And there may be even more complicated reasons for preferring one sex of offspring to the other.
You receive one sex chromosome from your mother and another from your father.
In the future, Persons and his colleagues want to see if such tails were typically found in one sex or the other.
This is really no surprise at all in a mammalian species where one sex does all the viviparous part of the perpetuation of it.
In recent years, a few state school athletic associations, such as Washington, Oregon, Illinois and Colorado, have approved allowing students who physically are one sex but identify as another to compete on teams of the sex with which they identify.
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One of the sex scandals torpedoed his expected run for the French presidency this year.
One animal whose sex life has come in for close scrutiny is the wombat.
Alternatively the Court could decide that there is no standing for private citizens to defend the California law, since the state of California declined to do so, and leave the one same-sex couple free to marry but not allow the case to serve as a precedent.
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One aim of the Sex Discrimination Act (1975) was to challenge stereotypes.
One in four men and one in six women said they now used condoms consistently during sex compared with less than one in five men and one in seven women in 1990's survey.
Specifically, Leahy had proposed recognizing same-sex marriages in which one spouse is an American, and allowing U.S. citizens to sponsor foreign-born same-sex partners for green cards given proof of a committed relationship.
The survey calls for more sex education for adults, given that about one in five participants said they had never had sex education in school.
Passing legislation to allow same-sex marriage was one of Hollande's election pledges in campaigning last year.
Most people have 46 chromosomes occurring in 22 pairs, plus two sex chromosomes, one maternal and one paternal.
Graham, too, has appointments on the side, and, undeservedly, he is the one character who gets sexy sex scenes.
Extending the right to marry and adopt to same-sex couples was one of President Francois Hollande's electoral pledges in campaigning this year.
Extending the right to marry and adopt to same-sex couples was one of President Francois Hollande's electoral pledges in campaigning last year.
And of the 38 states that have banned same-sex marriage in one way or another, 24 were carried by Republican nominee Mitt Romney in the 2012 presidential contest.
He also also finds himself being labelled a sex symbol with one American magazine even voting him - 'one of the 30 most interesting people in the world'.
As more states legalize same-sex marriage, one of the key questions the justices may be forced to address is whether a national consensus now exists supporting the idea of expanding a "marriage equality" right to homosexuals.
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They were compared with 84 same-sex couples in their friendship circle who didn't get civil unions, and with 55 heterosexual married couples in which one of the spouses was a sibling of one of the same-sex couples in a civil union.
Mr Peckham also pointed out that two single-sex toilets - one for boys and one for girls - would need one man and one woman to supervise them, whereas the unisex facilities would only need supervision by one member of staff of either gender.
With the mix of laws on the books in this country, simply crossing a state border from a state that recognizes the marriage of a same-sex couple to one that doesn't can mean the step- and adoptive-parents can suddenly become legal strangers to them.
Portugal had five divorces of same-sex couples in 2011, for example, while Ireland has had one application for dissolution of a same-sex civil partnership since such unions became available at the start of 2011.
He was one of the crucial, last-minute votes in favor of same-sex marriage in 2011, and the only one of four Republican state senators who supported that bill to remain in office.
Forty-one states now forbid same-sex marriage, although nine of them allow civil partnerships.
McQueen is nominated for best director, while his film, about a man battling sex addiction, is one of six up for best film.
And then comes a green double-decker bus which lists its destination as "nowhere" - just like the one on the sleeve for The Sex Pistols' Pretty Vacant.
In 1997, Mr. Cooper defended Hawaii in the state's Supreme Court for not performing same-sex marriages, in one of the first major cases tied to the issue.
Participants of this study were shown pictures of 3 individuals of the opposite sex and asked which one would they prefer to go out on a date with.
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