithecus Afarensis

The Upper Paleolithic

50k-10kYA Knownas"TheGreatLeap Forward" or "Creative Explosion" Huge changes in human behavior and culture Allowed Humans to Outcompete Pre-Modern Populations throughout the world 6 major cultural changes NewToolTypes Broadersubsistencebase Larger,moresedentarysettlements Integrationofdistantanddiversegroups Elaborateburials Artworks New Tool Types - blades - SOULTREAN Tools- very fine bifaced tools - composite tools- made from more than one piece - spears, atlatl, bone harpoons- increasing distance makes for more effective hunting - bows and arrows The earliest actual bow was found in Germany and dates to around 10,000 ya A reduction in the size of projectile points is thought to signal the use of bows Small projectile points are found in Africa around 60,000 ya. Larger, more sedentary settlements Not many trees on the tundra Large animal bones solve the problem Bones from natural accumulations (can tell by weathering) as well as kills Mammoth Bone HOuses in Europe 18kya, 70 Houses and 30 sites Integration of distant and diverse groups Distinct Ethnicity Differences in culture are developing between groups of people Before 50kya great similarities across time and space, Upper Paleolithic has many more distinct styles of tools, art forms, housing e Long distance trade- evidence of materials far from sources like flint, obsidian Artworks - cave paintings, bone/ivory carvings, Venus figurines - date to 30kya and later -LASCAUX CAVE, France- initially thought to be a hoax Paint- bound with grease, marrow or blood Neto-tic Phenomenon- altered states of consciousness Rituals- footprints of teenagers found deep in cave

Primate Events in Each Epoch of Cenozoic Era

65.6 Paleocene- First primate-like mammal: Plesiadapiformes 55.8 Eocene- First Prosimian-like primates 33.9 Oligocene- Age of Monkeys, Fayum Desert 23.0 Miocene- Age of Apes: Proconsul, Sivapithecus, Dryopithecus - Some very early forms of possible hominins appear at very end of Miocene - Late Miocene Pre-Australopiths 5.30 Pliocene- Earliest true hominins 2.60 Pleistocene- Earliest members of genus Homo Not all hominin forms led directly to Homo There were likely multiple genera and species that were evolutionary dead ends Family tree was more like a branching bush

Homo Erectus in Dmanisi, Georgia

A very early form of H. erectus with primitive tools • Dated: 1.8-1.75 mya • Brain Size 775 to 650 cc • Small Stature Pre-acheulian technology found Good evidence of hunting and meat consumption - but no African game animals are present • Dmanisi inhabitants were living off local herbivores and dealing with mega-predators such as sabretooth cats and giant leopards. Extreme Lumping: 2013 analysis of 5 five Homo erectus skulls found in Dmanisi suggest strong similarities to H. habilis • Authors of the study make the argument that all early homo species (rudolphensis and habilis) and all homo erectus subspecies (no matter where they are located) are part of a single species. • This view is not widely held - the Dmanisi fossils are most likely an archaic H. erectus population that exhibited many ancestral features The amount of variability within these five skulls - suggests a high degree of physical variation within the whole H. erectus species from an early point onward

The Pleistocene

AKA "The Ice Age" • 2.5mya-12kya • Characterized by a series of glacial advances and retreats with massive glaciers covering the Northern Hemisphere • Increase in environmental variability producing complex & varied habitats • Different adaptations among hominin populations to these new environments Anewmemberofthe Homo genus emerges around 1.9/1.8 Mya - collectively known as Homo erectus • Isthefirstaccepted human ancestor to leave Africa and populated Asia and Europe

Electron Spin Resonance "ESR"

Absolute Dating technique • Measures the cumulative damage done by radioactive decay of minerals • Usually done on teeth • Human teeth are small, so the tests are usually done on animals with big teeth that are associated with them • Can be used on specimens that are several thousand years old up to millions of years.

