Presentation on theme: "The Incredible Journey"— Presentation transcript:
1 The Incredible Journey Human EvolutionThe Incredible Journey
2 Recap – Natural Selection There is variation between individuals in a populationParents pass on their traits to their offspringThe organisms with features that best suit their environment have the best chance of survival and reproductionThose organisms that are able to survive and reproduce pass on their characteristics to their offspringOver time the population will become better suited to its environmentLet’s give it a try...
3 Natural Selection Human Adaptations that have been selected for; Bipedalism (position of the ‘foramen magnum’)Reduction in size of molar teethReduction in jaw sizeIncreased cranial capacityCranial ridge
4 Comparison of skulls CHIMPANZEE GORILLA HUMAN SKULL What features can you identify?What makes the skulls different from one another?
5 Comparison of skullsTop of the skull (cranium) is smooth There is no anterior-posterior crest to hold huge jaw muscles No protruding browNo protruding jaw or teeth (ie the teeth are vertical)No protruding nose boneTeeth are arranged in a parabolic shape rather than a narrow u shapeSmall canines and small incisors Foramen magnum (hole for the spine) is positioned directly underneath the skull not in the back of the skull
6 Australopithecus aferensis Location: Eastern AfricaCranial capacity : ccFossils discovered so far in Tanzania, Kenya and EthiopiaTimeframe: 4.7 – 2.1 million yearsFully bipedal (first!), but arms longer than legsPossibly made tools out of bone teeth and horn (Osteodontokeratic)
7 Australopithecus africanus Location: Southern & Eastern AfricaCranial capacity: ccTimeframe: 3-2 million yearsSlightly greater body sizeSmaller canine teeth than A. aferensisTeeth structured in a more parabolic (‘V’) shape
8 Australopithecus boisei (Oldoway) Location: Eastern AfricaCranial capacity: ccTimeframe: million yearsLargest teeth found in any hominid groupHuge jaw, small incisors & canines, large molars & premolars, parabolic dental structure and sagittal crest present – (hard low quality food)Face is more vertically set
9 Homo rudolphonsis Earliest species of Homo (or maybe Homo habilis?) Cranial capacity: 775ccContention as to whether the fossils are Australopithicus or HomoLack of crestsSmoothly rounded occipital bone compared to Homo erectus
10 Homo habilis “handy man” Location: Eastern AfricaCranial capacity: 800 ccmillion yearsShort molars, small canines, parabolic dental arcadeFull biped, increased leg length, decreased arm length, shorter in statureFossils accompanied by primitive stone tools
11 Homo erectus Location: Africa, Asia, Europe Cranial capacity: ccUseing Acheulian tools: hand axe culture, large game hunting, suggestion of communication, first to use fireSome scientists have split H. erectus into three separate species, based on the geographic region in which specimens have been found: H. ergaster (Africa), H. erectus (Asia), and H. heidelbergensis (Europe).
12 Homo sapien Location: Africa, Asian, Europe, Australia, North America A high, rounded craniumCranial capacity: ccArt & Symbolism, first to produce fire and use languageA steep foreheadA tall and narrow nasal openingA parabolic palate