百科知識視頻之煎蛋小學堂17 說說動物圈里的成(luan)雙(jiao)對(pei)

Monogamy-the practice of mating with a single individual for an extended period of time isn't that popular in the animal kingdom.Only about 3% of mammals are monogamous,and,although 95% of birds pair off (at least for one breeding season),paternity tests have revealed that the avian world is chock-full of cheaters.

一夫一妻制 在一段時間內(nèi)只與一個配偶交配，在動物王國內(nèi)并不流行。只有3%的哺乳動物施行一夫一妻制，同時 盡管95%的鳥類在至少一個繁殖季內(nèi)成對出現(xiàn)，親權(quán)鑒定實驗顯示 鳥類世界里盡是偷吃者.

The least loyal bird species might be the superb fairywren: they form lifelong bonds and,if you watched a pair of them from morning til night for an entire breeding season,you'd think they were perfectly faithful.But that's only because female fairywrens cheat under cover of darkness.

最不忠誠鳥要數(shù)壯麗細尾鷯鶯 它們結(jié)伴終生，并且 如果你在整個繁殖季的白天內(nèi)觀察一對鷯鶯，可能會覺得 它們挺忠誠的.但這只是因為鷯鶯在夜幕的遮掩下偷情。

Using radio transmitters to track their movements,Researchers discovered that fertile females make daily,pre-dawn flights to other territories.These trips only last about 15 minutes,but apparently that's more than long enough.DNA tests show that just 25% of baby superb fairywrens are their father's biological offspring.

通過無線電發(fā)射器追蹤其行蹤，研究者發(fā)現(xiàn) 有生育能力的雌性每天黃昏前都會飛到其他地方。時間只有15分鐘 不過顯然夠長了，DNA測試顯示 只有25%的壯麗細尾鷯鶯是其父親真正的后代。

Even though modern genetics might be deflating our romantic notions about lovebirds,from a biological standpoint,pairing up with one individual and then copulating with others on the side makes a lot more sense than absolute sexual loyalty.

即便現(xiàn)代基因?qū)W可能毀了我們對鳥兒赤誠的觀念，從生物學角度而言，與一方結(jié)對但同時與多方交配，比絕對忠誠要有意義的多。

For birds,pairing up is a good strategy because their young require a ton of care,so males increase their chances of successful reproduction if they stick around and lend a beak.On the other hand,putting all of one's eggs in a single basket is a risky proposition,so it also makes sense for males to try and slip some of their genetic material into a few other nests if they can.

對鳥類而言 結(jié)對很有意義 因為幼鳥需要極多的關(guān)照，如果雄性繞在周圍幫幫忙的話 繁衍的成功率更大。另一方面 把蛋都放在一個籃子里很危險，因此雄性在可能的情況下把基因散播到其他巢內(nèi)，也有它的道理，

Females,of course,can't have more than one nest,but they can sneak around with other guys so their eggs have some varieties,Cheating might also help explain the otherwise unexpected physical differences between males and females in apparently monogamous species.We've long had a solid explanation for this kind of male/female dimorphism in explicitly non-monogamous species:because if a male plans to mate with many females,he needs to win their affection and fend off other suitors.

當然雌性只能抱一個窩，但它們可以和其他雄性私交 讓蛋有些多樣性。偷吃可能也可以解釋貌似一夫一妻制物種間，后代與父母間的令人意外的外表差異，我們早就對這種全無一夫一妻制的物種間“夫妻”二者，有了令人信服的解釋。因為 如果雄性打算與其他多個雌性結(jié)對，它就得贏得雌性歡心 同時提防其他適合對象。

Over thousands of generations,the traits that help him successfully mate can become more and more pronounced,even if they serve absolutely no other purpose.For example male gorillas who fight each other for exclusive mating rights with the females in their clan are much larger than female gorillas,while male and female gibbons,which are monogamous,are the same size.

千世萬代后 助其成功結(jié)對的特性，會越來越顯著 即使它們沒有其他任何用處，比如 為了獲得領(lǐng)地內(nèi)與雌性猩猩獨一交配權(quán)而與他者，大打出手的猩猩比雌性大得多，而一夫一妻制的雌性長臂猿大小相近.

Which brings us to our favorite primates,homo sapiens,There are undeniable physical differences between males and females,but it's unclear whether they're pronounced enough to suggest that our ancestors lived in harems like gorillas or whether our differences just stem from a monogamous but adulterous society like the superb fairywren's.

現(xiàn)在該說說我們的最愛 晚期智人了。他們雌雄性間的差異不可忽視，但還不清楚這是否足以證明，我們的祖先和猩猩一樣 后宮三千 抑或是我們的跟植于，鷯鶯般一夫一妻但偷情成性的社會里。

But one thing is clear:among all the species on Earth,monogamy is rare,and monogamy without cheating is rarer.There is,however,at least one known example of perfect,lifelong fidelity,and its name is Diplozoon paradoxum,When two of these young flatworms find each other,they literally fuse together to form what looks like a single organism,and this adultery-free union lasts for their entire long and amorous lives.

但有一點很清楚 地球上所有的生物中，一夫一妻極為少見 不偷吃的一夫一妻更罕見。不過 至少還有一個赤膽忠心的例子，它叫奇異雙身吸蟲。當兩只年輕的吸蟲相遇時，它們可說是融合在一起 形成貌似單一的有機體，這種忠貞的感情在它們漫長的一生內(nèi)絲毫不變。

Which they spend sucking blood from fishgills.A truly romantic attachment!

它們在一起 從魚鰓中吸血，真浪漫的一對啊!