ORNITHOLOGY

ORNITHOLOGY, the branch of natural history that deals with the systematic study of birds, began in America in the eighteenth century. The British naturalist Mark Catesby was the first individual to thoroughly document the flora and fauna of the New World. His illustrated, two-volume work, Natural History of Carolina, Florida, and the Bahama Islands (1731–1743), included descriptions of more than a hundred North American birds.

Early Studies

In the period surrounding the Revolutionary War, Philadelphia served as an important center for American natural history. A pivotal figure here was William Bartram, whose Travels through North and South Carolina, Georgia, East and West Florida (1791) contained a list of 215 avian species. Bartram's exuberant descriptions of the southeastern landscape inspired many Americans to embrace the study of natural history and to regularly visit his home for guidance. They also patronized the Philadelphia museum of Charles Willson Peale, the American artist and naturalist who used a combination of European taxidermy methods and his own techniques to preserve specimens, thereby making possible the creation of permanent bird skin collections. The Scottish immigrant Alexander Wilson frequented both locations, and at Bartram's persistent urging, began an ambitious project to describe and illustrate every North American bird species. Wilson spent nearly a decade scouring the countryside to find the material needed for his multivolume American Ornithology (1808–1814), which treated more than 264 species, including forty-eight that were new to science.

Wilson's book was soon eclipsed by John James Audubon's masterful Birds of America (1827–1838), which contained 435 hand-colored, life-sized engravings. Audubon was a brilliant artist, though he sometimes sacrificed scientific accuracy for aesthetic effect. Nevertheless, his reputation as America's foremost bird illustrator remains secure, his exquisite drawings continue to be widely reproduced, and his name has been permanently memorialized in the National Audubon Society.

Institutionalization

The generation of ornithologists that followed Wilson and Audubon were more technical in orientation, and as a result, their publications became less accessible to the general public. Increasingly, American ornithology began to coalesce into a scientific discipline unified by the goal of providing a precise inventory of the nation's birds. State natural history surveys, western exploring expeditions, and individual collectors provided the raw material for this enterprise. By the middle of the nineteenth century, the Academy of Natural Sciences in Philadelphia, the Museum of Comparative Zoology at Harvard, the Smithsonian Institution in Washington, and other public and private museums were amassing the large study collections ornithologists needed to conduct their taxonomic research. Later in the century, these pioneering institutions were joined by the American Museum of Natural History in New York, the Field Columbian Museum of Chicago, and the Carnegie Museum in Pittsburgh. Curatorships at these and other museums provided most of the few paid positions available to ornithologists until the early twentieth century.

The establishment of societies devoted to bird study marked another important stage in the institutionalization of American ornithology. In 1873 a small group of ornithologists associated with William Brewster, of Cambridge, Massachusetts, established the first bird study organization in the United States: the Nuttall Ornithological Club. A decade later this society became the springboard for the creation of the American Ornithologists' Union (AOU), an organization dominated by technically oriented ornithologists. By 1900, there were dozens of ornithological societies in the United States, including not only the Nuttall Club and the AOU, but also the Wilson Ornithological Club, the Cooper Ornithological Club, and the Delaware Valley Ornithological Club. Many of these organizations remain active today.

Throughout the second half of the nineteenth century, scientific ornithologists continued their struggle to produce a single authoritative inventory of the continent's avifauna, down to the level of species and subspecies (the latter are those geographic races delimited by small average morphological differences in specimens). A smaller number of economic ornithologists, on the other hand, studied the diets of birds. Through stomach content analysis and observation, they began to document the role that birds, especially songbirds, played in the control of insect pests. Their data became important in the wildlife conservation movement that emerged at the end of the nineteenth century.

Birdwatching and the Audubon Movement

Ornithologists played a crucial role in the movement to gain protection for birds, especially from commercial hunting for food and the millinery trade. In 1905, a series of state Audubon societies joined in a loose confederation, the National Association of Audubon Societies for the Protection of Wild Birds and Animals (later renamed the National Audubon Society). Audubon societies lobbied for bird protection laws, promoted the establishment of bird sanctuaries, and developed public education campaigns stressing the beauty and economic utility of birds.

