Rothschild, M. & Clay, T., 1957
Fleas, Flukes and Cuckoos: A Study of Bird Parasites
A classic work. Quite a hard read, but a real eye-opener to anybody who thinks of birds as cute cuddly things. The sheer biodiversity supported by these "aviating zoological gardens" provides the only scientific justification for the large slice of the conservation funding cake that is directed at this small group of organisms.