Later Australopiths

After around 3 mya, Australopiths begin to significantly diversify • More derived characteristics (less ancestral features) as new species adapt to particular environments in Africa

Trends in Human Lineage/Distinguishing Human Features

As humans diverged from other ancient primates they underwent a series of anatomical changes • These changes help us to decide which of the fossil primates we find are on the line toward our own species Big Brains, Reduced Sexual Dimorphism, Thick Tooth Enamel, Reduced Premolar Honing, Bipedal Walking (only feature that absolutely signifies hominid) Big Brains - Humans have extremely large brains (1350 cubic centimeters) compared to other primates (Gorilla- 500cc, Orangutan and Chimp 400cc) - BUT human brains didn't start to significantly enlarge until around 2 million years ago, very late in evolution - Therefore, this cannot be used as a criterion for distinguishing early human ancestors from primate ancestors Reduced Sexual Dimorphism - Some ape species have about the same degree of dimorphism as humans (Chimps and Bonobos) - Human ancestors appear to have been VERY dimorphic until relatively late in human evolution, meaning sexual dimorphism cannot be used to distinguish human ancestors from other primate ancestors in fossil record Thick Tooth Enamel - Humans have thick TE, and apes tend to have thick TE as well - BUT- thick TE was rather widespread among Miocene Apes, therefore not a good way to distinguish fossil ancestors Reduced Premolar Honing - Most living apes have sectorial premolars that sharpen their canines when they close their jaws • They also have diastemas between their teeth to accommodate large canine teeth • Some fossil apes have reduced degrees of premolar honing • This is not a great way to distinguish early human ancestors in the fossil record BIPEDAL WALKING - Unique to hominins • Appears early • Is a true defining characteristic that distinguishes hominins from other primate ancestors

Australopiths (Genus: Australopithecus)

Best known, most widely distributed and most diverse of the early African hominins • 4.2-1.2mya - the longest enduring hominins yet known General Features of the Australopiths: • Bipedal • Brain slightly larger than chimps • Reduction in size of front teeth • Increase in size of molars & enamel thickness How do they fit in the Evolution of Humans? • Some ancestral to genus Homo • Relationships to each other not completely clear Australo = Southern • Pithecus = Ape • Australopithecus = southern ape • The name was coined by Raymond Dart who discovered the Tuang Child Mainly found in East and South Africa • Some specimens found in Chad but we don't understand the relationships yet 4 major species: A. anamensis A. afarensis A. africanus A. sideba

H. Erectus in China

Dragon Bone Slope (Longgupo) • FoundAnimalbones,Primitive Tools, a fragment of a erectus mandible and teeth • InitiallyDatedto1.96-1.78mya- very controversial early date - Would be the earliest H. erectus date anywhere • NewDatingsuggest1.8-1.4mya Zhoukoudian (near Beijing) • Translates to "Dragon Bone Cave"Best known H. erectus site in China • Muchworkdonein1920s at least 40 individuals recovered • BoneslostduringWWII when trying to send them to America • Luckilyexcellentcastsmade "Dragon bones" are fossilized bones (Dinosaurs, Mammals, Hominins) • They have been sought after in Chinese culture for centuries to use in traditional medicines and as aphrodisiacs • Boiled in Soups or Ground Up Zhoukoudian Remains Short,stockyindividuals • Brainlessthan1000cc • Occupied800,000- 400,000 ya • Lotsofanimalbonesandstone tools from a very long occupation • Mostlikelycarnivoresbrought kills into the cave, H. erectus scavenges them.. • Evidence=cutmarksoverlying carnivore marks & cut marks not on the choicest pieces

H. Erectus Technology

Earliest H. Erectus Technology • DevelopedorAdopted Oldowan Toolkit - Classic Core tools and Flake Tools • Slightlymorecomplexityand variety than the tools used by earlier Homo specie New Acheulian Technology developed by Homo erectus in Africa around 1.6 / 1.7 mya • Named for a site in France (Ste. Acheul) where the technology was first defined in the 19th century • Toolkit was expanded to include handaxes, cleavers and a wide range of flake tools Bifacial Flaking = Flaked on both faces to make the tool thinner and to shape it. • The "faces" are the two sides of the tool • The "edges" are where the sides come together to make a sharp cutting edge Soft Hammer Percussion - a secondary step where bone, antler or other softer material are used to finish the tool • Makes thinner, flatter flakes • Provides more control to make sharper tools Advantages over OLDOWAN: • Straighter edges • Thinnertoolswith Sharper edges • Standardized Tool Shape • SpecializedToolswith a wide array of functions Importance of handaxe: • Required effective communication skills to pass along ideas of form and design • Significant Forethought and Planning also Required - Find the right raw materials - Had to mentally conceptualize the finished tool before creating it and each step along the way

