時(shí)差N小時(shí):在企鵝蛋殼上行走

Yael: Today, we're talking penguin eggs.

今天，我們來談下企鵝的蛋。

Don: Why?

為什么?

Y: Penguins lay their eggs on hard surfaces nearcoastlines, or they might dig burrows if the soilpermits. And because they're optimized forswimming rather than walking, it's difficult forpenguins to gather a lot of soft nesting material. See the problem?

企鵝在海岸邊堅(jiān)硬的地表產(chǎn)蛋，如果土地合適，它們也會挖洞。因?yàn)樗鼈兏瞄L游泳而不是走路，對企鵝來說要收集到很多柔軟的筑巢的材料是很難的。明白問題了吧?

D: Hmm! the penguin lifestyle isn't exactlyeggshell-friendly.

企鵝的生活方式對蛋殼來說并不很友好。

Y: And that's not counting the nasty fights penguins can get into over things like space fortheir nests or burrows, and the stones that some species pile up around their nests if they're inthe open.

那還不包括，企鵝為了爭奪筑巢或洞穴領(lǐng)地而發(fā)生的激烈爭斗，而且如果企鵝在開闊地，它們會在巢穴旁堆積石塊。

D: I bet all that hubbub isn't very good for eggs either. So do penguins lose more eggs thanother species?

我打賭所有的吵鬧聲對蛋也是不利的。那企鵝會比其它物種損失更多的蛋嗎?

Y: Actually, according to one study, only 2.6 percent of penguin eggs break from causes otherthan human interference or predators. That rate is similar to the rate in the rest of the birdworld, even including those birds that have cushy nests and never fight near their eggs.

事實(shí)上，根據(jù)一份研究顯示，排除人類的破壞和掠奪者的影響，只有2.6%的企鵝蛋會破裂。這個(gè)機(jī)率和其它鳥類是一樣的，甚至包括那些有舒適的巢穴且從不在蛋附近打架的鳥類。

D: So how do they do it? By producing thicker shells?

那企鵝是怎樣做的?產(chǎn)出更厚的蛋殼?

Y: Yep. Penguin eggshells are fifty percent thicker than expected for their size. But it isn't easyto produce thick egg shells. It requires a lot of calcium, more than female penguins normallyget in their diets.

是的，企鵝蛋殼比估計(jì)的尺寸要厚一般。但是不容易產(chǎn)出厚蛋殼，這需要很多鈣，遠(yuǎn)多于雌性企鵝正常獵食中所獲得的鈣。

D: And they can't just run to the store for a supplement.

而且它們還不能去商店來補(bǔ)充。

Y: Nope. So in the period right before they lay eggs, female penguins eat a lot of mollusks.The clam and mussel shells in their stomachs slowly leach calcium which is then used to formeggshells. Incidentally, thicker shells also help prevent breakage for birds that lay eggs onrocks, and for ostriches and rheas.

不能。所以在企鵝產(chǎn)蛋前，雌企鵝會吃很多軟體動物，胃中的蚌和貝殼類會緩慢 過濾用于形成蛋殼的鈣。順便說一句，厚蛋殼還能避免企鵝在巖石上產(chǎn)蛋時(shí)蛋殼的破損，就像鴕鳥和美洲駝一樣。

D: I always did wonder about those ostriches.

我總是對這些鴕鳥感到驚奇。

burrow n. 洞穴

nasty adj. 險(xiǎn)惡的

hubbub n. 吵鬧聲

supplement n. 增補(bǔ)

mollusk n. 軟體動物

leach v. 過濾