In the mating game, some female mites²（螨虫类） are mightier³ than their mates, new research at the University of Michigan and the Russian Academy of Sciences suggests. The evidence comes, in part, from 40 million-year-old mating mites preserved in Baltic amber⁴（琥珀） . In a paper published March 1 in the Biological Journal of the Linnean Society, researchers Pavel Klimov and Ekaterina Sidorchuk describe an extinct mite¹ species in which the traditional sex roles were reversed.

"In this species, it is the female who has partial or complete control of mating," said Klimov, an associate research scientist at the U-M Museum of Zoology⁵. "This is in contrast to the present-day reproductive behavior of many mite species where almost all aspects of copulation are controlled by males."

In mites, as in other animals including humans, the battle of the sexes has been raging throughout evolutionary⁶ history. Each gender⁷ struggles to get the upper hand to assure that their interests are protected. In the case of mites, males benefit from coercing⁸（强迫） females to mate and making sure no other males mate with them. Harassing⁹ reluctant females, guarding females before and after mating and fighting off competing males are typical behaviors.

Females, on the other hand, gain an evolutionary advantage if they have some control over matters of mating. This allows them to choose superior males to mate with, while rejecting losers (who may be, however, extremely adept¹⁰ at coercing females), and it spares them the wear and tear of being subjected to harassment¹¹, guarding and frequent copulation（交配，交尾） .

In the extinct mite species Glaesacarus rhombeus, the male lacks the specialized¹² organs for clinging to females that are seen in many present-day mites. The female, however, has a pad-like projection¹³（投射，突出） on her rear end that allows her to control the clinging. A remarkably¹⁴ preserved copulating pair of mites found in amber gave Klimov and Sidorchuk a glimpse at how the apparatus¹⁵（装置，设备） worked.

Structures found in some living mites also show evidence of female control over mating, Klimov said. "Some lineages（血统，家系） have developed female copulatory tubes that function like a penis."