What is a bird

They have feathers, wings, two legs, and a bill. Less uniquely, they have a backbone, are warm-blooded, and lay eggs. All but a few birds can fly. Birds have much in common with reptiles, from which they have evolved. They share several skeletal characteristics, nucleated red blood cells, and their young develop in cleidoic eggs. The main difference is feathers, which are modified scales. Not only do feathers allow flight, they are insulated, more so than mammalian...

Birds and humans

Why are we so fascinated with birds From the earliest cave paintings and ceramic effigies of prehistoric humans to the present, we find close links between birds and ourselves. Those links are related to several things that draw us together (1) our fascination with and envy of the ability of birds to fly (2) the meat and eggs they provide us (3) their colorful plumage that we admire and often use to decorate our own attire (4) their down feathers that we use for insulation, and other feathers...

Avian migration and navigation

The Migration Path Albatross

Ornithologists typically think of migration in terms of the dramatic round-trip journeys undertaken by species that move between high and low latitudes. Even in birds, however, migrations of many types occur that vary in regularity of occurrence, duration, and distance covered. The theme that ties the various types of migration together is that they are all evolved adaptations to fluctuating environmental conditions that render some areas uninhabitable during some portion of the year. The...

Library Of Congress Cataloginginpublication Data

English Grzimek's animal life encyclopedia. 2nd ed. v. cm. Includes bibliographical references. Contents v. 1. Lower metazoans and lesser deuterosomes Neil Schlager, editor v. 2. Protostomes Neil Schlager, editor v. 3. Insects Neil Schlager, editor v. 4-5. Fishes I-II Neil Schlager, editor v. 6. Amphibians Neil Schlager, editor v. 7. Reptiles Neil Schlager, editor v. 8-11. Birds I-IV Donna Olendorf, editor v. 12-16. Mammals I-V Melissa C. McDade, editor v. 17....