HERPETOLOGY

HERPETOLOGY. Contributions to the study of American reptiles prior to 1800 were made primarily by European travelers. Notable among the earliest contributors were the Englishman Mark Catesby and the Philadelphian William Bartram, who traveled throughout the southeastern United States making natural history observations on many organisms, including the alligator. Some American reptiles were described by Carolus Linnaeus in his Systema Naturae (1758).

In the late 1700s and early 1800s, a number of foreign naturalists and European scientists worked on American reptiles that had been sent to them, thereby adding to the knowledge of existing forms. Additions to the growing list of American reptiles were also made by John Eaton LeConte of the U.S. Army; Thomas Say, who traveled with the Stephen H. Long expedition to the Rocky Mountains (1820); and Richard Harlan, a practicing physician. Harlan attempted to draw together the body of information on American reptiles with his Genera of North American Reptiles and a Synopsis of the Species (1826–27) and American Herpetology (1827), but these contributions only partly alleviated some of the confusion regarding taxonomic matters that had developed by that time.

John Edwards Holbrook, a Charleston, S.C., physician, produced the first major contribution to U.S. knowledge of American reptiles. Holbrook's North American Herpetology (1836, 1842) was a milestone in herpetology. The success and influence of his work probably related to its completeness for the time and to the superb color lithographs drawn from living examples by talented artists. His work caught the attention of European scientists and brought a measure of recognition to the rise of science in America.

In the period immediately after the appearance of Holbrook's North American Herpetology, a number of expeditions sponsored by the U.S. government were organized to explore the American West. Notable among these were Charles Wilkes's expedition to the Pacific Northwest, Howard Stansbury's expedition to the Great Salt Lake, George M. Wheeler's explorations west of the 100th meridian, Maj. William H. Emory's Mexican boundary survey, Capt. Randolph B. Marcy's exploration of the Red River, Capt. Lorenzo Sitgreaves's expedition down the Zuni and Colorado rivers, and the Pacific Railroad surveys. Spencer Fullerton Baird brought back large collections of reptiles to museums, in particular the U.S. National Museum, which he helped establish in 1857. The reptiles collected by the U.S. exploring teams were studied by a number of scientists, including Baird. By 1880 most of the expeditions to the West had been completed and the results published, providing a first glimpse of the diversity and extent of the American reptile fauna.

Several herpetofaunal surveys were published by eastern states, including those by David Humphreys Storer for Massachusetts (1839) and James E. DeKay for New York (1842–1844). Louis Agassiz of the Museum of Comparative Zoology at Harvard added much to the knowledge of the embryology of the turtle in his Contributions to the Natural History of the United States of America (1857).

From the 1880s to the early 1900s a number of individuals made important contributions to the study of American reptiles. Samuel Garman of the Museum of Comparative Zoology compiled from scattered reports of various U.S. expeditions an important treatise on American snakes, North American Reptilia, Part I, Ophidia (1883). This work remained of considerable value to scientists until outdated by the appearance of The Crocodilians, Lizards, and Snakes of North America (1900) by Edward Drinker Cope. Leonhard Hess Stejneger of the U.S. National Museum introduced the careful designation of type specimens and type localities into the description of new species, produced an important treatise entitled The Poisonous Snakes of North America (1895), and later wrote with Thomas Barbour five editions of A Check List of North American Amphibians and Reptiles (1917). These checklists provided a concise synopsis of the known species of reptiles and amphibians and reference for other workers. In The Reptiles of Western North America (1922), John Van Denburgh of the California Academy of Sciences described new species of western reptiles and provided information on geographic distributions.

Since the 1920s, scientific investigations, centered in American universities, have been made on every conceivable aspect of the biology of reptiles. Some of the more important contributors have been Frank N. Blanchard, who was a pioneer in field studies of reptiles and developed marking techniques; and Henry Fitch, who subsequently produced some of the most complete field studies of reptiles to date. Clifford H. Pope and Archie Carr greatly expanded the knowledge of North American turtles; Carr later made pioneering contributions on sea turtles and their conservation. Alfred S. Romer contributed to the work on fossil reptiles; his Osteology of the Reptiles (1956) was still the standard reference for that field of research twenty years later. Laurence M. Klauber made many contributions on western reptiles and introduced refined statistical techniques. His book Rattlesnakes (1956) remained the most complete herpetological monograph produced by the mid-1970s. Detailed lizard population studies were published by W. Frank Blair, in The Rusty Lizard (1960).