The beginning of birdwatching also dates from this period. While the transcendental writer Henry David Thoreau might have been the first American to devote considerable time observing birds in the wild, few followed his lead until the beginning of the twentieth century. By then, the development of inexpensive field glasses, the publication of the first portable field guides, a decline in the average work week, the diffusion of romantic sensibilities, and the prodding of Audubon officials enticed the public to embrace birdwatching as an important leisure activity. The publication of Roger Tory Peterson's Field Guide to the Birds (1934) provided further impetus for this hobby, which today tens of millions of Americans regularly enjoy.

Recent Trends

During the first half of the twentieth century, scientific ornithology finally began to broaden from its previous preoccupation with the classification and description of North American birds. The development of graduate programs in ornithology, ecology, and evolutionary biology played an important role in diversifying ornithological research. By the 1920s and 1930s, Cornell, Berkeley, and Michigan had active graduate programs in these areas, and the number continued to rise into the middle of the twentieth century. University-trained ornithologists were more likely to pursue ecological, behavioral, and physiological studies than their largely self-trained nineteenth-century counterparts. They found employment in a variety of positions, ranging from museum curators and researchers to conservationists and wildlife managers. Those ornithologists who remained interested in the classification of birds have become increasingly global in orientation, and they often conduct their research using the latest scientific techniques. Both of these trends are exemplified in the research of Charles Sibley and Jon Ahlquist, who in the 1970s and 1980s used DNA hybridization to produce a new classification of the birds of the world. Because birds have been so thoroughly studied, ornithologists have also played an important role in documenting the biodiversity crisis—the worldwide decline of wildlife brought on by human-induced changes to the biosphere.

BIBLIOGRAPHY

Allen, Elsa G., The History of American Ornithology before Audubon. Transactions of the American Philosophical Society, n.s. 41, no. 3. Philadelphia: American Philosophical Society, 1951.

Barrow, Mark V., Jr. A Passion for Birds: American Ornithology after Audubon. Princeton, N.J.: Princeton University Press, 1998.

Davis, William E., and Jerome A. Jackson, ed., Contributions to the History of North American Ornithology. 2 vols. Cambridge, Mass.: Nuttall Ornithological Club, 1995–2000.

Gibbons, Felton, and Deborah Strom. Neighbors to the Birds: A History of Birdwatching in America. New York: Norton, 1988.

Mark V.BarrowJr.

See alsoAudubon Society .

Ornithology

Ornithology is the branch of zoology that deals with the study of birds. Birds are any organisms in the class Aves. They are warm-blooded (or homoio-thermic) vertebrates that have feathers covering their body; forelimbs modified into wings; stouter hindlimbs used for walking, swimming, or perching; scaly legs and feet; jaws reduced to a toothless beak; and a four-chambered heart. Birds lay hard-shelled eggs from which their young hatch. Major subject areas in ornithology include: anatomy, physiology, behavior, ecology, evolution, and classification and systematics.

Birds evolved from a group of reptiles known as the dinosaurs (order Dinosauria), which first appeared during the late Triassic period (which ended about 210 million years ago). The earliest bird known in the fossil record is Archaeopteryx, from the mid-Jurassic period about 160 million years ago. These extremely early birds had many typical avian characteristics, such as feathers and a horny beak, and were very likely warm-blooded, but they also had reptilian features, such as teeth. In fact, modern birds and dinosaurs still have many characteristics in common, and some biologists and paleontologists believe that birds should be viewed, and classified, as “living dinosaurs.”

There are 27 orders of birds, divided into about 166 families, and containing about 9,000 living species. Some prominent families from the Americas include the Gaviidae (loons), Podicipedidae (grebes), Pelecanidae (pelicans), Phalacrocoracidae (cormorants), Anatidae (swans, geese, ducks, mergansers), Cathartidae (vultures), Accipitridae (hawks, eagles), Falconidae (falcons), Tetraonidae (grouse, ptarmigan), Phasianidae (quail, pheasants), Ardeidae (herons, bitterns), Rallidae (rails, coots), Charadriidae (plovers, turnstones), Scolopacidae (sandpipers), Laridae (gulls, terns), Columbidae (pigeons, doves), Strigidae (owls), Trochilidae (hummingbirds), Psittacidae (parrots, macaws), Picidae (woodpeckers), Tyrannidae (flycatchers), Hirundinidae (swallows), Corvidae (jays, crows, raven), Paridae (chickadees, titmice), Troglodytidae (wrens), Turdidae (thrushes, bluebirds),

Sturnidae (starlings), Vireonidae (vireos), Parulidae (woodwarblers), Icteridae (blackbirds, orioles), and Fringillidae (grosbeaks, finches, sparrows).

