Since only one female usually lays eggs in a given larva, it would pay her to produce one male only, because this one male could fertilize all his sisters on emergence.

因为通常只有一只雌性在一个特定的幼虫中产卵，所以它只会产生一只雄性，因为这只雄性可以在孵化时使它所有的姐妹受精。

youdao

There have been female governors, secretaries of state and Supreme Court justices, but only one female speaker.

曾经有过女性州长、国务卿和最高法院大法官，但是女性众议院议长只有一位。

youdao

One female panda usually has only one baby, and it is not easy for wild pandas to have twins anyway.

一只雌性熊猫通常只有一个孩子，而且野生熊猫要生双胞胎也不容易。

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"I think the one story that inspired this book was meeting a wonderful man called Don Mertin in New Zealand and he explaining to me how he had saved a species of bird called a Black Robin when there were just seven individuals left in the world of which only two were female and only one of whom was fertile."

VOA: special.2009.11.18

The dean at the Yale School of Management, Sharon Oster, one of only five female deans at Forbes' top 40 schools, includes a sense of humor as one of the qualities essential for leadership.

FORBES: Magazine Article

There was only one female listed this year: Indra Nooyi of PepsiCo.

FORBES: Magazine Article

The Russian-born Sharapova who moved to Florida at age 7 is one of the only female players that resonates with the U.S. public.

FORBES: Maria Sharapova: Tennis's "It" Girl Once Again