During the 20th century several scientists produced semipopular works that served to generate wide interest in reptiles. Raymond Lee Ditmars probably did more to stimulate interest in the study of reptiles than any other individual. He routinely lectured to a wide variety of audiences and published many books, but his Reptile Book, first appearing in 1907, was one of the most stimulating to young naturalists. Karl P. Schmidt produced the Field Book of Snakes (1941) in coauthorship with D. Dwight Davis. Roger Conant wrote the first of the newest type of field guides, A Field Guide to Reptiles and Amphibians (1958), that contained range maps, color illustrations, and synoptic information about the organisms. Robert C. Stebbins further improved the field guide format with his Field Guide to Western Reptiles and Amphibians (1966). In addition to field guides, herpetofaunal surveys have been written for most of the states and have stimulated interest. Some of the better state surveys are those by Paul Anderson, The Reptiles of Missouri (1965), and Philip W. Smith, The Amphibians and Reptiles of Illinois (1961).

Few American reptiles have attracted more scientific and popular attention than the rattlesnake, a venomous snake of the pit viper family. The rattlesnake emerged as a central revolutionary icon and appeared frequently in patriotic propaganda; a flag featuring a coiled rattlesnake on a yellow background, with the caption "Don't Tread on Me," was presented to the Continental Congress by Col. Christopher Gadsden of South Carolina and unofficially adopted by Capt. Esek Hopkins as a commodore's flag. The rattlesnake holds an important place in American folklore: for example, the legendary virtue of rattlesnake oil for rheumatism; the cleverness of the roadrunner—which really does kill rattlesnakes—in corralling a sleeping rattler with cactus joints and then making him bite himself to death; or the thousands of authentic stories told around camp fires every summer. A few people die from rattlesnake bites annually, but the spread of land developments is steadily diminishing the snake population.

Three major societies sponsor periodicals to handle the great increase in the number of scholarly contributions within the field of herpetology: Copeia (1913–) is published by the American Society of Ichthyologists and Herpetologists, Herpetologica (1936–) is published by the Herpetologists' League, and the Journal of Herpetology (1968–) is published by the Society for the Study of Amphibians and Reptiles.

BIBLIOGRAPHY

Adler, Kraig, ed. Contributions to the History of Herpetology. Oxford, Ohio: S.S.A.R., 1989.

Gillespie, Angus K., and Jay Mechling, eds. American Wildlife in Symbol and Story. Knoxville: University of Tennessee Press, 1987.

Kessel, E. L. A Century of Progress in the Natural Sciences, 1853–1953. San Francisco: 1955.

J. FrankDobie

Richard D.Worthington/a. r.

See alsoMuseums ; Science Museums ; Science Education .

Herpetology

Herpetology is the scientific study of amphibians and reptiles. The term “herpetology” is derived from the Greek and refers to the study of creeping things. Birds and mammals, for the most part, have legs that lift their bodies above the surface of the ground. Amphibians (class Amphibia) and reptiles (class Reptilia), with the exception of crocodiles and lizards, generally have legs inadequate to elevate their bellies above the terrain, thus they creep.

Both Amphibia and Reptilia are within the phylum Chordata, which also includes several classes of fish, reptiles, birds, and mammals. Amphibia include the anurans, which are frogs and toads; the urodeles, which include salamanders and sirens; and the gymnophioma, which are peculiar wormlike legless caecilians. Larval amphibians (tadpoles) respire with gills whereas adults breathe with lungs. Amphibian skin is ordinarily scaleless. Reptilia include lizards, snakes, turtles, and crocodiles. They have scaly skin and respire with lungs. Extinct reptiles are of great scientific and popular interest and include dinosaurs, pterosaurs, and ichthyosaurs.

Some scientists are both herpetologists and ecologists. They study habitat, food, population movements, reproductive strategies, life expectancy, causes of death, and myriad other ecological problems. Their studies have significance not only to survival of the animals that they study but also to humans. Amphibians and reptiles manage their metabolism of xenobiotic (foreign to the body) toxic substances in much the same way as humans do, by metabolic change in the liver and other organs that permit rapid excretion. It becomes a notable concern when amphibians and/or reptiles cannot survive in an altered environment. Amphibians in a number of countries have been found in diminishing numbers and are have occasionally become anatomically abnormal. Because of their similarity in managing toxic substances, problems in these lower creatures may be of equal concern to humans.

