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

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

Understanding the bird's anatomy takes the mystery out of drawing and modeling.  

The skeleton influences the surface appearance even though the bird is covered with feathers.
Identifying the bird's wrist establishes a point of reference . . . a landmark or waypoint . . . 

a unit of measure to determine wing shapes and proportions.  

All birds fall into a semblance of four basic wing shapes - see post 423, May 5, 2013.  

Identifying the wrist helps the artist establish proportion and pose.   

No waypoint is more important than the bird's wrist when modeling the folded or partially folded wing.  

By locating this boney waypoint, the sculptor can easily determine where the secondaries and primaries originate.  

Harbinger of Light

15"H 20"W 16"D

All sculpture and drawings - copyright Sandy Scott

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

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

A bird's feathers grow in sets and groups and the bird artist must know how both body groupings 

and flight feathers are arranged.  Feathers grow in tracks, in orderly rows, and overlap like shingles on a roof.  

Plumage patterns are organized in a similar manner across all species.

If there is a conflict between sculpting what you see - or think you see - as in a photo, video, or in the field . . . 

rely on what you know.  The goal of a sculptor is to UNDERSTAND what they are looking at.  

A sculptor must sculpt what they KNOW, while a painter paints what they see.

Above, are clarified drawings of a bird's most basic and simple forms.  

The sculptor should omit the unimportant and block in the essentials.

Major shapes, planes, and correct proportions, should be established first.

Below, is a recent sculpture of a Peregrine Falcon modeled life-sized.

My goal was to cause the viewer to feel speed and the beauty of flight by eliminating detail.

One does not see detail when animals are in motion.

A Peregrine reaches speeds of up to 200 miles per hour when hunting. 

Falcon Heart Humming

20"H 20"W 16"D

All sculpture and drawings - copyright Sandy Scott

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

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

An airplane has an engine and propeller to provide thrust and movement.  The bird has enormous pectoral muscles -  think of a chicken's white meat -  attached to its keel, which power twenty propellers, or ten primary feathers per wing, which twist and propel it through the air.






At right is a drawing of 3 of a bird's 10 primary flight feathers . . . the artist must know that each of the 10 individual primaries is shaped differently.  The outermost primaries - numbers 1  2 are narrower at the tips, thus creating "slots" necessary for flight maneuverability.  The primaries closest to the secondaries are shaped more like the secondary feathers.   

At right is a cross-section drawing of a wing:  Both an airplane and a bird can change the angle in which the shape moves through the air.  This adjustment is called the wing's angle of attack. . . see post # 424.  When an airplane comes in for a landing, the nose comes up allowing the shape and resistance of the fuselage to slow the airplane.  When the landing gear is lowered, creating more drag, it slows the airplane as it descends.  The pilot continues pulling the nose up, or increasing the angle of the wing's attack, until the wing stalls or stops flying, placing the machine on terra firma.  A bird is analogous to an airplane . . . it drops the backend of it's body, splays the tail feathers, and drops the legs to create drag,  thus permitting the flaring and stalling of the wings which results in a landing!

Below, is a clarified drawing of a hawk coming in for a landing.  Note, the wing's high angle of attack, the dropped body shape, the splayed tail feathers, and the lowered legs.  All elements slow the bird and as the wing angle increases, the wings stall and the bird lands.  Note, the pectoral muscles are  always directly under the wings.

Why is this information important to the bird artist?  Understanding wing shapes, attitude, 

and aerodynamics will open the door to breathing life into the artist's work.  the artist must 

realize that it is the superb shape of the bird's wing that causes the wonder of flight.

Below is an original, hand-tinted etching of mallards pitching in for a landing . . .

tail feathers flared, body angled, "gear" down, and wings angled high . . .

the ducks are slowing down to alight on a pond.

