Mating Behavior of Cyphoderris Strepitans

Introduction: Cyphoderris Strepitans (sagebrush crickets) are unique in their mating behaviors. The male calls by brushing his tegmina (anterior wings) against each other which creates a sound in the same fashion as plucking a comb with a toothpick. The call alerts females of a male’s presence and may also indicate his sexual status (virgin vs. non-virgin) to females. The male’s fleshy, white, hind wings provide a nuptial food gift to the female as she mounts during mating. While the female is preoccupied with feeding on these hind wings, the male attaches a spermatophore to the female. Post-copulation, the male’s tattered hind wings darken and allow researchers to determine his sexual status: virgin vs. non-virgin.

Purposes: (1) Determine if diet influences male willingness to call.(2) Determine if diet influences female mount-time.

Conclusion

1. Diet vs. # of Periods with Mating Calls

Male sagebrush crickets were divided into two diet groups, with half being on a high and the other half on low diet for two days. High diet crickets were given five pollen grains, a slice of apple (water source), and a piece of cat chow every day. The low diet consisted of 2 grains of pollen and a slide of apple every day. The males were paired with females overnight in a clear plastic box and their behaviors were video recorded. Male calling behaviors were scored by dividing the night up into five-minute periods of time. During video analysis, periods were marked based on whether or not a male called. Total marked periods were determined for each male. As an extension, we decided to examine cricket mass data to determine if the two diets affected mass. Pre and post-diet masses were used to determine the percent change in mass for each individual.

Female crickets were divided into two diets: low and high (same as the males). The females were then placed in a clear plastic box with a male cricket, as described in the previous section. Through video analysis, total mount time exhibited by each female was recorded.

2. Mount time vs. Diet in Females

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# Periods Calling vs. Diet

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Mount Time vs. Diet

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The overall goal of our experiment was to to determine whether diet played a significant role in the mating behaviors of Cyphoderris Strepitans. The first part of this experiment was to determine how diet of a male cricket affected the number of mating calls it performed. The data suggest that diet does not have a significant effect on the number of mating calls performed by males (p=0.937). This conclusion led us to question whether the diets had a significant impact on cricket mass. We compared the pre and post-masses of males on a high diet with the mass of those on a low diet. We found that diet did indeed have have a significant impact on the masses of crickets (p=0.036) In summary, although variation in diet created significant mass differences, it was not shown to create significant differences in calling behavior.

Our final experiment concerned the effects of diet on female willingness to mate. We found that there was not a significant correlation between mount time and female diet (p=0.56), but this conclusion is not definitive because sample size was limited; further testing may be warranted.

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Average Change in Mass vs. Diet

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e Virgin male – intact hind wings Non-virgin male – damaged wings

Left: Cyphoderris Strepitans

Right: A mounted female feeds on the hind wings of a male while he attempts to attach a spermatophore.