The question of whether or not parasite phylogeny provides information
about host relationships ('comparative parasitology') reached a peak
in 1957 in a vigorous debate between Gunther Timmermann and Ernst Mayr
. Timmermann argued that parasites were associated with their hosts by
descent and that this produced congruent host and parasite phylogenie
s. In contrast, Mayr argued that parasites were often associated by co
lonization and that this led to incongruence between host and parasite
phylogenies. To test these differing views, Adrian Paterson, Russell
Gray and Graham Wallis derived a procellariiform phylogeny. This tree
is here compared with Timmermann's tree based on the relationships of
feather lice. Timmermann's tree is more similar to the seabird phyloge
ny that would be expected by chance. Thus, support is found for the 'c
omparative parasitology' approach.