五種燕雀類是否對於貝氏擬態物種具有辨識能力？
photo from robin (wiki)
photo from blackcap (wiki)
photo from black redstrat (wiki)
標題：Five species of passerine bird differ in their ability to detect Batesian mimics
摘要
Multiple predators affect the evolution of aposematic signals in nature and these predators may substantially differ in terms of ecological and cognitive parameters. However, most experimental studies testing the evolution of Batesian mimics use only a single species of predator (usually the great tit or a domestic chick). Therefore, in the present study, we experimentally tested the responses of five passerine predators to an artificially made Batesian mimic (a cockroach equipped with the warning pattern of the red firebug) with respect to their dietary ecology. Half of the individuals of each species were fed on unmodified roaches before the experiment, whereas the other half were fed with mealworms and thus had no previous experience with roaches. We found that Batesian mimics were better protected than inconspicuous prey against inexperienced great tits and robins alone. The other three bird species showed high level of neophobia; therefore, the effect of warning coloration could not be assessed. We also found that experienced birds attacked a greater number of Batesian mimics compared to inexperienced individuals of all tested species, with the exception of blackcaps. In the great tits, robins, and blue tits, a significant number of experienced birds attacked the Batesian mimic, which was possibly the result of a learned search image for a roach. Our results suggest that using a limited array of predators to describe evolutionary processes forming the diversity of antipredatory strategies of the prey may be biased and need not describe the situation occurring in nature.
大部分用行為學的方式討論擬態與警戒色的功能性與演化的時候，通常這些作者選的是特定的幾種鳥類，最常見的就是家雞或是大山雀，但是在自然環境中，能夠推動這些斑紋演化的捕食者可不只一種，只用少數幾種「模式物種」真的能正確的反應實際的演化歷程嗎？還是有偏差的結果呢？
這個研究就在探討五種燕雀類對於擬態斑紋的選擇行為，其實就是探索其他可能選汰演化的捕食者，或是其他可用來放在行為實驗中作為捕食者的可能性。作者選擇五種燕雀鳥類，分別是大山雀(great tit)、藍山雀(blue tit)、知更鳥 (robin)、赭紅尾鴝 (black redstart)與黑頭鶯 (blackcap)，讓牠們去選擇椿象(firebug)與蟑螂，看牠們對於貝氏擬態的mimic是否會避忌。
結果顯示大山雀與知更鳥分的出來擬態的椿象，而且會減少捕食牠們，其他三種則有恐新症(neophobia，傾向不去嘗試新的事物的行為)，因此無法得知接下來是否會有避忌行為。大山雀、知更鳥與藍山雀的有經驗的個體不只分的出來貝氏擬態的椿象，而且知道可以吃。
這個實驗就是一個前導性的研究，就是在測試到底還有什麼鳥是能用在測試這種行為實驗，也某種程度上告訴我們，不同種的行為差異很大，甚至同種的捕食者不同族群行為也有差異（見這篇），所以一直用同種，或是同族群的捕食者究竟能解釋多少型塑擬態的機制，或是應該採用很多種不同的捕食者來探討背後的理論，都是未來可以繼續討論的方向。
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