Successful breeding predicts divorce in plovers ; Scientific Reports
When individuals breed more than once, parents are faced with the choice of whether to re-mate with their old partner or divorce and select a new mate. Evolutionary theory predicts that, following successful reproduction with a given partner, that partner should be retained for future reproduction. However, recent work in a polygamous bird, has instead indicated that successful parents divorced more often than failed breeders (Halimubieke et al. in Ecol Evol 9:10734-10745, 2019), because one parent can benefit by mating with a new partner and reproducing shortly after divorce. Here we investigate whether successful breeding predicts divorce using data from 14 well-monitored populations of plovers (Charadrius spp.). We show that successful nesting leads to divorce, whereas nest failure leads to retention of the mate for follow-up breeding. Plovers that divorced their partners and simultaneously deserted their broods produced more offspring within a season than parents that retained their mate. Our work provides a counterpoint to theoretical expectations that divorce is triggered by low reproductive success, and supports adaptive explanations of divorce as a strategy to improve individual reproductive success. In addition, we show that temperature may modulate these costs and benefits, and contribute to dynamic variation in patterns of divorce across plover breeding systems. ; Chinese Scholarship CouncilChina Scholarship Council; Royal Society Wolfson Merit AwardRoyal Society of London [WM170050]; APEX [APX\R1\191045]; Leverhulme TrustLeverhulme Trust [RF/2/RFG/2005/0279, ID200660763]; National Research, Development and Innovation Office of Hungary [ELVONAL KKP-126949, K-116310, NN 125642]; [NBAF547]; [NBAF933]; [NBAF441] ; This work was supported by the Chinese Scholarship Council (to NH). Royal Society Wolfson Merit Award WM170050, APEX APX\R1\191045 and Leverhulme Trust (RF/2/RFG/2005/0279, ID200660763) (to TS). the National Research, Development and Innovation Office of Hungary (ELVONAL KKP-126949, K-116310 (to TS, JOV, VK and NH); NN 125642 (to AK and GCM)). NBAF-Sheffield supported by grants (NBAF547, NBAF933, NBAF441). Other funding sources of fieldworks are provided in the Supplementary acknowledgements. We thank all fieldwork volunteers and people who have helped with data collection. Thanks to Andras Liker, Philippa Harding, Zitan Song, Claire Tanner and Kees Wanders for their advice on previous versions of the manuscript. We also thank Siyu Ding for providing original plover illustrations and the map in Fig. 1. ; Public domain authored by a U.S. government employee