Amphibians and reptiles are also used to study pathology and medicine in humans. Herpes viruses are microbial agents related to animal and human cancer. Burkitt’s lymphoma and Kaposi’s sarcoma are two human cancers with an established link with herpes viruses. The first cancer of any type known to be causally associated with a herpes virus was the Lucke renal adenocarcinoma in the leopard frog, Rana pipiens. Virologists working with the frog cancer can study with the herpes virus and frog cancer, experiments that would be very difficult to perform on other animals, and would be precluded for ethical reasons from human experimentation.

The feasibility of vertebrate cloning was first demonstrated in the frog, R. pipiens, in Philadelphia in 1952, and later in the South African clawed toad, Xenopus laevis, in England in 1958. Before these frog experiments, it was generally thought that cloning was a “fantastical” dream. Cloning has since been achieved with sheep, cows, and other mammals.

As economic resources, turtle meat and crocodile (raised on farms for that purpose) hides have a significant role in the Louisiana economy. Further, many amphibians and reptiles are collected for scientific study. Only rodents are used more frequently for biomedical research.

Herpetology

Herpetology is the scientific study of amphibians and reptiles . The term "herpetology" is derived from the Greek and refers to the study of creeping things. Birds and mammals , for the most part, have legs that lift their bodies above the surface of the ground. Amphibians (class Amphibia) and reptiles (class Reptilia), with the exception of crocodiles and lizards, generally have legs inadequate to elevate their bellies above the terrain, thus they creep.

Both Amphibia and Reptilia are within the phylum Chordata, which also includes several classes of fishes, reptiles, birds and mammals. Amphibia include the anurans, which are frogs and toads ; the urodeles, which include salamanders and sirens; and the gymnophioma, which are peculiar worm-like legless caecilians . Larval amphibians (tadpoles) respire with gills whereas adults breathe with lungs. Amphibian skin is ordinarily scaleless. Reptilia includes lizards, snakes , turtles , and crocodiles. They have scaly skin and respire with lungs. Extinct reptiles are of great scientific and popular interest and include dinosaurs, pterosaurs, and ichthyosaurs.

Some scientists are both herpetologists and ecologists. They study habitat , food, population movements, reproductive strategies, life expectancy, causes of death, and a myriad of other ecological problems. Their studies have significance not only to survival of the animals that they study but also to humans. Amphibians and reptiles manage their metabolism of xenobiotic (foreign to the body) toxic substances in much the same way as humans do, by metabolic change in the liver and other organs that permits rapid excretion. It becomes a notable concern when amphibians and/or reptiles cannot survive in an altered environment. Amphibians in a number of countries have been reported to be found in diminishing numbers and many are anatomically abnormal. Because of their similarity in managing toxic substances, whatever is causing the population perturbations and anomalous anatomy in the lower creatures may be of equal concern to humans.

The studies of amphibians and reptiles relating to pathology and medicine is less well known than similar studies with higher organisms. Herpes viruses are now recognized as being microbial agents related to animal and human cancer . Burkitt's lymphoma and Kaposi's sarcoma are two human cancers with an established link with herpes viruses. The first cancer of any type known to be causally associated with a herpes virus was the Lucké renal adenocarcinoma of the leopard frog, Rana pipiens. Virologists working with the frog cancer can perform a multiplicity of experiments with the herpes virus and frog cancer. The frog experiments would be very difficult to perform on other animals, and would be precluded for ethical reasons from human experimentation.

The feasibility of vertebrate cloning was first demonstrated in the frog, R. pipiens, in Philadelphia in 1952, and later in the South African clawed toad, Xenopus laevis, in England in 1958. Prior to the frog experiments, it was generally thought that cloning was a "fan tastical" dream. Cloning has since been achieved with sheep , cows, and other mammals.

As economic resources, turtle meat and crocodile (raised on farms for that purpose) hides have a significant role in the Louisiana economy. Further, many amphibians and reptiles are collected for scientific study. Only rodents exceed in number frogs used for biomedical research.