Mallards

7 1/4 x 8 1/4

All sculpture and drawings - copyright Sandy Scott

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

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

How many times have you sat in an airplane and marveled at the mystery of a ponderous machine taking you aloft? What could possibly make this enormous device fly?  The answer is a complex series of events, but if one word had to be used to describe why an airplane flies, that word would be SHAPE.  The SHAPE of the airplane's wing, like the SHAPE of the bird's wing when moved through the air, causes lift.

Drawing number 1 at right; note the leading edge of a wing's SHAPE is blunt and thick, which causes the moving wing to part the air more effectively.  The back or trailing edge of the wing thins dramatically to speed the wing through the air.

The SHAPE of the upper surface of the wing is more rounded and air moving over the top has more surface and distance to cover which creates low pressure.

The SHAPE of the underside of the wing is slightly concave and air has less distance to travel, therefore moving slower and causing high pressure.

Lift is produced as the high pressure on the under surface of the wing attempts to occupy the low pressure on the upper surface.


Drawing number 2 at right; if the wing is held at too high an angle of attack, the air cannot smoothly flow over the wing's surface.  An interruption or "burble" forms at the trailing edge of the wing, which causes loss of lift and the wing  stalls.

Airplanes and birds take off into or facing the wind because it expedites the air that must move over the wing surface to create lift.  They land into the wind as well because at slower landing speed, air must continue to move over the wing's surface.
The scientific term for the above is Bernoulli's Principle.

 Why is all of this important to the bird sculptor.
In two words: pose and gesture.
Principles of flight and the SHAPES involved are the same for airplanes as they are for birds.

Below is a sculpture entitled Hay Bay.
Knowledge of the wing and aerodynamics create the illusion of descending flight.

Hay Bay
19"H 25"W 14"D


All sculpture and drawings - copyright Sandy Scott

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

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

Wing shapes vary among birds, reflecting the adaptations they have made to different environments.  There are four basic wing shapes, and all birds fall into a semblance of one of the four configurations.  The size and shape of the wings give clues to how the bird lives:

   1.  Long, wide wings are used by soaring birds such as hawks, eagles, and
        ravens.  A wing is considered long when it exceeds the length of the
        bird's body.
   2.  Narrow and pointed wings are used by fast flying birds such as swallows,
        swifts, and many migratory birds such as ducks and geese.
   3.  Long and narrow wings are used by gliding birds such as albatrosses,
        gulls, terns, fulmars, and shearwaters.
   4.  Wide and rounded wings are used for short, fast, and quick-escape flight
        birds such as grouse, pheasants, pigeons, and owls.

The wings of birds do not all have the same shape and size, but all fall into one of the four basic categories.  The shape and size of the wings determines what style of flying a bird executes.  Wing shape is one of the primary ways to identify different species.

Below are illustrations of four different wings.  Each fall into one of the four wing shape categories.

Below is a drawing of a Canada Goose . . . the large bird is migratory and falls into the
basic wing shape of number 2.  However, the wing is also wide and can be considered
to fall into a slight semblance of wing shape number 1, even though it cannot soar. 

All sculpture and drawings - copyright Sandy Scott

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

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

A bird's wing feather sets are basic and every bird has the same groupings. 

Once the basics are understood, the artist can adapt them to any species.

Below is a drawing comparing the underside of the wing with the top of the wing.

  Birds have a set of feathers in the armpit region on the underside of the wing called the axillars. 

This group of fan shaped feathers help close the gap between inboard wing feathers and the body during flight.  

Note the various sets of coverts and structured underwing feather lining.

Why is knowledge regarding the wing and the feather groups important to the bird artist?
There is nothing random in nature, and the bird artist should know the feather groups
so well that the wing can be modeled at will from understanding and memory.

Below . . . Note the axillar group in the armpit region.

Mallard Rising
15"H 26"W 16"D

All sculpture and drawings - copyright Sandy Scott

#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

#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


All drawings and sculpture copyright Sandy Scott

#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

#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

#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

#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

#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

Copyright - Sandy Scott

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

#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.

#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