This is Bird Note.

We've all heard about the early bird getting the worm.

We know it is sound advice about initiative and timely action,

and we can almost see that robin leaning back and tugging that recalcitrant worm out of the ground.

Research shows, however, that birds dining early and heavily may lower their life expectancy.

A study of three North American woodland bird species found that socially dominant birds

stay lean during the day and then

stoke up when it's most important, later in the day, before a cold night. At night, birds avoid

hypothermia by metabolizing fat, and by staying lean through most of the day, dominant birds are

more agile in avoiding predators. Subordinate birds

have to look for food whenever and wherever they can find it, and carry fat on their bodies

to hedge against unpredictable rations. Dominant birds, which can push subordinates off food,

can choose when they eat, and so lessen their odds of being eaten themselves.

Therefore, at least in the woodland birds' world, the revised moral might read,

Get the worm late in the day. You'll sleep better and live longer.

For Bird Note, I'm Michael Stein.

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