Lecture seventeen

Question 0

When does an open population experience growth?

Answer 0

When birth and immigration&raquo_space; death and emigration

Question 1

What factors reduce inputs relative to outputs?

Answer 1

Biotic - density dependent

Abiotic - density independent

Question 2

What is the difference between biased and unbiased density independent factors?

Answer 2

Biased - reduce fitness (selection)

Unbiased - random mortality

Question 3

What four factors influence population growth in crowded populations?

Answer 3

Intraspecific competition
Predator density
Parasite density
Disease

Question 4

What is the primary underlying assumption of the logistic model?

Answer 4

Population growth is density dependent

Question 5

Does r vary with N?

Answer 5

Yes

Question 6

When do populations increase/decrease in relation to N and K?

Answer 6

Increase when N is below K (r>0)

Decrease when N is above K (r<0)

Question 7

Is K a stable equilibrium?

Answer 7

Yes

Question 8

Inflection point

Answer 8

Peak at half K, growth starts to slow down

Question 9

Does the logistic model represent the quantitative or qualitative dynamics of natural populations?

Answer 9

Qualitative

Question 10

What do density independent factors tend to do?

Answer 10

Reduce populations to far below K and initiate periods of population recovery

Question 11

Thrips: spring summer winter?

Why?

Answer 11

Large pop increase, large pop decrease, pop is stable

Due to reliance on plant pollen as energy source

Question 12

Infrequent and mild environmental fluctuations?

Answer 12

K-selected, density dependent regulation

Question 13

Frequent and extreme environmental fluctuations?

Answer 13

R-selected, density independent regulation