Early Hominins

Early hominins may have lived throughout Africa, but in East and South Africa we have both preservation and exposure Pre Australopiths: 6-4.4 mya Australopiths: 4.2-1.2 mya Early Homo: 2-1.4 mya

Blades

FLAKES THAT ARE TWICE AS LONG AS THEY ARE WIDE A more sophisticated form of prepared core technique Characteristic of Upper Paleolithic in Europe (post 30,000 ya) Found by 100 kya in Africa (possibly earlier) Another prepared core technique where the core is prepared so that long, thin flakes can be removed Blades are often removed with a punch which applies very precise pressure Very conservative of raw material Blades can be further retouched into other tools Klasies River Mouth South Africa - Blade tools by 100kya - Geometric microliths - Aslotismadeina wood or bone shaft. The microliths are inserted and secured with natural gums and resins The microliths were hafted into shafts to make composite tools (tools with more than one part) of various sorts Microliths did not appear in Europe until the Mesolithic- around 12 kya

Anatomically Modern Homo sapiens (A.M.H.s.)

Flat face Don't usually have heavy brow ridges Vertical forehead Pronounced chin Smaller, narrower face Two Main Models: Regional Continuity Model: Multiregional Evolution (MRE) H. sapiens evolved simultaneously in different regions of the world out of local H. erectus populations Replacement Models Modern Homo sapiens sapiens evolved only once and migrated out, replacing pre-modern populations throughout the world

South African Fossils

Good preservation linked to Limestone Geology of the region Limestone forms from the skeletal fragments of marine organisms - full of cracks and fissures, easily dissolved by rainwater - consequently limestone deposits are often filled with caves and tunnels - frequently filled with marine fossils - can also contain more recent fossils of organisms that fell into fissures and caves and became preserved as casts or molds, or became mineralized within the limestone Advantages: Limestone caves = preservation Limestone mining = exposure Sterkfontein Limestone Quarry Disadvantages - Limestone sediments cannot be dated with K/At - Often can only date finds by using sediments containing fossils of known age done via biostratigraphy - dates there approximate- aka relative dating

Homo Erectus in Java

Home of the first H. erectus fossils • 6 total sites have been discovered since 1891 all in East Java • Arrival by 1.8-1.6 Mya During the glaciations when sea levels dropped, many of the islands of southern Asia were joined by land • People and animals could move around freely on foot Interesting Fact - No stone tools positively associated with H. erectus sites in Java. • How were local populations butchering meat they had hunted or scavenged? During his 1891 excavations Dubois collected hundreds of mammal bone and shell samples found near the "Java Man" remains. • Modern analysis of these remains has given some important clues to the foods H. erectus relied upon in Java and the tools he used. • Shellswerenotjust evidence of food but also may have served as one of the primary tools of erectus in Java. • Cutmarksonassociated bones seems to have been caused by the use of shell knives

What is a Hominin?

Human ancestors Bipedal locomotion Large brain Toolmaking ability

H Erectus in Eurpe

InEurope,fewremainsof Homo erectus have been found, and those that have are controversial • Acheuleantoolsareknown from 500 kya onward • Recentlyadramaticfindof Acheulean Hand Axe from Spain dated to 900 kya Far more tools than remains Gran Dolina, Spain Oldest H. erectus or (H. antecessor) site in Europe • Remains of several individuals, • Occupied between 1.1 Mya - 800,000 ya • Secure Dating Discovered during the construction of a railway for the transport of minerals at the end of the nineteenth century • Fossils show some progressive features reminiscent of Modern Man • Tools are Improved Oldowan Chopping and Flake Tools only • Why No Acheulian Technology? Happisburgh, UK - United Kingdom • Dating 990,000 - 780,000 ya • Bifacial flaked stone tools • Great Britain was physically connected to mainland Europe • Occupied during a cold period - was there shelter and fire? Pakefield, UK Dating: 700,000 ya • Northern United Kingdom • Complex Flake tools - Likely part of the Acheulean tradition • No Fossil Remains

