【英语时差8,16】召唤所有鳄鱼蛋

Ya?l: Hey Don, what's round and white and goes "Cheep!"?

Don: Uhm, I don't know, Ya?l. A ping-pong ball on sale?

Y: Nice guess, but the answer is a crocodile egg.

D: Crocodile eggs "cheep"?

Y: Yep! Crocodiles call from inside their eggs shortly before they hatch.

D: Why?

Y: Biologists in France studied crocodiles in zoos hoping to answer that very question. One hypothesis for the behavior is that the calls may coordinate¹ hatching time for the nest. Essentially² one baby starts to call, meaning "I'm ready to hatch!" and her siblings³ inside their eggs call back to say "OK! Me too!" so the whole brood hatches at the same time.

Another theory is that the calls signal the mother. Crocodiles lay their eggs in the ground and cover them with a mound⁴ of sand. Then she'll stick around and protect the nest until the eggs hatch. At hatching time, the mothers dig open the nest to help the young reach the surface.

However, when females lay eggs in the zoo, zookeepers sneak⁵ in and remove the eggs to hatch them in an incubator. Since the mom crocodile doesn't know the eggs are gone, she continues to stand guard, and the biologists can test her responses to the egg calls.

They played recorded egg calls from a speaker buried in the sand mound. The mother crocodile immediately started to dig up the mound above the speaker. Then they played calls to the incubating eggs. When the eggs heard the recorded  calls, they started to call back and began hatching out of their leathery shells.

D: So both hypotheses may be true. The calls could signal both to the mother and to  other eggs. Pretty nifty!  

1 coordinate   

adj.同等的，协调的；n.同等者；vt.协作，协调

参考例句：

• You must coordinate what you said with what you did.你必须使你的言行一致。
• Maybe we can coordinate the relation of them.或许我们可以调和他们之间的关系。

2 essentially   

adv.本质上，实质上，基本上

参考例句：

• Really great men are essentially modest.真正的伟人大都很谦虚。
• She is an essentially selfish person.她本质上是个自私自利的人。

3 siblings   

n.兄弟，姐妹( sibling的名词复数 )

参考例句：

• A triplet sleeps amongst its two siblings. 一个三胞胎睡在其两个同胞之间。 来自《简明英汉词典》
• She has no way of tracking the donor or her half-siblings down. 她没办法找到那个捐精者或她的兄弟姐妹。 来自时文部分

4 mound   

n.土墩，堤，小山；v.筑堤，用土堆防卫

参考例句：

• The explorers climbed a mound to survey the land around them.勘探者爬上土丘去勘测周围的土地。
• The mound can be used as our screen.这个土丘可做我们的掩蔽物。

5 sneak   

vt.潜行(隐藏,填石缝)；偷偷摸摸做；n.潜行；adj.暗中进行

参考例句：

• He raised his spear and sneak forward.他提起长矛悄悄地前进。
• I saw him sneak away from us.我看见他悄悄地从我们身边走开。