Osteological TermsStandard Anatomical PositionFacing forward with hands facing forwardAnteriorFrontPosteriorBackSuperiorTowards the topInferiorTowards the bottomMedialTowards the midlineLateralTowards the outside, away from midlineProximalPart of an element that is closest to the skullDistalPart of the element that is furthest away from the skullVentralBelly sideIn bipeds, similar to anteriorDorsalBack SideIn Bipeds, similar to posteriorPaleoanthropologyThe study of human evolution and the fossil recordGoalsTo identify species (especially paleospecies) To understand the relationship among the fossils among each other, but also with modern humans To gain insight into the behavior of those speciesMultidisciplinaryZooarchaeologistsStudy of animal remains at a siteTaphonomistsOsteologyGeologistsArchaeology“The Big 3” (what separates humans from apes)Culture (belief systems, religion, art)Brain Size (humans are more encephalized)Obligate bipedalismDID NOT HAPPEN SIMULTANEOUSLYBipedalitySkullForamen magnumHole where your skull sits on your vertebraeCentrally located in humansMore posteriorly located in the great apesSpinal CurvatureMore curved in humans to balance weightGreat apes have a shallow curved/ straight spinePelvis ShapeBiped:more square shaped pelvis that is shorterIlea: anteriorly/posteriorly orientedSlightly angled forwardQuadruped/ Great apeFlatter, rectangular pelvisIlea more lateralMore narrowFemurBicondylar AngleFemur is angled medially in bipedsFemur is almost straight up and down in quadrupedsNeck lengthNeck of femur longer in bipedsFeetPosition of big toeApes have an opposable big toeHypotheses for BipedalityFreeing the hands“man the hunter”“woman the gatherer”Better view of the open countryEnergy EfficiencyPaleoanthropologyEast Africa—Earliest fossil record coming from hereGeologically:Rift valley—plates coming together. Lots of seismic activity.Dating—good for getting absolute dating.If found, fossils are usually in good shape.Fossils can “erode out” of the ground, fossils often found through erosionEarthquakesVolcanic activitySouth AfricaFossils when found are embedded in brecciaBrecciaCement-like matrix of sand, pebbles and soil that encases fossilsLimestone quarriesSubterranean cavesLimestone quarriesVery specific to South African fossilsDated primarily through biostratigraphyTermsPost-Orbital Constriction (POC)Narrowing behind the eye orbitPrimitive, ancestral traitOver time becomes less and less constrictedSupra-Orbital Torus (SOT)Enlarged area of bone above the eye orbitAncestral trait, stays for a long time but not in humansPrognathismAnterior projection of the maxillaOrthognathismLack of anterior projection of the maxillaVertical maxillaThis is what modern humans areSagittal CrestLarge ridge (crest) of bone on top of the skull in the centerRuns front to backA lot of variation earlier in time, no modern humans have a sagittal crestNuchal CrestLarge ridge of bone on posterior/inferior aspect of skullAncestral traitAngled occipital crestbone in back of skull that forms an angleGracileSmall and smooth area of boneRobustLarge and rough area of boneSpoilerA fossil that is found that “messes up” the traditional theories of the fossil recordMiocene FossilsSahelanthropus tchadensisFound in ChadAbout the size of a modern chimpanzee6-7mya Significant. Will need to know for test!!Oldest fossil that they are fighting about if its in the human lingeage or notCentral AfricaDated by biostratigraphyPrimitive craniumHas a small brain, post orbital constriction, Angeled occipital regionPossibly bipedalWhy it is importantIt is a paleospeciesIt is an ape like skull shape, but with a reduced maxilla and its foramen magnum suggests bipedalismIts old (6 to 7 million years old), makes it the oldest possible hominidGeography—central AfricaMiocene/Pliocene FossilsArdipithecus ramidus (Ardi)PrognothicApe-like skullMix of ancestral and derived traitsAncestral traitsParts of the skull—small brain.Ape like teethPost CraniallyMix of bipedal characteristicsAlso some arborealityRounded pelvisOpposable toeElongated arms, not a knuckle walkerNot a true brachiaterBipedConsidered the last common ancestor (LCA) between apes and humansKenyanthropus platyopsIts date and morphology make it a better candidate for a human ancestor than afarensisAustralopithecusMost well-known of all the fossil groupsAustralopithecus afarensis3.9-3.0 million years agoEast African fossilSmall cranial sizeSmall sagittal crestFairly robust nuchal crestRelatively large canine teethPrognothic3.5’-4’ tallSome hints of bipedalism“Lucy”Discovered in 1974Dated at 3.2 million years oldBipedalismShe is an afarensis“Selam”Young child (3 to 4 years old)Nearly complete skeleton3.4 million years old (afarensis)Found in ChinaLaetoliArchaeological site in Tanzania3.5 million years oldAt this site, they have found 84’ worth of footprintsAttributed to afarensis because of the dateAustralopithecus africanusSouth Africa3-2 myaEndocastThe solid impression of the inside of a skullCan tell many important things about brain sizeTaungArcheologist found a south African fossil and claimed he had found a 3 to 4 yr old childSuggested it would have been bipedal and had a large brainFacial skeleton and endocastName of the site and fossil*******COMPARE CONTRAST WITH LUCY ON TESTAustralopithecus garhiIts name means “surprise”Approx. 2.5 myaEarliest tools arriving around this time, earliest genus homo around this timeNearby to garhi’s site were the bones of butchered animal bones and primitivge toolsUntil then, the use of tools had been attributed to the genus homoMay have been using toolsHomo erectus1.8mya- 500,000yaDuboisWent to Trinil, JavaFound a Single skull cap and a femur.Cranial traitsBrain size increased by around 33%Vault height is biggerDecrease in post orbital constrictionDecrease in proganathism (face is flatter)Tooth size has decreasedExpanded in nuchal regionSome are more angled, others are more roundedDental arcade is parabolicStill has a large supraorbital torus (brow ridges)Supra-toral sulcusSpace directly above the supraorbital torus, “shelf”Posteriorly sloping foreheadLower cranial vaultFrom the base to the top, it is not as tallWidest point of their skull= baseHomo erectus does not have a sagittal crestSagittal keel (sloping point)Post CraniallyTallerover 5’ tallmodern limb proportionslong legs/short armsmodern morphologypelvis=bipedaldid not vary drastically from