○張軍輝
In the wake of a so called bomb cyclone sweeping the U.S.East Coast,something strange happened:frozen iguana bodies falling out of trees and littering the ground around the suburbs.
Before explaining what`s going on,I’d like to learn a phrase with you.That’s“bomb cyclone”.
To make a huge storm sound more frightening,weatherexpertsgive itan explosive name——bomb cyclone,but nothing will explode at all.
Now let’s talk about the rain of green reptiles.They lie on lawns belly-up quietly,seemingly dead,but most of them likely aren't dead—they're just really,really cold.
Iguanas,like other reptiles,are ectotherms(also known as being"cold-blooded"),meaning the temperature outside strongly influences their body temperatures.When the outside temperature drops,preservation of an ectotherm's body temperature becomes the No.1 priority.Creatures like iguanas and turtles thus conserve energy by slowing their metabolisms and almost entirely stopping moving.
So,don’t worry about the frozen iguanas.Though they don’t move at all,they're still able to breathe.They're still able to do bodily functions,just very slow.As temperatures warm,the iguanas will thaw and eventually start moving again.Usually after a day or two,they'll“come back to life”and we will see them on trees again.
隨著“炸彈氣旋”橫掃美國(guó)東海岸,發(fā)生了一件怪事:凍僵了的鼠鱗蜥像下雨一樣從樹上紛紛墜落,郊區(qū)的地面上隨處可見。
在我們了解究竟發(fā)生了什么之前,還是一起學(xué)習(xí)一個(gè)詞匯“炸彈氣旋”。
所謂的“炸彈氣旋”并不會(huì)發(fā)生爆炸,只不過(guò)是氣象專家為了讓大風(fēng)暴聽起來(lái)更有震撼力而起了一個(gè)嚇人的名字。
現(xiàn)在我們來(lái)聊聊“綠蜥蜴雨”。這些蜥蜴肚皮朝上,靜靜地躺在地面上,一動(dòng)不動(dòng),看起來(lái)跟死了一樣。但它們大多數(shù)并沒(méi)有死,只是受不了寒冷的天氣。鼠鱗蜥,還有其他一些爬行動(dòng)物,屬于冷血?jiǎng)游?,它們的體溫受外部溫度的影響特別大。當(dāng)氣溫降低時(shí),保持自身溫度成了冷血?jiǎng)游锏氖滓蝿?wù)。比如鼠鱗蜥和海龜通過(guò)降低自身的新陳代謝,甚至停止所有運(yùn)動(dòng)來(lái)維持自身能量。
所以,不要為這些凍僵的蜥蜴擔(dān)心。盡管它們一動(dòng)不動(dòng),但是它們?nèi)匀荒軌蚝粑?,身體功能依然正常運(yùn)轉(zhuǎn),不過(guò)是非常慢而已。隨著氣溫上升,這些蜥蜴就會(huì)“解凍”并重新開始活動(dòng)。通常一兩天,它們就會(huì)“死而復(fù)生”,很快我們就又會(huì)在樹上看到它們的身影。
Notes:
iguana鼠鱗蜥
bomb cyclone炸彈氣旋
explode爆炸
reptile爬行動(dòng)物
ectotherm冷血?jiǎng)游?/p>
metabolism新陳代謝
function功能
thaw解凍;融化。