From the nut-cracking crows of Sendai to ‘Turdus urbanicus’ (the new urban blackbird), animals are changing their behaviour and evolution in cities – and in dramatic and surprising ways

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In tune with their human population, cities have been assembled from immigrants from around the globe. Either intentionally or accidentally, people have been ferrying flora and fauna across the world for as long as they have been trading and travelling. 

The ubiquitous Javan myna birds of Singapore first arrived as pets from Indonesia around 1925, sought after at the time as virtuoso impersonators. They now rival the human population in terms of numbers (and noise). The bright-green ring-necked parakeet, originally hailing from India and Africa, has established itself in European cities thanks to the caged-bird trade for much of the 20th century. In London, they feast on seeds of horse chestnut trees brought from Greece.

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