A Lack of Robins

This classic book  by David Lack was unearthed from a box stored down in Devon for the last 20 years or so. Despite having been first published in 1943 it is light-hearted and very readable, instilling a sense of wonder with the science.as well as  encompassing serious and original thinking. 
Lack was teaching at Dartington Hall school at the time and over 4 years devised a system of coloured leg rings to identify individual birds and thus monitor their similar and different behaviours. Studying their song, he was one of the first to prove that it was an aggressive part of holding territory, rather than courtship .blandishment. 
Female robins are very emancipated for a small bird, in that they hold their own territory for part of the year, using song, and when paired will defend the shared territory along with the male, As both sexes have identical plumage humans find them difficult to distinguish, one from the other. I had rather thought that they would know the difference but it seems there can be problems of gender recognition, by males especially, at initial meetings. Potential lady partners are more likely to be driven off with a ghetto blast of song and a severe peck than wooed with a worm.