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

Links between bird phylogeny and abundance, geographical range and bod y 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 b ody size across species, but no significant correlations within non-pa sserine and passerine taxa considered separately. Abundance correlated positively with geographical range across species and within non-pass erines and passerines. Three measures of phylogenetic relatedness of b ird tribes were considered, termed 'rootedness', 'date of origin' and 'radiation date'. The date at which a tribe originated (measured as ro otedness or date of origin) had a consistent but weak influence on the form of the relation between abundance and body size. Phylogeny was n ot 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 evolve d 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.