Crested pigeons make a rapid trilling sound when they take flight that can be used to warn others of danger. But what is it that makes the sound?
Ordinary grey bird feathers placed under X-ray fluorescence reveal beautiful patterns of elements like zinc, telling a story of feather growth and the environments the birds have experienced.
For the first time, feathers, bone and skin of the earliest birds have been found, trapped in amber.
Bird feathers can tell us a lot about their owners and the places they visit.