Brood-parasitic birds lay eggs that mimic those of other species, to trick hosts into incubating their egg and raising their chick. Hosts often fight back by evolving egg colours and patterns that look different from those of their parasites, making an impostor easier to spot. In this study, we tested whether natural selection also drives hosts to evolve eggs that look different from those of other hosts, to avoid being susceptible to their neighbour’s specialist parasites when several host species live side by side. Using data from Major John Colebrook-Robjent‘s wonderful egg collection, we find evidence for this in the hosts of African brood-parasitic birds, which have evolved astonishingly diverse eggs. Read more in the full paper is published in Proceedings of the Royal Society of London B, by Eleanor Caves (former MPhil student), Martin Stevens and Claire Spottiswoode; see also a news article about this research in The Economist.
Dr Gabriel Jamie gave a talk on mimicry in the parasitic finches of Africa at Birdlife South Africa’s Virtual African Birdfair. Please also see Dr Jessica van der Wal’s talk on our sister research project on honeyguide-human mutualism (more information at www.AfricanHoneyguides.com) and many other great research talks by our colleagues at the FitzPatrick Institute of African Ornithology. Also visit the amazing line-up of other talks at the Virtual African BirdFair, including a talk on bird art by the brilliant Faansie Peacock who has generously allowed us to use his illustrations in several of our scientific publications. Thank you BirdLife South Africa!