Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOL 200 > bipedalism > Flashcards

bipedalism Flashcards

1
Q

who are the only primates to walk upright most of the time

A

humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where is our centre of gravity

A

just above our waists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how many hypotheses are there as to why we became bipedal

A

at least 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why did we become bipedal

A

climate change: drying of forests and more savannah - came down from trees
free our hands for tools and hold babies
improve line of sight on the savannah
throw projectiles
combination of many

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are some major adaptations since divergence from chimpanzee line

A

bipedalism: 4 million BP
stone tools: 3.3 million BP
lack of body hair: 2.5 million BP
long-distance running: 2 million BP
larger brain size/body size: 2 million BP
hunting large prey: 1.9 million BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is Lucy

A

australopithecus afarensis
3.2 million BP
was 3.5 ft tall
walked upright
small brain: bipedalism predated large brain and nakedness
rib-cage resembling gorilla: large volume for plant-based diet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how did bipedalism change our anatomy

A

our neck became longer and straighter and joined the skull centrally rather than dorsally
our back became supple and bended
our knees became large: outsized knees and angles thigh bones - our femur angles inward from the pelvis to knee

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why do we have arches in our feet

A

for springiness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how do we walk compared to apes

A

we have graceful gait compared to the waddling of apes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how do we walk

A

we have large gluteus maximus and achilles tendon unlike any ape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

can humans outrun cheetahs

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how fast did the running ape run

A

20 mph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why do large prey not outrun predators

A

they lose heat by panting and only run for about 9 miles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how did we outcompete (running) neanderthals

A

endurance running ability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how many km/day did modern HGs walk/run

A

> 10 km/day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is responsible for our hairlessness

A

a single mutation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

who is the only primate that can’t carry babies hands free

A

humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are some incomplete adaptations of bipedalism

A

lower back pain
pregnancy and lower back pain
disk problems
spondylolysis
ACL injuries
ACL tears
Achilles tendon ruptures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the most common type of pain in adults in the US

A

lower back pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what parts of the body does lower back pain involve

A

muscles, nerves, and bones between lower edge of rib bottoms or buttocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what % of lower back pain occurs at any time

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what % of lower back pain occurs during any particular month

A

25%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what % of lower back pain occurs during a lifetime

A

40% (up to 80% in western countries)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

at what age does lower back pain start

A

20-40 and increases over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
how much weight to pregnant women gain
15 kg
26
what is an adaptation women have that helps them with lower back pain from pregnancy
they can arch their lower back over 3 vertebrae compared to 2 in men
27
where is the extra pressure in pregnant women located
lower vertebrae
28
what do disks do
cartilage that lubricates the joints between the vertebrae in the spinal column solid but compressible to absorb shock and strain
29
what causes with a slipped disk
uneven pressure creates protuberances in the disk
30
what % of males develop sciatica
4.8%
31
what % of females develop sciatica
2.5%
32
what is spondylolysis
stress fracture of lower vertebral arch caused by repetitive stress
33
what does ACL stand for
anterior cruciate ligament
34
what does the ACL do
connects the femur to the tibia, under the kneecap
35
where did the strain of running and jumping spread in apes
among 4 limbs and muscles
36
where is the strain in the ACL in humans
strain is carried by bones when leg is straight
37
why are humans vulnerable to tearing in sports
because of rapid turns and jumps
38
how many people per yr do ACL tears affect in the US
100,000/yr
39
how to fix ACL tears
reconstructive surgery
40
what are the most dangerous sports for ACL tears
women's soccer men's football women's gymnastics
41
why are women more at risk for ACL tears
ACL is relatively smaller in men
42
what does the achilles tendon do
connects calf muscle to heel
43
what is the importance of the achilles tendon
crucial for upright activities
44
is the achilles tendon short or long in great apes
short
45
why did the achilles tendon expand in humans
to take on a greater role in humans
46
why is the achilles tendon subject to injury
because of the strain during sports or movement there is no built in redundancy exposed at the back of the leg
47
how many people does a ruptured achilles tendon affect
1 per 10,000 people/yr
48
can you walk after a ruptured achilles tendon
no
49
is there any reliable data on % of babies dying
no
50
in the past what % of babies die as children
50%
51
in the past what % of babies die in the first year of life
25%
52
what % of infants don't survive their first year in western countries
<0.5%
53
what % of infants die at birth in Canada
0.4%
54
what % of infants die at birth in the global south
5-10%
55
in 1955 what % of newborns died in the US compared to the global south
US: 3% global south: 15-20%
56
what % of orangutans in the wild die at birth
1-2%
57
when did humans match orangutans in infant mortality rate
the 20th century
58
what % of maternal deaths in birth in the US
0.024% (1/4000)
59
what % of maternal death in the global south
up to 1%
60
what is the probability of surviving 10 births
0.9; 90% chance of surviving
61
what was the maternal mortality rate in the paleolithic and ancient civilizations era
at least 1-2%
62
what is breech birth
feet first
63
what does a breeched birth mean for mortality rate in mothers and babies
3x higher maternal mortality rate 5x higher infant mortality rate
64
what % of people require a caesarean delivery
0.1-10%
65
how long does labour take in humans
around 9 hours
66
how long does labour take in apes
around 1-2 hours
67
is it commons for mothers to die in apes
no
68
how do gorillas give birth
while still eating and caring for young
69
how do chimpanzees give birth
they seek solitude
70
what is the difference between how humans give birth vs apes
we universally seek assistance
71
how to babies emerge from the birth canal
baby enter birth canal face up or sideways and then turns 90 degrees to emerge face down
72
what is the Obstetrical dilemma hypothesis
our evolution of larger heads (to fit larger brains) clashed with our evolution of narrower hips that allow efficient locomotion deliver babies prematurely to accommodate hip width
73
what is the most reliable way to identify the sex of a skeleton
hip width
74
what does a wider pelvis result in
swinging motion during walking
75
what does the obstetrical dilemma hypothesis predict
normalizing selection on humans birth weight
76
what are the critiques of the obstetrical dilemma hypothesis
women are no less efficient running/walking than men maybe hips are just big enough 8 billion humans on earth with farming: diet higher in carbs babies are getting bigger western medicine
77
what % of deliveries are c-sections
5-10% on the rise
78
what % of deliveries are c-sections in the US
1/3 60% of which are for convenience
79
what % of deliveries are c-sections in Canada
28% in 2016 19% in 1997
80
what will c-sections eventually do
remove selection against large baby size

BIOL 200 (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions