3 There is no straight line in the greater than four million-year-old journey of the family called HOMINIDAE.
4 From Ape to Hominid Proto-Hominids (Opportunistic bipeds) Sahelanthropus tchandensis / Orrorin tugeninsisTransitional Opportunistic-into-Habitual BipedsArdipithecus ramidus / Australopithecus anamensisFirst True Habitual Upright BipedsAustralopithecus afarensis / A. africanus / A. garhiAustralopithecus robustus / A. boisei
5 Identifying the first hominids In L.C.A., look for anatomical features shared by humans and living great apesStarting from there, 1st hominids must have evolved at least one feature that we see only in modern humansScientists focus onAnatomy related to bipedalismLarge brain size, hard evidence for culture, language, etc., come much later.
6 Evidence of Bipedalism Placement of foramen magnumShape of spineShape of pelvic girdleBicondylar angle (knock-kneed)Parallel toes (no divergent big toe)Two fixed arches in footSide to side / front to back
7 Or WHY WE WALK ON TWO LEGS ORIGINS OF BIPEDALISMOrWHY WE WALK ON TWO LEGSDownload and read these articles:The Origins of Habitual Upright BipedalismThe Origins of Obligate Bipedalism in HomininsThe Whats and Whys of Habitual Upright Bipedalism
8 If you asked a roomful of anthropologists why we walk on two legs - not get the same answer from any two of them. Specialists cite everything from changing landscapes to needing to keep cool to heightening sexual attraction - generally agreeing only on one point: that everyone else's hypothesis is wrong. Let’s take a look at some of these hypotheses.
9 Six Major Hypotheses Grabbing A Bite Hauling Food A New World Keeping CoolAttracting MatesWeapons and ToolsALL these models may have played a role in the emergence ofhabitual upright bipedalism
10 From Ape to Hominid Proto-Hominids (Opportunistic bipeds) Sahelanthropus techandensis / Orrorin tugeninsisTransitional Opportunistic-into-Habitual BipedsArdipithecus ramidus / Australopithecus anamensisFirst True Habitual BipedsAustralopithecus afarensis / A. africanus / A. garhiAustralopithecus robustus / A. boisei
11 Proto-Hominids Molecular biology strongly suggests: Last common ancestor of chimps & humans lived 5-8 m.y.a.Two recent finds warrant our attention:Sahelanthropus tchadensisOrrorin tugenensis
12 Sahelanthropus tchadensis 6 - 7 m.y.a.Brain size: 1/4th of oursNo post-cranial bonesDon’t know if habitual bipedLived in variety of habitatsLikely ate mainly fruit, with smaller amounts of other foods.Download and read:The Earliest Possible Hominids
13 Orrorin tugenensis 6 m.y.a. Remains fragmentary Canines / premolars extremely ape-like BUT with thick tooth enamel (like hominids)Maybe bipedalInferior side of femoral neck (#1 on picture) is thick (like hominids)
14 Ardipithecus ramidus Transitional Opportunistic-into-Habitual Biped m.y.a.Possibly bipedal (but not like us)Small bodied ( lbs); small brained ( cc)Combo of hominid-like & chimp-like traitsDiet: unknown (relatively thin tooth enamel)Well-watered, forested environmentDiscovery Channel Website About "Ardi"
15 Australopithecus anamensis m.y.a.Fragmentary remainsTeeth and jaws similar to fossil apesMay be earliest incontrovertible evidence of bipedalismStrongly resembles Austr. afarensisStreamside forests
16 Australopithecus afarensis Small-brained, bipedal human ancestors. The benchmark by which anatomy of all other early hominids is interpreted.4 - 3 myaEast AfricaFully bipedalMix of human-like & ape-like traitsForests, open woodlandsSexually dimorphic
17 Lucy: 1st afarensis found Her discovery revolutionized ways of thinking about early hominids. Hadar, EthiopiaAbout 3’8” tall; 55 lbsLong arms / short legsMid-20s when diedTeeth: small & unspecialized, indicating a mixed, omnivorous diet of mostly soft foods (fruits)Left to right: Lucy’s bones, reconstructed Lucy, modern human
18 A. afarensis skull morphology MaleFemale (Lucy)Cranial capacity: cc (2/3rds - 1 water bottleSmall sagittal crest in malesSlightly projecting upper canine teeth in malesParallel rows of cheek teeth (like apes)
19 afarensis body morphology Ground or tree-dweller? Slightly curved hand & foot bonesRelatively long and powerful armsBowl-shaped pelvisKnock-kneed (knee joint angled inward)Heel bone heavily built (like ours)Foot may have had high, fixed arches (Laetoli?)
