Question

The probability of local extinction increases with body size when there is forest degradation, loss, and fragmentation. Consider the following hypotheses for the vulnerability of larger-bodied species: 

(P) Larger-bodied species tend to have smaller population sizes.
(Q) Larger-bodied species require larger territories/home ranges. 
(R) Larger-bodied species have higher absolute resource and energy requirements.

Which one of the following options correctly lists all potential reasons for the vulnerability of larger-bodied species? 
 

• A. P and Q only
• B. P only
• C. P and R only
• D. P, Q, and R

Hint:

Larger animals require more resources, space, and have smaller populations, making them more vulnerable to extinction in fragmented habitats.

Answer 1

The Correct Option is D

The vulnerability of larger-bodied species in fragmented habitats can be explained by the following hypotheses:
[6pt] - (P) Larger-bodied species tend to have smaller population sizes.: Larger animals typically have slower reproductive rates and lower population densities. As habitat fragmentation occurs, these species are more prone to local extinction due to limited gene flow and a higher risk of inbreeding.
[6pt] - (Q) Larger-bodied species require larger territories/home ranges.: Larger animals need more space to find food, mates, and suitable habitats. Fragmentation reduces the available space, making it harder for these species to survive and reproduce.
[6pt] - (R) Larger-bodied species have higher absolute resource and energy requirements.: Larger animals require more resources to maintain their body mass, making them more susceptible to habitat degradation that reduces the availability of food or shelter.
Thus, all three factors (P, Q, and R) contribute to the vulnerability of larger-bodied species, which makes (D) the correct answer.