Why do women cry? Because they feel sad, obviously。

But that might not be the only reason, according to a new study. It suggests that women's tears contain chemicals that send men a powerful if unspoken message:

Sex? Now? Fugeddaboudit。

Scientists at Israel's Weizmann Insitute had men sniff the tears of women who had cried while watching sad movies. As the men sniffed, they watched images of the women on a computer screen。

What happened? The tears didn't make the men sad. They didn't make them more empathetic. But they did make the women's faces less sexually appealing to the men。

And when the researchers tested the men's blood, they found that the "chemosignals" in women's tears triggered a steep decline in testosterone, a hormone that is related to sexual arousal。

What does it all mean? The findings seem to raise more questions than they answered。

"What is the chemical involved?" study scientist Noam Sobel, a professor of neurobiology at the institute, asked in a written statement. "Do different kinds of emotional situations send different tear-encoded signals?"

Sobel doesn't think women are the only ones whose tears send signals。

"We don't think there is something special about women's tears," he said. "We definitely predict chemical signals in men's tears and children's tears too."

The study was published in the journal "Science."

一项新的研究表明，女人的眼泪会降低男人的性欲望。

以色列魏兹曼研究所的科学家们发现，女人的眼泪中含有一种“化学信号”，它是降低男同胞性欲的罪魁祸首。

Noam Sobel教授在“BBC服务世界”电台上说，这种信号能够减少睾丸激素和减低大脑对性的兴奋。

他的研究小组现在正计划研究男人的眼泪对女人和男人的作用。

睾丸激素

研究人员收集了女性自愿者在看悲伤电影时的淌下的眼泪。

将眼泪和盐分的溶液放在垫子上，让男性志愿者用鼻子闻吸，当然，他们并不知道自己闻的是眼泪还是盐分，并且让他们边闻边看一些女性的面部照片，并对之做评价。然后，再做一次相同的实验，不过让第一次闻眼泪的男同胞闻吸盐分溶液，让第一次闻盐分的男同胞闻吸眼泪溶液。

研究人员发现，女性照片对闻吸眼泪者的性吸引力比闻吸盐分溶液者要小。

在闻吸了眼泪溶液的男性志愿者的唾液中，睾丸激素-一种能激发性兴奋的荷尔蒙激素-平均降低了13%，但是闻吸了盐分溶液的却不变。

并且通过测量，闻吸眼泪者的皮肤温度、心率、呼吸也下降了。

另外，通过核磁共振成像，在闻吸眼泪者的大脑中，性感知部位活跃程度降低。

研究人员称，眼泪是无味的，男性志愿者并不能区别他们闻的是眼泪还是盐分。

“这项研究证实了一种观点：人类自身的化学信号--即便是那些我们还没有搞清楚的--影响这其他人的行为”，Sobel教授在《科学快讯》的在线杂志上如是评论到。

另外，他还说，这项研究的结果引发了很多问题，比如发出这种信号的化学物是什么。