LAMARCK, JEAN-BAPTISTE

(b. Bazentin-le-Petit, Picardie, 1 August 1744; d. Paris, 28 December 1829),

botany, invertebrate zoology and paleontology, evolution. For the original article on Lamarck see DSB, vol. 7.

Leslie Burlingame’s article on Lamarck, published in the first edition of the Dictionary of Scientific Biography, provides a lucid and reliable account of Lamarck’s life and work. The present notice is intended to supplement that article by surveying the trends in Lamarck scholarship since the original article appeared, and by updating the bibliography.

Lamarck studies since 1973 have addressed a number of tasks. These have included: analyzing Lamarck’s diverse theoretical ventures and the interrelations among them; reconstructing how Lamarck’s practice as a naturalist connected to his transformist thinking; developing a more detailed picture of Lamarck’s context with respect to the influences on his work and his influence on others; and correcting persistent misconceptions about Lamarck’s evolutionary theory.

System Building . With respect to the multiple dimensions of Lamarck’s scientific work, Lamarck’s evolutionary thinking and his work as a zoologist and paleontologist have attracted the largest share of historical attention. Nonetheless, his botany, chemistry, meteorology, and geology have also been subject to continued scrutiny. Scholars have sought to deepen the understanding of these diverse intellectual enterprises and also to illuminate the relations and differences between them. Thus in the growing literature on Lamarck’s physicochemical system (for example, Burlingame, 1981; Conry, 1981; Goux, 1997), one finds both an effort to understand that system on its own terms and an assessment of how Lamarck’s ideas about chemistry related to his later transformist biology. Each of these enterprises represent Lamarck’s intellectual predilection to system-building (“l’esprit de système”), and similar patterns of thought show up in each. As L. J. Burlingame has pointed out, the action of what Lamarck called “the matter of fire,” which was so central to Lamarck’s physicochemical system, played a key role again when Lamarck came to explain the action of subtle fluids in the formation of life.

However, the logic of Lamarck’s broad physicochemical system as set forth in 1794 did not lend itself to an analysis of life. Instead, Lamarck at this point in his career represented life as an incomprehensible principle. Furthermore, in postulating that all minerals were produced by the successive decomposition of the remains of once-living things, his system offered no way to account for life itself. The same was true for his system of geology. Though the geological system he set forth in 1802 afforded all the time necessary for small-scale changes to become large ones, for ocean basins to be displaced, and for climatic change to occur at all points of the Earth, Lamarck continued to promote the notion that all minerals were created by the decomposition of organic bodies, leaving him no way to address how life originated on the Earth in the first place (a point stressed by Corsi, 1983).

In short, the way he structured his physicochemical and geological systems offered no vantage point from which to confront the topic of life’s initial formation. When Lamarck came to the idea of spontaneous generation, he came to it from a different angle, the vantage point of his new duties as professor of the “insects, worms, and microscopic animals” at the Muséum d’Histoire Naturelle in Paris, explaining to his students the nature of life in the simplest forms endowed with it. Adopting the idea of spontaneous generation as of 1800 was a critical new step in his thinking, a precondition for the broader explanation of the successive production of life he began presenting in 1802 (Burkhardt, 1977; Corsi, 1983, 1988; Tirard, 2006).

Work as a Naturalist . Scholars have also pursued the relations between Lamarck’s broad theorizing and his practice as a naturalist. Burlingame, in her 1973 article, describes Richard Burkhardt’s argument that Lamarck’s expertise as a conchologist was intimately related to the inspiration of his belief in species change. Briefly stated, Lamarck found himself faced with the problem of explaining the differences between fossil and living shells. Unwilling to endorse the idea that fossils represented species that had all become extinct as the result of a global catastrophe, he concluded that the forms had changed over time. Having once concluded that species are mutable, he then called upon the familiar idea of the inheritance of acquired characters to explain the close relation between habits and forms that, especially in the case of birds, had been a staple of naturalists’ commentaries for decades. But it was not the case that Lamarck’s broader theory of organic change was simply an extrapolation from the idea of change at the species level: His broader theory reflected his abiding concern with animal classification, his efforts as a teacher to explain to his students the importance of studying invertebrate zoology, and his conclusion that the basic differences among the various classes of invertebrate animals could be explained as the long-term results of moving fluids acting on organic forms and structures. He invoked what he called the “power of life” or “the cause which tends to make organization increasingly complex” to account for the general, linear series that in his view best represented how the different animal classes were related to each other.

