massive droughts,

大規模的乾旱

changing landscapes.

變化的地景

Successfully adapting to climate change is growing increasingly important.

能成功適應氣候變遷 變得愈來愈重要

For humans, this means using our technological advancement

對人類而言 這意味著用科技進步

to find solutions,

去找答案

like smarter cities and better water management.

例如更智慧化的都市 更好的水資源管理方法

But for some plants and animals,

但是對某些動植物而言

adapting to these global changes involves the most ancient solution of all:

適應這些全球性變化 要用最古老的解決方法：

evolution.

演化

Evolutionary adaptation usually occurs along time scales of thousands

演化適應通常要花上

to hundreds of thousands of years.

數千到數十萬年的時間

But in cases where species are under especially strong selective conditions,

但是如果物種 處在特別強的天擇條件下

like those caused by rapidly changing climates,

如因快速變遷的氣候 引發的狀態

adaptive evolution can happen more quickly.

適應演化可能更快速發生

In recent decades,

最近幾十年

we've seen many plants,

我們看到許多植物

animals,

動物及昆蟲遷移

and insects relocating themselves

改變自己的身體大小

and undergoing changes to their body sizes,

及改變開花或交配時間

and the dates they flower or breed.

但是這些改變易受外界影響

But many of these are plastic,

或僅改變個體的身體性狀 而非遺傳性變化

or nonheritable changes to an individual's physical traits.

而且生物改變自己的 生理機能

And there are limits to how much an organism can change its own physiology

以適應環境的程度有限

to meet environmental requirements.

這就是為什麼科學家要找出 因演化而改變

That's why scientists are seeking examples of evolutionary changes

物種 DNA 密碼的例子 它們是能遺傳的、

coded in species' DNA that are heritable,

維持長久

long-lasting,

且是物種未來生存的關鍵

and may provide a key to their future.

以灰林鴞為例

Take the tawny owl.

如果 30 年前 你走在寒冷的北歐森林

If you were walking through a wintry forest in northern Europe 30 years ago,

你大概會聽到而非看到

chances are you'd have heard, rather than seen,

這種行蹤飄忽的鳥

this elusive bird.

在雪白的背景下

Against the snowy backdrop,

幾乎看不見牠的羽毛

its plumage would have been near impossible to spot.

今天的地景已大不相同

Today, the landscape is vastly different.

1980 年代起

Since the 1980s,

氣候變遷造成降雪顯著減少

climate change has led to significantly less snowfall,

不過你還是很難看到灰林鴞

but you'd still struggle to spot a tawny owl

因為現在牠們是褐色的

because nowadays, they're brown.

褐色羽毛變種是該物種的 顯性基因表型

The brown color variant is the genetically dominant form of plumage in this species,

但是在歷史上

but historically,

隱性淺灰色表型一度稱霸

the recessive pale gray variant triumphed

因為其選擇優勢 幫助這種獵禽融入背景

because of its selective advantage in helping these predators blend in.

然而積雪覆蓋大不如前 降低了偽裝的機會

However, less snow cover reduces opportunities for camouflage,

所以最近 這種灰色表型

so lately, this gray color variant

已經在天擇戰場上敗退

has been losing the battle against natural selection.

另一方面 褐色表型的後代

The offspring of the brown color morphs, on the other hand,

在無積雪的森林占優勢

have an advantage in exposed forests,

所以褐色灰林鴞 今天極為昌盛

so brown tawny owls are flourishing today.

還有幾種物種也在近幾十年

Several other species have undergone

經歷類似的例子 適應氣候變遷

similar climate-change-adaptive genetic changes in recent decades.

豬籠草蚊快速演化

Pitcher plant mosquitoes have rapidly evolved

趁著氣溫愈來愈暖

to take advantage of the warmer temperatures,

在一年中愈來愈晚 進入蟄伏期

entering dormancy later and later in the year.

二點瓢蟲族群

Two spot ladybug populations,

原本為黑色與非黑色 二種表型各占一半

once comprised of equal numbers of melanic and non-melanic morphs,

現在已經變成幾乎全是 非黑色的組合

have now shifted almost entirely to the non-melanic color combination.

科學家認為 這能保護它們不會過熱

Scientists think that keeps them from overheating.

同時駝背大麻哈魚 已經能適應更溫暖的水

Meanwhile, pink salmon have adapted to warmer waters

讓自己在產卵季更早產卵 以保護敏感的卵

by spawning earlier in the season to protect their sensitive eggs.

歐洲野生百里香 產生更多的驅除油

And wild thyme plants in Europe are producing more repellent oils

以保護自己 不為草食動物所食

to protect themselves against the herbivores

此現象在氣候溫暖時 愈來愈普遍

that become more common when it's warm.

這些動植物屬於一群 已知的 20 種物種

These plants and animals belong to a group of about 20 identified species

對快速氣候變遷 有演化適應能力

with evolutionary adaptations to rapid climate change,

包括玳瑁

including snapping turtles,

木蛙

wood frogs,

蓼

knotweed,

銀班弄蝶

and silver spotted skipper butterflies.

然而科學家希望能從 地球上八百七十萬種物種內

However, scientists hope to discover more species evolving

發現更多因應氣候變遷 而產生的物種演化

in response to climate change out of 8.7 million species on the planet.

對地球上驚人和珍貴的 生物多樣性而言

For most of our planet's astounding and precious biodiversity,

演化不是解答

evolution won't be the answer.

許多物種反而必須靠我們

Instead, many of those species will have to rely on us

幫助它們 在不斷變遷的世界生存

to help them survive a changing world

不然就面臨絕種

or face extinction.

好消息是我們已經有方法

The good news is we already have the tools.

地球公民做出決定

Across the planet, we're making on-the-ground decisions

要幫助整個生態系統適應

that will help entire ecosystems adapt.

目前正在找出並保留 緊急氣候避難所

Critical climate refuges are being identified and set aside,

也在進行各式計畫 幫助可移動的物種

and projects are underway to help mobile species

遷移到更合適的氣候區

move to more suitable climates.

現存的公園及保護區 也在做檢查

Existing parks and protected areas are also doing climate change check-ups

幫助野生動植物 對抗氣候變遷

to help their wildlife cope.

幸好這還在掌控下

Fortunately, it's still within our power

我們還能保留大部分 地球上奇妙的生物多樣性

to preserve much of the wondrous biodiversity of this planet,

畢竟這在許多方面 讓我們能永續生存

which, after all, sustains us in so many ways.

翻譯：Regina Chu