Question

1. How has the population of crickets on the Hawaiian island of Kauai evolved in response to natural selection imposed by parasitoids?

2. This evolutionary change in the population of males has led to a new set of tradeoffs. What fitness ADVANTAGE do flatwing crickets have over normal crickets?

***These questions are from this article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1834006/

Answer 1

1. A normal male crickets have specially equipped wings with a scraper and teeth that produce a chirp when rubbed together that we hear as cricket song which attracts females. But a flesh eating parasitoid maggots, offspring of the fly, Ormia ochracea, which invaded Hawaii from North America are attracted by the the chirping sound of the crickets and attack them. The fly larvae burrow into, killing the host.

To protect themselves from their enemy large number of male crickets on the Hawaii Island of Kauai stopped chirping quickly. They lost their ability to chirp as a result of evolutionary adaptation to their wings through natural selection. The feat was achieved over less than 20 generations.

The mutation had erased almost all the wing structure that help to make the sound,leaving the wings flattened but still airworthy. So there is a evolutionary change in population of male crickets

2. The normal male crickets are attacked by flies and eaten by maggots, while the silent males or flat wing males evade the flies and survive. Though the female crickets generally won't mate with a male unless he sing a courtship song, the researchers proved that females are equally willing to mate with silent males and normal males.