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36 Cards in this Set
- Front
- Back
Common Features of Early Hominins (4 species) |
Few Fossils Found at single sites Similar dates Geographically limited |
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Adaptive Profile of Early Hominins (4 species) |
Bipedal (uncertain..a hominin?) Reduced canine size/honing complex (uncertain/questionable) Other cranio-dental features are primitive Small brain and body size
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Four Species of Early Hominins |
Sahelanthropus Tchadensis Orrorin Tugenensis Ardipithecus Kadabba Ardipithecus Ramidus |
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Sahelanthropus Tchadensis: Dates & Locations
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Discovered in 2002 in Chad, Africa Toros-Menalla site Previously a lightly forested location 6-7 mya |
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Sahelanthropus Tchadensis: Overall Characteristics |
9 fossils found (sample size) Huge brow ridges/suborbital torus Reduced prognathism Small brain size, cranial vault shape similar to chimp Slight Reduction in canine/honing complex (human-like) U-shaped dental arcade (chimp-like) Thin enamel (diet similar to chimps, enamel thicket than chimps & thinner than human) Large incisors (chimp-like) Controversy over bipedal (foramen magnum like early homo's) |
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Toumai (TM 266) |
1/9 Sahelanthropus Tchadensis fossils found Most complete fossil of the species Fossil (large) brow ridges are sloping due to pressure during fossilization Small brain size Cranial vault shape similar to chimps |
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Cranial Capacity for Humans & Chimps |
Humans: 1375 average (range 1150-1750) Chimps: 395 average (range 285-500) |
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Orrorin Tugenensis: Dates & Locations |
Discovered in 2000 in Kenya, Africa Tugen Hills Previously forest near streams and lake Also open woodland 6 mya (k/Ar) |
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Orrorin Tugenensis: Overall Characteristics |
12 fossils found (sample size) Cranial/post-cranial fragments Well-preserved femur (locomotion) Large Femur head: sign of bipedalism in hominin Thick Enamel: sign of omnivore Large Upper Canine (chimp-like) Large Incisors (ate-fruit: chimp-like) Curved finger bone (chimp-like) Primitive humerus (for-climbing?: chimp-like) |
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Millennium Man |
Orrorin Tugenensis (original man from tugen hills) |
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Ardipithecus Kadappa: Dates & Locations Ground Dwelling bipedal (basal) base, before root |
Discovered in 2004 in Ethiopia (Middle Awash) 5.8-5.2 mya (K/Ar) |
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Ardipithecus Kadappa: Overall Characteristics |
17 fossils found (sample-size) larger sample size than most, less information/evidence Flat toe implies bipedal; only evidence implying bipedalism Small incisors (human-like) Curved finger bone (chimp-like) Honing complex is present (resembles female chimp) White explains Ramidus is ancestor of Kadabba (Scientifically questionable) Found in lower sediments than ramidus
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Ardipithicus Ramidus: Dates & Locations
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Discovered in 1994 in Ethiopis (Middle Awash) Forest Environment 4.4 mya (K/Ar) Ardi Skeleton published in 2009 |
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Ardipithicus Ramidus: Overall Characteristics Ground dwelling bipedal root ancestor |
Isolated Teeth & Cranial/post-cranial fragments Hands are very large relative to body (chimp/gorilla-like) Thin enamel (chimp-like) Reduced honing complex (human-like) Smaller Canine (human-like) Reduced Progathism (human-like) Anterior foramen magnum (bipedal hominin) Brain size: 300-350cc (chimp-like) Pelvis shows bipedal and arboreal traits Long fingers, curved phalanges (chimp-like) Opposable toe (climbing? chimp-like) |
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Ardi |
Ardipithicus Ramidus Skeleton Published in 2009 Nearly Complete Skull |
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Australopithecus anamensis: Dates & Locations |
Ana=Lake (Lake Turkana)
Discovered; in 1995 in Kenya, East Turkana by Leakey 4.2-3.9 mya (forest environment) |
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Australopithecus anamensis: Overall Characterisitics |
22 fossils found (sample size) Reinforced tibia (clearly bipedal) Intermediate enamel thickness (diet more varied than chimps) Dentition dimilar to Ar. Ramidus but less primitive Intermediate canine size |
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Australopithecus Afarensis: Dates & Locations |
Afar=Region in Northern Ethiopia "afar triangle" (3 plates)
Discovered; in 1974 in Kenya, Ethiopia (Hadar), Tanzania (1st fossil w huge geographic range) by Don Johanson 3.8-3.0 mya |
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Australopithecus Afarensis: Overall Characteristics |
