Summary: | A literature review shows that qualitative dichotomies describing interspecific differences in the movement patterns of foraging animals are widely-used and biologically important, but fraught with ambiguity. Consistent use of the terminology from foraging theory and stronger quantification are proposed to increase clarity and facilitate more rigorous tests of hypotheses. Greater consideration of intraspecific variation is also needed. In forest bird and lizard communities, move-frequency distributions are bimodal, supporting a dichotomous view, but there is important variation within the statistical modes. Fish species with more red muscle are more mobile than species with less red muscle, but the frequency distribution of the proportion of red muscle does not match subjective, dichotomous classifications. A quantitative field investigation of foraging young-of-the-year brook charr (Salvelinus fontinalis) reveals significant individual differences in movement patterns that are more strongly related to microhabitat use and diet, than to morphological and environmental parameters thought to influence swimming capability.
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