CHAPTER VII 



ADAPTATION TO HAUNTS 



§ I. Arboreal Life. § 2. Aquatic Life. § 3. Adaptations to Swamps. 

 § 4. Adaptations to Desert and Steppe. § 5. Mountain Birds. 

 § 6. Moorland Birds. § 7. Birds of the Sea Cliffs. § 8. Birds in 

 other Haunts. § 9. Protective Coloration. 



Living, as Professor Geddes has remarked, is a continual 

 adjustment between the Organism acting or functioning 

 on its environment, and the Environment acting on the 



0-f-e 



organism : As the direct, or, more probably, 



E-f-o. 



indirect result of the twofold process there have evolved 



permanent adaptations of the organism to its environment. 



In this chapter we have been particularly indebted to Dr. 



Hilzheimer (1913). 



§ I. Arboreal Life 



It is highly probable that primitive birds were arboreal ; 

 it is certain that many birds of to-day have that habitat. 

 A common arboreal adaptation is to have strong sharp 

 claws on the toes, as in the Tree-Creeper which runs up the 

 tree-stem in a spiral, helped in some measure by its stiff- 

 pointed tail-feathers. By an alternation of jumps and 

 grips the nearly related Wall-Creeper ascends a vertical 

 cliff- face, catching spiders as it goes. Much curved claws 

 are better suited for firm gripping than for rapid climbing, 

 and the relative position of the toes, e.g. two forwards and 

 two backwards in woodpeckers, may make the grip still 

 better. The stiffening of the terminal part of the shaft of 

 some of the tail feathers is seen in woodpeckers and some 



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