Philippine bird taxonomy and conservation, a response to Collar

Collar (2007) attacked a recent paper of mine (Peterson 2006) on a number of grounds; he raised some valid points, and detected some errors in detail. Here, I respond to his criticisms, clarify misunderstandings, and urge the field to move beyond the status quo to consider the need for new taxonomic viewpoints to benefit bird conservation globally.

Philippine bird taxonomy and conservation: a commentary on Peterson (2006)

A review by Peterson (2006) claims that a new species-level taxonomy leads to improved conservation insights for Philippine birds. However, it does not report how borderline taxonomic cases were dealt with, how many taxa and specimens were examined, how closely the evaluations were made, why four key museums were omitted from the survey, and why certain taxa were omitted despite their presence in museums visited. It provides no conclusive or accurate diagnoses in more than 40% of taxa on the first two pages of the Appendix, and overlooks another 16% that have already achieved species-level recognition. It unjustifiably asserts that work was hampered by lack of material, and inappropriately calls for the collection of a highly threatened taxon. It employs one unstable diagnostic method but preaches the virtue of another, entirely different but equally unstable. All these shortcomings undermine confidence in the paper's rigour; and reference to the recent conservation literature shows that in any case no new conservation insights have resulted.

Taxonomy is important in conservation: a preliminary reassessment of Philippine species-level bird taxonomy

Alpha taxonomy involves delineation of the basic unit of biology: the species. The concepts by which we define species, however, have been controversial, with several alternatives competing at present, some creating fewer and some more species units, depending on interpretation of species limits. Although it is tempting to assume that species concepts would have little interaction with the geographic foci of species richness and endemism — and some have so argued — this assumption does not withstand careful analysis. In this paper, I develop a first-pass assessment of Philippine bird taxonomy under an alternative species concept, and compare the results with the traditional biological species concept lists. Differences between the two lists were dramatic, but not just in numbers of species; rather, new, previously unrecognized or previously underappreciated foci of endemism were noted. A thorough understanding of the taxonomic basis of species lists is therefore critical to conservation planning.

Relations between body size, abundance and taxonomy of birds wintering in Britain and Ireland

We examine the relation between body size, abundance, and taxonomy in the wintering bird assemblages in Britain and Ireland. The regression slope of abundance on body size across species in both assemblages is not significantly different from that predicted by an ‘energetic equivalence rule’, but the proportion of the variance in abundance explained by body size is very low. Previous work on breeding bird assemblages has found the novel relation that the correlation between size and abundance across species within a tribe is itself positively correlated with the degree of taxonomic isolation of the tribe from other tribes in the bird fauna. We show that the same relation holds within bird tribes in the two wintering assemblages. Furthermore, evidence for this relation is found by using two different measures of bird abundance, despite these two abundance measures showing very different correlations with body size across species. Although these patterns in the data are consistent, some are not formally statistically significant ( p = 0.089 or greater). Excluding coastal, stocked, feral and recently colonizing species increased the significance of time since origin of a tribe on species abundances. We conclude that the relation between size and abundance in bird tribes is somehow related to bird taxonomy. While acknowledging the unlikely nature of such an effect, we tentatively propose hypotheses for two mechanisms that could produce the observed patterns.