Looking at Lamarck’s later work in invertebrate zoology and paleontology has likewise proved instructive. Goulven Laurent’s (1987) comprehensive study of French paleontology from 1800 to 1860 has looked at Lamarck’s broader theorizing in conjunction with the details of his “Memoirs on the Fossils of the Paris Region” (1802–1806) and his great, seven-volume treatise, Histoire Naturelle des Animaux sans Vertèbres (Natural history of the invertebrates, 1815–1822), paying attention to the later volumes of the work instead of just the first volume, where Lamarck gave his last major presentation of his whole zoological theory. Laurent highlights the tenacity with which Lamarck pursued the task of describing and naming hundreds of previously unidentified species of fossil, and he emphasizes the importance of the way Lamarck described fossils and living forms together instead of representing them as wholly separate creations.

A similar emphasis on Lamarck’s practice as a naturalist can be found in Burkhardt’s overview of Lamarck’s work with species over the course of his entire career (1985) and his discussion of the relations between Lamarck’s work as a cabinet naturalist and the information collected by the field naturalist François Péron (Burkhardt, 1997).

The relations between Lamarck’s broad theorizing and his ongoing experience as a naturalist have also been explored by Stephen Jay Gould. Gould describes how Lamarck’s decision to make separate classes of the annelid and parasitic worms led him over time to give up his original commitment to a linear arrangement of the different animal classes and to adopt a truly branching scheme instead (2000). Gould indicates that in the very last of his publications Lamarck reversed his decades-long belief that the “power of life” was greater than the influence of environmental circumstances, admitting to the contrary that the force of circumstances was ultimately stronger than nature herself. Gould represents this as a fundamental change in Lamarck’s philosophy of nature that must have greatly distressed him.

In fact, however, Lamarck’s late writings on classification and on nature reveal no philosophical discomfort on his part. His later writings about the linear progression (or lack of it) in the animal scale do not represent this as fundamental to his philosophy of nature but instead as a pedagogical or taxonomic principle, to be followed as long as it facilitated one’s studies, but not beyond that. Thus in 1818 in Volume 5 of his Histoire Naturelle des Animaux sans Vertèbres, in discussing classifying the annelids, he states, “Who does not feel here the inconvenience of being obliged to form a simple series, when nature could not make a similar one in the order of her productions!” (p. 276). That said, Gould’s essay is a fine contribution to the ongoing study of how Lamarck’s theorizing and his practice as a naturalist interrelated. Giving up his linear arrangement of living things for a strongly branching view of life’s development, and acknowledging that the influence of the environment had had a greater role in evolution than the “cause which makes organization increasingly complex,” Lamarck showed his willingness to let the evidence of natural history be the final arbiter in determining the complex path nature had traced, over time, in bringing all the different forms of life into existence.

Influences . Another significant aspect of Lamarck scholarship over the three decades since Burlingame’s original article has been the enlarging of the cast of characters who expressed ideas of a transformist or quasi-transformist character in the late-eighteenth and early-nineteenth centuries—or whose ideas in other ways help illuminate Lamarck’s thinking. Pietro Corsi’s book The Age ofLamarck (1988) stands out in this regard. Corsi identifies in particular a “Buffonian” camp of naturalists and writers who felt shut out by the newer, more technical, positivistic orientation promoted by Georges Cuvier and who, unlike Cuvier, did not scorn the kind of broad, systematic views of nature that Lamarck sought to construct. The picture that emerges is of a complex and diversified world of professional and popular natural history where Cuvier’s power was not so dominant as earlier scholars were disposed to suggest—a point also made by Dorinda Outram (1984)—and one which also shows Lamarck’s aspirations as a naturaliste philosophe to have been less unique than Lamarck himself was inclined to suggest.

