Human Evolution Exam 3

Which Rule pertains to relative limb lengths?

Allen’s Rule

Who is likely to get rickets?

Dark skinned person in a gloomy climate

Cynthia Beall found that Tibetan women have alleles for high _____________ in their hemoglobin

oxygen saturation

which of the following is a polygenetic (complext) trait?

skin color

dark skin tones evolved in response to which kind of environmental stress?

strong ultra violet radiation (UVR)

is it possible to define pure races by examining multiple biological traits?

no

Bergmann’s Rule pertains to body size. in what part of its range would you expect the biggest members of a particular mammal species?

in the coldest regions

which continent has the most genetic diversity among its indigenous peoples?

Africa

How much DNA do humans share with each other?

99.9%

Basal metabolic rate is measured when an individual is at rest (T/F)

true

Which kind of primate has the shortest growth period?

Lemur

What does ‘diastema’ mean?

A space in the lower jaw to accommodate the tip of a large canine tooth in the upper jaw

Which primate is likely to have a tooth comb?

Lemur

What does the term 'hallux' mean?

the big toe

What does the term 'prehensile' mean?

grasping

The Prosimian (Strepshirrhine) group of primates has retained many 'primitive' features and its members are often called 'living fossils.'

true

How do marmosets differ from other New World Monkeys?

They usually give birth to twins

What best describes how a loris spends most of its daylight time?

Curled up in a hole of a tree

The lesser apes are known as:

Gibbons and siamangs

What is the term that describes an animal that eats mainly leaves?

Folivore

What best describes the eating habits of the tarsier?

They are completely carnivorous

What best describes an adaptation of colobine monkeys from Asia and Africa?

They have developed a digestive tract that allows them to eat high amounts of fiber and derive nutrition from it.

Of all the non-human primates, the chimpanzee genome is the closest to that of humans. (T/F)

true

How are orangutans different from the other great apes?

They usually live solitary lives

You are a primatologist who wishes to study the origins of monogamous societies.  Which primate would you MOST LIKELY study?

Gibbon

Which statement is FALSE regarding chimpanzee material culture?

Chimpanzees depend on tools to survive

Which technique has been especially useful in deciphering monkey alarm calls?

Playback experiments

Identify some evidence that raptorial birds do (or do not) prey on monkeys.

The distribution of monkey bones at the base of trees that have nests indicate the birds are tearing up monkey carcasses

Male reproductive stragegy is primarily a competition for access to fertile females. (T/F)

true

Which residence pattern is least common?

One male, one female

What is taphonomy?

The study of what happens to a creature after it dies

What is Pangea?

An ancient super continent that contained of all the earth’s landmasses

Most naturally occurring carbon is

Carbon 12

As an archaeologist digs down, deeper and deeper, first she finds rusty nailsand broken glass bottles. A little deeper she finds a distinct layer containingbroken pottery sherds and lots of charcoal. Then even deeper, anotherdistinct layer where she finds chipped stone tools and butchered animalbones. Which of these finds is the oldest?

The one with the chipped stone tools and animal bones

Which of the following would be included in the taphonomy of a dead creature?

1. Analyzing which bones are still present from the original creature and noting which are absent.

2. Using a magnifying glass and looking for marks of stone tools on the bones

3. Looking for carnivore gnawing marks on the bones

The bones of human ancestors are plentiful in many South African caves. How did they end up there?

Their bones tumbled into the caves as their dead bodies were being gnawed on by leopards.

Most dead creatures turn into fossils (T/F)

false

Fossils are the remains of once-living organisms (T/F)

true

It is easy to tell apart races with skeletons (T/F)

false

humans and other primates are very _________

visual

some traits are _______, most traits are ________

simple; complex (polygenetic)

polygenetic traits are strongly affected by the ________

environment

melanin

a pigment made in the top layer of the skin

in dark skinned people, the melanin is a __________

brownish black

in pale people the melanin is ______

reddish brown

Two important nutrients:

1. folate

2. calcium

two kinds of UV radiation:

1. strong

2. weak

two kinds of melanin:

