Equilibrium of species’ distributions with climate

摘要: The degree to which species’ distributions are at equilibrium with current climate is an important issue in the ecological literature (Davis 1986, Gaston 2003). Distinguishing relative roles of present and past climates determining not only theoretical interest, but key understanding responses species change. Recent work has demonstrated significant departures from for tree Europe (Svenning Skov 2004), yet differences can be expected across organisms whose dispersal abilities (and hence ability track changing conditions) vary greatly. Here we assess between present-day vascular plant, breeding bird, amphibian reptile assemblages Europe. Our analyses included all know European birds (Hagemeijer Blair 1997), amphibians reptiles (Gasc et al. ca 20% flora (Jalas Suominen 1972 /1996, Lahti Lampinen 1999). Assemblages plants were found relatively closer than amphibians. Results suggest that plant bird change more likely accurately forecasted by models correlating climate, will least capable shifting distributions, making them most vulnerable rapid environmental changes. Species said if they occur climatically suitable areas whilst being absent unsuitable ones (Hutchinson 1957). observation many trivial. critical question how distant distributions. Accurate estimates limits tolerance obtained means controlled experiments (Chuine Beaubien 2001). However, these expensive time consuming attempts measure large numbers have previously used ‘‘bioclimatic envelope’’ approach, whereby observed correlated variables approximate requirements (for review see Pearson Dawson With this ratio modelled interpreted as indicating 2004). By relying on (which inherently reflect multiple range determinants, both historical ecological) determine requirements, methodology underestimate true variation able tolerate. An alternative approach consists measuring patterns covariation (Ferrier 2002). It assumed then assemblage composition high. A weak biota may indicate tend occupy available spaces due and/or factors (notably competition limited ability). In some cases it could also imply selected parameters do adequately describe climatic determinants distribution assemblages. However possibility inherent any correlational (including bioclimate-envelope modelling) choice needs supported existing knowledge ecologies. FORUM a lighter channel communication readers contributors; aims stimulate discussion debate, particularly presenting new ideas suggesting interpretations formal research papers published ECOGRAPHY elsewhere. prose encouraged no summary required. Contributions should concise point, short bibliography. Formal papers, however short, considered.