Unfortunately, Lamarck’s habit of setting forth his theorizing in a deductive fashion, without identifying his intellectual debts or otherwise specifying other writers to whom he may have been responding, continues to make it difficult to reconstruct precisely which potential influences were in fact significant for him. Be that as it may, a 2006 article by Corsi makes an excellent case that Lamarck abandoned his 1802 project of developing a new science of “biology” not because of ill health, as Lamarck maintained, but because he recognized that the new political climate would not look with favor on his materialistic explanation of all vital phenomena. Corsi argues that Lamarck revived his hopes when the Restoration seemed to promise a greater liberty of expression, but that these hopes were soon dashed, and Lamarck’s last writings reflected his efforts to avoid being accused of materialism or atheism.

Corsi (1997) has also pursued the question of Lamarck’s influence on others, including organizing a project to identify and track the intellectual careers of as many as possible of the students who registered over the years in Lamarck’s course on invertebrate zoology at the museum. Attendance in Lamarck’s classes was no guarantee of conversion to Lamarck’s ideas, but it is an index of some exposure to these ideas, and Corsi has identified a number of individual scientists and students of Lamarck, such as the Italian Giosué Sangiovanni, who can be seen as Lamarck disciples (1984). More generally, scholars have identified increasing numbers of writers who, prior to Darwin’s publication of The Origin of Species, knew of Lamarck’s ideas and were sympathetic to the notion of species transformation (e.g., Laurent, 1987; Desmond, 1989; Secord, 1991; Corsi, 2005).

Correcting Misconceptions . With respect to common misconceptions about Lamarck’s thinking, two are sufficiently prevalent to require recurrent attention. The first is that the inheritance of acquired characters was Lamarck’s primary explanation of organic change. The second is that Lamarck believed that animals could gain new organs as

the result of wishing for them. Burlingame’s DSB article of 1973 properly observes that neither caricature of Lamarck’s thinking is correct. For readers who may be coming to Lamarck for the first time, however, this observation is worth repeating. Although the idea of the inheritance of acquired characters did play a role in Lamarck’s theorizing, it was neither an idea for which he claimed credit nor the keystone of his evolutionary theory. As for the assertion that “wishing” played a role in his explanation of organic change, that is simply not true.

Beyond these misconceptions about Lamarck’s theorizing, the scholarly literature has seen another characterization of Lamarck’s views acquire more credence than the evidence warrants. This is the idea that Lamarck, in coming to believe in evolution, converted the scale of nature into what Charles Gillispie engagingly called an “escalator of being” (1959, p. 271). Peter Bowler has carried this notion further, saying Lamarck believed that “each point of the scale of being we observe today has been derived by progression from a separate act of spontaneous generation” (1984, p. 80). Although this might appear to be a logical conclusion from some of Lamarck’s statements about the effects of “the power of life,” it is not a conclusion that Lamarck ever advanced himself, nor does it correspond to his conclusion that the force of circumstances was ultimately superior to the tendency to increased complexity.

Lamarck liked to think of himself as a naturalist-philosopher. Throughout his career, there was always a tension between his ambitions as a theorist and his experience as a naturalist. For historians of science, Lamarck will continue to pose the challenge of understanding how his career and thinking were shaped by the specific scientific, institutional, cultural, and political circumstances in which he operated.

SUPPLEMENTARY BIBLIOGRAPHY

Bange, Christian, and Pietro Corsi. “Œuvres et rayonnement de Jean-Baptiste Lamarck.” Available from http://www.lamarck.cnrs.fr. Includes an elaborate chronology of Lamarck’s career and provides ready access to complete transcriptions of the greater part of Lamarck’s books and to many of his papers and other writings. It also provides a selected bibliography of historical studies of Lamarck.

Barsanti, Giulio. Dalla storia naturale alla storia della natura: Saggio su Lamarck. Milan: Feltrinelli, 1979.

