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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 .If you’ve ever been to an all-you-can-eat buffet, you know how important it is to carefully weigh your options.
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3 .You don’t want to fill up on salad when so many calorie-laden delights await.
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4 .It seems some birds also weigh their mealtime choices literally.
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5 .A study finds that Mexican Jays pick up and shake peanuts to assess their relative heft before choosing one.
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6 .That report is served up in the Journal of Ornithology.
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7 .Foods that hide their edible bits on the inside present a challenge to hungry diners.
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8 .How can you tell which fruits are ripe or which shells harbor the biggest nuts?
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9 .We humans knock on melons or squeeze avocados.
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10 .But how do other species select the highest quality snacks?
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11 .To find out how the jays do it, researchers fiddled with their feed.
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12 .First they doctored peanuts so that some contained three nuts while others had none.
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13 .When they offered these pods to some jays, the birds turned their beaks up at the empty shells and instead chose those that were full.
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14 .And when the jays were allowed to choose between normal peanuts and those that weighed just one gram more,
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15 .because the researchers had stuffed them with clay, the birds again went for the heavier meal.
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16 .Videos revealed that the jays shake the nuts before selecting one,
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17 .which apparently lets them gauge the nut’s mass and perhaps also listen for the rattle of a well-packed shell.
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18 .Pretty clever for a bird brain.
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19 .Thanks for the minute, for Scientific American's 60-Second Science. I'm Karen Hopkin.
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