Congratulations to Mairenn Attwood for successfully submitting her MPhil thesis at the University of Cambridge, entitled ‘Angry birds: does it pay a cuckoo to parasitise a highly aggressive host?’. In it, Mairenn asks whether high levels of aggression by fork-tailed drongos affect hawk mimicry by the African cuckoo, and whether it pays cuckoos to specialise on such aggressive hosts. An amazing feat of field experimental work in Zambia (in collaboration with Jess Lund), analysis and writing in just one year of research – well done Mairenn!