Abstract
Sperm competition is a subconscious force at work during copulation which affects the amount of sperm inseminated and influences the chance of pregnancy. The paper shows that females affect sperm levels through flowback and sperm retention. Males affect sperm levels by inseminating different amounts of sperm due to the time interval between copulatory behavior. The paper examines current theory which states that males subconsciously desire to fertilize a female, while females subconsciously do not want to become pregnant.

Paper Outline:
Abstract
Introduction
Background: Animal Sperm Competition
Experiment #1: Sand Lizards
Experiment #2: Chaffinches
Human Sperm Competition
Experiment #3: Human Females
Experiment #4: Human Males
Works Cited

From the Paper
"One of the aspects of copulatory behavior studied by Baker and Bellis (1993b) was the manipulation of ejaculation by females during in-pair copulation. To do so, they examined the flowback discharged by females after copulation. Flowback comprises vaginal fluid, female tissue, sperm and up to 3ml of seminal fluid (Baker and Bellis, 1993b). Flowback occurs directly after copulation when the female gets up, or most frequently, during the first urination after copulatory behavior. No previous study had been done in regard to the quantity of sperm expelled from possible impregnation by this means."

Tags:monogamous, polygamous, copulatory, menstrual, cycle, vagina