Reproducing lizards modify sex allocation in response to operational sex ratios

Daniel A. Warner, Richard Shine

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)


Sex-allocation theory suggests that selection may favour maternal skewing of offspring sex ratios if the fitness return from producing a son differs from that for producing a daughter. The operational sex ratio (OSR) may provide information about this potential fitness differential. Previous studies have reached conflicting conclusions about whether or not OSR influences sex allocation in viviparous lizards. Our experimental trials with oviparous lizards (Amphibolurus muricatus) showed that OSR influenced offspring sex ratios, but in a direction opposite to that predicted by theory: females kept in male-biased enclosures overproduced sons rather than daughters (i.e. overproduced the more abundant sex). This response may enhance fitness if local OSRs predict survival probabilities of offspring of each sex, rather than the intensity of sexual competition.

Original languageEnglish
Pages (from-to)47-50
Number of pages4
JournalBiology Letters
Issue number1
Publication statusPublished - 2007
Externally publishedYes


  • Amphibolurus muricatus
  • environmental sex determination
  • sex ratio
  • temperature-dependent sex determination


Dive into the research topics of 'Reproducing lizards modify sex allocation in response to operational sex ratios'. Together they form a unique fingerprint.

Cite this