Does sexual selection evolve following introduction to new environments?

Rapid evolution and behavioral plasticity following introduction to an environment with reduced predation risk

“…We did not detect a difference in female discrimination of males between populations or the evolution of preferences for bright males in the introduced populations, supporting findings that preferences evolve slowly (Easty, Schwartz, Gordon, & Hendry, ). Unexpectedly, females did not prefer bright males in this study, perhaps because they found all males attractive.…”

“…Thus, we may have detected a preference for orange coloration and greater discrimination if we had used males that varied more dramatically in color, or if we had used non‐virgin females. On the other hand, our findings may correctly reflect a lack of female preference for orange coloration in these populations, as other studies have found female preferences for orange coloration are not universal across guppy populations (e.g., Easty et al, ; Endler & Houde, ; Houde & Endler, ; Hughes, Houde, Price, & Rodd, ; Schwartz & Hendry, ).…”

Female preference for novel males constrains the contemporary evolution of assortative mating in guppies

“…Consistent with previous studies on experimentally translocated guppies (e.g., Endler 1980;Kemp et al 2009), our results show rapid evolution of male signaling traits, albeit at a faster rate than was suggested by those previous experiments. Furthermore, consistent with mate choice studies (see review by Easty et al 2011) indicating female preference for larger males and higher carotenoid-based (i.e., orange and yellow) and melanin-based colors (i.e., black), we found that female preference in our study was linked to the first canonical variate of our signaling traits, the axis accounting for most variation in male size, and relative yellow and black area, but not orange. Recently, Gordon et al (2015) directly assessed selection on and the evolution of male secondary sexual traits (i.e., size, and carotenoid-based and melanin-based colors), in the Guanapo source population and 2 introduced populations (Lower Lalaja, here called Introduction 1, and Upper Lalaja) during the first year postintroduction.…”

“…Furthermore, the one previous introduction experiment that tested for assortative mating did not find it (Easty et al 2011). Yet, the introduction used by Easty et al (2011) experiment did not include replicate populations, did not consider parasites, and used methodologies that might not have been optimal with respect revealing the contemporary evolution of mate choice (Easty et al 2011).…”

“…For instance, females sometimes show preferences that are conserved across populations (Schwartz and Hendry 2007), females sometimes prefer "novel" males (Hughes et al 1999), female preferences can be frequency dependent (Hughes et al 2013), and males can use "sneaky" copulations to circumvent female choice (Ojanguren and Magurran 2004). Furthermore, the one previous introduction experiment that tested for assortative mating did not find it (Easty et al 2011). Yet, the introduction used by Easty et al (2011) experiment did not include replicate populations, did not consider parasites, and used methodologies that might not have been optimal with respect revealing the contemporary evolution of mate choice (Easty et al 2011).…”