[Review] 警戒色與擬態的多樣性之演化：關於多態型、移動平衡與種化
原文標題：Evolution of diversity in warning color and mimicry: polymorphism, shifting balance, and speciation
摘要 [原文網址]
Mimicry and warning color are highly paradoxical adaptations. Color patterns in both Müllerian and Batesian mimicry are often determined by relatively few pattern-regulating loci with major effects. Many of these loci are “supergenes,” consisting of multiple, tightly linked epistatic elements. On the one hand, strong purifying selection on these genes must explain accurate resemblance (a reduction of morphological diversity between species), as well as monomorphic color patterns within species. On the other hand, mimicry has diversified at every taxonomic level; warning color has evolved from cryptic patterns, and there are mimetic polymorphisms within species, multiple color patterns in different geographic races of the same species, mimetic differences between sister species, and multiple mimicry rings within local communities. These contrasting patterns can be explained, in part, by the shape of a “number-dependent” selection function first modeled by Fritz Müller in 1879: Purifying selection against any warning-colored morph is very strong when that morph is rare, but becomes weak in a broad basin of intermediate frequencies, allowing opportunities for polymorphisms and genetic drift. This Müllerian explanation, however, makes unstated assumptions about predator learning and forgetting which have recently been challenged. Today's “receiver psychology” models predict that classical Müllerian mimicry could be much rarer than believed previously, and that “quasi-Batesian mimicry,” a new type of mimicry intermediate between Müllerian and Batesian, could be common. However, the new receiver psychology theory is untested, and indeed it seems to us unlikely; alternative assumptions could easily lead to a more traditional Müllerian/Batesian mimicry divide.
這篇文章的出現，綜合了近100年內發展的擬態理論，解釋擬態與警戒色的形成與演化。
擬態群對於演化學家而言，是件令人驚奇，卻又難以解釋的現象，雖然早在十八世紀就已提出這個現象的解釋，但至今仍然無法以一個全面的結果，說明這個現象如何形成，因此在不同領域的生物學家各持己見，因為沒人真的看到這個現象如何形成，有人用數學模型模擬幾萬個世代，推測斑紋的變化；有人從實驗行為學的角度，測試天擇對於擬態性狀的生成；有人從遺傳學的角度，測得擬態物種間的差異與性狀的變化，但無論哪個領域，都無法完美的解釋擬態的產生，當A理論在A領域生成時，在B領域就無法成立。這篇文章就概括所有領域的理論，提出對於現在擬態生物學的看法。
其中比較不一樣的地方在於，作者表達對於quasi-Batesian mimicry與Mullerian mimicry的看法，他們認為如果不在frequency-dependent 的前提下，只藉著receiver psychology是難以解釋擬態物種多態型的形成，也可能會失去擬態的多樣性，也就是不會有像目前看到這麼多樣化的擬態群，而是會趨於簡單化，就算可食度不同，仍然要回到捕食者是否能遇到這個不好吃的東西，仍然回到frequency-dependent的假設下，大大的質疑quasi-Batesian mimicry的可信度。
雖然如此，quasi-Batesian mimicry仍然無法被推翻，因為我們對於捕食者的反應仍了解的太少，有時甚至無法確定何為捕食者，因此理論跟行為學家對於這樣的推論仍然繼續提出證據，爭論依舊沒有結束。
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