20 A. afarensis footprints Laetoli, Tanzania: home to a footprint trail 3.5 m.y. oldProbably a trackway of A. afarensis
21 Selam: 3 yr old baby girl Au. afarensis Ethiopia (Hadar)Lived 3.3 m.y.agoApe-like scapulaHuman-like kneesFinger bones partially curvedHeel bone well-developedEndocast shows delayed brain growth (like us)Chimp-like hyoid bone
22 Australopithecus africanus m.y.a.Mainly S. AfricaMixture of habitatsFruit, salads, insects, small easily captured preyBrain size: 1/3rd oursRelationship to other hominids? UnknownThis species slightly different from A. afarensis: slightly taller, less facial prognathism, slightly larger brain. Also lived in drier habitats (especially dry scrublands and perhaps open grasslands), and thus may have exploited different resources.
23 Australopithecine Foraging Behavior Foraging (the systematic search for food and other provisions) was THE lifeway of all hominids from the earliest australopithecines until about 10,000 years ago (the start of agricultural modes of subsistence.Foraging by australopithecines and early species of Homo most likely consisted of collecting roots, berries, seeds, nuts, salad greens, insects, etc. Around 2 m.y.a meat, obtained by scavenging, became part of the foraging way of life. Eventually fish and shellfish would be added.
24 The Robust Australopithecines Dietary specialists? One of most fascinating branches of human family treeReveal radically different way of being hominidAbout 2.5 m.y.a they diverged from our own lineage - existed down to about 1 m.y.a.Came to be defined by an adaptation to eating hard foods like nuts, seeds, and roots
25 Robust Austraopithecine Morphology m.y.a.South and East Africa3 species - united by suite of features related to eating tough foods:Extremely large molars / premolarsDished faceExtremely large chewing musclesWide-flaring cheekbonesPronounced pinching-in behind the eye orbitsProminent sagittal crest
26 Robust australopithecine behavior Digging sticks used by modern chimpanzees. While such tools have not been found with robust australopithecine fossils, it is possible they used such toolsOmnivores, but relied on hard to chew foods (nuts, roots, seeds)Probably used tools (bones/horns showing polishing, maybe used for digging up roots)Lived in (open) woodlands and savannasEvolutionary dead end
27 Major adaptive shifts in hominid evolution ca. 2 m.y.a. Australopithecine lineageGracile lines become extinctRobust lines see an intensification of adaptation to hard object feedingEmergence of Homo lineageSeveral new species appear on African landscapePhysically / behaviorally different from earlier & contemporary australopithecinesFlatter facesBrain reorganized (lateralization & language regions)Unquestioned manufacture/use of stone tools (bone/horn/wood?)Added meat to diet (scavenging)Some species have brains as large as 750 cc
28 Earliest Homo speciesContentiousness regarding who belongs to early HomoAt least 3 (perhaps more) Homo speciesHomo habilis = m.y.aHomo rudolfensis = m.y.aHomo erectus (aka H. ergaster) = m.y.a.
29 Early Homo Behavior Stone tools 1st appear ca. 2.5 mya Most often attributed to H. habilis ( maybe A. garhi)Earliest tools (Oldowan tradition)Flakes (cutting/scraping)Chopper / chopping tools (“smashers / bashers”)HammerstonesSome bone/horn w/scratches (digging?)Meat eating takes on increasing importance after 2.5 m.y.a.Several types of sites: quarries, food processing locations
30 Making / Using Oldowan Tools Hominids often traveled up to 10 km to acquire right kind of stone from which to make tools.
31 Early Homo Scavenging Behavior An early hominid, Homo ergaster, depicted in this diorama from the American Museum of Natural History's Hall of Human Biology and Evolution, lived nearly 2 million years ago in the eastern Rift Valley of Africa.Can a hominid eat meat obtained like this and not get sick? Perhaps if one gets there within a few hours of a predator’s kill.
32 Homo erectus Out of Africa Earliest in Africa = 1.8 (H. ergaster)Island SE Asia = 1.7 m.y.a.Continental Asia = 1.4 m.y.aRep. of Georgia = 1.7 m.y.a. (H. georgicus?)Spain = 800,000 y.a. (H. antecessor?)Flores = 90,000 y.a. (H. floresiensis?)
