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Article: Secret to birds' mating score: speedy sperm. (study of zebra finches suggests sperm velocity and copulation with non-mates influence the rate of fertilization)(Brief Article)
- Article from:
- Science News
- Article date:
- October 7, 1995
- Author:
CopyrightCOPYRIGHT 1995 Science Service, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Many birds mate and rear young with one lifetime partner, yet occasionally enjoy sexual dalliances with other birds. Indeed, individual out-of-wedlock copulations have a higher fertilization rate than single mating efforts at home.
Fertilization is a numbers game, many ornithologists assert. It becomes less likely the fewer sperm a male ejaculates, and males may release fewer sperm per copulation with their mate than with other females.
But a new study suggests that, while quantity is essential to reproduction, speed matters too. "Sperm velocity is icing on the cake," contend Timothy R. Birkhead and his colleagues at the University of Sheffield in England. ...