Exam 3 Flashcards
Distinguishing traits of hominins
larger brain size, bipedal, parabolic dental arch, reduction of facial projection, think molar enamel
Why move to bipedalism
climate change, bulky food, reduced exposure to sun,
What came first, Bipedalism or brain expansion?
bipedalism
how can we tell that the first hominins were upright?
innominate bones. illium is short and borad and flares out at the top, then twists to the side. toe bone, fragments of femur and tibia
3 reasons of bipedalism
upright provider, unright scavenger, aquatic ape
upright provider
walking frees the hands for carrying
upright scavenger
scavenger can scan territory and walk longer distances
aquatic ape
wetlands provide resources that are not usually eaten by primates, filling a niche
lumpers
approach of classification. tend to characterize similar fossils in the same species
splitters
approach of classification tends to create new species
Late Miocene Hominins
Sahelanthropus tchadensis, Orrorin Tugenensis, Ardipithecus kadabba
Sahelanthropus tchadensis
cranium similar to modern chimps, oldest known species in human family tree, ape like and human like features
Orrorin tugenensis
bipedal (femur), size of chimp, thick tooth enamel, possibly in Gorillini rather than Hominini
Ardipithecus Kadabba
known from very few specimens from six localities in Ethiopia
Early Pliocene Hominins
Australopithecus, widespread in Africa
Aridipithecus ramidus (Ardi)
Ethiopia, brain size of chimp, bipedal, arboreal and terrestrial
Genus Australopithecus
early bipeds, Eastern, Southern, and Central Africa, directly ancestral to humans
law of competitive exclusion
if two closely related species compete for a niche, one will win and the other will become extinct
Australopithecus afarensis
“Lucy”, Easter Africa, Ape and human like
ape: flat nose, projecting lower jaw, small brain case
human: bipedal, small canine teeth
Lucy
Australopithecus afarensis, 40% complete, flat feet
Laetoli footprints
oldest ichnological evidence of bipedalism, Olduvai Gorge, Tanzania
Burtele footprints
Ethiopia, contemporary of A.afarensis, retained divergent big toe
Australopithecus deyiremeda
Ethiopia, smallest teeth among australopithecines
Australopithecus africanus
South Africa, similar to A.afarensis, but rounder cranium with a larger brain and smaller teeth, bipedal but also adapted to the trees
Taung child
A. africanus, first hominin fossil found in Africa. 3 year old child possibly killed by an eagle
Australopithecus garhi
Pliocene- Pleistocene transition, prognathic face, large teeth, arm/leg ration closer to Homo, possible tool-user, small brain
Australopithecus sediba
South Africa, facial features similar to Homo, small brain, pelvis and leg bones suggest a gate between Australopithecus and Homo
Kenyanthropus playtops
Kenya, flat face, small teeth
Late Miocene/ Early Pliocene Hominins
Genus Paranthropus
Genus Paranthropus
often synonymized with genus Australopithecus. “dead end” lineage, sagittal crest, adapted for heavy chewing, early tool makers
Why do so many early hominin fossils come from only a few areas?
widespread across Africa. a lot of the fossil record is either lost or deeply buried
What best described human evolution?
“broken”, not a linear line, but a gradual evolution towards “modern” human features
H. habilis
branches off from main line of the Australopithecus. Eastern and southern Africa, less prognathic, larger brain, cultural manipulation (language, forethought, artistic expression, small teeth
H. habilis tool making
Oldowan tool industry, chopper most common tool, percussion method (requires skill, mental template of what result should look like)
H. habilis fate
remains disappear about 1.8 mya, appears to have evolved into another hominin species
H. rudolfensis
H. habilis? Kenya’s Lake Turkana, known from cranial material, larger than H. habilis (pronounced sexual dimporphism or different species?)
