英語聽力文摘 紳士的蝴蝶
One thinks of nature as “red in tooth and claw,” as the old saying goes. Species compete with each other for resources, and members of the same species compete with each other for mates. There’s a lot of scratching and biting going on. Unless you’re a butterfly.
People love butterflies for their gentleness. And according to new studies, that soft, fluttery quality persists all the way down to butterfly battles. Yes, male butterflies compete for the attentions of female butterflies. In fact, some males compete by fluttering.
Researcher Darrel Kemp, who is now at Arizona State University in Tempe, worked on an Australian butterfly called Hypolimnas bolina.
As is the case with many species, the male Hypolimnas bolinas seek to mate with as many females as possible, but the females only mate once. That means at any given time the vast majority of females aren’t in a sexually accommodating state, and the males have to duke it out for the few who are.
How do they battle? Locking horns? Beating their chests? No. They flutter around in a circle. The two competing males never even come in contact, but at a certain point one of them accepts defeat and sails away; while to the victor belongs to the spoiler’s.
What decides winner and loser in a butterfly battle? It isn’t clear yet. Kemp has studied all kind of parameters, from body size to wing spread.
The only consistent factor he found was age. Older butterflies–by old we mean almost three months–win out over younger ones. Maybe the kids just don’t have what it takes for a hard-core flutter-off.
有人認為正如一句古話，自然界充斥著腥牙血爪。同類相互爭奪以求配偶;異類為了資源而劍拔弩張。不斷上演著廝殺，除非，你是蝴蝶。
人們喜歡蝴蝶的彬彬有禮。據(jù)新研究表示，正是溫順悸動的特性讓蝴蝶們遠離爭斗。的確，雄性蝴蝶為了吸引雌性同類會互相競爭。但是，競爭的方式僅僅是抖動翅膀。
研究人員Darrel Kemp在坦佩亞利桑那州立大學研究澳大利亞蝴蝶幻紫斑蛺蝶。
幻紫斑蛺蝶很有代表性，雄性蝶可以任意和雌性蝶交配，但是，雌性蝶一生僅一次。這意味著雌性蝴蝶不得不通過爭斗來求得配偶權(quán)。
他們?nèi)绾螤幎纺?斗角?捶胸?都不對，他們只是在一個圈內(nèi)拍打翅膀。兩只雄性蝴蝶居然沒有任何身體觸碰，但是在某個時間已經(jīng)決出勝負，而敗者就自動離開。
決定輸贏的因素還不是很清楚，Kemp參考了各項參數(shù)，從蝴蝶體型到翼展。
一個共同的因素在于年齡。年老的蝴蝶(超過三個月)通常會取勝，也許姜還是老的辣吧!
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