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Editor's Notes

• #3: Mate choice is really common in nature and is major component of sexual selection. Some individuals, usually females, preferentially mate with the most ornamented members of the opposite sex, usually males. While females of a species tend to agree on preferring more ornamented—brighter, bigger, faster signaling, or louder—individuals, there’s still variation. Some females still mate with males that are less bright, smaller, and signal slower or quieter. Females can vary in their choice behavior for a lot of reasons, but I’m particularly interested in how they use their social environment to decide who to mate with.
• #4: One of the ways females can tell who is in their social environment is to attend to the sexual signals they can perceive around them. When sexual signals propagate over some medium, like vibrational or acoustic signals, the quantity and attractiveness of those signals tell females something about the quantity and attractiveness of the males they might mate with.
• #5: The effects of the social environment produce a cool feedback loop: the strength and direction of selection influence the composition of the social environment, which influences female responses to male signals, which then determine what selection on those same signals looks like. For this study, I’m focusing on how the social environment influences individual females’ responses to sexual signals.
• #6: A key component of plastic phenotypes is the timescale on which they are plastic. Some traits, like song learning in many birds, become fixed based on experience during critical windows in juvenile development. Males and females learn their songs and preferences, respectively, based on what they hear around them during this critical window. Similarly, the size of many insects is fixed once they reach adulthood, but for physical limitations: if you have an exoskeleton, you don’t get to grow anymore. Other traits, in contrast, can remain flexible throughout adulthood: adult female Polistes fuscatus paper wasps learn the faces of nestmates (as opposed to strangers) and adjust their aggressive behavior accordingly.
• #7: So with this study, I looked at three related questions: is reproductive behavior fixed based on experiences during development? Or does it remain flexible throughout adulthood? Or if experiences during both stages are important in determining female behavior, what are their relative roles?
• #8: I looked at these questions in the Pacific field cricket, Teleogryllus oceanicus, which is native to Australia and throughout the Pacific. It was introduced by human activity to Hawaii, where I work.
• #9: T. oceanicus males sing two distinct songs: one is a long-distance calling song that attracts females from long distances and consists of a long chirp followed by series of short chirps. Once they’ve made contact with a female, they sing a short-range courtship song that is also composed of long and short chirps, but is more variable. Females can accept or reject males at this stage.
• #10: So we already know adult females have functional ears, allowing them to perceive and localize male calling songs. But T. oceanicus undergoes an extended period of development and possesses functioning ears for the last few larval instars. This means they have an opportunity to perceive and assess their social environment prior to actually making mating decisions.
• #11: T. oceanicus females vary in their mating behavior based on social experiences, both during rearing and adulthood. Let’s say this female on top was reared in the presence of calling song, which simulates a social environment full of males. The female on the bottom was reared in silence, simulating a scarcity of mates. If you presence both females with an attractive male song, they beeline for it. But if you present them with an unattractive male song, the female reared in silence beelines, but the female reared in the presence of song is slower to approach.
• #12: Mating experience,
• #17: Call: glm(formula = crickets$ResponseType ~ A_Env * J_Env + crickets$Courtship, family = binomial) Deviance Residuals: Min 1Q Median 3Q Max -1.8391 -1.1502 0.6826 0.9039 1.3569 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) -0.014639 0.296429 -0.049 0.96061 A_Envsong 1.364480 0.428368 3.185 0.00145 ** J_Envsong 0.723738 0.400879 1.805 0.07102 . crickets$Courtship -0.009951 0.009216 -1.080 0.28026 A_Envsong:J_Envsong -0.586167 0.624435 -0.939 0.34788 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 (Dispersion parameter for binomial family taken to be 1) Null deviance: 266.72 on 210 degrees of freedom Residual deviance: 250.15 on 206 degrees of freedom AIC: 260.15 Number of Fisher Scoring iterations: 4
• #18: Anova Table (Type II tests) Response: TimeDiff_s Sum Sq Df F value Pr(>F) A_Env 14905 1 4.1570 0.04566 * J_Env 5225 1 1.4574 0.23186 crickets$Courtship 5371 1 1.4980 0.22554 A_Env:J_Env 39 1 0.0108 0.91748 Residuals 225884 63 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
• #19: Anova Table (Type II tests) Response: crickets$Distance_cm Sum Sq Df F value Pr(>F) A_Env 10178 1 5.1888 0.02428 * J_Env 186 1 0.0948 0.75867 crickets$Courtship 1576 1 0.8033 0.37167 A_Env:J_Env 1039 1 0.5296 0.46800 Residuals 268733 137 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
• #22: The effects of the social environment produce a cool feedback loop: the strength and direction of selection influence the composition of the social environment, which influences female responses to male signals, which then determine what selection on those same signals looks like. For this study, I’m focusing on how the social environment influences individual females’ responses to sexual signals.