33 Homo erectus (Prometheus Unbound) First hominids to make tools to a predetermined shapeCognitive mapping of raw material (recognize potential flaws)Invented new tool: handaxeLarger tools, required more prep than H. habilis choppersFirst hominids to make task-specific toolsSome tools used for butchering animal carcasses; others for working with wood; still others for use with veggiesFirst hominids to hunt small to medium size gameProbably the first hominids to use, perhaps even control, fireHints of use at South African site between m.y.a.Fire allows cooking foods (makes meat & veggie consumption easier; lengthen day into the night; keeps predators away; warmth
34 Homo erectus Morphology Body Size and ShapeBasically modern, but more muscled and robustSome individuals very tall (boy from Lake Turkana) = 6 feet tall when an adultLarge brain: cc (overlaps moderns at upper end)Long, low with receding forehead & large browridgesMidfacial pronathism / powerfully built jaw
35 Boy from Nariokotome Very tall hominid at 1.5 mya About 8 years old when he died5’ tall (6 maturity)Legs relatively long in proportion to body as compared to earlier hominidsWell adapted to staying cool in hot, dry climatesFace, molar teeth, chewing muscles smaller than earlier hominids (softer, high-quality - perhaps cooked - foods)Skull-to-pelvis proportions of females: give birth to relatively immature infantsImplications: long infancy-childhood dependency period: good for learning
36 Homo georgicus ?? 1st Hominid to Leave Africa ?? Dmanisi, Georgia (Caucasus Mtns)m.y.a.Late H. habilis or early H. erectusBrain size: ccStature: 1.5 mOldowan tool technology
37 THE RISE OF MODERN HUMANS FromHomo erectusToHomo sapiensViaHomo heidelbergensis
38 The Invasion of Europe Earliest occupation poorly understood Sima del Elefante, Atapuerca, Spain1 million years agoPrimitive stone toolsAnimal bones with cut marksGran Dolina, Atapuerca, Spain800,000 yrs ago6 hominids: share many physical similarities with Homo erectusMay represent link between H. erectus and H. heidelbergensisOften given the name Homo antecessorAll hominid remains exhibit evidence of butchering (cutmarks, dismembering, skinning defleshing)Oldest evidence of human cannibalism
39 Homo heidelbergensis Ancestor to Neanderthals and Us 500,000 to 300,000 years agoAfrica, Europe (none in Asia)Brain larger than erectusSkull more rounded, less robust but still with large brow ridges, receding foreheads & no chinsH. heidelbergensisH. erectus
40 Homo heidelbergensis First BIG GAME hunters By 500 k.y.a. = wooden spears used to hunt large game (rhinos, horses, hippos, giant elk)Cut marks lie UNDERNEATH toothmarksGround minerals to produce pigments (body painting?): kyaNOTE: While heidelbergensis lived in Africa, other hominid species lived elsewhere: H. erectus continued successfully in eastern and southeastern Asia
41 La Sima de los Huesos (The Pit of Bones) A most important H La Sima de los Huesos (The Pit of Bones) A most important H. heidelbergensis site400,000 y.a.32 individualsBodybuilder physiquesPronounced muscle markingsThick layers of hard bone around central marrow cavitiesNot a living siteBurial? / Washed in?“One handaxe does not a ritual make.” - crsmith
42 Homo neanderthalensis European descendants of H. heidelbergensis FemaleEye, skin & hair color speculativeDark haired maleRed-headed maleYoung boy
44 Neanderthals: Ancestors Or Dead Ends? Europe, southwest Asia, central Asia between 200, ,000 years agoMuch controversy overtheir faterelationship to anatomically modern humans (H. sapiens)No other aspect of human evolution has generated as much public interest for so long a time as the story of the Neanderthals.
45 Neanderthals: Earlier Views Until very recently, Neanderthals were most often depicted as brutish, dimwitted, “half man half beast.”
47 Neanderthal Cranial Morphology Cranial cap: 1400 ccLarge midface / large nasal appeture / very big nose that projects forwardLarge gap behind 3rd molarLarge protruding occipital boneMarked neck muscle attachments on skullVery large incisor teethNo chinDouble-arched brow ridge
48 A Comparison: Side by Side With A Relative Brain case: low vs. highNasal opening: large vs. narrowCollarbone: long vs. shorterRib cage: conical vs. cylindricalLimb bones: thick-walled vs. thin-walledHand bones: robust vs. slenderTrunk: short vs. longHips: flaring vs. narrowJoint surfaces: large vs. smallerLower leg: shorter vs. longerBowed limbs vs. straight limbs
49 Explanation for Neanderthal Morphology Cold weather & harsh climate adaptationsStrenuous huntingTheir bodies' relentless demand for calories, especially in higher latitudes and during colder interludes, probably forced Neanderthal women and children to join in the hunt.
