article_snippet: Bright lights in Europe’s cities may be causing urban blackbirds to reach sexual maturity quicker their country cousins.
article_snippet: Animal biologists from Glasgow University and the Max Planck Institute for Orntihology in Seewiesen, near Munich, fitted tiny light loggers to the backs of 100 blackbirds in the city of Munich and in a nearby forest.
article_snippet: tiny light loggers tracked the amount of light birds in both environments were exposed to each day and sent the data to experts.
article_snippet: tiny light loggers found that the additional light from artificial sources caused the city birds to perceive the days to be longer by 49 minutes on average.
article_snippet: the additional light from artificial sources had an effect on the city birds’ photoperiod, which is the part of the day that organisms use to time tiny light loggers daily and seasonal biology.
article_snippet: As a result, the birds in early March experienced the day length that the birds in early March country counterparts experienced in late March, according to the study published in journal Philosophical Transactions of the Royal Society B.
article_snippet: The city birds’ perception that the birds in early March were living at a later point in the year caused the birds in early March to reach sexual maturity in anticipation of breeding season 19 days earlier than the forest birds.
article_snippet: Professor Alberti’s study also discusses how songbirds are becoming tamer and bolder, as well as changing songbirds tunes to ensure songbirds acoustic signals are not lost in the noisy urban background.
highlights_snippet: Other studies have shown that bats are less active around artificial lighting and that blackbirds reach sexual maturity faster .