Significance of Evidence from Limbs and Extremities of Ardi

Itappearsthatapes developed their specialized forms of locomotion (knuckle walking, and very flexible feet for climbing) AFTER they split from the human line • Weareusedtothinkingofape traits as being primitive, but they appear to be as modern as the human traits that make us different from them It appears that bipedalism did not evolve in the savanna • Ardi was a semi biped in a forested environment • Some of the selective pressures thought to be associated with the emergence of bipedalism may not apply

Orrorin tugenensis

Late Miocene Pre-Australopith "Original man" in local language, found in Tugen Hills in Northwest Kenya 6.2-5.6mya dated by radiometric methods offering solid date - lower limb bones indicate strong bipedal locomotion - approx size of chimp and had small teeth with thick enamel, similar to modern humans

Genus: Ardipithecus

Late Miocene Pre-Australopith Ardipithecus kadabba - 5.8-5.2mya - Found in Ethiopia - Mandible, teeth, hand foot bones recovered - Probably similar in body and brain size to a modern chimpanzee • Had canines that resemble those in later hominins • Toe bones suggests bipedalism Ardipithecus ramidus 5.6-4.4 mya • Very late Miocene and Pliocene • Ethiopia • Skull fragments show foramen magnum located under skull = a degree of bipedalism - Many A.ramidus remains recovered from Aramis site in Ethiopia • Remains dated to4.4mya by K/Ar • One very fragmented but rather complete individual female known as "Ardi" was recovered there Ardi: Female, 4 feet tall, 100lbs, nearly 60% complete - Environment: Aramis site where Ardi was found is an environment that is currently very arid; Plant and animal fossils associated with Ardi indicate that the environment was wooded and moist back then - Teeth: Toothenamelsuggestsa diverse diet of fruit, nuts, leaves etc. • Bluntcanineslikemodern humans, not the fangs of modern chimpanzees • Littlesexualdimorphismin teeth • Suggestslessviolentmale competition for mates & possibly a high degree of cooperation among males and females Facial Profile: Ardihadaprojectinglowerfacebutmuch less so than chimps • Other aspects of the skull are quite different from chimps Pelvis: Analysisofpelvis and Lower Limbs suggests she was a tentative upright walker • Wouldhavebeen a poor runner • Veryableclimber and likely spent a bit of time in trees Hands/Upper Limbs: Ardi had relatively short palms and fingers and was not adapted for knuckle walking • She not have the specialized anatomy to allow her to swing and hang the way apes do • Her hands were more similar to those of earlier apes rather than modern ones Feet/:Lower Limbs: Strongglutsmuslceswould have enabled her to stand upright fairly efficiently • Feethaverigidtoesnotthe flexible feet of modern apes • Thebigtoedivergesasdo those of apes.

Sahelanthropus tchadensis

Late Miocene Pre-Australopith 5-7mya Blends apelike and human characteristics - Biostratigraphy from Kenya 1500 miles away from fossil find, so tentative dating Ape-Like - 320-380cc - Huge supraorbital torus (brow ridge) - Large muscle attachments on skull - elongated skull Hominin - small vertical face - small canine teeth with reduced honing Intermediate Features - position of the former magnum suggest bipedality Found well outside of East Africa, where most fossil hominids found, suggest human ancestors were widely distrusted, and suggest early development of bipedalism

