But maternal fastidiousness does not come without costs.

Research conducted at USC on striped ground crickets shows that males who are successful in finding mates usually are larger and that females have a mating bias for males of superior genetic quality.

The research was conducted by Timothy Mousseau, biology, and Kenneth M. Fedorka of the University of Georgia, then a doctoral student at USC.

The results of the USC study, published in the May 6 issue of the prestigious journal Nature, are complex.

Although finding a genetically well-equipped father produces quality sons, the reverse is true for female offspring.

"We found that females gain by selecting a high-quality male to produce high-quality offspring who are males, but it comes at a cost to her daughters," Mousseau said. "Our research is about the evolution of maternal effects. Mate choice is a type of maternal effect in many systems."

For females, it's all about passing their genes on to the next generation, ensuring or at least enhancing the fitness of her offspring and the continuation of the species.

"This study is important because it helps us understand how complex behavior can be molded and shaped by natural selection," Mousseau said. "Darwinian natural selection can explain a variety of behaviors."

While female crickets may be attracted to larger body size in males and female peacocks look for males with an abundance of colorful tail feathers, how does this relate to humans?

"In many human societies, females are attracted to resources," Mousseau said. "Women may choose males based on good genes but also the quality of the environment that mate can provide.

"Females are looking for high-quality mates to acquire specific genes for their offspring or resources that the male can provide for the fitness of their offspring."

However, in the cricket kingdom, it's not all doom and gloom when females find lower-quality males.

"They will have high-quality female offspring," Mousseau said. "It's a trade-off."

Mousseau became interested in studying striped ground crickets' reproductive behavior after reading about them in French literature. He discovered that male crickets of this genus, Allonemobius, have an unusual characteristic: a specialized spur on the hind leg. The spur contributes a fluid called heamolymph to the female during mating, which she converts to eggs. Scientists are able to study the spur to determine a male's mating history.

In the end, the scientists concluded, females are looking for high-quality males because the potential payoff is considerably higher.

"A high-quality male can mate with multiple females, ensuring a greater likelihood that the species will continue," Mousseau said. "The payoff for producing a high-quality male is higher, and this is what many females prefer, even given the costs."

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