Chp 19 and 20

Question 1

Gene tree versus species tree problem

Answer 1

Gene tree may not accurately reflect species tree

Question 2

Gene tree

Answer 2

depicts evolutionary relationship of a single gene or multiple genes

Question 3

H. sapien interbreeding with neanderthal

Answer 3

1) occured twice with western and eastern neanderthal populations
2) occurred with only eastern and asian H. sapiens

Question 4

2 pieces of evidence supporting interbreeding between neanderthals and european/asian humans

Answer 4

1) 20-30% of neanderthal DNA when looking at genomes of the entire human population
2) Minimal neanderthal DNA found in African lineages

Question 5

Sahelanthropus tchadensis

Answer 5

Earliest hominin, very strong brow ridge, evidence of bipedal movement, low foramen magnum, no more shredding canines, small brain

Question 6

Aridipithecus

Answer 6

Probable early hominin
Foot morphology shows tree gripping
Pelvis suggests climbing and walking combo

Question 7

Australopithecus

Answer 7

Archaic hominins

Question 8

Archaic hominins

Answer 8

have tool building, better techniques for dating these species

Question 9

Australopithecus afarensis

Answer 9

Lucy
Used Mode 1 tools
Found footprints of two individuals walking side by side

Question 10

Australopithecus megadont

Answer 10

archaic hominins
Big cheek bones
large muscle attachment on skull for large chewing muscles
Larger chewing muscles for eating raw roots and tubers

Question 11

Homo habilis and Homo rudolfensis

Answer 11

Skull features begin to look more like modern humans
prominent brow ridge
small brain

Question 12

Homo eragaster

Answer 12

possibly same species as homo erectus
premodern hominins
larger brain
taller

Question 13

Homo erectus

Answer 13

Mode 2 tools
Fire for cooking and warmth
Body plan very similar to modern hominins

Question 14

Homo heidelbergensis

Answer 14

evolved from erectus or eragaster
Gave rise to modern humans
Mode 3 tools
Group hunting

Question 15

When did homo heidelbergensis split?

Answer 15

600k years ago

Question 16

Homo floresiensis

Answer 16

Small brain
Very short due to island life
Large flat feet
hunted pygmy elephants

Question 17

Homo naledi

Answer 17

Found in rising star cave
small brain like australopithecus
Hand and feed like Homo genus
Cranial structure like homo erectus and homo habilis

Question 18

Which species shows first evidence of use of a burial chamber?

Answer 18

Homo naledi

Question 19

Homo neanderthalensis

Answer 19

bigger, stronger, heavier than homo sapiens
Strong brow ridge
Social
buried dead
fire
probably speech
Hunted large game
South/western Europe and some of west Asia

Question 20

When did homo denisovan split?

Answer 20

200k years ago

Question 21

Homo luzonesis

Answer 21

found in the philippines, very minimal info

Question 22

Homo sapiens

Answer 22

Larger, rounded brains
Smaller teeth
pronounced chin
smaller brow ridge

Question 23

When did homo sapiens leave Africa

Answer 23

~60k years ago

Question 24

When did denisovans and neanderthals stop existing with H. sapiens

Answer 24

30k years ago

Question 25

Upper paleolithic lifestyle

Answer 25

better tools hunting language advanced culture/behavior bone and ivory tools music burial ceremonies

Question 26

Evidence for the out of africa hypothesis

Answer 26

1) genetic evidence - those are African descent have the most genetic variation in mtDNA and Y chromosome DNA 2) technology spread multiple times 3) Gradual spread of H. sapiens across the globe

Question 27

Multiregional hypothesis

Answer 27

Homo erectus originally left Africa and evolved into the other species, which experienced gene flow and all converged to H. sapiens

Question 28

Germ theory of disease

Answer 28

1) pathogen ID 2) Antiseptic surgery 3) Antibiotic 4) Need for sanitation

Question 29

Four levels to the question, why we get sick?

Answer 29

1) Proximate - immediate mechanism, how disease works 2) Developmental - how pathology came about often organism lifetime 3) Evolutionary - How natural selection and other evolutionary processes leave body vulnerable to disease 4) Phylogenetic - look at evolutionary history and close relative to see how an organism is vulnerable

Question 30

proximate level to why we get sick?

Answer 30

immediate mechanism, how disease works

Question 31

Developmental level to why we get sick?

Answer 31

how pathology came about often organism lifetime

Question 32

Evolutionary level to why we get sick?

Answer 32

How natural selection and other evolutionary processes leave body vulnerable to disease

Question 33

Phylogenetic level to why we get sick?

Answer 33

look at evolutionary history and close relative to see how an organism is vulnerable

Question 34

Clinical based treatment includes these two levels to the question, why we get sick?

Answer 34

Proximate and developmental

Question 35

Preventative based treatment includes these two levels to the question, why we get sick?

Answer 35

Evolutionary and phylogenetic

Question 36

6 evolutionary explanations for why we get sick

Answer 36

1) The red queen, humans are locked in arms races with their pathogens which evolve more rapidly 2) Natural selection has not caught up with the rapid changes in the environment 3) Laws of physics and nature of Biology impose trade-offs on what an organism can do 4) NS lacks foresight, stuck in relics of the past 5) NS favors reproductive success at expense of vulnerability of disease 6) Some defenses may be unpleasant but are beneficial - reproductive health over well being

Question 37

Costs of a fever

Answer 37

feeling crappy metabolism Super high fevers are dangerous

Question 38

What is the smoke alarm analogy for fevers?

Answer 38

false negatives are more costly, better to think there is a fire every time you cook rather than miss a fire

Question 39

3 predictions behind smoke alarm predictions

Answer 39

1) cost of a fever is less than getting sick, better to have one even if unnecessary 2) Intervention is okay in some cases, antibiotics only if necessary 3) Shouldn't always stop fever

Question 40

Levy's guidelines to reduce antibiotic resistance

Answer 40

1) avoid bad bacteria (don't eat raw food) 2) Antibacterial soaps and cleaners ONLY to prevent infection 3) Don't use unneeded antibiotics 4) complete antibiotic course 5) Avoid spreading infections by using proper hygiene 6) Use drugs that target a narrow range of bacteria 7) Isolate patients infected with resistant bacteria

Question 41

Three hypotheses of virulence theory

Answer 41

1) coincidental evolution hypothesis 2) the short-sighted evolution hypothesis 3) The tradeoff hypothesis

Question 42

Coincidental evolution hypothesis

Answer 42

just happens to cause issues when inside you, typically benign in the environment

Question 43

Short-sighted evolution hypothesis

Answer 43

Evolves within adaptations that are beneficial to the pathogen’s prevalance in the host, but may harm its reproduction (polio virus does really well in one reaches neuron, but harms host and prevents spread)

Question 44

The tradeoff hypothesis

Answer 44

Natural selection should favor pathogens that strike an optimal balance between the costs and benefits of harming their hosts (cordyceps fungus has weevil walk to optimal location to spread spores)

Question 45

Why do we die?

Answer 45

Disposable soman hypothesis

Question 46

Disposable soman hypothesis

Answer 46

It is more beneficial to invest in reproduction over repair because sooner or later something will get you