The sexual deception of orchids - Anne Gaskett

譯者: Lilian Chiu 審譯者: Helen Chang

The world’s largest orchid grows several meters tall.

世界上最大的蘭花 可以高達數公尺。

The tiniest is practically invisible.

最小的則是小到根本看不見。

Some bloom high up in trees,

有些蘭花在高聳的樹上開花，

while others live underground.

有些則生長在地面上。

All in, there are around 28,000 species of orchid on earth –

總的來說，地球上有 大約兩萬八千種蘭花——

about as many as all the bird, mammal and reptile species combined.

等同於鳥類、哺乳類，及爬蟲類 全部加起來的物種數目。

They grow all over the world,

蘭花在世界各地都會生長，

bearing every imaginable colour, shape, and pattern.

有各種能想像出來的 顏色、形狀、花紋。

And there’s a cunning purpose behind these elaborate displays:

蘭花之所以有如此多樣的呈現， 背後其實有著巧妙的目的：

many orchids trick insects,

許多蘭花會欺騙昆蟲，

sometimes even into having sex with them.

有時甚至騙昆蟲和它們性交。

Like other flowers,

和其他的花一樣， 大部分的蘭花也需要吸引昆蟲

most orchids need to attract insects

to gather their pollen and carry it between plants.

來採集它們的花粉， 在植物間傳播。

But unlike most flowers,

但，和大部分的花不同的是，

which attract a range of pollinators with sweet nectar,

大部分的花會用甜美的花蜜 來吸引多種傳粉昆蟲，

these masters of deception deploy other tactics–

而身為欺騙大師的蘭花 則採用其他戰略——

like pretending to be an insect’s mate,

比如，假扮成昆蟲的配偶，

letting off alluring scents,

釋放出誘惑的氣味，

and mimicking the appearance of other species.

以及模仿其他物種的外表。

One of their most intriguing methods is sexual deception.

蘭花最有趣的手法之一， 就是「性欺騙」。

Through a combination of sexy shapes and pheromones,

透過性感形狀以及費洛蒙的結合，

orchids convince insects to mate with them.

蘭花能說服昆蟲和它們交配。

Take the bee orchid,

以蜂蘭為例，

whose petals look almost exactly like the velvety body of a bee.

它們的花瓣看起來簡直 就像是蜜蜂的絲絨身體。

This disguise is so convincing that male bees land on the orchid

這種偽裝非常有說服力， 會讓雄蜂降落在蘭花上，

and try to have sex with it,

試圖和它交配，

picking up pollen as they go.

在離開時則會把花粉帶走。

Other orchids have evolved contrasting colours and ultraviolet spots–

其他蘭花則已經演化出 對比色以及紫外線斑點——

invisible to humans but irresistible to insects.

人類無法看見它們， 昆蟲卻無法抗拒它們。

Still others have tactile ‘love-handles’

還有其他蘭花具有 觸覺「愛的把手」，

that ensure insects are positioned precisely for pollination.

確保昆蟲會剛好停留在 能取得花粉的位置。

When a male wasp lands on the hammer orchid, for example,

比如，當雄性黃蜂 降落在鐵錘蘭上面時，

his enthusiastic mating motion flips a hinge in the flower,

牠熱情的交配動作， 造成花朵快速擺動，

forcing his body into the pollen.

迫使牠的身體被擺到花粉當中。

At the next flower he visits,

等牠去造訪下一朵蘭花時，

that same hinge pushes his pollen-covered body onto the stigma,

同樣的擺動動作會將牠那 被花粉覆蓋的身體推入柱頭，

fertilizing it.

讓它受精。

Some orchids make such convincing mates

有些蘭花假扮的配偶 太有說服力了，

that insects even ejaculate on them,

甚至會讓昆蟲在花上射精，

wasting valuable sperm.

浪費寶貴的精子。

But the most vital component of sexual deception is scent:

但，性欺騙最重要的要素是氣味：

orchids mimic the precise scent of a single insect species.

