Swim or fly, that is the question. Penguins are clumsy in the air, howeverin the water they unfoldperfectly, and this could be one of the reasons why these birds lost the ability to fly that their predecessors had, according to a study published in the journalPNAS.
You can’t have everything in life, and for many seabirds, which feed on fish and other organisms in the ocean, doing well underwater is far more important than flying with ease. According to biomechanical models, wings designed for diving generatelarge energy losses when used in flightso that, at the evolutionary level, a species would have to “choose” between flying or swimming. To demonstrate this hypothesis, a group of scientists from the University of Manitoba (Canada) has studied the energy costs of both activities in thearao de Brünnich (Uria lomvia) a bird that propels itself with its wings into the water to feed itself and that can also fly, although not very efficiently. “Guillemots are terrible fliers,” explains Kyle Elliott, one of the authors. “They flap their wings too fast, and they are very bad at landing.”
The results revealed that these birds expend more energy per minute of flight than any other species studied so far. Specifically, its energy loss is up to 31 times the amount used at rest, when the rates of other vertebrates when making a great effort do not exceed 25 times.
On the other hand, although guillemots are more efficient in the water, this species spends much more energy diving than other penguins of the same size, which indicates that for the latter, the loss of flight capacity increased their energy efficiency by Water. According to the researchers, these results make sense, sincethe shape of the wings is different depending on the functionfor which they are designed. “If the guillemot’s wing were stubbier, swimming would be easier, since a short wing creates less friction with the water. However, in that case flying would be almost impossible, since a short wing makes it difficult to stay in the air ”, they conclude.
