In many sexually reproducing organisms, females make mate choice decision based on male display traits. Several models have been proposed to explain the evolution of exaggeration in male traits. Two of them have been given below in column P and their possible descriptions in column Q. Column P Column Q A. Runaway Selection I. Males exploit a pre-existing sensory bias in females. Females choosing such males have higher quality B. Chase – away Selection II. Female choice for male trait occurs due to perceptual errors leading to poor quality offspring. Thus, females will evolve to run away from males with such traits. III. Female choice for male trait results in a positive feedback loop favouring both, males with such trait and females that prefer them. IV. Males exploit pre-existing sensory bias in females. Females do not benefit by choosing such males, driving the evolution of females that discriminate against such males. Match the models to their appropriate description and choose the correct option.

Correct option is C

There are two prominent models that describe the exaggeration of male traits due to female mate choice in sexually reproducing species:

This model, proposed by Fisher, explains that once a female preference for a particular male trait begins, a positive feedback loop can amplify this trait.
Over generations, both the preference and the trait become more exaggerated, even if the trait does not directly contribute to survival.
Statement iii describes this perfectly: “Female choice for male trait results in a positive feedback loop favouring both, males with such trait and females that prefer them.”
Hence, Runaway selection corresponds to Statement iii.

In this model, males exploit a pre-existing sensory bias in females. However, females do not gain any benefit (unlike in Runaway Selection).
This exploitation leads to reduced fitness in females, and hence over time, females evolve resistance or discrimination against such exaggerated traits.
Statement iv describes this precisely: “Males exploit pre-existing sensory bias in females. Females do not benefit by choosing such males, driving the evolution of females that discriminate against such males.”
Hence, Chase-away selection corresponds to Statement iv.

Option 1 (A - i; B - ii): Incorrect. Statement i relates to sensory bias with benefit to females, more aligned with sensory bias model, not Runaway or Chase-away.
Option 2 (A - ii; B - iii): Incorrect. Statement ii indicates female avoidance due to perceptual error—not a correct fit for Runaway selection.
Option 4 (A - iv; B - i): Incorrect. Statement iv is clearly related to Chase-away selection, not Runaway.

Column P		Column Q
A.	Runaway Selection	I.	Males exploit a pre-existing sensory bias in females. Females choosing such males have higher quality
B.	Chase – away Selection	II.	Female choice for male trait occurs due to perceptual errors leading to poor quality offspring. Thus, females will evolve to run away from males with such traits.
		III.	Female choice for male trait results in a positive feedback loop favouring both, males with such trait and females that prefer them.
		IV.	Males exploit pre-existing sensory bias in females. Females do not benefit by choosing such males, driving the evolution of females that discriminate against such males.