No link between nymph and adult coloration in shield bugs: weak selection by predators. Issue 1929 (24th June 2020)

• Record Type: Journal Article
• Authors: Medina, Iliana; Vega-Trejo, Regina; Wallenius, Thomas; Esquerré, Damien; León, Constanza; Perez, Daniela M.; Head, Megan L.
• Is Part Of: Proceedings. Volume 287:Issue 1929(2020)
• Publication Date: 2020-06-24
• Subjects: ontogeny -- colour -- warning signals -- avoidance -- antipredator -- aposematism; Biology -- Periodicals; 570.5
• DOI: 10.1098/rspb.2020.1011
• Languages: English
• ISSNs: 0962-8452

Abstract

Abstract : Many organisms use different antipredator strategies throughout their life, but little is known about the reasons or implications of such changes. For years, it has been suggested that selection by predators should favour uniformity in local warning signals. If this is the case, we would expect high resemblance in colour across life stages in aposematic animals where young and adults share similar morphology and habitat. In this study, we used shield bugs (Hemiptera: Pentatomoidea) to test whether colour and colour diversity evolve similarly at different life stages. Since many of these bugs are considered to be aposematic, we also combined multi-species analyses with predation experiments on the cotton harlequin bug to test whether there is evidence of selection for uniformity in colour across life stages. Overall, we show that the diversity of colours used by both life stages is comparable, but adults are more cryptic than nymphs. We also demonstrate that nymphs and adults of the same species do not tend to look alike. Experiments on our model system suggest that predators can generalise among life stages that look different, and exhibit strong neophobia. Altogether, our results show no evidence of selection favouring colour similarity between adults and nymphs in this speciose clade.