Avian anatomy changes remarkably during development, from the relatively simple structures of the fertilized egg, to the much more complex adult form. Anatomy is also extremely variable among species. Size alone ranges from flightless ostriches weighing up to 330 lb (150 kg), to tiny hummingbirds weighing only 0.08 oz (2.25 g). Perhaps the most distinguishing anatomical characteristic of birds is their feathers, which provide insulation against the loss of body heat, and a broad, yet light, wing and tail surface for flight. The forelimbs of birds are highly modified as wings, especially through the extension of their “fingers” into an airfoil surface for active and/or gliding flight (a few species, such as the ostrich and emu, have secondarily lost the power of flight). Other important anatomical adaptations for flying include the large breast muscles that are used to power flight, the large keeled sternum (or breastbone) to which the flight muscles attach, and the hollow bones and extensive air-sacs of most species of birds. Some birds have extraordinarily light bodies for their size—the magnificent frigatebird (Fregata magnificens ) has a wingspan of 7 ft (2 m), but its skeleton weighs only 4 oz (113 g), less than the weight of its feathers.

Birds lay eggs with a hard shell that contains a fertilized embryo. In most species, the eggs are laid into a nest constructed by one or both of the parents, and the eggs are incubated by the parents. The newly hatched young of most bird species are born in a relatively early stage of development, and are unfeathered, ungainly, and virtually helpless. These almost incompetent young must be fed and otherwise tended by their parents for some time, until they finish development and learn to fly and forage for themselves. The young of some other species are more developed when born, and may be capable of immediately leaving the nest to live a semi-independent, or even fully independent life.

A distinguishing element of avian physiology is homoiothermy, or metabolic activity that maintains the body temperature within a narrow, warm range optimized for muscular functions and enzyme efficiency. (Mammals and some other vertebrates are also warm-blooded.) Homoiothermy is a crucial physiological trait that allows almost all bird species to have an extremely active lifestyle. It also allows some species to live year-round in cold environments.

One of the most notable elements of avian behavior is their use of song to proclaim a breeding territory, and other distinct sounds to organize their social system, keep flocks together, warn other individuals of predators, and for other kinds of communication. Some other classes of animals are also rather vocal, particularly many mammals, but not to the same degree that most birds are. Some birds are also quite intelligent, second in this regard only to mammals. (Actually, corvids such as the raven Corvus corax are more intelligent than most species of mammals.) Another notable element of avian behavior is the habit of many species to undertake long-distance migrations between their breeding and wintering habitats. The most extensive migrations are made by the arctic tern (Sterna paradisaea ), some of whom breed at the most northerly limits of land on the northern tips of Greenland and Ellesmere Island, and then migrate to spend their winter foraging in Antarctic waters.

Ornithology

Ornithology is the branch of zoology that deals with the study of birds . Birds are any organisms in the class Aves. They are warm-blooded (or homoiothermic) vertebrates that have feathers covering their body; forelimbs modified into wings; stouter hindlimbs used for walking, swimming, or perching; scaly legs and feet; jaws reduced to a toothless beak; and a four-chambered heart . Birds lay hard-shelled eggs from which their young hatch. Major subject areas in ornithology include: anatomy , physiology , behavior , ecology , evolution , and classification and systematics.

Birds evolved from a group of reptiles known as the dinosaurs (order Dinosauria), which first appeared during the late Triassic period (which ended about 210 million years ago). The earliest bird known in the fossil record is Archaeopteryx, from the mid-Jurassic period about 160 million years ago. These extremely early birds had many typical avian characteristics, such as feathers and a horny beak, and were very likely warm-blooded, but they also had reptilian features, such as teeth. In fact, modern birds and dinosaurs still have many characteristics in common, and some biologists and paleontologists believe that birds should be viewed, and classified, as "living dinosaurs."

