Host species of brood-parasitic birds can evolve features such as spots, squiggles and colours on their eggs that act like ‘signatures’ that are difficult for parasites to forge, helping hosts to detect and reject imposter eggs. In this new paper, we show that hosts of cuckoo finches and diederik cuckoos in Zambia have optimised this defence by arranging signature traits in unpredictable combinations. Thus, egg signatures are individually distinctive and hard for parasites to mimic, helping hosts distinguish parasitic eggs from their own. The paper arose from MPhil research by Eleanor Caves (co-authored by Martin Stevens, Edwin Iversen and Claire Spottiswoode) and the data were all obtained from Major John Colebrook-Robjent‘s wonderful egg collection. It is available open access in Proceedings of the Royal Society of London B.
Fieldwork in Zambia investigating the evolution of polymorphisms across species radiations
Dr Gabriel Jamie has just returned from a successful couple of months of fieldwork in Zambia as part of his Leverhulme Early Career Research Fellowship. For this research, Dr Jamie is exploring the evolution of polymorphisms across diverse avian family Cisticolidae which exhibit some of the most complex and diverse eggs of any group of birds in the world.