The First Fires

Likely started by lightning strikes (i.e. Forest fires, grass fires etc.) • Flames were transferred from natural sources and kept alive with collected wood and grasses in protected locations.. • Maybe started sometime between 2.0 and 1.6 Mya • Starting fires without naturally occurring flames likely much later 400 Kya Advantages Does Fire Provide? Protection Light Warmth Cooking Survival in Cold Weather • Enables movement into cooler climates like Europe, Northern China Protection From large animals - Lions, Saber Tooth Tigers, and Bears (Oh my) • Protection from other hominins (who may not have had fire) Cooking Softens meat • Breaks down vegetable fibers • Makes starches edible • Kills parasites Extends the day beyond sunset (tool making & repairs at night, socialization over the fire) • Enables occupation of dark and damp caves Archaeology of Early Fire Unlikestonetools,Directevidenceofburning, such as ash and charcoal, is easily destroyed by wind and rain. And even when such remains are found, determining whether the fire was natural or human-made is VERY tricky. • Indirectevidence(burntartifacts,ecofacts)can offer some important clues but the best evidence would be true hearth features with heated stones and burnt materials in place... Evidence of Fire: Zhoukoudian Good evidence for fires not necessarily always in the same strata as evidence for humans • Evidence: "Ash" identified, then denied and later reconfirmed • Indirect Evidence: Burnt Bones and Stone tools in Same Levels dating to around 700 kya Evidence for Fire: Israel Site: Gesher Benot- Ya'aqov, Israel • Dating: 795,000 kya • The Evidence: Charred Wood & Seeds, Burnt Bones, and Heated Stones in isolated concentration that are interpreted as being near Hearths • Site was sadly destroyed before the likely hearth areas could be excavated Evidence for Fire: Wonderwerk Cave, S. Africa - Dating 1.0 Mya • Evidence: Ash of burnt grass, leaves, brush and bone fragments in a context 30 meters deep (associated with Acheulian Tools) • Ash had jagged edges, showing that they were not burned elsewhere and blown or washed into the cave, which would have worn such edges away. • Possible Cooking - Due to animal remains in ash Evidence in Kenya Koobi Fora - Kenya • 1.6mya • Red burnt stain in soil with phytoliths from many plants - photoliths- Silica structures in the cells of plants • Characteristic of species • Durable Phytoliths Found = Grasses, Tree Species (w. Palm Wood Dominating) • Varieties identified suggests that the plants were intentionally gathered to make a fire - This mix of Plants and Grasses Would Not have grown together - Selection favored Palm Wood - a wood that burns easily and brightly! Fire Conclusions: It is pretty certain that H. erectus used fire • WedonotknowifH. erectus knew how to make it (especially early on) - most likely was able to keep fire alive for long periods of time • Earliest Dates (Pre 1 Mya) the evidence is questionable but starting to become convincing • Fire was likely necessary for moving into colder climates when you have no body hair for warmth

Continuity and Change in H. Erectus

Lots of similarity across time and space for H. erectus cultures • Gradual slow increase in brain size over time • Tools: Increasing symmetry, variety and sophistication, but very similar to initial Acheulean tools developed in Africa 1.76 Mya Food—they are probably still largely scavenging , foraging and some regular hunting for game We still don't find many sites where they lived - so no real evidence of shelter (aside from caves) No burials or evidence of ritual ideas Around 800-400 kya - we a sudden & rapid change both physically and culturally

Ongoing Study of Human Origins

Many, many projects searching for human origins in Africa Multimillion dollar business w/ huge workforce, research grants, scientific and popular books/articles, traveling exhibits Lots of new information every year The fossil record is fragmentary and partial • Researchers find bits and pieces, widely distributed in time and space • Researchers announce their finds and give their best estimate of where they fit into the overall scheme • Each new discovery is an opportunity to reassess old ideas • Research therefore lurches forward in fits and starts

Why Meat?

Meat is high quality protein • Marrow and fat have lots of calories and minerals • It is easy to digest • A little goes a long way • It would have been a preferred food source to hominids Impact of meat-based diet: May have reduced the need for huge dentition • May have also reduced the amount of time early hominins had to spend finding food and eating it

Replacement Models

Modern Homo sapiens sapiens evolved only once and migrated out, replacing pre-modern populations throughout the world Requirements: There must be anatomical differences between modern and premodern humans that clearly distinguish modern H. sapiens as a separate species Theremustbegeneticdistinctionssufficienttoindicateseparate species Ifmodernsaredistinctfrompremoderns,transitionalspecimens should occur only where moderns evolved There should be evidence of moderns and premoderns coexisting in the same regions once moderns spread out With Replacement Models There should be complete separation between modern and premodern H. sapiens except where modern H.sapiens developed Differs from MRE Model: Where there should be fossil and genetic continuity (evidence of transitional forms that share characteristics between moderns and premoderns in many parts of the world) 2 Replacement Models Complete Replacement AMH emerged 200,000 years ago in Africa, then migrated and replaced populations in Europe and Asia They were a separate species and could not have interbred with local populations Partial Replacement AMH were physically able to interbreed with local populations At least some interbreeding took place

