How long is a giant sperm?

  title={How long is a giant sperm?},
  author={Scott Pitnick and Greg Spicer and Therese Ann Markow},

Sperm morphology and function in passerine birds : insights from intra-and interspecific studies by

............................................................................................................................... 2 General introduction

Oxidative stress in sperm competition games: Experimental tests of the soma vs. germline allocation trade-off in wild House Sparrows Passer domesticus

It is found that ejaculate quality correlates with OS level in sperm, while dominant males produce more oxidized and lower quality ejaculates, which highlights OS and strategic antioxidant allocation as the proximate physiological mechanism underlying ejaculatequality and male reproductive tactics.

Structural specialties, curiosities, and record‐breaking features of crustacean reproduction

  • G. Vogt
  • Biology
    Journal of morphology
  • 2016
These examples from a single invertebrate subphylum and a single life history aspect illustrate that morphological solutions to functional requirements can be as spectacular as behavioral adaptations.

Gender based disruptive selection maintains body size polymorphism in Drosophila melanogaster

Results clearly show that selection on body size operates in the opposite direction (disruptive selection) for the two genders, thus explaining the persistence of size polymorphisms in the holometabolous insect, Drosophila melanogaster.

Sperm competition and the evolution of spermatogenesis.

It is argued that sperm competition has been an important selection pressure acting on multiple aspects of spermatogenesis, causing variation in the number and morphology of sperm produced, and in the molecular and cellular processes by which this happens.

Food Restriction and Sperm Number in the Water Strider Aquarius remigis.

It is found that males and females in natural populations often contain few or no sperm, and the fitness of both sexes may, at times, be limited by sperm supplies, with food restriction having a drastic effect on sperm numbers in wild males.

Structure and ultrastructure of spermatozoa and spermiogenesis in three species of Lucilia Robineau‐desvoidy, 1830 (Diptera: Calliphoridae)

The male internal reproductive tract consists of testis, deferent ducts, a strongly developed seminal vesicle, accessory glands, and ejaculatory duct, consistent with the structural diversity of the dipteran reproductive tract and spermatozoa, comprising an essential tool for understanding the complex variations found in the Diptera.

Modelling the evolution and consequences of mate choice

Overall, mate choice is shown to be an important evolutionary force, with wide-ranging ramifications across diverse taxa, and e�ects so varied as to include the evolution of sex, the genetic variation in species, speciation, and post-copulatory behaviour, amongst others.

Intraspecific variation in sperm length in two passerine species, the Bluethroat Luscinia svecica and the Willow Warbler Phylloscopus trochilus

Laskemoen, T., Natural History Museum, University of Oslo, P.O. Box 1172 Blindern,NO-0318 Oslo, Norway. (* Corresponding author)Kleven, O., Natural History Museum,



Male Gametic Strategies: Sperm Size, Testes Size, and the Allocation of Ejaculate Among Successive Mates by the Sperm-Limited Fly Drosophila pachea and Its Relatives

Hypotheses to explain the maintenance of male ejaculate delivery patterns that are consistent with sperm competition and bet-hedging theory are examined, as are potential selection pressures responsible for sperm-size evolution.

Large-male advantages associated with costs of sperm production in Drosophila hydei, a species with giant sperm.

  • S. PitnickT. Markow
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1994
Smaller males of the fruit fly Drosophila hydei were found to make a greater relative investment in testicular tissue growth, even though they have shorter and thinner testes, and correlations should exist between male body size, rates of sperm production, and fitness attributes associated with the production of sperm.

Another way of being anisogamous in Drosophila subgenus species: giant sperm, one-to-one gamete ratio, and high zygote provisioning.

It is proposed that virtually every giant sperm constitutes a "direct paternal legacy to the embryo," which, in contrast to any male-derived nuptial gift, cannot be minimized by female remating.