1
Q
HUMANS IN ANIMAL KINGDOM
A
- mammalia and into the genus Homo.
2
Q
SIMILARITIES BETWEEN APES AND HUMANS
A
- opposable thumbs that allow for power grip
- two hands with five fingers (toes too)
- no tail
3
Q
DIFFERENCES BETWEEN APES AND HUMANS
A
H - bipedal, A - quadrupedal
H - large, developed brain, A - small less dev brain
H - narrow flat face, A - wider sloping face
4
Q
EVIDENCE OF COMMON ANCESTORS
A
- fossil evidence
- genetic evidence
- cultural evidence
5
Q
WHAT DOES FOSSIL EVIDENCE LOOK AT
A
looks at:
- bipedalism
- dentition
- palate shape
- brain size
- cranial and brow ridges
- prognathism
6
Q
PALEONTOLOGY
A
study of fossils
7
Q
BIPEDALISM
A
- walking upright on two feet
- foramen magnum in the middle of the skull enables bipedalism, as opposed to it being at the back of the skull
8
Q
ADVANTAGES OF BIPEDALISM
A
- upright bodies expose less surface area to the sun - less overheating
- hands are free to use tools and hunt
- adaptable - can occupy wider variety of habitats
9
Q
PALATE SHAPE
A
- was previously narrow and rectangular, later became more u-shaped and then became wider and more curved in humans
10
Q
CRANIAL AND BROW RIDGES
A
- apes have prominent c&b ridges for attachment of chewing muscles
- decreased in size over time and completely reduced in humans
11
Q
DENTITION
A
- teeth size decreased with evolution
- apes have prominent canines, but human canines are the same size as other teeth
- tooth enamel thickened over time
- diastema disappeared over time
12
Q
DIASTEMA
A
the large gap between the incisors and canines
13
Q
PROGNATHISM
A
- when the jaw protrudes and there is no chin (in apes)
- apes have sloping face bc of this
- teeth smaller over time = reduced prognathism
14
Q
BRAIN SIZE
A
- cranium size inc in most fossils over time = brain capacity inc as well
- ape cranium is small and elongated, less dev brain
- humans have rounded skull = bigger cranium and larger dev brain
15
Q
MORE COMPLEX HUMAN BRAIN HELPED WITH
A
- well developed hand-eye coordination
- the capacity for language
- the use of fire
16
Q
GENETIC EVIDENCE
A
- very rare to extract DNA from a fossil
organisms contain: - chromosomal DNA
- mitochondrial DNA
17
Q
COMPARING mtDNA
A
- by comparing mtDNA of living hominids, scientists can determine when the evolutionary paths of humans and apes separated
- many diffs = sep occured earlier
- more time for mutations to occur = more variation
18
Q
CULTURAL EVIDENCE: TOOLS
A
the production and use of tools (and other cultural practices like fire making and art) are suggested as further evidence of common ancestors for living hominids
19
Q
TYPES OF TOOLS
A
- made of stone, sometimes bone and wood
- some sharp stones, others carved blades
- provide access to wider variety of foods
20
Q
THREE MAIN TOOL CULTURES
A
- oldowan
- acheulian
- mousterian
21
Q
MAIN HOMINID GENERA WITHIN THE HOMINID GROUP
A
- ardipithecus
- australopithecus
- homo
22
Q
ARDIPITHECUS
A
- 5,8 - 4,4 mya
- transition between apes and australopithecus
23
Q
CHARACTERISTICS OF ARDIPITHECUS
A
- probably bipedal
- long arms for climbing trees
- small brain capacity
- sloped face
24
Q
AUSTRALOPITHECUS
A
- first bipedal primates
- lived between 4,5 and 1,4 mya
25
CHARACTERISTICS OF AUSTRALOPITHECUS
- bipedalism and upright walking
- large brow ridges
- u-shaped palate
- protruding jaw, no chin
26
FIVE WELL KNOWN AUSTRALOPITHECINES
- Taung child
- Mrs Ples
- Lucy
- Little Foot
- Australopithecus sediba
27
TAUNG CHILD
- found by Raymond Dart
- was of a 3-4 yr old child
- small brain, human-like teeth, bipedal
28
MRS PLES
- Robert Broom
| - possibly bipedal, no protruding canines
29
LITTLE FOOT
- Ron Clarke
| - bipedal, short arms, similar hands to humans
30
CHARACTERISTICS OF HOMO
- bipedalism
- flat face
