---
_id: '61024'
abstract:
- lang: eng
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."
article_number: '140'
article_type: original
author:
- first_name: Pamela Heidi
full_name: Douglas, Pamela Heidi
id: '72311'
last_name: Douglas
- first_name: Gottfried
full_name: Hohmann, Gottfried
last_name: Hohmann
- first_name: Róisín
full_name: Murtagh, Róisín
last_name: Murtagh
- first_name: Robyn
full_name: Thiessen-Bock, Robyn
last_name: Thiessen-Bock
- first_name: Tobias
full_name: Deschner, Tobias
last_name: Deschner
citation:
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. BMC Evolutionary Biology. 2016;16(1). doi:10.1186/s12862-016-0691-3'
apa: 'Douglas, P. H., Hohmann, G., Murtagh, R., Thiessen-Bock, R., & Deschner,
T. (2016). Mixed messages: wild female bonobos show high variability in the timing
of ovulation in relation to sexual swelling patterns. BMC Evolutionary Biology,
16(1), Article 140. https://doi.org/10.1186/s12862-016-0691-3'
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={10.1186/s12862-016-0691-3},
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}
}'
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.” BMC Evolutionary
Biology 16, no. 1 (2016). https://doi.org/10.1186/s12862-016-0691-3.'
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,” BMC Evolutionary Biology, vol.
16, no. 1, Art. no. 140, 2016, doi: 10.1186/s12862-016-0691-3.'
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.”
BMC Evolutionary Biology, vol. 16, no. 1, 140, Springer Science and Business
Media LLC, 2016, doi:10.1186/s12862-016-0691-3.'
short: P.H. Douglas, G. Hohmann, R. Murtagh, R. Thiessen-Bock, T. Deschner, BMC
Evolutionary Biology 16 (2016).
date_created: 2025-08-26T19:10:36Z
date_updated: 2025-08-26T19:52:41Z
department:
- _id: '40'
doi: 10.1186/s12862-016-0691-3
extern: '1'
intvolume: ' 16'
issue: '1'
keyword:
- Primate
- Sexual signalling
- Fecundity
- Endocrine analysis
- LC–MS/MS
- Estrogen
- Pan paniscus
- Pregnanediol
- Mate guarding
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0691-3
oa: '1'
publication: BMC Evolutionary Biology
publication_identifier:
issn:
- 1471-2148
publication_status: published
publisher: Springer Science and Business Media LLC
status: public
title: 'Mixed messages: wild female bonobos show high variability in the timing of
ovulation in relation to sexual swelling patterns'
type: journal_article
user_id: '72311'
volume: 16
year: '2016'
...