[Article] 捕食者對於非完美擬態的一般化認知行為：以鳥類捕食者的觀點為例
(photo from http://digitaljournal.com/img/4/7/5/9/1/7/i/3/9/9/o/Parus_major_male.jpg)
原文標題：Generalization of mimics imperfect in colour patterns: the point of view of wild avian predators
[摘要][原文網址]
Current research of imperfect mimicry brings ambiguous results. Experiments simulating more natural conditions rather than laboratory experiments show lower willingness of avian predators to attack less perfect mimics. We decided to simulate a natural situation by testing responses of wild-caught adult avian predators (Great tit – Parus major) to variously perfect mimics of the red firebug (Pyrrhocoris apterus), which were in previous studies shown to elicit avoidance in Great tits. Presented mimics were perfect in all traits (firebug with its own colour pattern), imperfect in colour pattern (firebug with modified colour pattern), perfect in colour pattern, but imperfect in other visual traits (cockroach with firebug colour pattern), and imperfect in colour pattern as well as in other visual traits (cockroach with modified colour patterns). Modification of the pattern focused on the rounded spots on firebug's hemielytra, which is a conspicuous trait within the pattern. The pattern modification had no influence on the number of birds attacking the prey; nevertheless, birds spent more time observing the cockroaches that displayed the perfect firebug colour pattern than in the case of any other prey. Moreover, firebugs that displayed the perfect firebug colour pattern were observed for the shortest time (equal to that of the model – unmodified firebug). Cockroaches were attacked more often than firebugs, which suggest that birds were able to use additional visual cues (shape of legs and antennae) in prey recognition. Given these result, we conclude that differences in morphological traits characteristic for used prey taxa (true bugs, cockroaches) seem to be more important in the prey's protection than its colour pattern.
簡單的說，這篇就是把一個叫做firebug(Pyrrhocoris apterus，大陸翻做始紅椿)的蟲當做model，同時用Guyana spotted cockroach(就是杜比亞蟑螂)與始紅椿拿來做mimic，調整斑紋然後觀察大山雀(Parus major)反應的故事。
那個椿象長這樣
(photo from http://goo.gl/frKC7)
那個蟑螂長這樣(抖)
(photo from http://goo.gl/EfPnq)
然後他們做了以下處理
(1)完美的擬態：椿象+本身的斑紋
(2)不完美的擬態：椿象+調整過的斑紋
(3)完美的擬態：蟑螂+椿象原本的斑紋
(4)不完美的擬態：蟑螂
數據上採用的是處理的次數、被吃的次數與捕食者觀測的時間
以上實驗歸納出兩個結果：
(1)蟑螂被吃的比較椿象多
(2)越接近原本椿象的斑紋被吃的越少
結論是：鳥可以分辨哪個是最像的，而且可以藉由其他的視覺訊號，本作中指的是觸角與腳的形態，來分別哪些是可以吃的，哪些是不能吃的。
雖然這結論真是翻桌的簡單，不過這文章給我們一些提示：
(1)椿象真的很臭，臭到有一點不像都不行
(2)雖然蟑螂長得真的很不像，但是如果斑紋像的話，鳥的遲疑時間會變長，也就是逃跑的機會增加
(3)這題目說的"應該"是鳥類捕食者對於不完美擬態的一般化，理論上結果應該是不完美擬態的mimic應該可得到更多的保護，可是這實驗的結果是蟑螂無論擬態成功或不成功，被攻擊率都很高；而椿象的話被攻擊率都偏低，也就是說只有椿象的斑紋是有用的，鳥一開始應該就知道哪個是能吃不能吃，只是好像有點困惑「這東西怎麼會長成這樣？？」，感覺有點像黑色的蘋果，你雖然知道那是蘋果，但要你吃下去還是會遲疑這樣。就本篇來說，結論似乎比較偏向鳥如何分辨不同的物種來確認是否可食，與完美不完美擬態的討論連結似乎沒那麼強烈。
 原文標題：Generalization of mimics imperfect in col...){kind=link}
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