lumpers vs. splitters H. erectus
lumpers believe that all hominins between H. habilis and H. sapiends are H. erectus
splitters believe say that this period of human evolution presents us with a number of relation, but more or less geographically separate species
H. erectus
Africa, China, Europe, Georgia, India, Java, possibly language and fire, hunting, tool making, skull is larger and less apelike, brow ridges and longer skull
Nariokotome Boy
H. erectus, Kenya, 80% complete juvenile skeleton, bigger brain, short arms and long legs, terrestrail
Acheulean tradition
handaxe typifies H. erectus, earliest and simplest of handaxes have been found in Africa
fossils in China
associated with H. erectus, strongly resemble Nariokotome Boy, possible fire use, no Acheulean tools, may have derived from a population of H. ergaster
fossils in Europe
oldest fossils found in Gran Dolina in Spain, entered Europe 1.2 mya
Pleistocene epoch
fluctuating climate, with periods called glacials
intelligence in early hominins
H. erectus seems to have been the first human ancestor to rely on the invented, learned, and passed-down adaptations of culture for survival
control of fire in early hominins
H. erectus was first ancestor able to control fire, burned seeds and flint at Gesher Benot Ya’agov, Isreal, indicate control of fire 800 kys
H. ergaster
large bodies, long legs and short arms, slower growth rate, reduced sexual dimorphism
H. heidelbergensis
southwestern Asia and Africa, changes in stone tool and technology, larger brain, starts making Levallois tools
meat eating in early hominins
increase body size and large brains, Australopithecus-Homo transition, Acheulean tools consistent with meat cutting, hunting
Richard Wrangham’s cooking hypothesis
allows for easier digestion of animal protein and reduction in tooth and jaw size
H. naledi
contemporaries of Neanderthals, Rising Star Cave system in South Africa, small brain, no known tools, legs and feet like modern human
Hobbitses
H. floresienses and H. luzonensis
H. floresienses
short stature, small brains and large teeth, not pathological H. sapien, own genus within Homo
H. luzonensis
another population of dwarf hominins, Philippines
2 possibilities of Neanderthals
1) branch of human family tree that went extinct after appearance of modern humans
2) Descendants of the Neanderthals still alive (interbred with modern humans)
H. neanderthals
Europe and southwest Asia, large brains, limbs were short and robust (cold climates), high levels of strength and endurance,
stone tools in Neanderthals
Mousterian toolmaking tradition, refinement of the Levallois technique, a continuation of the Middle Paleolithic
language in Neanderthals
symbolic thought process, hypoid bone, neural development, hypoglossal canal
compassion in Neanderthals
care for physically disabled members, survival of individuals who had significant health problems
symbolic expression in Neanderthals
polished and incised ivory, possibly worn as jewelry
burial of the dead in the Neanderthals
evidence suggests that they interred their dead and including simple items such as stone or bone implements. Shanidar Cave: 4 burial loaded with flower pollen
Mousterian Tradition
drastic increase in amount of working edge from a core, lighter and smaller, more variety in tool kit
Denisovans
likey evolved from H. erectus in Asia, contemporaries of Neanderthals
Denny
half Neanderthal half denisovan child, 13 year old girl, found in Siberian cave
characteristsics of anatomically modern h. sapiens
increased cranial capacity, vertiacal forehead, non-continuous brow ridge, flat non-projecting face
replacement model
fossils represent extinct forms of humans beings that contributed nothing to the evolution of modern humanity. Pre-moderns couldn’t successfully compete for resources with modern humans and became extinct
according to the replacement model, we should find
oldest fossils in Africa and no where else
intermediate forms only in Africa
chronological overlap between emigrant moderns and indigenous pre-moderns
anatomical differences between modern and pre-moderns outside Africa
genetic differences
sudden arrival of African artifacts in Europe and Asia
multiregional model
evolution of modern human beings process, not an event restricted to a single region. various groups evolved together
according to the multiregional model, we should find:
early versions of anatomically modern H. sapiens in different regions
intermediate forms in all regions
no chronological overlap between premodern and modern forms
anatomical continuity between premodern and modern humans outside Afirca
genetic continuity
artifactual continuity
middle ground / genetic replacement
it may be true that the first anatomically modern human beings spread from Africa, but this does not mean that they simply replaced the pre-modern populations they encountered
According to the intermediate view, we might find:
oldest remains in Africa
some intermediate forms outside Africa
some chronological overlap outside Africa
continuity of regional physical traits in local premodern groups
continuity, and development, in genetic material
continuity, and development, in artifacts
advanced artifacts in H. sapiens
blade tools, African immigrants did not take their technology with them, but immigrants to Europe did
Why were the Neanderthals replaced?
less well nourished, harris lines and enamel hypoplasia, required more food. we had better tools, better heating, better methods of extracting nutrition from bones
Anatomically modern humans in Europe
abundant after 30 kya, cro-magnons, beginning of the upper Paleolithic in Europe
Anatomically modern humans in Australia
lake mungo, sparse populations through the Pleistocene and Holocene, likey required boats
Anatomically modern humans in Americas
people migrated from Siberia, Bering Sea was a land mass during Pleistocene. required boats. Indigenous populations 13 kya
Kennewick Man
controversial humans from WA, interpreted by some as European, used to suggest an Atlantic route, falsified using ancient DNA