51 Neanderthal Culture: Stone tools Mousterian toolkitEffective but simpleChanged little over 100,000 yrs.Trimmed flint nodulesStrike-off lots of flakespredetermined form - retouched)Tool specializationSkin & meat preparationHuntingWoodworkingHaftingSome wooden tools (including thrusting spears) tipped with stone points
52 Levallois Flint Knapping Careful retouching of flakes taken off coresSpecific uses of flakesAnimal butcheringWoodworkingBone & antler carvingWorking of animal hides
53 Neanderthal Culture: Subsistence Extremely successful huntersJabbing spears (not thrown) w/ hafted stone pointsNo long-distance hunting (locally available game)Cave bear, Deer, Woolly rhinoceros, mammoth, wild cattle, reindeer, horse, wild ass, ibex, saigaNeanderthal skeletons often show fracturesFairly efficient gatherersBerries, greens, roots - limited time frame (few weeks)
54 Neanderthal Culture Settlements Open sites, caves, rock-sheltersBuilt structures / windbreaksControlled use of fire: warmth
56 Neanderthal Cannibalism Ritualistic or Nutritional Purposes Possible evidenceFrance & CroatiaFragmentary bones show stone-tool cut marks similar to those found on butchered game animalsSome long bones smashed to get marrow
57 Burying the Dead Intentional Some grave offerings: stone tools, animal bones (flowers?)
58 Neanderthals’s Fate: Part I By 30,000: Neanderthals goneSudden climatic changeLarge game dying out and Neanderthals hunting methods not suitable?Out competed by anatomically modern H. sapiens?Better energy extraction methodsShorter gestation periodsDiseases brought by a.m. H. sapiens?Genetically absorbed into .am. H. sapiens without significant genetic contributions to modern populations?
59 The Fate of the Neanderthals: Part II Interbred with anatomically modern H. sapiens to produce modern Europeans?Four-year-old child buried in a Portuguese rock-shelter 25,000 to 24,500 years agoCzech Republic, male, mixture of Neanderthal and a.m. H. sapiens featuresRecent genetic data indicates no mixing
60 Anatomically modern Homo sapiens: In Our Own Image Descendants of African H. heidelbergensisFirst appear about 200,000Defined morphologically, not behaviorallyTall, almost vertical foreheadSmall to minimal brow ridgesNo retromolar gap (thus impacted wisdom teeth)Cranial cap.: 1350 ( )Pointed chin (uniquely modern trait)High rounded cranium : widest point on sides of parietals
61 A Time of Crisis: 140,000 years ago Mega-droughtMuch of African environment becomes desert - desert-likeDramatic reduction of hominid pops. ( breeding individuals)Hominids forced into refuge areas (principally: south African coastline)Began to exploit new resources (shellfish, penguins, also hunting/gathering on coastal plains) reflects a new versatility
62 Refuge Sites Pinnacle Point, So. Africa (140 - 70 kya) Earliest tools made from beach cobbles; later tools made from stone quarried 20+ km away, then heat treatedSome of earliest evidence H. sapiens living off sea (cooked shellfish) = 70,000 years agoKlasies River Caves, So. Africa ( kya)kya: systematic use of marine resources: ate shellfish, seals, penguins, hunted antelope, gathered plant foods (roasted in hearths built for the purpose)Fire-blackened fragments of human skulls / other bones showing cut marks = Cannibalism
63 Complexity of Culture Blade tools: increased technological abilities Spearthrower (lightweight spears)Small bone & ivory toolsFishhooksTailored skin clothingExpansion into new eco-nichesUbiquitous burial of the deadPostmortem modification commonArt and symbolismCave paintingsPortable art (beads/ carved bone - stone - wood)
65 Leaving Home 95 kya: SW Asia Europe: 46 kya SE Asia: 60 kya Burial of mother/childEurope: 46 kyaSE Asia: 60 kyaAsia: 40 kyaAustralia: 60 kyaAmericas: kya
66 Why do modern humans have different skin colors Why do modern humans have different skin colors? It may all come down to VITAMINS
67 Only Skin DeepSkin color variations are adaptive traits that correlate closely to geography and the sun’s ultraviolet radiation, not race.Skin pigmentation developed as body’s way of balancing its need for vitamin D and folic acid.Vitamin D (calcium absorption for healthy bones)Folic acid (healthy fetuses)Populations closer to the equator have darker skin to prevent:folate deficiencytoo much Vitamin D production
68 We are more alike my friends than unalike. - Maya Angelou