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1 .This is Scientific American's 60-Second Science. I'm Karen Hopkin. This'll just take a minute.
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2 .We usually think of evolution as something that happens over eons, in remote places where people rarely venture.
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3 .Not something that happens around the backyard birdfeeder in just a few decades.
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4 .But a study in the journal Current Biology suggests that feeding birds in winter can influence their course of evolution.
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5 .The birds in this study were central European blackcaps, a common kind of warbler.
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6 .In spring, they breed in southern Germany.
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7 .And when winter comes, they all fly south to the Mediterranean.
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8 .At least they used to.
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9 .In the 1960s, folks in Britain started putting out seed in winter.
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10 .And the blackcaps split into two distinct groups.
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11 .One goes to Spain to nosh on fruits and olives, the other heads north to take advantage of the easy English pickin's.
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12 .The two populations may even be splitting into two species.
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13 .The blackcaps that winter in England tend to mate with each other when they return to Germany.
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14 .So they're starting to look different from the birds that go south.
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15 .Their beaks are longer and narrower, less suited to supping on Spanish olives.
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16 .As birds of a feather, they definitely flock together.
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17 .And to some degree, they have a bunch of bird-feeding Brits to thank.
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18 .Thanks for the minute, for Scientific American's 60-Second Science. I'm Karen Hopkin.
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