- wide, curved palate
- larger brain
- no brow ridges
31
HOMO HABILLIS
- smaller body and larger brain than Australopithecus
| - fossil found in Tanzania
32
HOMO ERECTUS
- closer to modern humans than Australopithecus
| - large bodies, thick skulls and large teeth
33
HOMO TIMELINE
- habillis
- erectus
- neanderthalensis
- sapiens
34
HOMO SAPIENS
- direct ancestors of modern humans
- developed better skills and more advanced technology
- had a large brain capacity
- used tools and wore clothing made of various materials
35
OUT OF AFRICA HYPOTHESIS
- states that all human life originated from Africa and Homo sapiens migrated from Africa 50000 mya
- resulted in more Hs replacing He around the world
36
EVIDENCE OF AFRICAN ORIGINS
- genetic links (chro, mit, Y-chro DNA)
| - fossils and artifacts of hominins (Africa has largest numbers)
37
THE USE OF GENETIC LINKS (OOA) mtDNA
- mtDNA of diff pops are compared to determine the extent of genetic variation in a pop
- more variation = more mutations
- high variation in Africa = Africans are the oldest humans
38
STRUCTURAL CHANGES IN HUMANS IN TERMS OF BIPEDALISM
- the moving forward of the foramen magnum
- the vertabral column in humans is S-shaped for flexibility & shock absorption
- longer arms, shorter legs
- stronger knee-joints
- arched foot, instead of flat
39
CHROMOSOMAL DNA DEF
occurs in the nuclei of all cells and contains all the genetic information
40
COMPARISON OF CHROMOSOMAL DNA
determine how closely related they are, more similarities more closely related
41
cultural changes that distinguishes modern humans from primates
- development of speech and language (improved comm and social interaction) (helped with hunting and defence)
- tools
42
Oldewan tool culture
- oldest tools found, found in Tanzania
- 2,6 to 1,5 mya
- choppers, flakes, scrapers
- rock, stone
43
Acheulian tool culture
- more advanced, found in France
- 1,5 mya to 250 000 ya
- hand-axes, picks, cleavers
- stone, wood, bone
44
Moustertian tool culture
- found in France
- 250 000 to 50 000 ya
- flakes, scrapers, points
- hand axes w carefully shaped blades
45
what did refined tools help with
- gave access to better food, clothing and shelter
| - more comf and complex lifestyles
46
microliths
smaller blades that formed part of arrowheads and fishhooks
47
fossils found in Great Rift Valley
h-h and h-e in Kenya
| ardi and austra in Ethiopia
48
the Cradle of Humankind
the richest source of hominin fossils in the world, 40km North of Jhb
49
importance of CoH
- produced over one third of the world's hominin fossils
| - scientists have concluded that humans originated in Africa
50
why is it important to know the dates of fossils
- to compare diff fossils and observe evolutionary trends
| - determine the order in which different life forms appeared on Earth
51
radiometric dating
- based on radioactivity, if the age of the rock of the fossil is known, it is assumed that the fossils are the same age
- if fossils are older than 50 000 years
52
relative dating
- based on the fact that deeper layers of sed rock are older than shallow years
- therefore deeper layers = older fossil
- not very accurate
53
alternatives to evolution
creationism
literalism
intelligent design
54
reproductive isolation
occurs by means of various isolating mechanisms which prevent pops from exchanging genes
55
mechanisms of reproductive isolation
behavioral patterns, physiological processes that prevent diff species from crossbreeding an producing viable offspring
eg.) prezygotic and postzygotic
56
prezygotic division
occur before fertilization and prevent mating and/or fert from taking place
57
postzygotic division
after fert and cause abnormal zygote development so that no viable / fertile offspring can be produced
