lecture 9

Question 1

what characteristics of primates allow them to spend a great deal of time in trees? (3)

Answer 1

1. flexible shoulder and hip joints
2. grasping hands
3. excellent depth perception

Question 2

which characteristics are common to all primates? 4

Answer 2

1. erect (upright) or nearly erect posture
2. grasping hands and feet
3. Diurnal (active during the day)
4. complex social behaviour

Question 3

what is the lowest taxonomic group that includes monkeys, apes, and humans?

Answer 3

Anthropoidea

Question 4

what is the lowest taxonomic group that includes only apes and humans?

Answer 4

Hominoidea

Question 5

how has walking patterns of Hominoidea change from the most primitive to the most derived? 5

Answer 5

1. Gibbons and siamangs move by swinging from branches (brachiations)
2. orangutan and bonobos- hands and feet
3. Gorillas- knuckle walking
4. chimpanzees- knuckle walking and bipedal swaggering
5. Homo sapiens (humans)- upright posture and bipedal locomotion

Question 6

which homonin 3 characteristics changed with the evolution from early to modern humans?

Answer 6

1. smaller build
2. less-protruding brow ridges
3. more prominent chin

Question 7

what evidence suggests that modern humans originated in Africa?

Answer 7

independent genetic studies of mitochondrial DNA and Y chromosome indicate that all human populations are descended from a common ancestor that originated in Africa and then migrated to various regions on Earth

Question 8

which ape species spend the most time on ground (3)

Answer 8

Gorillas, chimpanzees, and bonobos

Question 9

what trait allows researchers to distinguish between apes and humans

Answer 9

bipedal locomotion. Humans are bipedal, apes are not.

Question 10

what evidence suggests that Neanderthals and modern humans represent 2 distinct species

Answer 10

mtDNA sequence data: the differences between gene sequences of Neanderthals and humans are much greater than the differences between any 2 modern humans

Question 11

Primate character: erect (upright) or nearly erect posture=

Answer 11

= flexible hip and and shoulder joints

Question 12

Primate character: grasping hands and feet=(3)

Answer 12

=1.opposable thumb (and/or big toe),

2. nails not claws,
3. fingertips with many sensory nerves

Question 13

Primate character: Diurnal (active during the day) (2)

Answer 13

1. forward facing eyes with overlapping fields of vision

2. rely more on vision than smell

Question 14

Primate character: complex social behaviour (2)

Answer 14

1. large, complex brains- great capacity to learn

2. small broods(1 hatching or birth)- extended parental care

Question 15

how has the social structure of Hominoidea change from the most primitive to the most derived? 5

Answer 15

1. Gibbons and siamangs - family groups/ solitary
2. orangutan- solitary/family groups
3. Gorillas- 2 to 65 per group
4. chimpanzees and bonobos-20 to 130 per group
5. Homo sapiens (humans)-doesnt say but i think large communities

Question 16

def of primates

Answer 16

lineage that includes humans, apes, monkeys, and their close relatives

Question 17

4 key derived traits of primates

Answer 17

1. erect / nearly erect posture
2. grasping hands (or feet)
3. diurnal (active during the day)
4. complex social behaviour

Question 18

adaptations needed for 1. erect / nearly erect posture (1)

Answer 18

-flexible hip and shoulder joints

Question 19

adaptations needed for 2. grasping hands (or feet) (3)

Answer 19

• opposable thumbs (and/or big toe)
• nails not claws
• fingertips with many sensory nerves

Question 20

adaptations needed for 3. diurnal (active during the day) (1)

Answer 20

• forward facing eyes with overlapping fields of vision (rely more on vision than smell)

Question 21

adaptations needed for 4. complex social behaviour

Answer 21

• large complex brains (great capacity to learn)

- small amount of offspring - extended parental care

Question 22

4 characteristics of New World Monkeys (example = spider monkey)

Answer 22

• weigh less than old world monkeys
• arboreal (lives in trees)
• diurnal
• prehensile (grasping) tail as a 5th limb

Question 23

3 characteristic Old world monkey (example baboon, vervet monkey)

