PHYLOGENY AND RELATIONS AMONG ABUNDANCE, GEOGRAPHICAL RANGE AND BODY-SIZE OF BRITISH BREEDING BIRDS

Links between bird phylogeny and abundance, geographical range and body size relations were examined with use of a newly published data set on the numbers and distribution of British breeding birds. There was a negative correlation between abundance (and geographical range) and body size across species, but no significant correlations within non-passerine and passerine taxa considered separately. Abundance correlated positively with geographical range across species and within non-passerines and passerines. Three measures of phylogenetic relatedness of bird tribes were considered, termed 'rootedness', 'date of origin' and 'radiation date'. The date at which a tribe originated (measured as rootedness or date of origin) had a consistent but weak influence on the form of the relation between abundance and body size. Phylogeny was not implicated in the relation between geographical range and body size. Phylogenetically isolated tribes were more likely to show a positive correlation between abundance and body size than more recently evolved tribes. Results are discussed in the context of previous studies of both regional and local bird assemblages and the hypotheses suggested to explain associations with phylogeny.