. The bird, its form and function . e of these intelligent birds requires. The crow or the raven is an excellent example of amodern bird with a remarkably generalized diet, in strikingcontrast to those birds whose bills show them to be fittedfor feeding only on some strictly defined food. Withhis strong, ample beak the crow can dig up recentlyplanted corn, or crack the hard shells of acorns; he en-joys stealing the eggs and the young birds of thrushes,orioles, sparrows, warblers, and quail, and I have seena crow chase, capture, and carry off a half-dozen wild Mal-lard ducklings in one morning!
. The bird, its form and function . e of these intelligent birds requires. The crow or the raven is an excellent example of amodern bird with a remarkably generalized diet, in strikingcontrast to those birds whose bills show them to be fittedfor feeding only on some strictly defined food. Withhis strong, ample beak the crow can dig up recentlyplanted corn, or crack the hard shells of acorns; he en-joys stealing the eggs and the young birds of thrushes,orioles, sparrows, warblers, and quail, and I have seena crow chase, capture, and carry off a half-dozen wild Mal-lard ducklings in one morning! These birds are, in ad-dition, able to capture insects of all kinds, besides pick-ing berries, and ducking their heads under water in questof the shrimps which live in tide-pools. In short, theirbill serves them well in procuring many kinds of food,from earth, water, or tree; as well as in carr3dng greatquantities of sticks, which they use in the constructionof their nests. These birds are so skilful with their Beaks and Bills 227. Fig. 1G4.—Beak of (iannet. Ml |H 1 Hjj^^^ ■ ^^^^■^^^ ^^^^-- -. Fig. 1().5.—Beak of closely related, but procuring food in different ways. 228 The Bird beaks that a new trick is learned in a very short captivity a crow, when it thinks no one is watching,will often take a morsel of food, thrust it beneath a pieceof sod, and cover it ii{) with grass, almost with onemotion of the beak. Functional or adaptive radiation is beautifully il-lustrated by the beak of a gannet, cormorant, snake-bird, and pelican—birds which are closely related toone another structurally, also having in common a fishdiet, swallowing their prey whole. The gannets beakis thick and \ery strong, and along the inner edge is aseries of fine serrations pointing backward. The birddives, from a great height, into the water and seizes thefish in a grip of steel. The upper mandible of the cor-morant is furnished with a large, sharp hook, with whichthe bird
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Keywords: ., bookauthorbeebewil, bookcentury1900, bookdecade1900, bookyear1906