Herpetology

Herpetology is the scientific study of amphibians and reptiles. As one of the many subfields of vertebrate (animals with a backbone) biology, it focuses on the anatomy (structure), physiology (processes), behavior, genetics, and ecology of amphibians and reptiles. Although amphibians are very different from reptiles, they are grouped together in the discipline called herpetology.

Amphibians live both on land and in the water, and need to keep both their skin and their eggs moist. Frogs, toads, newts, and salamanders are amphibians. Reptiles are best suited to life on land, and both their skin and their eggs have tough outer coverings. Turtles, snakes, lizards, and crocodiles are reptiles. Both amphibians and reptiles are ectothermic (cold-blooded), meaning that their temperature matches their environment. The grouping together of these different types of vertebrate animals into one field is believed to have come from the very old tradition of lumping together all creeping or crawling organisms. In Greek, herpeton means a crawling thing and logos means reasoning or knowledge. The first book to systematically arrange animals in some sort of order was written by the English naturalist, John Ray (1628–1705), in 1693, and in that work he grouped amphibians and reptiles together.

A herpetologist, or one who practices herpetology, must be familiar with a wide variety of animals. Amphibians (whose name in Greek means "having two lives") undergo a unique process called metamorphosis. This is a dramatic but natural change in body shape that transforms an organism (like a tadpole that lives totally underwater) into an entirely different organism (like a frog that breathes air). Reptiles are often confused with amphibians from which they evolved, but they do not undergo metamorphosis and breathe air through lungs their entire lives. Amphibians must return to water to reproduce, and fertilization occurs externally (outside of their bodies). Reptiles produce a sealed egg that hatches on land, and the eggs are fertilized internally, or within the body of the female. All amphibians and reptiles belong to the phylum Chordata and the subphylum Vertebrata. Both also belong to a superclass called Tetrapoda. A superclass is a name devised by taxonomists (biologists who specialize in classifying things) when an extra classification group is needed. It is similar to the categories called superfamily and subphylum, which are also used when the realities of life do not completely fit into the standard seven-part classification scheme.

The study of herpetology has a significance beyond the animals themselves and extends to humans as well. Since amphibians and reptiles are easily kept in captivity and have systems that manage and respond to foreign and toxic substances in much the same way that human's do, they are ideal subjects for studies that benefit people. In fact, because of this similarity, many scientists believe that the health of both (especially amphibians) may serve as an early warning system for the overall health of our environment. Thus, if frogs become unexplainably sick, it may be a warning that there is something harmful in the environment, which may eventually cause health problems in humans.

[See alsoAmphibians; Reptiles ]

Herpetology

Herpetology is the study of amphibians and reptiles. The scientists who study these animals are called herpetologists. They research the structure, physiology, and behavior of these animals, as well as how they live and are related to one another. Medical researchers have been able to gain valuable knowledge from the study of these animals because they are able to survive well in captivity and they can survive operations that would kill many birds and mammals. Herpetological research also includes the extraction and biochemical study of venoms—a growing subspecialty. Because of their unique biochemistry, some venoms hold great promise as therapies for incurable or chronic diseases.

The field of herpetology appears to stem from the ancient tendency to group all creeping animals together. The Greek word herpeton means "crawling thing." Modern herpetology, as a popular and important science, tends to focus more narrowly on issues specific to orders or suborders of animals (e.g., the global decline of frog populations). Most technical research in herpetology is carried out in the field or at universities.

Herpetologists may work in zoos or for wildlife agencies, do environmental assessments, care for museum collections, or teach the public in a museum setting. Some herpetologists work as writers, photographers, or animal breeders. The majority of herpetologists work as professors or researchers in colleges and universities. While most herpetologists do have a doctorate, there have been some cases where novices were so renowned for their expertise, that they were invited to teach at the college and university level. Smaller colleges may hire teachers with a master's degree. Herpetologists with an entrepreneurial spirit may go into business for themselves, breeding and selling amphibians and reptiles, or marketing related herpetological merchandise and publications.

see also Amphibia; Reptilia.

Stephanie A. Lanoue

Bibliography

Porter, Kenneth. Herpetology. Philadelphia: W.B. Saunders Company, 1972.