Harvesters (Arachnida: Opiliones) mate more at cooler temperatures, but the effect of temperature on mating varies across years

Abstract

AbstractTemperature 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 harvester Leiobunum politum Weed 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 which L. politum is found to mate reflects thermal variability in the field and the flexibility in mating behavior in this fascinating animal.