Post on 18-Nov-2014
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Hominid EvolutionHominid Evolution
Origins of HominidsOrigins of Hominids
◊ Most crucial change was Bipedal Locomotion
◊ Other changes include• Expansion of the brain, larger birth
canal, reduction of face, teeth and jaws◊ All of these occurred 2 million yrs. After
bipedalism
◊ Journal Entry 1
◊ Most crucial change was Bipedal Locomotion
◊ Other changes include• Expansion of the brain, larger birth
canal, reduction of face, teeth and jaws◊ All of these occurred 2 million yrs. After
bipedalism
◊ Journal Entry 1
Why did Bipedalism occur?Why did Bipedalism occur?
◊ See farther◊ Carry food◊ Carry tools and weapons
◊ See farther◊ Carry food◊ Carry tools and weapons
AustralopithecinesAustralopithecines
◊ First definite Hominids◊ Genus of Hominids until C. 2 Mill yrs.
Ago◊ Somewhere b/t 3 and 4 mill. yrs ago. ◊ At Laetoli footprints found proving
bipedal locomotion◊ Although Bipedal, still may have
spent time in trees for sleep and shelter
◊ First definite Hominids◊ Genus of Hominids until C. 2 Mill yrs.
Ago◊ Somewhere b/t 3 and 4 mill. yrs ago. ◊ At Laetoli footprints found proving
bipedal locomotion◊ Although Bipedal, still may have
spent time in trees for sleep and shelter
Types of SpeciesTypes of Species
◊ Australopithecus afarensis◊ Australopithecus africanus◊ Australopithecus robustus◊ There are more Think of
hominids as a Bush, not a timeline!
◊ Australopithecus afarensis◊ Australopithecus africanus◊ Australopithecus robustus◊ There are more Think of
hominids as a Bush, not a timeline!
Australopithecus AfarensisAustralopithecus Afarensis
◊ Debate as to whether diff. species or not
◊ Footprints found to prove bipedalism
◊ Between 3 and 4 million years ago
◊ Debate as to whether diff. species or not
◊ Footprints found to prove bipedalism
◊ Between 3 and 4 million years ago
Australopithecus AfricanusAustralopithecus Africanus
◊ Jaw of ape◊ Teeth of humans◊ S-shape spine similar to man
◊ Jaw of ape◊ Teeth of humans◊ S-shape spine similar to man
Afarensis vs. AfricanusAfarensis vs. Africanus
◊ Features of skull, teeth, and jaws that are less apelike in africanus
◊ Some debate different species
◊ Features of skull, teeth, and jaws that are less apelike in africanus
◊ Some debate different species
Australopithecus robustusAustralopithecus robustus
◊ 2-1 million years ago◊ Larger molars and premolars◊ Smaller canines◊ Well-developed cranial crests and ridges◊ Much heavier◊ Taller: 4.5- 5 ft. tall
◊ 2-1 million years ago◊ Larger molars and premolars◊ Smaller canines◊ Well-developed cranial crests and ridges◊ Much heavier◊ Taller: 4.5- 5 ft. tall
Ancestor?Ancestor?
◊ Australopithecus robustus is not thought to be an ancestor to the Homo species
◊ Lived during same relative time as Homo species
◊ Australopithecus robustus is not thought to be an ancestor to the Homo species
◊ Lived during same relative time as Homo species
ChangesChanges
◊ Expansion of brain◊ Reduction of face, teeth, and jaws◊ Babies born less mature at birth
◊ Journal Entry #2
◊ Expansion of brain◊ Reduction of face, teeth, and jaws◊ Babies born less mature at birth
◊ Journal Entry #2
Expansion of the brainExpansion of the brain
◊ Had relatively small cranial capacities
◊ Reason?• Why would brain size have increased?
(Think Evolution types)
◊ Possible reasons:• Increased as a result of tool making
◊ Had relatively small cranial capacities
◊ Reason?• Why would brain size have increased?
(Think Evolution types)
◊ Possible reasons:• Increased as a result of tool making
Reduction of Face, Teeth, and JawsReduction of Face, Teeth, and Jaws◊ Lower face not as protruding◊ Reduction in size of
• Face• Cheek bone• Jaw
◊ Lower face not as protruding◊ Reduction in size of
• Face• Cheek bone• Jaw
Now on to species of HomoNow on to species of Homo◊ Different ideas on how Homo
genus evolved◊ Some say from Africanus◊ Some say from Afarensis◊ About 2 millions years ago
◊ Different ideas on how Homo genus evolved
◊ Some say from Africanus◊ Some say from Afarensis◊ About 2 millions years ago
Homo habilisHomo habilis
◊ Larger brain absolutely and relatively than Australopithecus
◊ Found in East Africa◊ Slightly Larger and more
developed brain◊ Stone tools?
◊ Larger brain absolutely and relatively than Australopithecus
◊ Found in East Africa◊ Slightly Larger and more
developed brain◊ Stone tools?
Homo erectusHomo erectus
◊ 1.6 to 1.3 millions years ago◊ Skull generally long, low, and
thickly walled◊ Flat frontal face◊ Prominent brow ridges◊ Relatively small teeth modern
arrangement
◊ 1.6 to 1.3 millions years ago◊ Skull generally long, low, and
thickly walled◊ Flat frontal face◊ Prominent brow ridges◊ Relatively small teeth modern
arrangement
Cont…Cont…
◊ Fully developed vision area of brain
◊ Larger areas of speech, sensory, memory and motor areas of brain
◊ Neck down, almost same as Homo sapiens
◊ Fully developed vision area of brain
◊ Larger areas of speech, sensory, memory and motor areas of brain
◊ Neck down, almost same as Homo sapiens
FireFire
◊ Fire first appears 1.5 mill. Years ago
◊ Only able to spread out after development of fire
◊ Journal Entry
◊ Fire first appears 1.5 mill. Years ago
◊ Only able to spread out after development of fire
◊ Journal Entry
Stone toolsStone tools
◊ Acheulean “hand axe”• 1.5 mil. Years ago• Used for butchering, digging,
pounding
◊ Toolmaker first shaped the core, and prepared a striking platform at one end
◊ Knock off flakes
◊ Acheulean “hand axe”• 1.5 mil. Years ago• Used for butchering, digging,
pounding
◊ Toolmaker first shaped the core, and prepared a striking platform at one end
◊ Knock off flakes
HuntingHunting
◊ Homo erectus began to hunt medium sized animals• Spears, stone throwing, and fire• Needed to plan and work in groups
◊ Homo erectus began to hunt medium sized animals• Spears, stone throwing, and fire• Needed to plan and work in groups
Neanderthal Neanderthal
◊ Becoming Human◊ Becoming Human