Genetic Evidence of AMHs

Modern Humans show little genetic variation - much less than apes Recent single origin of amHs) Nuclear DNA - 2 clusters of variation: sub- Saharan Africans and everyone else Suggests origin of AMHs in Africa (longer time for variations to accumulate there) All groups (i.e., of our species) are very similar African women are the most diverse - expected in the oldest population = longest time for mutations to occur Samples from the rest of the world appear to have branched later - have less variation Molecular Clock suggests origin of AMH @ 200K

Multiregional Evolution (MRE)

Multiregional Evolution (MRE): For H. sapiens to have evolved concurrently in different regions from local H. erectus populations there are several requirements There must have been sufficient species mobility to insure gene flow: Modern humans can all interbreed with each other, which means they are all the same species. There would have had to be constant contact among H. erectus populations so that they did not become separate species over a period of 1 million years (+/-) MRE Taxonomy According to the MRE Model: All species after H.erectus are considered to be H. sapiens with the different forms (eg: neanderthalensis, heidelbergensis) classified as subspecies (not unique species) This is the only way to explain how we could have remained a single species across time and space Some argue: Variation within the fossil record does not warrant division into separate species All features that distinguish H. erectus from the australopiths also characterize modern H. sapiens Required Fossil Implications of MRE Model There must be evidence that H. sapiens emerged in many parts of the world, not just in Africa We should see transitional fossil forms being widespread in each region leading to a.m. H.s. We should see parallel changes in each region (Europe, Africa, and Asia) occurring more or less simultaneously There must be no set of "modern" traits that are missing among all premodern populations Required Genetic Implications of MRE Model We would expect that since human populations had such long-term in place evolution, substantial genetic variation should be present between each of the regions We should also expect the same amount of genetic diversity within each regional population

H. Erectus Hunting

Olorgesailie, Kenya • 900,000-700,000ya • 60baboons • Large unmodified stones likely for throwing • Lots of Acheulean tools likely for butchering Organized hunting of Baboons • Cooperation, coordination, communication Spain Sites (Torralba and Ambrona) • 400,000ya • Animal bones in swamp • Acheulean Tools • Tool marks on bones Possibly H. erectus drove the animals into the swamp and killed them • Again Suggests group hunting, cooperation, skill Hunting Evidence is inconclusive • Most bone too weathered to detect tool marks • Lots of animals remains but few tools? What does this suggest? • Possibly animals died in swamp and occasionally H.erectus butchered them

Early Homo

Post Cranial skeleton similar to Australopithecus • Brain 20%+ bigger 600-700 cc • Reduced jaw • Smaller teeth but relatively parallel molars There are several varieties of early Homo, but their relationships are not well understood, so collectively they are known as Early Homo • 2 Major Early Homo Species: Homo habalis and Homo rudolfensis Early Tools Suggests a fundamental change for these species • Larger brain = larger capacity for culture • Stone Tools = material evidence for problem solving

Homo sapiens Migrations

Recap: H. sapiens sapiens emerges in Africa around 200 kya • Leaves Africa by 135 kya • In SW Asia by 100 kya (Skhul, Qafzeh) • Reaches Europe 40 kya • Neanderthals gone 30 kya What else was happening? Glacial Maximum • Sunda and Sahul shelves exposed • Islands joined or closer together - lot of open water b/w Asia and Australia - boat built with stone tools and sailed across Timor sea Earliest Americans Last Glaciation 70-12 kya Most convincing evidence for humans in Americas post dates 20 kya Some earlier sites, but controversial Beringia (glacier) • Glacier advance = sea level drop • Last glaciation = 120 meters below modern sea levels • Continental shelves expose Two Routes into the Americas - Ice free corridor as glaciers retreat around that opened up around 12kya - Coast ROute along exposed continental shelf, under water now so no evidence Clovis - named for type site in New Mexico - classic fluted point stile - Paleoindians were makers of Clovis points, date 11,500 Mobile big game hunters- hafted paleoindian points Also ate smaller animals, nuts, etc. Pre-Clovis- all controversial Criteria: Best evidence is human skeleton that can be directly dated using radiometric techniques Next best evidenced is 3 criteria: 1. Artifacts clearly made by humans 2. Verifiable context 3. Credible dates • Minimum age of the site must be demonstrated by primary associations of material suitable for reliable isotopic dating. ie: radiocarbon dating