Several hundred fossils (1st fossil like this) Lucy & Laetoli footprints Clearly bipedal: wedge-shaped vertebrae Sexual dimorphism (size of skull not of dentition/canine) Brain size: 350-500cc Dentition similar to A. Anamensis but less primitive Child fossil found; Dikika Baby
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Lucy |
Australopithecus Afarensis No feet Clues to ancestor had ape & human characteristics |
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Laetoli Footprints |
Australopithecus Afarensis Tanzania Only foot evidence atm |
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Dikika Baby |
Australopithecus Afarensis from Dikika, Ethiopia found encased in sandstone 3 year old child 3.3 mya fossil preserved almost entire skeleton almost complete skull: spine and shoulders underneath foot found nearby and other body parts Looked at adult teeth in skull (CT scan) to find out 3 years old |
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Australopithecus Bahrelghazali |
Discovered in 1995 3.5-3.0 mya One fossil (sample-size) Teeth Largely Unknown (is it afarensis?) Canine small No honing complex Main significance; geography: tells us they lived in North Central Africa |
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Kenyanthropus Platyops (Plat=Flat) |
Discovered in 2001 3.5 mya Cranium (kind of crushed/cranial frags) Toe bone Flat face, small molars (distinct from afarensis) Existed with afarensis (more human-like..who is human ancestor?) Too crushed for reliable analysis? Distinct species
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Australopithecus Africanus |
Earliest hominin species discovered; in 1924 3.5-2 mya Discovered in South Africa (Sterkfontein&other cites) Hundreds of fossils (similar to afarensis/good evidence of species) Earliest Hominin to inhibit South Africa Taung Child, Mrs Ples, Little Foot |
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Taung Child |
Australopithecus Africanus 3 year old child endocast of brain from sediment during fossilization skull, mandible, brain endocast (rock in shape of brain) First Africanus discovered most likely descendant of Afarensis migrated from east to south Africa
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Mrs. Ples |
Australopithecus Africanus Adult (1st adult discovered) Cranium (sample) More derived than afarensis; larger brain rounded braincase less prognathism smaller C and I teeth |
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Little Foot |
Australopithecus Africanus complete skeleton more human-like than afarensis gives more africanus evidence |
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Australopithecus Sediba Well, Spring (Water spring) |
Discovered in 2010 (most recently discovered) in Malapa (near Sterkfontein Caves in S.Africa) 2 mya Juvenile and Adult Female skeleton Other frags (good evidence)
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Australopithecus Sediba; similarities to australopiths |
Small Brain Small Body Long Arms Primitive Feet Bipedal |
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Australopithecus Sediba; similarities to genus 'homo' |
Smaller teeth Less projecting face Pelvis (supports 3rd hypothesis that homo evolved in S.Africa) |
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Paranthropus aethiopicus |
First found in Ethiopia, Africa East Africa, now found all over Discovered in 1985 2.7-2.5 mya Several skulls, jaws, cranial frags More primitive than boisei and robustus (small brain, large Incisors) Ancestor by cladogenosis to Afarensis (similar traits) No postcrania |
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Paranthropus boisei |
First known from East Africa Discovered; in 1959 in Tanzania by Lewis Leakey 2.3-1.2 mya Several dozen skulls, many jaws, many cranial frags Very sexually dimorphic (same dentition, different skull size) Robust traits more derived(exaggerated) than aethiopicus Distant ancestor to afarensis (postcrania indicates body size similar) Coexisted with homo |
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Paranthropus robustus |
Only paranthropus in South Africa Discovered in 1938 Discovered in S. Africa at Skartkans & other cites 2.0-1.5 mya Several dozen skulls, jaws, cranial frags Isotopic studies suggest they ate animal protein Bone tools; Antelope bones with sharpened ends (1st evidence of tool use) |
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Specialized cranio-dental adaptations of Paranthropus species |
Clearly not human ancestor Extreme adaptations due to diet (unique) Sagittal crest very visible (large chewing muscles) Extremely developed temporalis and masseter muscle large mandible tiny incisors premolar is said to be molarized, molars very large flared zygomatics (which makes face dished) |
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Australopith Group: 3 genera |
Australopithecus, Kenyanthropus, Paranthropus 10 species: hundreds of fossils wide geographic distribution (all parts of Africa) 1-4 mya small bodies (3 1/2- 5 1/2 ft tall) small brain (larger than chimps) clearly bipedal moderate prognathism U-shaped dental arcade w large I, reduced C, large molars |