schneideri to feed year-round in the aseasonal habitat in which i

schneideri to feed year-round in the aseasonal habitat in which it occurs. We predict that future studies of small-bodied species from climates that allow for extended periods of feeding will continue to show that frequent reproduction is more widespread among vipers

than is currently assumed. “
“Three sympatric species of sea kraits (Laticauda spp.) were found to have different degrees of aquatic tendencies at Orchid Island (=Lanyu), Taiwan. All species move to coastal areas at night. Generally, Laticauda semifasciata remain submerged RXDX-106 cost in sea water, L. laticaudata emerge onto land, but remain not far from the water’s edge, while L. colubrina tend to move farther inland away from the water. Attributes of morphology and physiology can influence the performance and survival of snakes differently in aquatic

or terrestrial habitats, so we hypothesize that some attributes of structure and function will vary among these three sympatric species of sea kraits. We measured parameters of the body shape, vascular lung, saccular lung and hematocrit of sea kraits to investigate possible morphological correlates of their physiology. The most aquatic species, L. semifasciata, had a significantly more laterally flattened body form, larger saccular lung volume and higher hematocrit than the other two species, whereas only few differences were found between the two less aquatic species. L. laticaudata had a significantly higher hematocrit than L. colubrina. “
“The study of asymmetry can provide insights into genetic and environmental influences mTOR inhibitor on organismal development. Directional asymmetry (DA)

can be either adaptive or non-adaptive, whereas fluctuating asymmetry (FA) – defined as small non-directional departures from symmetry in bilateral traits – is thought to be an indicator of genetic or environmental stress experienced during development. Using data from 28 European populations, we assessed the degree of DA and FA in the lateral plates of threespine sticklebacks Gasterosteus aculeatus and surveyed the direction of DA and differences in levels of DA and FA in different habitat types (viz. marine, lake and river populations). DA differed between habitats, with right-biased DA found 上海皓元 in the marine populations and no directional bias found in lake and river populations. Differences in DA among habitats may be a by-product of habitat-specific developmental instability resulting in asymmetry, or it may indicate habitat-specific differences in selection against/for symmetry, as has been proposed in previous research of sticklebacks. Also, the presence of FA varied depending upon habitat type, but it also depended on plate morph – a variable confounded with the habitat effect. While we cannot rule out factors such as stress as a cause of population differences in FA, it may also simply be a by-product of other evolutionary processes (e.g. lateral plate number reduction) without functional basis.

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