Evolutionary Ecology

, Volume 24, Issue 4, pp 879–889

The impact of ovulation mode on sperm quantity and quality in mammals

Original Paper

DOI: 10.1007/s10682-009-9344-y

Cite this article as:
Soulsbury, C.D. & Iossa, G. Evol Ecol (2010) 24: 879. doi:10.1007/s10682-009-9344-y


Ovulation generally takes two forms: spontaneous and induced. These two ovulatory modes are predicted to cause different levels of male–male competition due to differences in males’ ability to predict the timing of ovulation of females that use each mode. Ovulation mode has been shown to be correlated with differences in testis size, but it is not known whether ovulation type influences ejaculate traits, specifically sperm quantity (sperm concentration, ejaculate volume, total motile sperm per ejaculate) and/or sperm quality (% sperm motility, % normal sperm). Using a cross-species comparative analysis of 130 mammals, we found that sperm concentration and total motile sperm per ejaculate were significantly greater in spontaneous ovulators. In contrast, ejaculate volume, % sperm motility and % normal sperm were unrelated to ovulation type. These data show that ovulation alters sperm quantity by increasing sperm concentration but not ejaculate volume, and that sperm quality does not vary with ovulation mode.


Intrasexual competitionSpermatozoaSperm competition riskOvulatory

Supplementary material

10682_2009_9344_MOESM1_ESM.doc (448 kb)
(DOC 448 kb)

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.School of Biological SciencesUniversity of BristolBristolUK
  2. 2.British Ecological SocietyLondonUK