Question

A hypothetical bat species (species 1) lives in a city. Another hypothetical bat species (species 2) established a population in the same city after a number of individuals escaped from a zoo. In isolation, each species prefers to roost in buildings that are three or more stories tall. After species 2 became established in the city, species 1 began roosting only in buildings less than three stories tall, whereas species 2 roosted in buildings three or more stories tall. Observers determined that the bright streetlights at ground level had previously deterred most bats from roosting in shorter buildings. Over many generations of existing in the same city with species 2, species 1 showed changes in eye size and retina structure. Complete the following statements about the two bat species.
_________ of species 1.

a. fundamental niche
b. realized niche
c. character displacement
d. intraspecific competition
e. interspecific competition
f. (-\-)
g. resource partitioning
h. competitive exclusion

Answer 1

Complete question:

A hypothetical bat species (species 1) lives in a city. Another hypothetical bat species (species 2) established a population in the same city after a number of individuals escaped from a zoo. In isolation, each species prefers to roost in buildings that are three or more stories tall. After species 2 became established in the city, species 1 began roosting only in buildings less than three stories tall, whereas species 2 roosted in buildings three or more stories tall. Observers determined that the bright streetlights at ground level had previously deterred most bats from roosting in shorter buildings. Over many generations of existing in the same city with species 2, species 1 showed changes in eye size and retina structure. Complete the following statements about the two bat species.

1. Roosting areas in buildings of any height are the _________ of species 1.
2. Roosting areas in buildings of any height are the _________________ of both bat species.
3. ____________ between the two bat species occurs because both species prefer the same roosting areas.
4. In parts of the city with only tall buildings (over two stories), __________ of species 1 may occur.
5. Roosting areas in buildings that are one to two stories tall are the __________ of species 1 when species 2 is present.

a. fundamental niche

b. realized niche

c. character displacement

d. intraspecific competition

e. interspecific competition

f. (-\-)

g. resource partitioning

h. competitive exclusion

Answer:

1. Roosting areas in buildings of any height are the fundamental niche of species 1.
2. Roosting areas in buildings of any height are the fundamental niche of both bat species.
3. Interspecific competition between the two bat species occurs because both species prefer the same roosting areas.
4. In parts of the city with only tall buildings (over two stories), competitive exclusion of species 1 may occur.
5. Roosting areas in buildings that are one to two stories tall are the realized niche of species 1 when species 2 is present.

Explanation:

• The ecological niche is the synthesis of all the environmental factors that influence the growth, survival, and reproduction of species. These factors also include the interaction between species.  

• The fundamental niche refers only to environmental conditions in which a species can live and survive in the absence of any interaction with other species.

• The realized niche refers to the restricted conditions in which a species can live and survive as a result of environmental physic characteristics and the interaction with other species.
• Interspecific competition refers to the interaction between two or more species that use the same fundamental niche. These species compete for the same resources like food, shelter, or water, among many others. Eventually one of the species dominates and the other is displaced.  

• Competitive exclusion refers to the exclusion of the inferior competitor by the superior competitor when there is not habitat differentiation, and both species can not share the same niche. In this case, the effective niche of the dominant species completely occupies the fundamental niche of the inferior competitor.  

• Resources partitioning refers to one dominant species monopolizing the resources, and the other inferior species use other resources -partially or completely -, migrate or get extinguished.

A way in which species can divide resources is by living in different habitat areas. These species might eat the same food, and can roost in different places within the habitat. This resource partitioning and differentiation in the function of their physical location allows both species to coexist more effectively.  

In the present example, both bat species can coexist in the same city but the weaker bat species (species 1) roost at the top of the shorter buildings while dominant species (species 2) roost at the top of the highest buildings.