#504 In the studio: Birds . . . classification

Start this series with post # 503, Feb. 5, 2014

Scientists have organized and classified birds into major groups called ORDERS.


Each order contains a number of entities called SPECIES.

Species refer to all the birds within an order that are like one another . . . robins, for instance, belong in one species, 
and are in the order passeriformes.

Since "arky", more than 1.5 million species of birds 
have existed on this planet . . . of these, approximately 
10,000 species have evolved and remain.

 BELOW, IS A LIST OF THE ORDERS OF BIRDS . . . (LIVING SPECIES)

             
                     1  Tinamiformes:  tinamous and rheas
                     2  Struthioniformes: ostriches
                     3  Casuariiformes:  cassowaries, emus, and kiwis
                     4  Galliformes:  gamebirds
                     5  Anseriformes:  waterfowl
                     6  Sphenisciformes: penguins 
                     7  Gaviiformes:  loons (divers)
                     8  Podicipediformes:  grebes
                     9  Procellariiformes:  albatrosses and petrels
                   10  Phoenicopteriformes:  flamingos
                   11  Ciconiiformes:  herons and allies
                   12  Pelecaniformes:  pelican and allies 
                   13  Falconiformes: birds of prey
                   14  Charadriiformes:  gulls, plovers and allies 
                   15  Gruiformes:  cranes and allies
                   16  Opisthocomiformes:  hoatzin
                   17  Charadriiformes: waders and shorebirds 
                   18  Pteroclidiformes:  sandgrouse
                   19  Columbiformes:  pigeons
                   20  Psittaciformes:  parrots and cockatoos
                   21  Musophagiformes:  Turacos
                   22  Cuculiformes:  cuckoos
                   23  Strigiformes: owls
                   24  Caprimulgiformes:  nightjars and allies 
                   25  Apodiformes:  hummingbirds and swifts
                   26  Caliiformes:  mousebirds
                   27  Trogoniformes:  trogons 
                   28  Coraciiformes:  kingfishers and allies
                   29  Bucerotiformes:  hornbills and hoopoes
                   30  Piciformes:  woodpeckers and allies

                   31  Passeriformes:  perching birds, song birds, ravens, and allies
        

          

Each bird on the planet falls into one of the ORDERS and is arranged in a sequence that indicates its closest relative.  Outward appearance does not always place birds in the same ORDER as ornithologists look beyond appearance and rely on factors such as anatomy, skeletal structure, DNA analysis, etc.  A complete list of all birds on the planet can be found online by going to Wikipedia: List of Birds. The different species in each ORDER can be found online and in various
field guides which will be discussed in the next post.  Scientists, however, continue to disagree as to the exact 
number of birds in existence as well as to what ORDER some should be placed. 

The highest ranked order, the passeriformes, or perching birds are the most adaptable and are 
considered the highest evolved . . .  the lowest ranked are the flightless ostriches and rheas.  

Over half of all birds on earth belong to the passeriformes order.  Some scientists believe that early in the 
evolutionary process, birds split into two diverse groups.  The first, and much smaller group comprised 
ratites, tinamous, waterfowl, and pheasants.  The second group included all the other avian orders.

Below, is a drawing of an ostrich and a image of a raven sculpture.  
Most scientists consider flightless bird the lowest ranked order 
on the evolutionary classification chart.  The passerines - which includes corvids like 
the raven - is considered the highest evolved and most adaptable.

Black Magic
23"H 17"W 17"D 

Following the Jurassic Period, dinosaurs became extinct at the end of the Cretaceous Period . . .  flowering plants flourished and, released from competition with dinosaurs, birds (and mammals)  occupied some of the niches of the bipedal dinosaur.  Under these conditions, birds thrived and diversified.  

The function of classification is to make sense of the diversity of species by grouping together related forms.  

This diversity is the result of rapid evolutionary change during the past 50 million years.

To avoid confusion across languages, Latin names are used in bird classification, as they are for all other organisms.  Closely related species are grouped in one genus, closely related genera are grouped in 

one family, closely related families are grouped in one order, and so on.          

Since the late 20th century,  fossil discoveries in China and DNA studies continue to present 

controversy among  scientists as to the distantly related ancestors of the modern bird.
Technically, birds are "avian dinosaurs" and the debate continues as to whether they evolved from a bird-like reptile.  

Below, discoveries, analysis, and debate will continue among scientists, but for now . . .
"arky" remains the universally recognized transitional fossil - or link - between dinosaurs and the modern bird.  


Below is a drawing of "arky" and a photo of the fossil found in 1861 . . . see the previous post for more information.

Blog, text, photos, and sculpture . . . © Sandy Scott and Trish Smith

#503 In the studio: Birds . . . evolution and anatomy

BIRD EVOLUTION AND ANATOMY

Birds appeared more than 150 million years ago, during the Jurassic or possibly the Triassic period.
The recent discovery of vast beds of fossil birds and "feathered dinosaurs"  in deposits in northeast China
and central Asia has opened argument about whether birds descended from dinosaurs or earlier
 archosaurs but also clarified an ongoing question:  Birds and two-legged creatures such as
the carnivore, Tyannosaurus rex, are on the same branch of the evolutionary tree.

The earliest known bird was the Archaeopteryz - pronounced arky-OP-tuh-ricks - the word means "ancient wing" in Greek.  A fossil discovered in Bavaria in 1861 shows that the creature who grew to the size of a crow, had feathers, claws, and other features that scientists think is the link to modern birds.   Six specimens of "arky" have been found . . .
all in limestones in southern Germany and all dated between 200 and 140 million years ago.

Below, is a photo of Archaeopteryz . . . "arky" for short.

Although "arky" had many unmistakable bird features, much of its skeleton is akin to those of reptiles.
Scientists think a bird's scaly legs are the last reminders of a reptilian ancestor and that feathers originated as
reptilian scales . . . feathers are made from the same horny substance of which fingernails are made.   

Feathers - not flight - set birds apart from other animals. . . many species, such as ostrich, have evolved with an inability to fly.  The evolution of powered flight required major skeletal modifications to change its early gliding wing movement to flapping flight.  The small,  two-legged, carnivorous dinosaur designed for a life of gliding from tree to tree in a gloomy Jurassic jungle evolved into today's modern bird and Archaeopteryz is the missing link.

Most, but not all birds fly.  The bones are light but remarkably strong, and some contain air sacs connected to the lungs.  Below, is a drawing of a bird skeleton and illustrates a number of modifications that make flight possible.
(1): Heavy teeth have been replaced by a light bill

(2): The bones of the skull are thin.

(3) and (4): The bones of the wings and legs are composed of thin-walled, honey-combed  tubes.
Nature has sluffed off weight to enable flight.

Although the information presented in this post is current . . .  as new discoveries are made,

both in the field and with DNA, scientists will continue to fine-tune,
fill in the details, provide a more complete picture, and debate the evolution of birds.

The fact remains that "arky" was unique for it possessed feathers.
The development of feathers was one of the crucial steps in the evolution of birds.


Blog, text, photos, drawings, and sculpture . . . © Sandy Scott and Trish Smith