荷蘭瓦赫寧根大學(xué)的研究表明一只寄生蜂能夠?qū)W習(xí)識別一種由交配過的（或受精的）大菜粉蝶（Pieris brassicae）分泌的氣味,。這一現(xiàn)象發(fā)生在它們從其寄居的菜粉蝶身上爬去一株這只蝴蝶剛產(chǎn)完卵的宿主植物的期間,，一天后，這只寄生蜂就能按相同線路飛行,。沒有此類經(jīng)歷的寄生蜂就不能將交配過的蝴蝶和未受精的蝴蝶區(qū)分開,。研究員用實驗證明長期記憶的產(chǎn)生就是用于記住這種氣味。
在交配過程中,，雄性大菜粉蝶將一種叫做氰化苯的特別氣味傳輸?shù)狡渑渑俭w內(nèi),。這種氣味能阻擊雄性情敵。只需一分鐘（僅僅0.5分的時間）甘藍夜蛾赤眼寄居蜂就能利用菜粉蝶的性攻擊氣味,，它們擁有這與生俱來的本領(lǐng),。沒有經(jīng)驗的寄生蜂發(fā)現(xiàn)并利用性攻擊氣味來識別交配過的菜粉蝶，然后寄居在它們身上,。當這些蝴蝶將它們的卵產(chǎn)在白菜上時,，寄居蜂從菜粉蝶身上爬下來將它自己的卵產(chǎn)在蝴蝶剛產(chǎn)下的卵中。通過這種方式,，寄居蜂寄居并殺死蝴蝶的后代,。
對甘藍夜蛾赤眼寄居蜂來說，這是一種本能的,、固有的行為,。但對于與其有近親關(guān)系的廣赤眼蜂來說，就不那么適用了,。這種蜂寄居于多種蛾子和的蝴蝶,，其中包括大菜粉蝶。沒有經(jīng)驗的廣赤眼蜂像甘藍夜蛾赤眼寄居蜂一樣爬到菜粉蝶身上,，但沒有對交配過的雌蝶表現(xiàn)出偏好,。研究員因此得出結(jié)論說廣赤眼蜂對氰化苯?jīng)]有本能反應(yīng)。
由荷蘭瓦赫寧根大學(xué)昆蟲學(xué)實驗室的Ties Huigens博士領(lǐng)導(dǎo)的研究小組對這種寄居蜂能否習(xí)得這種行為感到好奇,。而情況恰好如此：如果廣赤眼蜂先前與交配過的蝴蝶有過寄居經(jīng)歷,，它就能對這種性攻擊氣味做出反應(yīng)。一旦搭過這類蝴蝶的“順風車”并將卵寄生于蝴蝶卵中之后,，它們就會準確地爬到交配過的蝴蝶身上并寄居,。僅僅只是“搭便車”或僅寄居于蝴蝶的卵中對它們來說并不足以發(fā)展長期記憶力。研究員總結(jié)說這種寄生蜂能學(xué)著將雌性蝴蝶的性攻擊氣味和將卵寄生于蝴蝶卵中的好處聯(lián)系在一起。
寄居蜂甚至在一天后就會繼續(xù)展示這種才學(xué)到的行為,，這是長期記憶的一個跡象,。為了演示它，研究員提供抑制劑,。服用抑制劑（蛋白質(zhì)合成的抑制劑）的寄居蜂在其搭蝴蝶的“便車”并將其卵寄居于蝴蝶卵中僅一天后,，他們就不能對這種性攻擊氣味做出反應(yīng)。顯然它們不能合成產(chǎn)生長期記憶所需的這種蛋白質(zhì),。研究表明這些僅有如此小的“大腦”（估計容量比10納升（nanoliters）還?。┑睦ハx能形成長期記憶，盡管這種記憶形成需要大量的能量,?？茖W(xué)家認為，昆蟲在形成長期記憶后更難以抵制類如干燥等的應(yīng)激狀態(tài),。
擁有長期記憶對這些生命短暫的寄居蜂來說非常重要,，因為一生中只有幾次機會搭交配過的蝴蝶的“便車”。如果它們很快就忘記一段有用的經(jīng)歷,，就有可能錯過這些僅有的機會,。來自瓦赫寧根的昆蟲學(xué)家預(yù)計這種策略是一種普遍的現(xiàn)象。因為對于多種謀殺其他昆蟲卵的寄居蜂來說,，這是很實用的,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS Published online before print January 12, 2009, doi: 10.1073/pnas.0812277106
Hitch-hiking parasitic wasp learns to exploit butterfly antiaphrodisiac
Martinus E. Huigensa,1, Foteini G. Pashalidoua, Ming-Hui Qianb, Tibor Bukovinszkya, Hans M. Smida, Joop J. A. van Loona, Marcel Dickea and Nina E. Fatourosa
aLaboratory of Entomology, Department of Plant Sciences, Wageningen University, P.O. Box 8031, 6700 EH Wageningen, The Netherlands; and
bDepartment of Forest Protection, Guangdong Academy of Forestry, No. 233 Guangshan 1 Road, Longdong, Tianhe, Guangzhou, Guangdong, 510520, People's Republic of China
Communicated by Thomas Eisner, Cornell University, Ithaca, NY, December 4, 2008 (received for review November 10, 2008)
Abstract
Many insects possess a sexual communication system that is vulnerable to chemical espionage by parasitic wasps. We recently discovered that a hitch-hiking (H) egg parasitoid exploits the antiaphrodisiac pheromone benzyl cyanide (BC) of the Large Cabbage White butterfly Pieris brassicae. This pheromone is passed from male butterflies to females during mating to render them less attractive to conspecific males. When the tiny parasitic wasp Trichogramma brassicae detects the antiaphrodisiac, it rides on a mated female butterfly to a host plant and then parasitizes her freshly laid eggs. The present study demonstrates that a closely related generalist wasp, Trichogramma evanescens, exploits BC in a similar way, but only after learning. Interestingly, the wasp learns to associate an H response to the odors of a mated female P. brassicae butterfly with reinforcement by parasitizing freshly laid butterfly eggs. Behavioral assays, before which we specifically inhibited long-term memory (LTM) formation with a translation inhibitor, reveal that the wasp has formed protein synthesis-dependent LTM at 24 h after learning. To our knowledge, the combination of associatively learning to exploit the sexual communication system of a host and the formation of protein synthesis-dependent LTM after a single learning event has not been documented before. We expect it to be widespread in nature, because it is highly adaptive in many species of egg parasitoids. Our finding of the exploitation of an antiaphrodisiac by multiple species of parasitic wasps suggests its use by Pieris butterflies to be under strong selective pressure.