1. dark brown

2. reddish brown

Vitamin D is made in response to _____

UVR

folate examples

dark leafy greens, citrus fruits, beans, lentils, seeds, nuts

Calcium examples

leafy greens, bones of small animals and fish

why do people living near the equator evolve to have dark skin

Melanin is like a shield that keeps fierce UVR from destroying folate, an important nutrient. Folate prevents such birth defects as spina bifida and anencephaly. Dark skin in the tropics is an adaptation to a very serious environmental stress.

what is folate?

a nutrient that we get from food

Folate can be destroyed by

fierce UVR

people in areas with very strong sunlight evolved _______

dark skin

folate is a ___ vitamin

B

people living far away from the equator evolved _______

pale skin

vitamin D is important for ________

calcium absorption

when humans migrated out of Africa they underwent a __________

mutation to lose the dark pigment

weak UVR can get past the melanin and start the __________

vitamin D synthesis

no matter how much calcium we ingest, ___________

it won’t get used by the body without some vitamin D

in order to leave the intestines, ______ must act to allow the calcium out to float free in the blood

Vitamin D

calcium combines with ______ to make the hard and strong mineral that is in your bones

phosphate

collagen makes the bones a little bit _______

bendy

if a child has lots of melanin, but there is weak sunlight, can her skin make enough vitamin D?

no

without enough vitamin D, a person will have ______ as they grow up because there is not enough calcium in their bones

rickets

vitamin D protects against

colon, breast, and prostate cancer

prominence of the nose is an adaptation to _______

humidity

very curly hair may be an adaptation to ______

heat; leaves a cooler layer of air close to the scalp, outer part of hair absorbs heat from sun

humans must maintain an internal body temperature of _____

98.6 degrees

Bergmann’s Rule pertains to

overall size. big bulky bodies deal better with the cold because it is easier to retain core temperature with a large volume to surface ratio

Allen’s Rule pertains to

appendages, especially limbs. longer appendages help to deal with the heat because it is easier to radiate heat with relatively more surface area

cold stress is also handled with __________

physiological responses

examples of physiological responses

1. vasoconstriction

2. shivering

3. increased basal metabolic rate (BMR)

Heat stress is handled with what?

vasodilation, sweating, decreased BMR

temperature adapted populations conform to only Allen’s Rule. (T/F)

false. both Bergmann’s and Allen’s rule

lactase

an enzyme produced in the small intestine that breaks down lactose (milk sugar) into glucose and galactose for absorption

lactose

a natural sugar (disaccharide) found in mammal milk (2–8% content), composed of glucose and galactose, which provides energy and aids in calcium absorption

most people are _____ deficient

lactase

The gene to make lactase got switched off. A mutation evolved to keep that enzyme synthesis active. Why?

adaptation to dairy farming

What are some genetic adaptions to high altitude?

lowering hemoglobin and increasing blood flow

what are some stresses at high altitude?

hypoxia, hypoxanemia, acute mountain sickness

dark skin is abundant in _______

melanin

what are the extra energy requirements for a pregnant woman?

in need of more calories, increased maternal metabolism

pastoralism

a sustainable, extensive form of agriculture involving breeding and herding livestock, such as cattle, sheep, goats, camels, and reindeer, primarily in arid, semi-arid, and cold regions

Why is Africa the most genetically diverse place on Earth?

it is the birthplace of modern humans

Body temperature must be maintained at very close to _______

98.6 degrees

vasodilation increases blood volume in ___________ to bring more of the deep body heat to the surface

peripheral circulation

___ % of heat is simply radiated out

67

evaporation of sweat accounts for ____%

23

_____% is lost through airflow (convection)

10

blood distribution flows ____ from the core when the person needs to get rid of heat

away

why are humans relatively hairless?

sweating, evolution to make evaporation easier

humans can sweat a _____ in an hour

liter

clothing is not desirable in ____________

hot, humid climates

the immediate physiological response to cold is

shivering

during the pleistocene (ice Ages) the body size of many mammals ______ as the climate became colder

increased

Bergmann’s Rule

bigger, broader bodies in cold climates

body proportions are important in regulating _________

body temperature

Allen’s Rule

Appendages are shorter in cold climates, longer in hot climates