Presence of a Gravid Spot Influences Male Mate Choice in Poecilia reticulate

Abstract

Studies have shown that certain factors (i.e. color, size, and age) may influence the mating preferences of the male Poecilia reticulate, or guppies.   Because coloration, shape and size have been observed to influence mating preference, evidence of successful breeding (i.e. female gravid spot) may prove to be another factor for male guppy attraction as well. Since this is a relatively new and understudied aspect of mate attraction in guppy research, our study primarily focused on the strength of attraction when a male is in the presence of a female guppy with a gravid spot. Also, most studies are done on female mate choice, while we are focusing on the mate choices of the male (Newsom, et al, 2015; Godin, Briggs, 1996; Kodric-Brown, 1993; MacLaren, 2006).  Male mate choice has been observed in other species, such as the stickleback and Siamese fighting fish (Rowland, 1982; Dzieweczynski, et al, 2006). To mimic the various parameters displayed on typical guppies while changing particular characteristics (i.e., the presence of a gravid spot), we used 3D printing to create models of female guppies that were designed based on selected parameters that would serve as control and experimental groups.  We observed the amount of time a male guppy spent with different female model guppies and their courting behaviors in order to study the factors that may affect male choice. The key impact of our research is to help figure out the cues that fish use to select mates in order to help other scientists.  Our results showed that the male guppies spent more time, on average, with the female guppy with the gravid spot. This could be because the females that have a gravid spot have proven that they can produce offspring.