Migrating birds are arriving at their breeding grounds earlier as global temperatures rise, according to a study which looked at hundreds of species across five continents. For every degree the temperature rises, the birds arrive one day earlier, researchers at the University of Edinburgh found.

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Migrating birds are arriving at their breeding grounds earlier as global temperatures rise, according to a study which looked at hundreds of species across five continents. For every degree the temperature rises, the birds arrive one day earlier, researchers at the University of Edinburgh found.