The Death of the "Missing Link"

Remember:WeDidNotEvolveFromChimpanzees-Weshareda common ancestor from which we both split • Chimps(andallapes)andhumanshavebeenevolvingindifferent directions ever since • Wejustdidnotknowthat chimp (and other ape traits) are modern adaptations and not primitive traits that humans evolved away from

Premodern Homo sapiens

Sometimes called "Archaic" Homo sapiens or "Transitionals" Not much known about this time period, but gradually being filled in with new research Overlapping end of H erectus to beginning of modern H sapiens Fossils • Have features of both H. erectus and H. sapiens • Larger brain than H. erectus • Smaller features than H. erectus but larger than modern H. sapiens 3 Main Species: Homo heidelbergensis: - Primarily includes European, African and some Asian fossils Homo neanderthalensis - Refers to a specialized form of Premodern H. sapiens found only in Europe and SW Asia Homo denisova - More closely related to Neanderthals, found in Siberia and SE Asia Situated in the PLEISTOCENE- Pre-Modern Dating Issues - Date Range - 800-125 kya • Too young for Potassium Argon and too old for Carbon 14 • Requires different sets of dating tools: Uranium Series, Electron Spin Resonance, etc. • Problematic techniques with pretty large error factors possible

Australopithecus sediba

SouthAfrica • Found2008 • 2mya • Brain420-460cc • Chimpsized,longarms • Muchmorehuman brain, face, teeth, pelvis and legs and hands • GracileAustralopithecus • Possibleancestorto modern humans Sedibawasfoundin Malapa nature reserve by a nine year old boy • Heisthesonof paleoanthropologist Lee Berger • Theboywasexploring the area surrounding his dad's excavation site -fell in death trap to be trapped in limestone deposits Not yet clear how A. sediba fits into the evolutionary tree • Likely a descendant of A. africanus • Could be directly on the path to the early Homo species or could be another side branch.

Paleomagnetism Dating

The earth's magnetic field has varied in orientation and intensity through time • Magnetic minerals line up with the earth's polarity when they are being formed • A date can be derived by measuring the orientation of magnetic minerals in rocks and sediments The earth periodically reverses polarity so that south becomes north and vice versa • The last full reversal was 780,000 years ago • It is a handy marker for geological dating

Genus Paranthropus

These are "Robust" Australopithecines • Bodies like other Australopithecines • Brain slightly larger, but within normal range • Massively robust skulls with lots of bone Skulls: Sagittal crest • Very wide, flaring cheekbones • Huge jaws and molars The three species of this genus likely do not relate to the human lineage they are separate branch of the hominin tree • May have lived alongside later Australopithecus species and early Homo species in Africa before going extinct Paranthropus species were highly specialized to their particular environment • Made them very successful but also was their undoing when they unable to adapt to environmental change • Not a failure - survived for 1.5 million years - Modern Homo sapiens only ~200,000 years so far

Quadrupedal Humans

Turkish family habitually walks quadrupedally Sensational journalism suggesting family members were evidence of pre-bipedal humans They have an anomaly in their brains that affects coordination and balance so they are incapable of regular bipedal movement

Why Did Hominins Become Bipedal? Advantages/Disadvantages of Bipedalism

We don't really know, but anthropologists seek the answers in the adaptive advantages of bipedalism None are so clear cut that they explain why bipedalism was selected for, but they have been sufficient to overcome the disadvantages Advantages: 1. Carrying While Walking - bipedal individuals can carry things more efficiently- carrying children while looking for food, carrying sticks and rocks to throw, bringing food found in the open back to a safe place to eat, running away while eating (possibly necessary if you are a scavenger) 2. Taller - enables humans to see over tall grass in savanna but, other animals just climb tress, stand temporarily, or fly 3. Longer Reach - makes it easier to gather fruits in high tress and bushes, but bats, giraffes, quadrupeds all seem to get fruit just fine- costly solution to non problem 4. Endurance - definite advantage of bipedalism - we can walk/run for a very long time without becoming exhausted b/c bipeds use much less energy while walking- adaptive for long walks in search of food in patchy environments - BUT- the earliest hominids may not have been fully upright, therefor walking bipedal would have cost them more energy- camel exception 5. Heat Dissipation - vertical position cools the body by: presenting smaller surface to sun when overhead, gives more of body access to cooling breezes, gets face and head away from hot ground - loss of hair and development of sweat glands suggest thermoregulation to be important aspect of human evolution Disadvantages: 1. Easily seen by predators, tho lots of quadrupeds have same problem 2. Exposes soft underbelly, making humans susceptible to frontal assaults 3. Run slower 4. Reduced agility- can't change direction quickly, have to slow down or make wide turn, many other animals can switch directions without significantly slowing down 5. Lower Back Problems - upright posture puts a lot of pressure on lower back, takes entire weight of head and torso 6. Hernias- protrusion of an organ or piece of intestine through a weakness in abdominal wall, gravity causes guts of bipeds to slump downward putting pressure on abdominal wall 7. Leg Injuries are Incapacitating- before prostheses, leg injuries would have been disastrous, quadrupeds can live on 3 legs 8. Instability- frequent tripping, slipping, falling

