Mating Preference in Poecilia Reticulata When in the Presence of Shelter

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Past studies prompted us to predict that shelter would significantly affect mating success. A study by Darden and Croft (2008) indicated that female guppies (P. reticulata) chose to seek refuge, even in high-risk areas, in order to avoid male harassment. Another study conducted by Jones and Kaiser and Hecht (1998) demonstrated that the availability of shelter had a significant effect on juvenile production in the Swordtail Xiphophorus helleri. The results of these studies led us to our prediction and suggest our results to be irregular.

The unexpected results may be due to a number of different methodological and biological factors. During our experiment, we observed only 2 guppies (P. reticulata) at a time in each of the tanks. Due to such a small subject pool and controlled environment, it eliminated all elements of competition and sexual selection. In accordance to that, female guppies (P. reticulata) could have been exhibiting a negative preference for the male that she was exposed to, therefore reducing the chances of interaction and mating success. Some of the trials we conducted were between juveniles and adults; therefore the inconsistency in ages could have also affected preference and the male’s level of sexual aggression. The female guppy (P. reticulata) in 2 of our trials became ill, which resulted in her lack of movement and initiative to interact. Human error could also account for the unexpected results. There could have been discrepancies in our recording process. The distorted vision through the tank while observing the interactions could have resulted in us falsely recording times.

In order to make this study more sound, we could have used a larger subject pool to ensure that competition and sexual selection takes place. We could have regulated the age gap between male and female guppies (P. reticulata). We could have conducted more trials in order to create more data. We could have conducted this experiment with a different species. We could also expand our studies and test the success rates of mating in the presence of shelter as well as predators.

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References:

Bokides, D., Lou, Y., Hamilton, I. M., 2012. A model of sexual selection and female use

of refuge in a coercive mating system. Proceedings: Biological Sciences 279(No 1741): 3209-3216.

Darden, S. K, Croft, D. P., (2008). Male harassment drives females to alter habitat use

and leads to segregation of the sexes. Biol. Lett. 4: 449-451.

Head, M. L., Brooks, R., 2006. Sexual coercion and the opportunity for sexual selection

in guppies. Animal Behaviour 71: 515-522.

Magurran, A. E., Seghers, B. H., 1994a. Sexual conflict as a consequence of ecology:

evidence from guppy, Poecilia reticulata, population in Trinidad. Proc. R. Soc. Lond. 255(No 1342): 31-36.

Magurran, A. E., Seghers, B. H., 1994b. A cost of sexual harassment in the guppy,

Poecilia reticulata. Proc. R. Soc. Lond. B 258: 31-36.

Trivers, R. (1972). Parental investment and sexual selection. Chicago, Illinois: Aldine

Publishing Company.

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Graphs:

[pic 1]

Fig. 1. Each error bar is constructed using 1 standard error from the mean.