​Consider predators with a choice between two prey types: a big prey 1 which has energy value E1, handling time h1, and search time S1; a small prey 2 with energy value E2, handling time h2, and search time S2. According to the optimal foraging (diet) theory, when will the predator preferentially select prey 2?​

Correct option is A

Explanation-

Prey 2 will be preferentially selected when:

$$\frac{E_2}{h_2} > \frac{E_1}{h_1 + S_1}$$

$$\begin{aligned}&\text{Where:} \\&E_1, E_2 = \text{Energy gained from prey 1 and 2} \\&h_1, h_2 = \text{Handling time for prey 1 and 2} \\&S_1 = \text{Search time for prey 1}\end{aligned}$$

This option is based on optimal foraging (diet) theory, which states that predators should maximize energy intake per unit time.

Incorrect Options-

Option b: "When the abundance of prey 1 is very high"
Incorrect. Abundance is not directly factored in this equation. Even if prey 1 is abundant, prey 2 may still be more profitable depending on the energy/time ratio.
Option c: "When the abundance of prey 1 and prey 2 are equal "
Again, the decision depends on profitability (E/h) and search time, not abundance alone.
Option d: "When E2/h2 = E1/h1"
Incorrect. This ignores search time (S1), which is important in prey 1’s evaluation.

Correct option - Option a -When E2/h2 > E1/(h1+S1)

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