{"volume":16,"abstract":[{"text":"Background: The evolution of primate sexual swellings and their influence on mating strategies have captivated the\r\ninterest of biologists for over a century. Across the primate order, variability in the timing of ovulation with respect to\r\nfemales’ sexual swelling patterns differs greatly. Since sexual swellings typically function as signals of female fecundity,\r\nthe temporal relation between ovulation and sexual swellings can impact the ability of males to pinpoint ovulation\r\nand thereby affect male mating strategies. Here, we used endocrine parameters to detect ovulation and examined the\r\ntemporal relation between the maximum swelling phase (MSP) and ovulation in wild female bonobos (Pan paniscus).\r\nData were collected at the Luikotale field site, Democratic Republic of Congo, spanning 36 months. Observational data\r\nfrom 13 females were used to characterise female swelling cycles (N = 70). Furthermore, we measured urinary oestrone\r\nand pregnanediol using liquid chromatography–tandem mass spectrometry, and used pregnanediol to determine the\r\ntiming of ovulation in 34 cycles (N = 9 females).\r\nResults: We found that the duration of females’ MSP was highly variable, ranging from 1 to 31 days. Timing of ovulation\r\nvaried considerably in relation to the onset of the MSP, resulting in a very low day-specific probability of ovulation and\r\nfecundity across female cycles. Ovulation occurred during the MSP in only 52.9 % of the analysed swelling cycles, and\r\nfemales showed regular sexual swelling patterns in N = 8 swelling cycles where ovulation did not occur. These findings\r\nreveal that sexual swellings of bonobos are less reliable indicators of ovulation compared to other species of primates.\r\nConclusions: Female bonobos show unusual variability in the duration of the MSP and in the timing of ovulation\r\nrelative to the sexual swelling signal. These data are important for understanding the evolution of sexual signals, how\r\nthey influence male and female mating strategies, and how decoupling visual signals of fecundity from the periovulatory\r\nperiod may affect intersexual conflict. By prolonging the period during which males would need to mate guard females\r\nto ascertain paternity, the temporal variability of this signal may constrain mate-guarding efforts by male bonobos.","lang":"eng"}],"year":"2016","language":[{"iso":"eng"}],"type":"journal_article","article_number":"140","_id":"61024","department":[{"_id":"40"}],"publication_status":"published","citation":{"mla":"Douglas, Pamela Heidi, et al. “Mixed Messages: Wild Female Bonobos Show High Variability in the Timing of Ovulation in Relation to Sexual Swelling Patterns.” <i>BMC Evolutionary Biology</i>, vol. 16, no. 1, 140, Springer Science and Business Media LLC, 2016, doi:<a href=\"https://doi.org/10.1186/s12862-016-0691-3\">10.1186/s12862-016-0691-3</a>.","bibtex":"@article{Douglas_Hohmann_Murtagh_Thiessen-Bock_Deschner_2016, title={Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns}, volume={16}, DOI={<a href=\"https://doi.org/10.1186/s12862-016-0691-3\">10.1186/s12862-016-0691-3</a>}, number={1140}, journal={BMC Evolutionary Biology}, publisher={Springer Science and Business Media LLC}, author={Douglas, Pamela Heidi and Hohmann, Gottfried and Murtagh, Róisín and Thiessen-Bock, Robyn and Deschner, Tobias}, year={2016} }","ama":"Douglas PH, Hohmann G, Murtagh R, Thiessen-Bock R, Deschner T. Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns. <i>BMC Evolutionary Biology</i>. 2016;16(1). doi:<a href=\"https://doi.org/10.1186/s12862-016-0691-3\">10.1186/s12862-016-0691-3</a>","apa":"Douglas, P. H., Hohmann, G., Murtagh, R., Thiessen-Bock, R., &#38; Deschner, T. (2016). Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns. <i>BMC Evolutionary Biology</i>, <i>16</i>(1), Article 140. <a href=\"https://doi.org/10.1186/s12862-016-0691-3\">https://doi.org/10.1186/s12862-016-0691-3</a>","chicago":"Douglas, Pamela Heidi, Gottfried Hohmann, Róisín Murtagh, Robyn Thiessen-Bock, and Tobias Deschner. “Mixed Messages: Wild Female Bonobos Show High Variability in the Timing of Ovulation in Relation to Sexual Swelling Patterns.” <i>BMC Evolutionary Biology</i> 16, no. 1 (2016). <a href=\"https://doi.org/10.1186/s12862-016-0691-3\">https://doi.org/10.1186/s12862-016-0691-3</a>.","short":"P.H. Douglas, G. Hohmann, R. Murtagh, R. Thiessen-Bock, T. Deschner, BMC Evolutionary Biology 16 (2016).","ieee":"P. H. Douglas, G. Hohmann, R. Murtagh, R. Thiessen-Bock, and T. Deschner, “Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns,” <i>BMC Evolutionary Biology</i>, vol. 16, no. 1, Art. no. 140, 2016, doi: <a href=\"https://doi.org/10.1186/s12862-016-0691-3\">10.1186/s12862-016-0691-3</a>."},"status":"public","title":"Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns","publication_identifier":{"issn":["1471-2148"]},"publication":"BMC Evolutionary Biology","doi":"10.1186/s12862-016-0691-3","keyword":["Primate","Sexual signalling","Fecundity","Endocrine analysis","LC–MS/MS","Estrogen","Pan paniscus","Pregnanediol","Mate guarding"],"publisher":"Springer Science and Business Media LLC","date_created":"2025-08-26T19:10:36Z","main_file_link":[{"url":"https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0691-3","open_access":"1"}],"oa":"1","user_id":"72311","date_updated":"2025-08-26T19:52:41Z","intvolume":"        16","article_type":"original","issue":"1","extern":"1","author":[{"id":"72311","last_name":"Douglas","full_name":"Douglas, Pamela Heidi","first_name":"Pamela Heidi"},{"first_name":"Gottfried","full_name":"Hohmann, Gottfried","last_name":"Hohmann"},{"first_name":"Róisín","last_name":"Murtagh","full_name":"Murtagh, Róisín"},{"first_name":"Robyn","last_name":"Thiessen-Bock","full_name":"Thiessen-Bock, Robyn"},{"last_name":"Deschner","full_name":"Deschner, Tobias","first_name":"Tobias"}]}