Sunday, 28 April 2013

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

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

Feathers that cover birds are grouped in sets, both left and right side, and each of these sets fill a role.  
While some feathers form the contours of the body;  some, such as the flight feathers of the wing and tail, 
carry out a function.  The purpose of some feathers is to insulate, waterproof, and protect the body.

Feathers overlap each other like shingles on a roof.  Imagine the forward motion of a bird flying or swimming and being protected from that force by the overlapping of feathers.  Each feather and feather group is purposeful, structured, and arranged in an organized manner.  Not one feather exits on a bird in a random manner. . . everything in nature is structured as the organized feather tracts on a supermarket chicken indicates.

Why is this important to the bird artist?  Once the bird artist knows the basics of the skeleton and the sets of feathers inherent to all birds, each species' behavior can be observed and researched to perceive proportion, shape, behavior, and pose.  The goal is to create art . . . not a specimen.  

Below is a clarified and labeled drawing of a wild turkey in flight.

Turkey Bookends
7"H 16"W 7"D

All sculpture and drawings - copyright Sandy Scott

Wednesday, 24 April 2013

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

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

While most birds, like the magpie shown at right, have predictable tail flight feather and covert sets, there are a few with unique tails.  

The peacock's (related to pheasants) tail or "train" is not the 
tail flight feathers but the upper tail covert feathers . . . they sport an eye-like pattern.

Roosters have a profusion of structured, decorative tail feathers that do not fall under any specific tail-shape category.
Why is this important to the bird artist?  The bird artist must not only know how the skeleton is arranged and how it articulates, but where the feather groups and sets originate . . . their size, shape. proportion, and function. 

Shade of Paradise 
13"H 23"W 11"D

Crowing Rooster II - wall hanging
22"H 14"W 8"D

Above is a picture of our bantam-cross rooster . . . beautiful, tiny, and mean!
Photo, copyright Sandy Scott

Sunday, 21 April 2013

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

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

The bird's tail is actually a combination of left and right tail feathers.  One side cannot be spread without  the other spreading also but each side can move up and down independently.  Because of the two sides, there are always an even number of tail feathers.

The bird's tail is shaped differently depending on the species and how nature intended the bird to live and eat:  
The function of the tail is braking, steering, balance, aerodynamic lift, display, and signaling.

Below is an illustration showing several basic tail shapes for different bird species: 
                  1.  Square - starling or nuthatch             5.  Pintail - duck
                  2.  Cleft - Finch                                       6.  Wedge - raven
                  3.  Deep forked - tern or swallow            7.  Fantail - cuckoo
                  4.  Spiked feathers - woodpecker           8.  Elongated center feathers - bee-eater  

There are also variations, such as rounded (crow), pointed (mourning dove),
graduated (magpie), and several unique . . . such as roosters, peafowl, etc. 

Below is a recent sculpture of a Fantailed Pigeon . . . pigeons are in the dove family of birds.

Hearts Entwined 
12"H 22"L 11"D
Copyright - Sandy Scott

Below, detail . . . Hearts Entwined
All drawings and sculpture, copyright - Sandy Scott

Wednesday, 17 April 2013

#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

Sunday, 14 April 2013

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

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

Sculptors who use the human or quadruped figure as a subject, concentrate their studies on not only the skeleton, but the muscles as well.  Bird sculptors are an exception and although they must understand the skeleton and body shapes and masses . . .  muscles and their form are of little importance to the bird artist as birds are covered with feathers.  

The bird artist must know the feathers that cover birds are grouped in sets and they originate from the skin in organized sets, groups, tracts and from a definite region.   There is nothing random in nature . . . feathers do not emerge form the bird in a random manner.

The feather sets are basic and every bird has the same groupings . . . from the tiny hummingbird to the gigantic albatross.  
Length, shape, size and number vary according to the bird's needs, but once you know the sets, you can adapt them to any species.  

Below, wing flight feathers are divided into 3 groups:  
Primaries, secondaries, and tertials. In addition, every bird has the following: Scapulars, alula, and coverts.  

Copyright - Sandy Scott

Below and above . . . the tertials are a continuation of, moving inward from the secondaries.
The scapulars attach to the shoulder area, overlap the tertials and help streamline the wing-body intersection.  The alula group of feathers attach to the thumb and assist the bird in landing by reducing the stalling speed of the wing.  Wing coverts are arranged in rows and overlap like shingles on a roof.  The coverts, along with the wing bones, impart a definite shape and thickness to the wing's leading edge and protect the main flight feathers.