Stone Tools

While some new evidence suggests that some Australopiths made or used stone tools.... • It is only after the rise of Genus Homo that hominins start to rely on tools and culture to a great extent OLDOWAN TOOLS Found at Olduvai Gorge • Associated with Homo habilis • Pebbles with flakes struck off to make a sharp edge • 1.8mya Oldowan core tools and flake tools Flake tools are when a flake is removed from a core, and the flake is used as a tool Hominids selected good rocks and brought them to the site • Suggests planning and a good understanding of the properties of stone Advantages Hominin teeth and nails are not strong enough to tear through tough animal skin, break open bones etc. Tools likely expanded variety of foods available to these species • Weapons help chase away predators

Genus Homo

around 2.5 MYA • When the first member of genus Homo emerged, there were at least 3 types of hominins living on the planet: - Paranthropus robustus (South Africa) - Paranthropus boisei (East Africa) - Australopithecus sediba (South Africa Genus Homo appears at the beginning of the Pleistocene (2.6mya- ice age) • Most of human evolution takes place during this epoch

Paranthropus boisei

• "Hyperrobust" • 2.6-1mya • Brain ~515 cc • East Africa Very wide and dish-shaped face to allow for massive jaw muscle along the cheeks • Molars were four times the size of a modern human's. • Thickest dental enamel of any known early human Noticeably Sexually Dimorphic First P. Boisei: Found by the Leakey's Working in East Africa at Olduvai Gorge, Tanzania • Found P. boisei in 1950s after years of work • Son Richard and his wife Maeve continue the work P.Boiseiisthoughttohavelivedinenvironments that were dominated by grasslands but also included more closed, wet habitats associated with rivers and lakes.

Compassion and Cannibalism

• This skull from Dmanisi is of a very old, toothless man • The fact that he lived to be this old, and was incapable of chewing hard food indicates that people took care of him • This suggests that H. erectus had developed a degree of compassion At Zhoukoudian several of the skulls were broken at their bases, suggesting that Homo erectus may have intentionally broken them open to eat the brains.... Many of the H. erectus skulls from Zhoukoudian were also missing their faces and some had puncture marks in their brow ridges • One piece of human bone was etched with stomach acid, indicating that it had been in something's stomach. Something much bigger than a human! Themostrecent interpretation is that the H. erectus at Zhoukoudian were victims of the giant Pleistocene Hyenas that brought their kills back to the cave. • Thebrokenskullbaseswere where the hyenas had broken open the skull to get to the brain - not cannibalism Gran Dolina, Spain • Dated:1.1Mya-800kya • Humanbonesmixedwith animal bones • Allhadbeentreatedthe same: cut marks, intentional breakage, percussion marks and chop marks • Concludedthattheanimal and human remains were the result of "consumptive activities". Cutmarksfoundon the face indicate skinning and de- fleshing activities. • Cranialfragments also display abundant evidence of breakage • 9out11individuals were young not adults • Notasingleincident - over hundreds of years (at least) Why Cannibalism at Gran Dolina? No Clear Answers.... • NeedforFoodduringperiodsofHardship? - Not Based on Evidence from Extensive Mammal Remains Recovered • RitualisticBehavior? - No evidence for this level of social culture yet with H. erectus • Territorial Defense? - Defend and mark territory by killing (and eating) the weakest invaders


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