Answer 23

• heavier than New World monkey
• arboreal/walk
• no prehensile tails

Question 24

Hominoidea apes have 4 characteristics

Answer 24

1. lack a tail
2. much larger than monkeys
3. vertebral column more stable
4. complex behaviour

Question 25

locomotion of gibbons and siamangs

Answer 25

brachiation-moves swinging from branches

Question 26

locomotion of orangutan

Answer 26

hands & feet

Question 27

locomotion of gorillas

Answer 27

knuckle-walking

Question 28

locomotion of chimpanzees

Answer 28

knuckle walking and bipedal swaggering

Question 29

locomotion of humans (homo sapians)

Answer 29

have adaptations that allow an upright posture and bipedal locomotion

Question 30

hominins=

Answer 30

modern humans and our bipedal ancestors

Question 31

hominin differ from apes by

Answer 31

upright posture and bipedal locomotion

Question 32

bipedal locomotion freed hands to become ...

Answer 32

specialised for other activities e.g. tool use

Question 33

5 adaptations for bipedal locomotion

Answer 33

1. lower spine becomes curved, shorter & more stable- absorbs shock 2. hip bones became shorter and wider 3. strong knees & ankle joints- more support for the weight of the body 4. length of thigh bone increased stride 5. angle at which spine connects with skull increases stability of head while walking

Question 34

Ardipithecus (4.4 mya) (2)

Answer 34

1. brain size of chimp - less protruding face - smaller canines 2. Probably walked bipedally - but still had long curved fingers & opposable big toes

Question 35

Australopithecus (East, central & South Africa) | 4 species

Answer 35

1. A. anamensis (4mya) 2. A. afarensis (3.5mya) 3. A. africanus (3 mya) 4. A. sediba (2 mya)

Question 36

Early humans: homo habilis who is their most likely ancestor

Answer 36

Australopithecus

Question 37

Homo erectus (1.8 mya) 6 characters

Answer 37

1. taller 2. larger brain 3. thicker skull 4. protruding brow ridges 5. made fairly sophisticated tool (incl. hand axes) 6. groups moved out of East Africa about 1.5 mya

Question 38

Archaic humans (<0.5 mya) - descents of - include a species

Answer 38

- descents of homo erectus | - Included Neanderthals:built shelters, made complex tools, may have used speech and some buried their dead

Question 39

H. naledi (300-200kya) share characteristics shared with other Homo (3)

Answer 39

1. lower limbs (locomotor traits) - long lower limb, strong insertions for gluteus maximus , human-like foot and ankle 2. Hands (manipulation) - morphology of wrist, thumb and palm -enhanced object manipulation 3. Jaws (chewing) - small teeth

Question 40

Modern humans: homo sapiens (3)

Answer 40

1- smaller build 2- less protruding brow ridges 3-more prominent chin

Question 41

Out of Africa when and what 2 studies support this

Answer 41

modern humans migrated out of Africa and into Europe and Asia about 200 000 to 100000 years ago - mtDNA sequences suggest an African ancestry for all modern humans - Y chromosomes studies confirm that all modern humans are descendant of a single migration out of Africa

Question 42

Australopithecus (East, central & South Africa): Ape-like characters (3) Human-like characters (2)

Answer 42

Ape-like characters 1. protruding jaws 2. pointed canines 3. small skull & brain Human-like characters 1. enamel and teeth 2. partly or fully bipedal

Question 43

``` Early humans: homo habilis, earliest humans (2.3 to 1.7 mya) occupied woodlands and savannas of eastern and southern Africa. 3 characters ```

Answer 43

1. mostly vegetarians, scavengers 2. Co-occurred with species of Paranthropus 3. Had bigger brains than Australopithecus and Paranthropus - probably 1st homonin to use tools

Question 44

H. naledi (300-200kya) share characteristics shared with Australopithecus

Answer 44

brain & pelvis structure

Question 45

H. naledi (300-200kya) share characteristics shared with humans

Answer 45

body structure and size

Question 46

who drove archaic humans to extinction

Answer 46

homo sapiens because they competed for resources

Question 47

recent data suggests modern humans interbred with..

Answer 47

archaic humans, including Neanderthals, outside of Africa as recently as 35 000 ya