HBIO Lecture 4 Evolution

Question 1

things required for evolution

Answer 1

inherited variation (is needed for natural selection to occur)

system of reproduction

changing environment

selective pressures

differential reproductive success (fitness)

Question 2

biotic factors selection pressures

Answer 2

competition
predation
disease

Question 3

abiotic factors selection pressures

Answer 3

climate
topography, e.g. a landslide
habitat

Question 4

how do selection pressures occur

Answer 4

act on the phenotype
act on all stages of the life cycle
may act for many generations

Answer 5

selection pressure that impacts the elderly will have a weaker force than one that impacts foetuses or pregnant women.

Question 6

differential reproduction

Answer 6

survival + reproduction = fitness

Answer 7

more offspring in the future = greater evolutionary fitness

Question 8

example of natural selection in humans

Answer 8

native puna indians in argentinian andes, have a high level of arsenic tolerance

Answer 9

cold climates, large stocky body with short limbs

hot climates, smaller bodyweight with longer limbs

this is about heat loss of protection against heat loss

climate has determined body size

Question 10

are we still evolving

Answer 10

yes, evidence of HIV resistance in regions of Africa

humans have modified their environments in ways that have relaxed selection pressures on many traits

clean water
access to medicines and vaccines
more reliable supply of food

Question 11

how is evolution relevant

Answer 11

evolutionary medicine - uses evolutionary theory to understand health, disease & anatomy

emerging diseases, e.g. COVID-19 & SARS (2002)

origins of disease
- e.g. HIV and SIV share common viral ancestor
- origins of disease instruct our research

treatment of disease
antibiotic resistance
vaccines need to change
drug cocktail

drug development
sources of compounds for drugs
testing on animals with shared common ancestor

Answer 12

mode of transmission relates to the effect of the disease

Answer 13

historically advantageous genes become detrimental in the modern world haemochromatosis

Question 14

evolutionary trade-offs

Answer 14

skin pigmentation:

UV protection of folate levels vs vitamin D synthesis

Question 15

conservation biology

Answer 15

low population numbers = low genetic variation of the gene pool

Question 16

can use evolutionary theroy to explain forensic evidence

Answer 16

interpreting and analysing DNA evidence

population profiles

Question 17

human behaviour as a homology

Answer 17

emotions
relationships with others especially family
parental care
mate choice and long-term pair bonds