L8 Tosh - Limits to Population Growth

Question 1

What 2 things limit population growth?

Answer 1

1. Intraspecific competition

2. Interspecific competition

Question 2

What is the main outcome of intraspecific competition?

Answer 2

Decreased contribution of individuals to subsequent generations - a decrease in comparison to if there was no competition

Question 3

What 3 things are essential or greatly affect intraspecific competition

Answer 3

1. Limited resources - so that individuals are competing for a limited supply
2. Reciprocity must be present (all competing individuals are essentially the same)
3. Density dependence - this is very important as the impact of competition is greater the higher the number of individuals present

Question 4

What are the keyu characterisitcs of density dependence?

Answer 4

1. intraspecific competition and DD are closely linked
2. when there is intraspecific competition, its effect on survival and fecundity is density dependent
3. Not all DD effects arise from intraspecific competition - such as interspecific competition, predation, parasitism, and disease
4. DD effects usually regulate the population size

Question 5

If reproductive rate is high compared to carrying capacity, what may happen?

Answer 5

Overcompensation may occur:

• population grows so fast it over shoots K
• the overly large population crashes to a smaller one
• then then repeats