QUESTION 4
4.1. List the three possible outcomes of interspecific competition.
(3)
4.2. Predation is one of the forms of exploitative interactions, involving predator and prey (10)
species and it can affect the abundance of the prey population, serve as agents of natural
selection and influence the evolution of both predator and prey. However, prey species
have evolved a wide range of characteristics to avoid being detected, selected, and
captured by predators. These are categorised as either chemical or behavioural defenses.
List and explain any five (5) chemical predator defense mechanisms that were discussed in
class.
[13)
QUESTION 5
5.1. Distinguish between fundamental niche and realised niche.
(4)
5.2. Study the graph below and describe the two species in terms of:
(8)
(a) Niche width
(b) Extent of niche overlap
(c) Degree of competition
(d) Generalist species vs. specialist species
(e) Potential of becoming extinction if environmental conditions change
Timo 1
[12)
QUESTION 6
6.1. Based on studies of survival by a wide variety of organisms, Population Ecologists have (10)
proposed that most survivorship curves fall into three major categories.
Draw a graph illustrating the three survivorship curves and explain each one of them.
6.2. Population growth is illustrated by population growth curves that are used to describe (7)
growth patterns. Describe and compare the two basic patterns of population growth based
on mathematical models. Also indicate which of the two growth patterns is more common
in nature.
2