———. “Lamarck and the Birth of Biology.” In Romanticism in Science: Science in Europe, 1790–1840, edited by Stefano Poggi and Maurizio Bossi. Dordrecht and Boston: Kluwer, 1994.

Bowler, Peter J. Evolution: The History of an Idea. Berkeley: University of California Press, 1984.

Burkhardt, Richard W., Jr. The Spirit of System: Lamarck and Evolutionary Biology. Cambridge, MA: Harvard University Press, 1977. Published with a new preface, 1995.

———. “Lamarck and Species.” In Histoire du concept d’espèce dans les sciences de la vie, edited by Scott Atran, et al. Paris: Fondation Singer-Polignac, 1987.

———. “Unpacking Baudin: Models of Scientific Practice in the Age of Lamarck.” In Jean-Baptiste Lamarck, edited by Goulven Laurent. Paris: Éditions du CTHS, 1997.

Burlingame, Leslie J. “Lamarck’s Chemistry: The Chemical

Revolution Rejected.” In The Analytic Spirit, edited by Harry Woolf. Ithaca, NY: Cornell University Press, 1981.

Conry, Yvette. “Une lecture newtonienne de Lamarck. Est-elle possible?” In Lamarck et son temps; Lamarck et notre temps: colloque international dans le cadre du Centre d’Études et de Recherches interdisciplinaires de Chantilly. Paris: Vrin, 1981.

Corsi, Pietro. “The Importance of French Transformist Ideas for the Second Volume of Lyell’s Principles of Geology.”The British Journal for the History of Science 11 (1978): 221–244.

———. Oltre il mito: Lamarck e le scienze naturali del suo tempo. Bologna: Il Mulino. 1983. Published as The Age of Lamarck: Evolutionary Theories in France, 1790–1830, translated by Jonathan Mandelbaum. Berkeley: University of California Press, 1988.

———. “Lamarck en Italie.” Revue d’Histoire des Sciences 37 (1984): 47–64.

———. “Les élèves de Lamarck: un projet de recherché.” In Jean-Baptiste Lamarck, edited by Goulven Laurent. Paris: Éditions du CTHS, 1997.

———. “Before Darwin: Transformist Concepts in European Natural History.” Journal of the History of Biology 38 (2005): 67–83.

———. “Biologie.” In Lamarck, philosophe de la nature, edited by Pietro Corsi, Jean Gayon, Gabriel Gohau, and Stéphane Tirard, Paris: Presses Universitaires de France, 2006.

Desmond, Adrian. The Politics of Evolution: Morphology, Medicine, and Reform in Radical London. Chicago: University of Chicago Press, 1989.

Duris, Pascal. “Lamarck et la botanique linnéenne.” In Jean-Baptiste Lamarck, edited by Goulven Laurent. Paris: Éditions du CTHS, 1997.

Gayon, Jean. “Hérédité des caractères acquis.” In Lamarck, philosophe de la nature, edited by Pietro Corsi, Jean Gayon, Gabriel Gohau, et al. Paris: Presses Universitaires de France, 2006. A penetrating analysis of the phrasing and formulation of the idea of the inheritance of acquired characters, relating to Lamarck’s own work and time and the development of the concept of heredity in the nineteenth century.

Gillispie, Charles C. “Lamarck and Darwin in the History of Science.” In Forerunners of Darwin: 1745–1859, edited Bentley Glass, Owsei Temkin, and W. L. Straus. Baltimore: Johns Hopkins University Press, 1959.

Gohau, Gabriel. “L’Hydrogéologie et l’histoire de la géologie.” In Jean-Baptiste Lamarck, edited by Goulven Laurent. Paris: Éditions du CTHS, 1997.

Gould, Stephen Jay. “A Tree Grows in Paris: Lamarck’s Division of Worms and Revision of Nature.” In The Lying Stones of Marrakech: Penultimate Reflections in Natural History. New York: Harmony Books, 2000.

Goux, Jean-Michel. “Lamarck et la chimie pneumatique à la fin du XVIII^e siècle.” In Jean-Baptiste Lamarck, edited by Goulven Laurent. Paris: Éditions du CTHS, 1997.

