時(shí)差N小時(shí):藍(lán)鯨是天生的歌唱家(下)

Wow! That is nearly ten times greater than thedifference observed in the whales. Pretty amazing,right? But, why are they such pitch perfectionists?Well, one hypothesis has to do with the Dopplershift. Really? You mean the acoustic effect thatmakes the pitch of an ambulance siren sound asthough it’s higher as the ambulance approaches andlower after it passes you. Exactly. Since the whale’spitch is so accurate, they hypothesize that otherwhales may be able to locate an individual bylistening for a slight shift in pitch that would becaused by the Doppler effect as the two whales move towards or away from each other. That'samazing. Hey,I wonder if any blue whales offer singing lessons.

哇!那比觀察到的鯨魚中的差距要大10倍。很令人驚訝，對(duì)吧?但是為什么它們能發(fā)出如此完美的聲音嗎?一種猜想是與多普勒頻移有關(guān)。真的嗎?你是說聲學(xué)效應(yīng)使救護(hù)車臨近時(shí)鳴笛聲更響亮，而當(dāng)它經(jīng)過你時(shí)，聲音會(huì)變?nèi)?。正是。因?yàn)樗{(lán)鯨的音高非常精準(zhǔn)，當(dāng)2只藍(lán)鯨彼此游近或遠(yuǎn)離時(shí)，它們傾聽由多普勒頻移引起的音高中的微弱變化，就能推定其它藍(lán)鯨的位置。那真令人驚奇。嘿，我在想是否有藍(lán)鯨教唱歌的課。

詞語注釋：

Doppler shift 多普勒頻移