Scientists Crack Egg Forging Evolutionary Puzzle
Published:21 Apr.2022 Source:University of Cambridge
Around the world, many birds side-step the costs of parenthood by laying their eggs in the nest of other species. This lifestyle, termed "brood parasitism," has many advantages but also presents challenges such as how to convince the other species to accept a foreign egg. Many brood parasites achieve this by mimicking the colours and patterns of their host's eggs, but some exploit the care of several different host species whose eggs all look different.
How then can a single brood-parasitic bird species simultaneously mimic the eggs of several different bird species to trick them into raising their young? And how do these parasitic forgers pass this ability on to their young despite interbreeding between birds raised by different hosts? These questions have been puzzling scientists for more than a century. Now genetic research by an international team led by Professor Claire Spottiswoode from the University of Cambridge's Department of Zoology and the FitzPatrick Institute of African Ornithology, University of Cape Town; and Professor Michael Sorenson at Boston University, has made a major breakthrough, and their findings may be bad news for the egg forgers.