Jordanova, Ludmilla J. Lamarck. Oxford: Oxford University Press, 1984.

Laurent, Goulven, Paléontologie et évolution en France 1800–1860: une histoire des idées de Cuvier et Lamarck à Darwin. Paris: Editions du Comité des travaux historiques et scientifiques, 1987.

———. “Idées sur l’origine de l’homme en France de 1800 à 1871 entre Lamarck et Darwin.” Bulletins et Mémoires de la Société d’Anthropologie de Paris 1 (3–4, 1989): 105–130.

———. “Lamarck, Jean Baptiste Pierre Antoine de Monet, chevalier de (1744–1829).” In Dictionnaire du Darwinisme et de l’Évolution, edited by Patrick Tort. Paris: Presses Universitaires de France, 1996.

Laurent, Goulven, ed. Jean-Baptiste Lamarck (1744–1829). Paris: CTHS, 1997. An important collection of scholarly papers on all aspects of Lamarck’s life and work.

Outram, Dorinda. Georges Cuvier: Vocation, Science, and

Authority in Post-Revolutionary France. Manchester, U.K.: Manchester University Press, 1984.

Richards, Robert J. Darwin and the Emergence of Evolutionary Theories of Mind and Behavior. Chicago: University of Chicago Press, 1987.g

Secord, James A. “Edinburgh Lamarckians: Robert Jameson and Robert E. Grant.” Journal of the History of Biology 24 (1991): 1–18.

Tirard, Stéphane. “Génerations spontanés.” In Lamarck, philosophe de la nature, edited by Pietro Corsi, Jean Gayon, Gabriel Gohau, et al. Paris: Presses Universitaires de France, 2006.

Richard W. Burkhardt Jr.

Chevalier de Lamarck

The French naturalist Jean Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (1744-1829), is best known for his theory of organic evolution and his work on invertebrate animals.

Jean de Monet, Chevalier de Lamarck, was born Aug. 1, 1744, at Bazentin-le-Petit in Picardy. He studied for the priesthood, but on the death of his father in 1760 he joined the French army. When his military career ended because of illness in 1768, he went to Paris, where he began to study medicine. He also became interested in meteorology, chemistry, and botany.

Jardin des Plantes

Lamarck's scientific reputation was established with the publication of his Flore française (1778; French Flora), in which he combined the best of two competing systems of plant classification. This work brought him to the attention of the French naturalist the Comte de Buffon, who helped gain Lamarck's admission to the French Academy of Sciences in 1779. Buffon also secured an appointment for Lamarck as a representative of the Jardin des Plantes; in this capacity he traveled through Europe from 1780 to 1782 collecting botanical and mineralogical specimens. Then he began to write the Dictionnaire de botanique (3 vols., 1783-1789; Dictionnaire of Botany) and the Illustration des genres (1791-1800; Illustrations of the Genera) for the Encyclopédie méthodique (Methodical Encyclopedia). From 1784 to 1792 Lamarck also published many botanical articles, but the only botanical work to show the influence of Lamarck's theory of evolution was his Histoire naturelle des végétaux (1803; Natural History of Vegetables).

The Jardin des Plantes in Paris was an important scientific center for work in botany, zoology, chemistry, and mineralogy. At the time of the French Revolution, when all the institutions of the Old Regime were being examined, proposals were also made for the reorganization of the Jardin. However, in 1793, when the Academy of Sciences was suppressed for being too aristocratic, the Jardin was transformed into the Muséum National d'Histoire Naturelle (National Museum of Natural History). Because the posts in botany were filled by someone else, Lamarck was named professor of "Insects and Worms" (Carl Linnaeus's terms for invertebrates). Thus, at almost 50 years of age, Lamarck began a career in a completely new field.

