. The bird, its form and function. Birds. 360 The Bird each foothold as secure as if its feet were vacuum- cupped. In the swallows the feet are very small, having fallen into disuse with the great increase of the power of flight. Orioles and weaver-birds make occasional use of their feet to hold a strand of grass or string which they are weaving with their beaks into their elaborate nests, and certain flycatchers pounce upon and hold their insect. Fig. 28S.—Swallow, showing small size of feet- prey as an owl grips a bird, or a jay clings to a nut; but with the exception of a few such cases, th
. The bird, its form and function. Birds. 360 The Bird each foothold as secure as if its feet were vacuum- cupped. In the swallows the feet are very small, having fallen into disuse with the great increase of the power of flight. Orioles and weaver-birds make occasional use of their feet to hold a strand of grass or string which they are weaving with their beaks into their elaborate nests, and certain flycatchers pounce upon and hold their insect. Fig. 28S.—Swallow, showing small size of feet- prey as an owl grips a bird, or a jay clings to a nut; but with the exception of a few such cases, the feet of perching birds serve principally the function of locomotion. As variation in habitat or haunt depends so much upon the power of locomotion, it will not be out of place to mention here, in rather more detail than usual, a splendid examjDle of adaptive radiation which we can all verifj^ for ourseh'es. There is no more wonderful fact in Nature than the way. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Beebe, William, 1877-1962. New York, Holt
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbirds, bookyear1906
