Male crickets increase sperm number in relation to competition and female size

  title={Male crickets increase sperm number in relation to competition and female size},
  author={Alex R. Gage and Christopher J. Barnard},
  journal={Behavioral Ecology and Sociobiology},
Abstract There is evidence to suggest that males of various species can respond to the threat of sperm competition by varying the amount of sperm transferred during copulation. We tested this in two species of cricket, Acheta domesticus and Gryllodes supplicans (Orthoptera: Gryllidae) by varying the apparent threat of intermale competition experimentally. The results showed that males of both species increased the amount of sperm transferred as apparent competition increased and that male A… 

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  • L. SimmonsC. Kvarnemo
  • Biology
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1997
It is shown that under conditions characteristic of courtship role reversal, male expenditure on the spermatophore is dependent on female size, and reduced ejaculate expenditure under increased sperm competition intensity is in accord with theoretical expectation.

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Sperm allocation in relation to male traits, female size, and copulation behaviour in freshwater crayfish species

Results indicate that male freshwater crayfish can modulate their sperm expenditure in accordance with cues that indicate female fecundity, and a novel finding is the decrease in sperm expenditure with male body size, which may suggest that large, old male cray fish are better able than small males to economise sperm at a given mating to perform multiple matings during a reproductive season.




  • S. Sakaluk
  • Biology
    Evolution; international journal of organic evolution
  • 1986
The pattern of sperm predominance in doubly mated female crickets, Gryllodes supplicans, was investigated using a radiation‐sterility technique; evidently, mixing of ejaculates within a female's spermatheca does occur.

Bushcricket spermatophores vary in accord with sperm competition and parental investment theory

It is shown how male Requena verticalis increase the number of sperm in the ampulla of the spermatophore and reduce the amount of sperMatophylax material when mating with females with whom they have a low confidence of paternity.

Ejaculate size varies with socio‐sexual situation in an insect

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Spermatophore size and its role in the reproductive behaviour of the cricket, Gryllodes supplicans (Orthoptera: Gryllidae)

The spermatophore that a male cricket of Gryllodes supplicans transfers to the female during mating, includes a large gelatinous portion (spermatophylax) that is removed and consumed by the female

Risk of sperm competition directly affects ejaculate size in the Mediterranean fruit fly


  • N. Wedell
  • Biology
    Evolution; international journal of organic evolution
  • 1993
Analysis of comparative data of 28 species of bushcrickets reveals that male spermatophore size is positively correlated with female refractory period, which, in turn, correlates with male fertilization success, indicating that the variation in sperMatophore sizes is better explained by a mating‐effort function than a paternal investment function.


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M masturbation is a male strategy to increase sperm fitness without increasing sperm numbers in the female tract as a function of risk of sperm competition; female reproductive value; and optimum partitioning of ejaculates between successive in-pair copulations.

Ejaculate Cost and Male Choice

The problems of limited ejaculatory capacity and male choice merit greater attention in both theory and in empirical research.

Sperm competition in birds : evolutionary causes and consequences

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