Physical and Earth Sciences

Lamarck's chemical theories are usually dismissed as the product of unfortunate speculation because they represented the "old chemistry" overturned by Antoine Laurent Lavoisier and the "chemical revolution." However, they provide the key to his conception of nature and are essential features of his theory of evolution. Lamarck began his work in chemistry in the 1770s, when the four-element theory of matter (earth, air, fire, water) was still generally accepted in France. The fact that the most important element in his system was fire in its various states of modification allowed Lamarck to explain most of the known chemical and physical phenomena. His chemistry was also used to explain the mechanical interaction of individuals with the environment and, thus, evolution and the emergence of higher mental faculties.

The chemistry is presented in all of Lamarck's works dealing with evolution and in three main studies on the subject: Recherches sur les causes des principaux faits physiques (1794; Research on the Causes of the Principal Physical Facts); Réfutation de la théorie pneumatique (1796; Refutation of the Pneumatic Theory); and Mémoires de physique et d'histoire naturelle (1797; Memoirs on Physics and Natural History).

Lamarck's interest in meteorology dates from his early years in Paris. In fact, Lamarck's first known work in any field was the "Memoir on the Principal Phenomena of the Atmosphere" (1776); he later published a number of articles on the subject. Lamarck's work in this field is also generally dismissed as a collection of unfounded theories. He speculated that atmospheric change was caused by a tidal effect on the earth's atmosphere produced by the sun and the moon. He adhered to the characteristic 18th-century belief that there was a simple law which would describe and predict the weather; this course seemed possible after Benjamin Franklin's work with lightning and the progress of various sciences in the century.

The work in meteorology was also related to Lamarck's interests in biology; weather was a major environmental factor important to his theory of evolution. He believed that the importance of this field was that climate had a great influence on living organisms.

The Hydrogéologie (1802; Hydrogeology) presented Lamarck's geological views. He held that the earth was much older than the biblical account indicated. The history of the earth was one of continuous change brought about by the eroding effect of water followed by sedimentation as organic materials decayed. Great amounts of time were needed for the slow process of organic development. Evolution also required that the same factors producing geological change in the present had operated throughout the history of the earth; this view was later called uniformitarianism. These geological theories were necessary for Lamarck's theory of evolution.

Work on Invertebrates

When Lamarck accepted his appointment as professor of "Insects and Worms," a category comprising most of the animal kingdom, very little was known about invertebrates (a term introduced by Lamarck) or how to classify them. Lamarck began to study the many specimens in the Muséum, and he developed a system of classification. His work was publicized through his lectures, a number of monographs, and books, the most important of which were Système des animaux sans vertèbres (1801; System of Invertebrate Animals) and his seven-volume major work, Histoirenaturelle des animaux sans vertèbres (1815-1822; Natural History of the Invertebrate Animals). Lamarck's study of the invertebrates had important influences on the development of his theory of evolution, for the lower invertebrates, representing life in its simplest form, helped him to formulate his ideas on the nature of life.

Lamarck laid the foundations of invertebrate paleontology in his Mémoires sur les fossiles des environs de Paris (1802-1806; Memoirs on the Fossils of the Paris Area). His treatment of fossils as organic remains and his recognition of their similarities to living forms were significant for the formulation of his views on evolution.

Theory of Evolution

Lamarck's first suggestion of evolution appeared in 1800, and he went on to develop his evolutionary ideas in Recherches sur l'organisation des corps vivans (1802; Research on the Organization of Living Bodies). The Philosophie zoologique (1809; Zoological Philosophy) is his most famous full-length treatment of evolution. Some of his ideas were clarified and expanded in the "Introduction" to his Histoire naturelle des animaux sans vertèbres (1815; Natural History of Invertebrate Animals), the last presentation of his theory.

In the 18th century it was generally believed that God had created all living beings within the framework of a hierarchy or chain of being. At the bottom of the chain were the simplest forms of life; above them were the various kinds of plants, then animals, and finally man as the most complex creature of creation. Lamarck transformed this static chain of being into an evolutionary one; the complex organisms, he maintained, had evolved from simpler ones over a very long period of time.

A crucial question was the origin of the simplest form of life; Lamarck gave a materialistic definition of life and then, using his chemistry, explained that it originated spontaneously from the action of heat, light, electricity, and moisture on certain inorganic materials. He held that there were actually two forms of life produced, plant and animal, which then evolved along two separate paths. In the animal kingdom, there was not a straight line of development but, rather, a branching family tree.

