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Sperm Recognize "Brothers," Team Up for Speed

• deleted 17y ago
  [deleted]
• steve19 17y ago
  Unless these mice participate mating orgies, this seems to me like a rather useless evolutionary trait.
  • AlisdairO 17y ago
    ...which according to the article, they pretty much do.
  • nathanmarz 17y ago
    On the contrary, sperm competition occurs frequently in many animal species (and more often than you'd think in humans - the stats are quite enlightening). Since this trait increases the chances that your sperm will win and pass on your genes, it is a very useful evolutionary trait. More information: http://en.wikipedia.org/wiki/Sperm_competition http://en.wikipedia.org/wiki/Sperm_competition
    • jules 17y ago
      The length of this competitive “window” might be as short as 2 or 3 days (Gomendio & Rolda´n, 1993) or as long as 7 to 9 days (Smith, 1984). Using an intermediate estimate of 5 days, Baker and Bellis (1995) argued that the questionnaire data they collected on female sexual behavior indicated that 17.5% of British women “double mated” at some point during the first 50 copulations in their lifetimes. http://www.toddkshackelford.com/downloads/Shackelford-Pound-Goetz-RGP-2005.pdf http://www.toddkshackelford.com/downloads/Shackelford-Pound-...
• crazydiamond 17y ago
  (supposedly) In humans, the penis is designed to pull out previously ejaculated sperm, so only one's own is left inside.
  • deleted 17y ago
    [deleted]
  • zackattack 17y ago
    In many animals actually, this is widely believed in ethology