“穆氏擬態(tài)物種”是有毒的或不好吃的潛在獵物物種,，它們與其所模仿的物種并不是密切相關(guān),，但卻形成了相似的警告色,，以遏阻它們共同的捕食者,，這種本領(lǐng)是在該過(guò)程中通過(guò)數(shù)量上的優(yōu)勢(shì)形成的,。在“競(jìng)爭(zhēng)性排他”有利于一個(gè)擬態(tài)物種而以其他擬態(tài)物種為代價(jià)的情況下,，不清楚這個(gè)效應(yīng)是否足以維持它們的共存,。Martin Taylor及其同事在關(guān)于一組物種豐富的熱帶鯰魚(yú)類群中的“穆氏擬態(tài)”的一項(xiàng)研究中研究了這個(gè)問(wèn)題。利用形態(tài)測(cè)定和穩(wěn)定同位素分析,，他們發(fā)現(xiàn),，擬態(tài)物種并不占據(jù)相同的生境，所以它們并不直接競(jìng)爭(zhēng)食物,，這樣便能解釋它們的共存能力,。（生物谷Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature09660
Competition and phylogeny determine community structure in Müllerian co-mimics
Markos A. Alexandrou,Claudio Oliveira,Marjorie Maillard,Rona A. R. McGill,Jason Newton,Simon Creer& Martin I. Taylor
Until recently, the study of negative and antagonistic interactions (for example, competition and predation) has dominated our understanding of community structure, maintenance and assembly1. Nevertheless, a recent theoretical model suggests that positive interactions (for example, mutualisms) may counterbalance competition, facilitating long-term coexistence even among ecologically undifferentiated species2. Müllerian mimics are mutualists that share the costs of predator education3 and are therefore ideally suited for the investigation of positive and negative interactions in community dynamics. The sole empirical test of this model in a Müllerian mimetic community supports the prediction that positive interactions outweigh the negative effects of spatial overlap4 (without quantifying resource acquisition). Understanding the role of trophic niche partitioning in facilitating the evolution and stability of Müllerian mimetic communities is now of critical importance, but has yet to be formally investigated. Here we show that resource partitioning and phylogeny determine community structure and outweigh the positive effects of Müllerian mimicry in a species-rich group of neotropical catfishes. From multiple, independent reproductively isolated allopatric communities displaying convergently evolved colour patterns, 92% consist of species that do not compete for resources. Significant differences in phylogenetically conserved traits (snout morphology and body size) were consistently linked to trait-specific resource acquisition. Thus, we report the first evidence, to our knowledge, that competition for trophic resources and phylogeny are pivotal factors in the stable evolution of Müllerian mimicry rings. More generally, our work demonstrates that competition for resources is likely to have a dominant role in the structuring of communities that are simultaneously subject to the effects of both positive and negative interactions.