To maintain that all animals, including man, had been produced in this fashion rather than having been created by God, Lamarck had to account for the origin and development of the higher mental faculties. Again his chemistry was essential; he held that the nervous fluid (a modified form of fire) was the physical cause of these phenomena at various levels in the evolution of the nervous system.

To complete his theory of evolution, Lamarck formulated four laws (1815) to explain how complex life forms arise from simpler ones: "Law 1: Life, by its own forces, continually tends to increase the volume of every body which possesses it and to enlarge the size of its parts up to a limit which it brings about itself. Law 2: The production of a new organ in an animal body results from the appearance of a new want or need, which continues to make itself felt, and from a new movement which this want gives birth to and maintains. Law 3: The development of the organs and their strength of action are constantly in proportion to the use of these organs. Law 4: All that has been acquired, impressed upon, or changed in the organization of individuals during the course of their life is preserved by generation and transmitted to the new individuals that come from those which have undergone those changes." It should be noted that Lamarck's theory of evolution is completely materialistic in the context of its time.

Lamarck died in Paris on Dec. 18, 1829, blind, impoverished, and almost ignored by his countrymen. The eulogy read by his enemy Baron Cuvier condemned all of Lamarck's "fruitless" speculations, but it did offer faint praise for his biological classifications. The Neo-Lamarckians, who adopted only part of Lamarck's theory and changed much of it to suit their needs, were important toward the end of the 19th and beginning of the 20th century.

Further Reading

Only two of Lamarck's works are available in English: Zoological Philosophy, translated by Hugh Elliot (1963), and Hydrogeology, translated by Albert Carozzi (1964). A full-length study of Lamarck in English is Alpheus Packard, Lamarck, the Founder of Evolution (1901), which is somewhat dated and has a Neo-Lamarckian bias. Lamarck's place in the development of the theory of evolution is discussed in Hiram Bentley Glass and others, eds., Forerunners of Darwin, 1745-1859 (1959), and John C. Greene, The Death of Adam (1959). Important background books are Erik Nordenskiöld, The History of Biology, translated by Leonard Eyre (1928; new ed. 1935); Arthur Lovejoy, The Great Chain of Being (1936); and Herbert Butterfield, The Origins of Modern Science (1950; rev. ed. 1957). □

LAMARCK, JEAN-BAPTISTE

LAMARCK, JEAN-BAPTISTE (1744–1829), one of the world's leading zoologists and also the first biologist to offer a full-scale theory of organic evolution.

Jean-Baptiste Lamarck was born in the small village of Bazentin in the Picardie region of France. The youngest child in a large family of the French lesser nobility, he was destined by his parents to be a priest. After his father died, he decided to pursue a military career instead. He served in the army from 1761 until an injury in 1768 forced him to resign. He subsequently made his way to Paris, where he successively worked in a bank, attended medical school, and finally concluded that what he wanted to do most was be a botanist.

Lamarck first gained visibility as a botanist by announcing to the botanists of the Jardin du Roi (the King's garden) that he could produce a guide to the plants of France superior to any guide then in existence. His project attracted the attention of the institution's director, Georges Louis Leclerc de Buffon (1707–1788), who arranged to have Lamarck's Flore française (Flora of France) published in 1778 at government expense. Buffon also championed Lamarck's election to the Academy of Sciences and gave him the official title of "correspondent" of the Jardin du Roi.

Lamarck worked productively as a botanist through the 1780s. In 1789, the year after Buffon's death, he secured from Buffon's successor at the Jardin du Roi a salaried position, that of "botanist of the king and keeper of the king's herbaria." During the French Revolution, however, royal associations became liabilities. In 1793 the Jardin du Roi was reconstituted as the National Museum of Natural History. In the reshuffling of staff at the institution, Lamarck lost his position as a botanist but received a whole new responsibility, the professorship of "worms, insects, and microscopic animals." His expertise in this area at the time was limited to what he knew as the result of being a collector of shells. Nevertheless, as he worked over the next two decades with the museum's burgeoning collections, he became the leading authority on that part of the animal kingdom he himself designated as the "invertebrates."