There are 27 orders of birds, divided into about 166 families, and containing about 9,000 living species . Some prominent families from the Americas include the Gaviidae (loons ), Podicipedidae (grebes ), Pelecanidae (pelicans ), Phalacrocoracidae (cormorants ), Anatidae (swans , geese , ducks , mergansers), Cathartidae (vultures ), Accipitridae (hawks , eagles ), Falconidae (falcons ), Tetraonidae (grouse , ptarmigan), Phasianidae (quail , pheasants ), Ardeidae (herons , bitterns ), Rallidae
(rails , coots), Charadriidae (plovers , turnstones), Scolopacidae (sandpipers ), Laridae (gulls , terns ), Columbidae (pigeons, doves), Strigidae (owls ), Trochilidae (hummingbirds ), Psittacidae (parrots , macaws), Picidae (woodpeckers ), Tyrannidae (flycatchers), Hirundinidae (swallows), Corvidae (jays, crows, raven), Paridae (chickadees, titmice), Troglodytidae (wrens ), Turdidae (thrushes , bluebirds ), Sturnidae (starlings ), Vireonidae (vireos ), Parulidae (wood warblers ), Icteridae (blackbirds , orioles ), and Fringillidae (grosbeaks, finches , sparrows).

Avian anatomy changes remarkably during development, from the relatively simple structures of the fertilized egg, to the much more complex adult form. Anatomy is also extremely variable among species. Size alone ranges from flightless ostriches weighing up to 330 lb (150 kg), to tiny hummingbirds weighing only 0.08 oz (2.25 g). Perhaps the most distinguishing anatomical characteristic of birds is their feathers, which provide insulation against the loss of body heat, and a broad, yet light, wing and tail surface for flight. The forelimbs of birds are highly modified as wings, especially through the extension of their "fingers" into an airfoil surface for active and/or gliding flight (a few species, such as the ostrich and emu, have secondarily lost the power of flight). Other important anatomical adaptations for flying include the large breast muscles that are used to power flight, the large keeled sternum (or breastbone) to which the flight muscles attach, and the hollow bones and extensive air-sacs of most species of birds. Some birds have extraordinarily light bodies for their size—the magnificent frigatebird (Fregata magnificens) has a wingspan of 7 ft (2 m), but its skeleton weighs only 4 oz (113 g), less than the weight of its feathers.

Birds lay eggs with a hard shell that contain a fertilized embryo. In most species, the eggs are laid into a nest constructed by one or both of the parents, and the eggs are incubated by the parents. The newly hatched young of most bird species are born in a relatively early stage of development, and are unfeathered, ungainly, and virtually helpless. These almost incompetent young must be fed and otherwise tended by their parents for some time, until they finish development and learn to fly and forage for themselves. The young of some other species are more developed when born, and may be capable of immediately leaving the nest to live a semi-independent, or even fully independent life.

A distinguishing element of avian physiology is homoiothermy, or metabolic activity that maintains the body temperature within a narrow, warm range optimized for muscular functions and enzyme efficiency. (Mammals and some other vertebrates are also warm-blooded.) Homoiothermy is a crucial physiological trait that allows almost all bird species to have an extremely active lifestyle. It also allows some species to live year-round in cold environments.

One of the most notable elements of avian behavior is their use of song to proclaim a breeding territory, and other distinct sounds to organize their social system, keep flocks together, warn other individuals of predators, and for other kinds of communication. Some other classes of animals are also rather vocal, particularly many mammals, but not to the same degree that most birds are. Some birds are also quite intelligent, second in this regard only to mammals. (Actually, corvids such as the raven Corvus corax are more intelligent than most species of mammals.) Another notable element of avian behavior is the habit of many species to undertake long-distance migrations between their breeding and wintering habitats. The most extensive migrations are made by the arctic tern (Sterna paradisaea), some of whom breed at the most northerly limits of land on the northern tips of Greenland and Ellesmere Island, and then migrate to spend their winter foraging in Antarctic waters.

