Population Ecology

Question 1

what is a population

Answer 1

• group of organisms of the same species, that interbreed, live in the same area at the same time
• size is the total individuals present
• density is the number of individuals in a particular area

Question 2

what are some research methods

Answer 2

• directly counting: not really feasible
• sample a small amount, make inferences about the whole
• quadrat for plants
• mark and recapture: some learnt o avoid recapture or try to be captured for food
• electronic tracking

Question 3

what is species distribution?

Answer 3

• relationship of a population and a habitat
• uniform: equal spacing, territoriality (penguins)
• random: unpredictable (flowers)
• clumped: clustering, live in large groups (elephants)

Question 4

what is demography?

Answer 4

• statistical study of the changes a population undergoes over time
• birth and death rates, sex ratio, age structure, life expectancy
• life tables show life expectancy based on life history

Question 5

what are survivorship curves?

Answer 5

• comparisons of life histories of different populations
• type 1: humans and primates usually, lower youth deaths
• type 2: birds, death is equal at all ages
• type 3: trees, fish, high chance of death in youth

Question 6

what is exponential growth

Answer 6

• populations with unlimited resources grow rapidly and decline rapidly on the inverse
• best seen in bacteria

Question 7

what is logistic growth

Answer 7

• “struggle for existence” - competition for resources
• S shaped curve