00313nas a2200085   4500008004100000245006300041210006200104100002100166856004000187       2012                        eng d00aAugustin Pyramus de Candolle: Theorist of Natural Taxonomy0 aAugustin Pyramus de Candolle Theorist of Natural Taxonomy1 aBorges, Leonardo  uhttps://ubsc.myspecies.info/node/1902060nas a2200133   4500008004100000245007200041210006900113300000800182490000700190520165000197100001901847700002001866856004001886       2012                        eng d00aSpecies Delimitation: Inferring Gaps in Morphology across Geography0 aSpecies Delimitation Inferring Gaps in Morphology across Geograp  a1940 v613 a<p>Species are commonly delimited on the basis of gaps in patterns of morphological variation, but there seems to be little recent work on methods to objectively assess such gaps. Here, we introduce a statistical approach that uses measurements of continuous morphological characters and geographic variation in those characters to (i) measure the strength of the evidence for the existence of a gap in morphological variation between two hypothesized species and (ii) examine if a gap in morphological variation between two hypothesized species can be explained by an alternative hypothesis of geographic variation within a species. This approach is based on recent developments in analyses of multivariate normal mixtures, estimates of multivariate tolerance regions, and principal coordinates of neighboring matrices. We demonstrate the application of the approach by examining previously proposed hypotheses of species limits in the plant genus Escallonia. We discuss the main features of the method, including potential limitations, in relation to other approaches that use gaps in morphological variation as a criterion for species delimitation. The method we propose can help strengthen the link between the theory and practice of species delimitation by increasing the transparency and consistency of taxonomic decisions based on morphology, thus contributing to integrative approaches for species delimitation that consider morphological and geographic data on an equal footing with other kinds of information. [Geographic variation; morphological variation; normal mixture; operational criteria; species limits; tolerance limit.]</p>
1 aZapata, Felipe1 aJiménez, Iván  uhttps://ubsc.myspecies.info/node/1200228nas a2200085   4500008004100000245002300041210002300064100001600087856003900103       2012                        eng d00aList of Literature0 aList of Literature1 aMayo, Simon  uhttps://ubsc.myspecies.info/node/4