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Abstract Temperature influences the expression of a wide range of behavioral traits in ectotherms, including many involved in the initiation of pair formation and mating. Although opportunities to mate are thought to be greatest when male and female activity overlap, sex‐specific behaviors and physiology could result in mismatched thermal optima for male and female courtship. Here, we investigate how conflicts in the thermal sensitivity of male and female courtship activity affect patterns of mating across temperatures inEnchenopa binotatatreehoppers (Hemiptera: Membracidae). These plant‐feeding insects coordinate mating with plant‐borne vibrational signals exchanged in male–female duets prior to pair formation. We manipulated temperature across an ecologically relevant range (18–36ºC) and tested the likelihood of individual male and femaleE. binotatato engage in courtship activity using vibrational playbacks. We then staged male–female mating interactions across the same temperature range and quantified the thermal sensitivity of mating‐related behaviors across stages of mating. Specifically, we measured the timing of duetting, the likelihood for key pre‐copulatory behaviors to occur, whether the pair mated, and copulation duration. We found sex‐specific thermal sensitivity in courtship activity: Males showed a clear peak of activity at intermediate temperatures (27–30ºC), while females showed highest activity at the hotter thermal extreme. Mating rates, courtship duets, and copulatory attempts were less likely to occur at thermal extremes. Also, duetting occurred earlier and copulation was shortest at higher temperatures. Overall, our data suggest that sexes differ in how temperature affects mating‐related activity and some processes involved in mate coordination may be more sensitive than others across variable thermal environments.
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Harvesters (Arachnida: Opiliones) mate more at cooler temperatures, but the effect of temperature on mating varies across years
Abstract Temperature impacts a wide range of mating behaviors, particularly in ectothermic organisms that tend to have body temperatures similar to ambient thermal conditions. Here, we test the effects of thermal variation on precopulatory and copulatory behavior in the harvesterLeiobunum politumWeed 1889, which belongs to the group commonly known as daddy longlegs. We ran single choice mating trials across temperatures commonly experienced in the field during the mating season (18–34°C) for 2 years. We tested how temperature affected the likelihood to move, attempt to mate, and successfully mate, as well as the duration of copulation. Mating was highest at low to intermediate temperatures, and the temperature at which peak mating rates occurred varied across years. The wide range of temperatures across whichL. politumis found to mate reflects thermal variability in the field and the flexibility in mating behavior in this fascinating animal.
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- Award ID(s):
- 1656818
- PAR ID:
- 10396760
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ethology
- Volume:
- 128
- Issue:
- 7
- ISSN:
- 0179-1613
- Page Range / eLocation ID:
- p. 522-529
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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