Copyright - Sandy Scott

Height of Land
12"H 23"W 15"D
Copyright - Sandy Scott

Wednesday, 10 April 2013

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

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

Most birds are designed for flight and flying demands a rigid airframe.   The bird's rib cage and backbone are fused together . . . only the neck, tail, and wings are flexible.  The spine of mammals - human and quadruped - is supple.  A bird's spine is rigid . . . 
if it were supple, the bird would lose control and could not fly. 

The bird's bones are hollow, light, and remarkably strong.  For instance, a pelican weighs twenty pounds and the skeleton weighs only twenty-three ounces.  Nature has sluffed off weight to enable flight.  

The skeleton of a bird can be summarized as follows:  
    1 - the skull, made up of fused bones  
    2 - the vertebral column; includes 13-25 neck vertebra, fused backbone vertebra, flexible tail vertebra   
    3 - the hip girdle which provides support for the legs and where the leg muscles attach  
    4 - the pygostyle, where the tail feathers attach  
    5 - the sternum or keel, which anchors the wing pectoral muscles of flying birds  
    6 - the wing, includes the humerus, radius/ulna, and hand which anchors the primary flight feathers  
    7 - the leg - includes the femur, tibia, tarsus, and toes  
    8 - the clavicle or wishbone, which keeps the wing joint and coracoid in position as the wing muscles 
         pull downward.

A bird's entire body, except is bill and feet, is usually covered with feathers.  Why is the skeleton important to the bird sculptor?  The bird sculptor must know how the bones are arranged, how they articulate, and the limitations of skeletal movement before attempting to define muscles and feather groups.  

Copyright - Sandy Scott

Below is an etching entitled Dominick - copyright Sandy Scott
The underlying skeleton can be seen above and is also illustrated in post #410

Sunday, 7 April 2013

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

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

Like humans and quadrupeds, birds are vertebrates . . . meaning they have a backbone.  Nature has designed just one pattern for all vertebrate mammals.  All mammals, humans, horses, dogs, bears, deer, cats, and interestingly, even giraffes have 7 neck vertebrae.  Birds, on the other hand, have a very flexible neck consisting of 13 - 25 neck vertebrae.

At the other end of the spinal column, humans have a coccyx, mammals have a tail, and birds have a pygostyle.  During the course of evolution, birds have gradually lost the part of the backbone that makes up the tail . . . the tail has been replaced by feathers that are attached to the pygostyle, which is actually a bone structure covered with muscle and flesh.  Look at the supermarket chicken on the right and you will see the pygostyle . . . colloquially known as the "pope's nose."  Upon examining the pygostyle, you will notice the holes on the fleshy shape where the tail feathers emerge and fan out.

Why is this important to the bird artist?   The bird artist must know how the skeleton is arranged, 
how it articulates, and where the tail feather group originates.

Comparison of vertebrates . . . human and quadruped above and bird below
Concept, after Elliot Goldfinger.

Copyright - Sandy Scott

Below is a drawing of a wild turkey.  The magnificent bird has 18 long, stiff tail feathers and a gobbler in full display, 
with tail feathers fanned, is one of nature's most exquisite visual gifts.

Copyright - Sandy Scott

Friday, 5 April 2013

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

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

The upper part of the bird's leg is the femur or thigh.  Below the femur is the tibia or drumstick.
The remaining structure below the drumstick makes up the foot of the bird; called the tarsus and the digits or toes.  

Below, is a drawing of a turkey's leg with the bones surrounded by muscles, tendons, flesh.  Unlike modeling the human or quadruped, the bird sculptor should be more concerned with the skeleton and how it articulates than the muscles, tendons, etc.  Next, the feather groupings and the region where they emerge simply must be known.

Below, is a drawing of a turkey from one of my sketch books.  The feather groupings and patterns are organized and understood . . . due to a realization of the underlying structure and anatomy.

Wednesday, 3 April 2013

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

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

The bird's leg is similar in structure to the human.  Many believe that a bird's knee bends backwards 
because they mistake the ankle for the knee.  As in man . . . a bird's knee bends forward.

The bird's knees and thighs are hidden under feathers . . . you don't see the bird's knee 
and the joint that appears to be the knee is actually the ankle.

Below is a drawing comparing the human leg with a bird's leg.
Scroll to the last blog and see how the bird's leg attaches to the skeleton.

Copyright - Sandy Scott

Below, is one of my favorite works entitled Hay Bay.  The sculpture depicts a live-sized Mallard pitching in for a landing.  Note the bend at the bird's ankle . . . the knee is hidden by feathers.

Hay Bay
19"H 25"W 14"D
Sandy Scott