Ladies take note. Women who bed other women's husbands are no longer the stereotypical lonely skanks who are desperate for love or money, or in need of much male attention. Adulte-resses of today are independent, successful, and beautiful women. Yes it makes life harder on most wives because nobody wants to envision their husband getting along a bit too well with his colleague or best female friend and later ending up in bed with them.

Worse, a wife may never find out. Scientists say mate poaching happens in almost every society on earth; it begins an estimated 10 to 15 percent of all romantic relationships, according to a survey of nearly 17,000 people worldwide by David P. Schmitt, Ph.D., an evolutionary psychologist at Bradley University in Peoria, Illinois.

"From a historical perspective, women compete with each other for the best mates," says David M. Buss, Ph.D., an evolutionary psychologist at the University of Texas and the author of The Evolution of Desire: Strategies of Human Mating. "Mate poaching is an effective strategy because high-quality men are often in scarce supply, so women are in competition for access to them." So why do these women, who are just as good as a married man's wife or better, venture into extramarital affairs? Here are some answers collected from a Women's Health study.