Contrasting Patterns of Population Genetic Structure in Two Great Basin Stoneflies

Shifts in species distributions caused by climatic oscillations may lead to geographic isolation of populations and fewer opportunities for genetic exchange among locations. Examining trends in genetic relationships among stonefly populations can help us predict how organisms might respond to environmental changes. Prior work established that isolated montane populations of the stonefly Doroneuria baumanni had high levels of genetic structure within the Great Basin and that this diversification occurred during the Pleistocene. This differentiation may have resulted from historical climatic oscillations. With this in mind, we evaluated the contemporary genetic structure of another Great Basin stonefly, Hesperoperla pacifica. Because H. pacifica has relatively broader habitat requirements, we predicted its populations would display less genetic structure than those of D. baumanni. We estimated genetic differentiation among and within 12 populations of H. pacifica using 568 base pairs of the mitochondrial gene cytochrome b gene. FST estimates indicate that H. pacifica populations are less structured than D. baumanni, which had showed deep levels of divergence across limited geographic distances. These results confirm the benefits of a comparative approach to understanding the phylogeography and population genetic structure of stoneflies of the Great Basin

The Serpent And The Egg: Unidirectional Evolution Of Reproductive Mode In Vipers?

This study investigated the reliability and concurrent validity of active shoulder elevation in the scapular plane (scaption) using a digital inclinometer and goniometer. Two investigators used a goniometer and digital inclinometer to measure scaption on 30 asymptomatic participants in a blinded repeated measures design. Good reliability was present with intraclass correlation coefficients (ICCs) for intrarater reliability of goniometry = 0.87, intrarater digital inclinometry = 0.88, interrater goniometry = 0.92, and interrater digital inclinometry = 0.89. The minimal detectable change (MDC 95) for the interrater analysis indicated that a change equal to or greater than 8 degrees for goniometry and 9 degrees for inclinometry is required to be 95% certain that the change is not due to intertrial variability or measurement error. The concurrent validity between goniometry and digital inclinometry was excellent with an ICC value of 0.94 for both raters. The 95% limits of agreement suggest that the difference between these two measurement instruments can be expected to vary by up to ±11 degrees. The results support the interchangeable use of goniometry and digital inclinometer for measuring scaption. Clinicians and researchers should consider the MDC values presented when interpreting change during subsequent measurement sessions. © 2012 Informa Healthcare USA, Inc

Morphological And Molecular Evidence For Phylogeny And Classification Of South American Pitvipers, Genera Bothrops, Bothriopsis, And Bothrocophias (Serpentes: Viperidae)

Species in the genus Bothrops s. l. are extraordinarily variable in ecology and geography, compared with other genera in the subfamily Crotalinae. In contrast to the trend of splitting large and variable groups into smaller, more ecologically and phenotypically cohesive genera, the genus Bothrops has remained speciose. In addition, previous phylogenetic analyses have found Bothrops to be paraphyletic with respect to the genus Bothriopsis. Taxonomic arguments exist for synonymizing Bothriopsis with Bothrops, and for splitting Bothrops into smaller genera, but the greatest hindrance to taxonomic revision has been incomplete phylogenetic information. We present a phylogeny of Bothrops, Bothriopsis, and Bothrocophias based on 85 characters of morphology and 2343 bp of four mitochondrial gene regions, and with significantly greater taxonomic coverage than previous studies. The combined data provide improved support over independent datasets, and support the existence of discrete species groups within Bothrops. The monophyly and distinctness of these groups warrant recognition at the generic level, and we propose a new taxonomic arrangement to reflect these findings. © 2009 The Linnean Society of London