Exaggerated mandibles are correlated with enhanced foraging efficacy in male Auckland tree w ētā

Biol Lett. 2023 Nov;19(11):20230207. doi: 10.1098/rsbl.2023.0207. Epub 2023 Nov 15.ABSTRACTSexual selection has driven the evolution of weaponry for males to fight rivals to gain access to females. Although weapons are predicted to increase males' reproductive success, they are also expected to incur costs and may impair functional activities, including foraging. Using feeding assays, we tested whether the enlarged mandibles of Auckland tree wētā (Hemideina thoracica) impact feeding activity (the total volume of biomass consumed, bite rate, and number of foraging visits) and foraging behaviour (time spent moving, feeding, or stationary). We predicted that increased head capsule size in male wētā would hinder their foraging efficacy. However, we found that wētā with longer heads fed at a faster rate and spent less time foraging than wētā with smaller heads, regardless of sex. Contrary to expectations that weapons impede functional activities, our results demonstrate that exaggerated traits can improve feeding performance and may offer benefits other than increased mating success.PMID:37964578 | PMC:PMC10646448 | DOI:10.1098/rsbl.2023.0207

Source: Biology Letters - November 15, 2023 Category: Biology Authors: Bridgette Farnworth Samuel Purdie Priscilla M Wehi Christina J Painting Source Type: research