Abstract

As it has presently become evident, reproductive isolation can no longer be considered as the leading criterion for estimating the species limits, but it is still used for determining the status of the majority of morphs. The presence/absence of hybridization between individuals is not directly related to the degree of their evolutionary insularity. Hybridization can result in the origin of new morphs including those that have species status. The application of phylogenetic methods is justified in reconstructing the relation links within complex groups including the morphs of various evolutionary levels (from geographical races to “good” species), the relationships between which are exacerbated by hybridogenous polymorphism and/or the hybridization origins of their populations. Taking into account both new data and new conceptions, we suggest genuine interrelated definitions of concepts such as species, subspecies, and semispecies in birds. The definitions are based on two main criteria: biological, i.e., an evaluation of the reproductive relations of the particular morphs with each other, and phylogenetic, i.e., an evaluation of their evolutionary age and kinship. The main feature of a species as an evolutionary entity should be considered through its stability in time even when its reproductive isolation is periodically broken. Geographic intraspecies races show sustainable variations of different degrees, but they have no reproductive isolation; they breed upon contact and form intergradation zones. They are taxonomically denoted as subspecies. Descriptions of new subspecies are viable to the limits that reflect the species’ natural geographic structure to the fullest extent. For the young morphs that have reached the level of species insularity in the course of evolution, it seems appropriate to restore a semispecies category. Semispecies show significant morphological differences and distinguished ecological particularities, as a rule, but they are connected to closely related morphs by gene flows in contact zones. Distinguishing this category is not regulated by the International Code of Zoological Nomenclature and, as splitter tendencies prevail in modern systematics, semispecies are more often equated to species; i.e., they have binominal names. We propose to denote the attribution of a semispecies to a particular species group (superspecies) in parentheses between genus and species names. Thus, it would become possible to outline natural complexes and avoid a groundless increase in the taxonomic statuses of morphs in the stage of development. Representatives of distant phylogenetic lines (morphs that separated historically long ago) are not to be considered as semispecies even in the cases of their reproductive isolation being broken and a steady hybridization existing between them.

中文翻译：

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鸟类的概念：理论与实践

摘要

从目前的情况来看，生殖隔离已不再被视为估计物种限度的主要标准，但仍用于确定大多数形态的状态。个体之间杂交的存在与否与他们进化孤立的程度没有直接关系。杂交可以导致新形态的起源，包括具有物种状态的形态。系统发育方法的应用在重建复杂群体内的联系方面是合理的，包括各种进化水平（从地理种族到“好”物种）的形态，它们之间的关系因杂种多态性和/或它们的杂交起源而加剧人口。考虑到新数据和新概念，我们建议对鸟类的物种，亚种和半物种等概念进行真正的相互关联的定义。这些定义基于两个主要标准：生物学的，即对特定形态彼此之间生殖关系的评估，以及系统发育的，即对其形态和亲缘关系的评估。作为物种的进化实体，其主要特征应通过其时间稳定性来加以考虑，即使其生殖隔离被定期打破。地理种内种族显示出不同程度的可持续变化，但它们没有生殖隔离。它们在接触时繁殖并形成过渡带。它们在分类上被称为亚种。对新亚种的描述在最大程度上能够反映该物种自然地理结构的范围内是可行的。对于在进化过程中已达到物种孤岛水平的幼小形态，恢复半物种类别似乎是适当的。通常，半物种显示出明显的形态差异和独特的生态特殊性，但它们通过接触区中的基因流与紧密相关的形态联系在一起。区分这一类别不受《国际动物命名法》的约束，并且由于现代系统系统中普遍存在分裂倾向，因此半物种通常被称为物种。即，它们具有二项式名称。我们建议在属和种名之间的括号内，将半种归因于特定的种群（超种）。因此，将有可能勾勒出天然的复合物，并避免在发育阶段形态学分类状态的毫无根据的增加。远距离的系系的代表（历史上很久以前分离的形态）即使在生殖分离被破坏并且它们之间存在稳定杂交的情况下也不应被视为半物种。