Ornithology

Ornithology is the branch of zoology that deals with birds. It includes the study of the development, anatomy (structure), physiology (function), behavior, classification, genetics, and ecology of birds, among other things. Scientists believe that they know more about birds than any other group of organisms.

Named after the Greek word for birds, ornithology is the scientific study of birds. The Greek philosopher, Aristotle (384–322 b.c.), was very interested in all aspects of biology and wrote a great deal on birds. He listed about 40 species and described their habits, migration (movement from one place to another), and relationship to the environment. Many consider the thirteenth-century emperor, Frederick II (1194–1250), as the first real ornithologist because of his book, On the Art of Hunting with Birds. Although Frederick II was a falconer and wrote his book about using falcons to catch prey, his work was also a serious, scientific account of the habits and the structure of many types of birds. Most books written on birds during his time focused on the practical aspects of birds, such as falconry or game-bird management. However, the fifteenth-century discovery of the Americas eventually gave students of the natural world a huge number of new and sometimes wildly different and exotic birds to describe and understand. By the 1750s, birds were included in all classification systems, and by the end of the next century, their place in the world's evolutionary history was becoming understood. However, until about 1900, most bird studies still were concerned only with classifying and describing them. Soon after the beginning of the twentieth century, universities began to grant degrees in ornithology, and professional ornithologists came on the scene. As a result, the twentieth century saw an emphasis on further understanding bird anatomy and behavior as well as their role in the overall balance of life (ecology).

There are nearly 9,000 species of birds, and ornithologists have decided that what most distinguishes an organism as a bird is not its ability to fly, but rather its feathers. Birds are vertebrates (animals with a backbone) that have feathers covering their body, and have forelimbs that are modified into wings. They are endothermic (warm-blooded; maintain an internal temperature despite their environment) and many parts of their bodies have adapted to their ability to fly. For example, they have large, powerful breast muscles, a streamlined shape, and hollow bones (since weight is a critical factor in flying). Birds lay eggs, have an extremely active life cycle, and use song and sounds for many different reasons, such as a warning, to mark territory, and to show dominance or attract a mate. Birds are very diverse. There are 27 orders of birds in the class Aves, divided into about 166 families that contain about 9,000 species. Some migrate extremely long distances, while others stay in the same habitat. They can vary in size from the 300-pound (136.2-kilogram) ostrich to the 0.08-ounce (2.27-gram) hummingbird. Some, like the Arctic tern, stay in the air for weeks at a time, while others, like the penguin, are entirely flightless.

Although traditionally a great deal of information about birds has been obtained by simple field observations, ornithology has put available technology to greater use with such techniques as banding. This technique of putting a ring or band on a bird's leg has been practiced for a long time, but now it has become a major way of obtaining information about bird movements since it is used with sensitive radar equipment. Ornithologists are also able to study bird calls in natural environment since they now have high quality, portable sound equipment.

One thing that makes ornithology different from almost every other branch of the life sciences is the fact that amateurs have regularly made major contributions to the field. Many a nonscientist who has only a passion for birds and plenty of time has been able to learn a great deal about birds and actually discovered things unknown to science. The best

known amateur may be the American artist John James Audubon (1785–1851), whose four-volume The Birds of America (1827–38) is a monument to art and science. More recently, the best work on the life history of the song sparrow was done by a housewife and mother of five, Margaret M. Nice.

Today, ornithologists are necessarily concerned with environmental conditions that affect birds since birds seem especially sensitive to pollution and climate changes. Because of this, the more ornithologists learn about birds, the more knowledge they gain about our own environment. It is significant that the environmentalist Rachel Carson chose to focus on the lack of birdsong (Silent Spring) as a tangible example of the disappearance of certain bird species due to pollution. She showed how, in many ways, birds are a sentinel species for humans, meaning that they are the first to suffer when the environment becomes degraded.

[See alsoBirds ]

or·ni·thol·o·gy / ˌôrnəˈ[unvoicedth]äləjē/ • n. the scientific study of birds.DERIVATIVES: or·ni·tho·log·i·cal / ˌôrni[unvoicedth]əˈläjikəl/ adj.or·ni·tho·log·i·cal·ly / ˌôrni[unvoicedth]əˈläjik(ə)lē/ adv.or·ni·thol·o·gist / -jist/ n.