蘭花能夠精準模仿 單一種昆蟲物種的氣味。

This is possible because many insects and flowers

這是有可能的，因為許多昆蟲和花

produce simple organic compounds called hydrocarbons,

都會產生簡單的有機化合物， 叫做碳氫化合物，

which form a layer that protects their bodies from drying out.

它會形成一層膜，防止身體乾掉。

The precise blend of compounds in this layer is species-specific.

形成這層膜的精確化合物 混合配方，每個物種皆不同。

Its scent can double as a way for insects to attract potential mates,

昆蟲可以把氣味加倍， 來吸引可能的配偶，

known as a sex pheromone.

也就是一般所知的性費洛蒙。

Over the course of many thousands of years,

在數千年的過程中，

random compound combinations have given some orchid species

隨機的化合物組合， 讓某些種類的蘭花

precisely the same signature scent as particular insect species.

具有和特定昆蟲物種 相同的特殊氣味。

This matching scent allows them to attract male pollinators

氣味吻合，就能讓這些蘭花 吸引到雄性傳粉昆蟲，

who fall over and over again

牠們則會不斷上勾，

for the flowers masquerading as females

被假扮同種雌性昆蟲的 蘭花給欺騙。

of their own species.

Sexual deception isn’t the only trick orchids have up their sleeves.

蘭花的技倆不只有性欺騙而已。

Their oldest scam is mimicking the shapes and colours

它們最古老的詐術 是在形狀和顏色方面，

of other nectar-producing flowers—

模仿其他會產花蜜的花種——

but without the sweet nectar.

只是蘭花沒有甜美的花蜜。

Some orchids also masquerade as places where insects lay their eggs.

有些蘭花也會橋裝成 昆蟲產卵的地方。

One species not only has the colour and appearance of rotting meat;

有一種蘭花，不僅有 腐肉的顏色和外觀；

it emits a scent of decay as well–

它還會釋放出腐敗的味道——

drawing in flies who deposit their eggs on the flower

吸引蒼蠅在花上產卵，

and unwittingly pollinate the plant.

不知不覺中就協助了異花傳粉。

Other orchids look and smell just like the fungi on which certain insects

還有其他蘭花，看起來 和聞起來都像是菌類，

某些昆蟲會在這些菌類上產卵。

lay their eggs.

Where do all these bizarre adaptations come from?

這些怪異的適應變化是打哪來的？

Random genetic mutations in orchids may result in a trait–

隨機基因突變可能是 造成蘭花某種特性的成因——

like a scent or a shape–

比如氣味或形狀——

that, by chance, matches the needs of a single insect species.

且剛好就符合某種昆蟲的需求。

The huge diversity within the insect world also increases the likelihood

昆蟲世界有著非常高的 多樣性，這點也增加了

蘭花和某種獨一無二的觀眾 成功配對的可能性。

that an orchid will find a unique audience.

Able to make more seeds and offspring with the help of its dedicated pollinators,

在傳粉昆蟲很投入的協助之下， 蘭花得以產生更多種子和後代，

the orchid successfully reproduces in isolation,

因而成功地單獨繁殖，

and becomes a new species.

成為新的物種。

But because of their dependence on sometimes just one pollinator species,

但，因為有些時候蘭花 得要仰賴單一種傳粉昆蟲，

orchids are also vulnerable,

它們也很脆弱，

and many quickly go extinct.

很多種蘭花沒多久就絕種了。

Over time, though,

不過，隨著時間，

more orchid species have formed than died out,

新形成的蘭花種類比絕種的還多，

and orchids are some of the most diverse flowering plants.

且蘭花是最多樣化的 開花植物之一。

They have such exuberant and otherworldly shapes

它們有著豐富又另類的形狀，

that they occasionally deceive human senses, too:

因此有時也能夠欺騙人類的感官：

In their petals we see what appear to be tiny, dancing people,

我們會在蘭花的花瓣上看到 似乎是在跳舞的小人形、

monkey’s faces, spiders,

猴子的臉、蜘蛛，

and even birds in flight.

甚至有在飛行的鳥兒。