Zoological Research Museum Alexander Koenig, Bonn, Germany.
PLoS One. 2011 Mar 31;6(3):e18101. doi: 10.1371/journal.pone.0018101.
The use of DNA based methods for assessing biodiversity has become increasingly common during the last years. Especially in speciose biomes as tropical rain forests and/or in hyperdiverse or understudied taxa they may efficiently complement morphological approaches. The most successful molecular approach in this field is DNA barcoding based on cytochrome c oxidase I (COI) marker, but other markers are used as well. Whereas most studies aim at identifying or describing species, there are only few attempts to use DNA markers for inventorying all animal species found in environmental samples to describe variations of biodiversity patterns.
METHODOLOGY/PRINCIPAL FINDINGS: In this study, an analysis of the nuclear D3 region of the 28S rRNA gene to delimit species-like units is compared to results based on distinction of morphospecies. Data derived from both approaches are used to assess diversity and composition of staphylinid beetle communities of a Guineo-Congolian rain forest in Kenya. Beetles were collected with a standardized sampling design across six transects in primary and secondary forests using pitfall traps. Sequences could be obtained of 99% of all individuals. In total, 76 molecular operational taxonomic units (MOTUs) were found in contrast to 70 discernible morphospecies. Despite this difference both approaches revealed highly similar biodiversity patterns, with species richness being equal in primary and secondary forests, but with divergent species communities in different habitats. The D3-MOTU approach proved to be an efficient tool for biodiversity analyses.
CONCLUSIONS/SIGNIFICANCE: Our data illustrate that the use of MOTUs as a proxy for species can provide an alternative to morphospecies identification for the analysis of changes in community structure of hyperdiverse insect taxa. The efficient amplification of the D3-marker and the ability of the D3-MOTUs to reveal similar biodiversity patterns as analyses of morphospecies recommend its use in future molecular studies on biodiversity.
近年来，基于 DNA 的方法在评估生物多样性方面的应用越来越普遍。特别是在热带雨林等生物多样性丰富的生境或高度多样化或研究不足的分类群中，它们可以有效地补充形态学方法。在该领域最成功的分子方法是基于细胞色素 c 氧化酶 I（COI）标记的 DNA 条形码，但也使用其他标记。虽然大多数研究旨在识别或描述物种，但很少有尝试使用 DNA 标记对环境样本中发现的所有动物物种进行编目，以描述生物多样性模式的变化。
方法/主要发现：在这项研究中，对 28S rRNA 基因的核 D3 区进行分析，以界定类似物种的单位，与基于形态种区分的结果进行比较。从这两种方法中得出的数据用于评估肯尼亚几内亚-刚果雨林中隐翅虫科甲虫群落的多样性和组成。使用陷阱在六个主要和次要森林的横截线上使用标准化采样设计收集甲虫。可以获得所有个体的 99%的序列。总共发现了 76 个分子分类操作单元（MOTU），而可辨别的形态种有 70 个。尽管存在这种差异，但这两种方法都揭示了高度相似的生物多样性模式，主要森林和次要森林中的物种丰富度相等，但不同生境中的物种群落存在差异。D3-MOTU 方法被证明是生物多样性分析的有效工具。
结论/意义：我们的数据表明，使用 MOTU 作为物种的代表可以替代形态种鉴定，用于分析高度多样化昆虫类群的群落结构变化。D3 标记的有效扩增以及 D3-MOTU 能够揭示与形态种分析相似的生物多样性模式，建议在未来的生物多样性分子研究中使用。
