Abstract
<jats:title>Abstract</jats:title><jats:p>Data for five closely related species of gammarid crustaceans are used to examine interspecific relationships between the breadth of fundamental tolerance or capacity and geographical range size.<jats:italic>Gammarus duebeni</jats:italic>is, almost without exception, the most tolerant species and that with the best physiological performance. Although there is some limited variation, the remaining species can be ranked broadly in the sequence<jats:italic>G. zaddachi</jats:italic> ><jats:italic>G. salinus</jats:italic> > <jats:italic>G. oceanicus > G. locusta</jats:italic>. The wide tolerance and high performance of<jats:italic>G. duebeni</jats:italic>is associated with the occupation of a wider range of environmental ‘types’ than any other of the species. In terms of geographical range size, the species can be ranked from most to least widespread in the sequence<jats:italic>G. oceanicus</jats:italic> ><jats:italic>G. duebeni</jats:italic> > <jats:italic>G. zaddachi</jats:italic> > <jats:italic>G. salinus</jats:italic> > <jats:italic>G. locusta</jats:italic>. This provides little support for Brown’s hypothesis, or the argument that the more widely distributed species within a taxonomic assemblage also tend to have the widest fundamental niches. However, if marine (<jats:italic>G. oceanicus</jats:italic>and<jats:italic>G. locusta</jats:italic>) and estuarine (<jats:italic>G. duebeni</jats:italic>,<jats:italic>G. zaddachi</jats:italic>, G. salinus) species are considered separately, then in each case the species with the largest geographical range is also the most tolerant/best performer. In this sense, the jack‐of‐all‐trades is the master‐of‐all, rather than the master‐of‐none.</jats:p>
Original language | English |
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Pages (from-to) | 179-188 |
Number of pages | 0 |
Journal | Global Ecology and Biogeography |
Volume | 10 |
Issue number | 2 |
DOIs | |
Publication status | Published - Mar 2001 |