Multiple hypotheses have been proposed to explain the variation of dorsal patterns observed in snakes, but no studies yet have tested them over broad taxonomic and geographical scales. The Viperidae offer a powerful model group to test eco-evolutionary processes that lead to disruptive and cryptic ornaments. We developed a database reporting dorsal ornamentation, ecological habitus, habitat features and climatic parameters for 257 out of 341 recognized species. Three patterns of dorsal ornamentation were considered: “zig-zag”, “blotchy” and “uniform” patterns. Phylogenetic comparative analyses were based on 11 mitochondrial and nuclear genes. Forty-eight species presented a zig-zag pattern type, 224 a blotchy pattern type and 32 a uniform pattern type. All the patterns showed a strong phylogenetic signal. Character phylogenetic reconstruction analyses suggested an ancestral state for blotchy ornamentation, with multiple independent evolutions of the other patterns. The blotchy pattern was more frequent in terrestrial species living in warm climates and sandy habitats, supporting the hypothesis of a disruptive function. The zig-zag pattern evolved independently in several isolated taxa, particularly in species living in cold climates and in dense vegetation or water-related habitats, supporting the hypothesis of disruptive and aposematic functions. Uniform coloration was particularly frequent in arboreal species, supporting the hypothesis of a cryptic function.

中文翻译：

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vi蛇装饰演变的生态地理决定因素

已经提出了多种假设来解释在蛇中观察到的背侧模式的变化，但是尚无研究在广泛的分类学和地理范围内对其进行检验。蛇蝎科提供了一个强大的模型组来测试生态进化过程，这些过程会导致破坏性和隐秘的装饰品。我们开发了一个数据库，报告了341个公认物种中的257个的背侧装饰，生态习性，生境特征和气候参数。考虑了三种背面装饰图案：“锯齿形”，“斑点状”和“均匀”形。系统发育比较分析基于11个线粒体和核基因。48种呈锯齿形，224种呈斑点状，32种呈均匀状。所有模式均显示出强烈的系统发育信号。字符系统发育重建分析表明斑点装饰的祖先状态，其他模式的多个独立演变。在居住在温暖气候和沙质生境中的陆地物种中，斑点现象更为常见，这支持了破坏功能的假设。之字形模式在几个孤立的分类单元中独立发展，特别是在寒冷的气候中以及在茂密的植被或与水有关的栖息地中的物种，支持了破坏性和特异功能的假说。均匀着色在树栖物种中特别常见，支持了隐性功能的假设。在居住在温暖气候和沙质生境中的陆地物种中，斑点现象更为常见，这支持了破坏功能的假设。锯齿形在几个孤立的类群中独立发展，特别是在寒冷的气候中以及在茂密的植被或与水有关的栖息地中的物种，支持破坏性和特异功能的假说。均匀着色在树栖物种中特别常见，这支持了隐函数的假设。在居住在温暖气候和沙质生境中的陆地物种中，斑点现象更为常见，这支持了破坏功能的假设。锯齿形在几个孤立的类群中独立发展，特别是在寒冷的气候中以及在茂密的植被或与水有关的栖息地中的物种，支持破坏性和特异功能的假说。均匀着色在树栖物种中尤为常见，这支持了隐函数的假设。