Chapter 7: Density Dependence

Question 1

two types of density dependence

Answer 1

• negative density dependence
• positive density dependence

Question 2

possible causes of negative density dependence

Answer 2

• intraspecific competition
• disease
• predation

Question 3

negative density dependence is …

Answer 3

stabilizing

Question 4

negative density dependence is stabilizing

Answer 4

can help pull a population towards an equilibrium size range

Question 5

another name for equilibrium size range

Answer 5

K or carrying capacity

Question 6

K or carrying capacity

Answer 6

• when population is at K, r is approx 0
• it is a range, not a single value

Question 7

what is K affected by

Answer 7

• density dependence
• external density independent factors

Question 8

positive density dependence

Answer 8

• vital rates &/or population growth rates increase as density increases
• destabilizing

Question 9

positive density dependence: destabilizing

Answer 9

pushes big populations to get bigger, small populations to get smaller

Question 10

positive density dependence at low population numbers

Answer 10

positive density dependence = allee effect

Question 11

mating and caring for young mechanisms

Answer 11

• mate limitation
• cooperative breeding

Question 12

foraging advantages mechanisms

Answer 12

• detection and access to food
• cooperative feeding

Question 13

predator mediated mechanisms

Answer 13

• predator detection/confusion/defense
• predation rate changes with prey numbers