Semen Displacement as a Sperm Competition Strategy in Humans by Gordon G. Gallup, Jr. and Rebecca L. Burch

source: Gordon and Rebecca
Abstract: We examine some of the implications of the possibility that the human penis may have evolved to compete with sperm from other males by displacing rival semen from the cervical end of the vagina prior to ejaculation. The semen displacement hypothesis integrates considerable information about genital morphology and human reproductive behavior, and can be used to generate a number of interesting predictions.

... The human penis, with a relatively larger glans and more pronounced coronal ridge than is found in many other primates, may function to displace seminal fluid from rival males in the vagina by forcing it back over/under the glans. During intercourse the effect of repeated thrusting would be to draw out and displace foreign semen away from the cervix. As a consequence, if a female copulated with more than one male within a short period of time this would allow subsequent males to "scoop out" semen deposited by others before ejaculating
really .... I wonder how they did this research ?


  1. semen
  2. penis
  3. evolution
  4. vagina
  5. repeated thrusting
  6. genital
  7. morphology
  8. sperm


Mark de LA says
Father used to say "If it doesn't reach, piss the damned critters up there" 

winnie says
obviously male generated thoughts........too much penis contemplation It probably evolved from all the...... "handy"....... work you guys do!

Mark de LA says

See Also

  1. Thought A new meditation with 85 viewings related by tag "sperm".
  2. Thought Racism is Fluid Just Like Gender, eh? with 30 viewings related by tag "semen".
  3. Thought Changes are comming! with 24 viewings related by tag "evolution".
  4. Thought Evolution & Transformation with 17 viewings related by tag "evolution".
  5. Thought Some Come Here to Sit and Think with 5 viewings related by tag "evolution".
  6. Thought about: the evolution of everything: how new ideas emerge with 3 viewings related by tag "evolution".
  7. Thought Coulter vs Evolution with 2 viewings related by tag "evolution".
  8. Thought Evolution with 2 viewings related by tag "evolution".
  9. Thought Evolution & Involution & Revolution with 0 viewings related by tag "evolution".
  10. Thought Do you want to be a sperm? with 0 viewings related by tag "sperm".
  11. Thought about: Preoccupations: The Paradigm Shift Rate with 0 viewings related by tag "evolution".