美国科学家日前发现了雄狮性感的秘密，那些鬃毛浓密的雄狮比起毛发稀疏的雄狮来，前者更能讨得异性的欢心。

    据美国《生活科学》4月12日报道，美国科学家对该国北部及南部一些动物园中的狮子进行了研究。他们在测量了雄狮鬃毛的长度和浓密程度后发现，生活在较冷环境中的雄狮往往拥有更为健康的鬃毛，而这也是雄狮吸引异性的关键所在。

    温度决定鬃毛质量

    此前，科学家们已经确定，营养、社会因素和遗传因素对雄狮鬃毛的质量起着非常重要的作用。现在，新的发现又指出，温度同样也是影响雄狮鬃毛质量的重要因素，其长度和密度有一半要取决于温度条件。

    在炎热干燥的气候中，雄狮厚厚的鬃毛不利于散热，就像戴了一顶毛皮帽子或是围了一条围巾一样，这可能会导致它们体温过高。研究中所涉及到的从美国伊利诺伊州到得克萨斯州各大动物园的平均温度为：1月份从20华氏度到54华氏度不等；7月份从65华氏度到87华氏度不等。研究人员发现，所有雄狮在其前额、鬓角、肩部和颈部周围都有完整的鬃毛，但南方动物园中的狮子则在诸如肘部、腹部和后背等其他部位没有毛发，北方动物园中的狮子却不是这样。

    雄狮也有“南北差异”

    此项研究的负责人、美国菲尔德博物馆的布鲁斯·帕特森表示，我们在距离狮子20码到30码的地方观察并评价它们，它们相互间评价的距离也是如此。我们发现，在肘部、肋部、后背、腹部、腰部等部位，只有北部动物园中的雄狮长有浓密的毛发。

    研究人员拍到的这些狮子的照片可以很好地说明上述问题。北部动物园里的狮子，比如一只来自伊利诺伊州的雄狮和一只来自圣路易斯的雄狮，它们都长有非常性感的鬃毛。它们的半个后背，两只前腿甚至连它们的肚子上都长满了厚厚的毛。生活在南部动物园里的狮子则与此截然相反。一只来自休斯顿的雄狮和一直来自得克萨斯泰勒城的雄狮的毛发看起来要比生活在北方的狮子稀疏很多，而且它们的背部和腹部都没有毛。

    报道说，雄狮鬃毛的质量会同时向其他雄狮或者雌狮传达某种信息。长而浓密的鬃毛会告诉其他同性“离我远一点”，但它向雌性传达的信息则是“到这儿来”。

    为性感鬃毛付出代价

    千万别以为雄狮这一身性感的鬃毛带来的全是好处，要知道拥有一身性感鬃毛也是需要付出代价的。又长又密的鬃毛会向猎物泄露雄狮所处的位置，会让它们很难在矮树丛中自由穿梭，同时也更容易孳生寄生虫。更主要的是，雄狮为了维持这身漂亮的毛发，需要吃更多的食物以获得所需要的能量，而这就是为什么圈养的狮子通常会拥有更漂亮鬃毛的原因。

    与野生狮子不同，圈养的狮子不需要通过争斗的方式来获取食物。当一只野生雄狮在争斗中失败，那么它的“阳刚之气”就会大打折扣，其体内睾丸激素的水平也会相应随之下降，而这也会使它的鬃毛变得稀疏。帕特森对此表示，（野生狮子）不得不为了保护自己的领地而战斗，因此它们的鬃毛便没有（圈养狮子）那么浓密。

    目前，在诸如肯尼亚察沃国家公园等地，雌性狮子在挑选配偶时，仍然会钟情于那些鬃毛浓密的雄狮。科学家表示，雄狮鬃毛的长度和浓密程度并非物竞天泽的结果，而取决于它们的生活环境。报道说，这项研究的具体内容被发表在新一期的美国《哺乳动物学杂志》上。

    （国际在线独家资讯 王高山）

    Given the choice, a female lion is more likely to be attracted to a shaggy male from Chicago than a well-groomed guy from Houston.

    Chicago lions simply got more game.

    Scientists measured the size and fullness of lions' manes in northern and southern zoos and found that cats living in colder climates had heartier hairstyles, a key attractant to female lions.

    Nutrition, social factors, and genetics have previously been considered important factors affecting mane quality, but the new finding suggests that up to one-half of the mane's length and density is determined by temperature.

    The study is detailed in the April 13 issue of the Journal of Mammalogy.

    Keep it cool

    A thick mane retains heat in a hot, dry climate—like wearing a fur hat or wool scarf—and can cause a big cat to overheat.

    Average temperatures in the parks that were studied— spanning 2,000 miles from Illinois to Texas —varied from 20 to 54 degrees Fahrenheit in January and 65 to 87 degrees in July.

    While all the lions had full manes around the forehead, sideburns, shoulders, and throat, occupants of southern zoos lack hair in other areas, such as the elbows, belly, ribs, and back.

    "We evaluated lions on the same spatial scale that females and males evaluate them, which is from 20 to 30 yards away," said study leader Bruce Patterson of The Field Museum. "The elbows, ribs, back, belly, flanks—those are areas that you only see thick in northern zoos."

    Two southern lions, one from Houston and another from Tyler, Texas, both sport impressive manes, the judges say. But their hair looks thinner than the northern lions and they're hairless on the back and belly.

    Price to pay

    The quality of a male's mane broadcasts information to both sexes. A large, thick mane tells the other guys to "stay away," and says "come hither" to the girls.

    But a sexy mane has its price. It gives away location to prey, makes it difficult to move through bushes, and can harbor parasites.

    Mostly it takes a lot of energy from food to grow and maintain, which is why captive lions generally sport more impressive manes. Zoo lions eat about six meals of 5 to 10 pounds of meat a week, the feline equivalent of three square meals a day.

    Unlike wild lions, captive lions don't have to fight for their food. After losing a fight, a wild lion feels less manly and his testosterone levels drop, which thins out his mane.

    "[Wild lions] have to fight territorial battles and won't have the studly manes that [captive] guys do," Patterson told LiveScience.