How can birds still fly if they have to constantly eat to have enough energy to fly? Doesn’t eating make them so heavy that they need even more energy to keep flying?

Question

When I watch the birds at the feeding station in my garden, I notice that individual birds often eat a lot at once. Doesn’t all that food make them so heavy that they need more energy/food to fly than they can carry in flight?

In: Biology

Answer 1

How can an airplane fly if it has to constantly refuel? Because the engines are powerful enough that they can handle the extra weight from the fuel and whatever passengers or cargo might be aboard. Likewise, a bird’s flight muscles are strong enough to handle a little bit of extra food in its belly. Evolution might be blind but it ain’t stupid.