#418 In the studio: Bird anatomy, con't .

Please start this bird anatomy series with post #403, March 10.

Most birds have 6 pair or 12 tail feathers . . . some birds have less: hummingbirds, swifts, and cuckoos have 5 pair or 10 tail feathers; and a few species have more . . . turkey, grouse, and pheasant have 9 pair or 18; and a white pelican has 12 pair of tail feathers or 24.  It's important to remember that all birds have an even number of tail feathers on each side of the body centerline; and the pairs originate from the pygostyle at the end of the spinal column . . . and all tail feathers, whether closed or fanned, must radiate from this central point of insertion.

The tail contains 3 feather areas:  The tail feathers, called retrices; the upper tail coverts; and the under tail coverts. The coverts lie over the base of the tail feathers, their function is to protect, or cover  the retrices and smooth the airflow over them.   

Why is this knowledge important to the bird sculptor?  Feather groups and sets are structured . . . not random.  
Knowing the bird's skeleton enables the artist to determine where the feather groups originate. 

Copyright - Sandy Scott

When modeling a large, over life-sized bird monument, such as an eagle . . . 
knowing the tail feather groups as well as the wing feather groups and all others, are of particular importance. 

Noble Eagle - in clay

22' wingspan