Lamarck was not content, however, to restrict his attention to the classification of the invertebrates. From the mid-1770s onward he nursed broad speculative notions about chemistry and meteorology, and in the 1790s he began publishing on these subjects, generally to the detriment of his reputation, since leaders in the scientific community were inclined to dismiss his formulations as examples of uncritical "system-building."

Lamarck first endorsed the idea of species mutability in 1800 in a lecture he delivered to his class on invertebrate zoology at the museum. Precisely what inspired his belief in organic mutability is uncertain, but one issue that concerned him at this time was the relation between fossil and living forms of shellfish. Confronted with the idea of species extinction, but reluctant to believe that extinction had occurred on a broad scale, he chose to think that living creatures had been gradually transformed over time in response to climatic changes on the earth's surface. He thereby took a position directly contrary to that of his colleague, Georges Cuvier (1769–1832), who opposed the idea of organic transformation while arguing that great catastrophes in the earth's past had wiped out entire assemblages of large land animals. Lamarck advanced his transformist theory at length in his 1809 Philosophie zoologique (Zoological Philosophy) and again in 1815 in his great treatise on invertebrate classification, Histoire naturelle des animaux sans vertèbres (Natural history of the invertebrates).

Lamarck's zoological theorizing encompassed much more than an explanation of how species change. He sought to account for the nature and origin of life, the production of the different forms of animal organization, and the diverse faculties to which these different forms of organization give rise. His explanation of the successive production of living forms began with the claim that the simplest forms of plant and animal life were produced by spontaneous generation. He believed these forms were then successively modified by two very different causes. The first, which he named "the power of life," was responsible for the general tendency toward increased complexity seen in the plant and animal classes alike. The second was the modifying influence of the environment, which tended to interfere with the general tendency toward increased complexity.

Lamarck's explanation of the influence of the environment on animal forms depended on the idea with which his name is now most frequently associated, "the inheritance of acquired characteristics." Changes in the environment, he claimed, led animals to develop new habits, causing them to use some organs more and other organs less. The more frequent use of an organ tended to strengthen and develop it, the less frequent use of an organ tended to weaken it and cause it to atrophy. Bodily changes thus acquired were then passed on to the next generation (provided, in the case of sexually reproducing organisms, that both parents had undergone the same changes). Habits maintained over many generations, together with the inheritance of acquired characteristics, thereby led to such diverse structural features as the long neck and forelegs of the giraffe and the rudimentary eyes of the mole.

The belief that acquired characteristics could be inherited was a commonplace in Lamarck's day. What was not accepted, however, was Lamarck's claim that such modifications could go so far as to result in new species. It was only after the 1859 publication of Origin of Species by Charles Darwin (1809–1882) that the idea of organic evolution gained widespread acceptance in the scientific community. It was only then, furthermore, that the inheritance of acquired characteristics came to be identified as a distinctively "Lamarckian" idea, in contrast to the Darwinian theory of natural selection. The reality of the inheritance of acquired characteristics was not seriously challenged until the 1880s. It continued to have adherents among biologists well into the twentieth century, but support for it waned as the experimental and other evidence advanced on its behalf was shown to be susceptible to other interpretations.

Lamarck died in 1829, blind and impoverished. In the twenty-first century his name is associated primarily with the now-discredited idea of the inheritance of acquired characteristics, but he deserves to be remembered more generally for his contributions to botanical and zoological systematics and for having been the first writer to set forth a detailed, comprehensive theory of organic evolution.

See alsoCuvier, Georges; Darwin, Charles; Evolution; Science and Technology.

bibliography

Burkhardt, Richard W., Jr. The Spirit of System: Lamarck and Evolutionary Biology. Cambridge, Mass., 1995.

Corsi, Pietro. The Age of Lamarck: Evolutionary Theories in France, 1790–1830. Translated by Jonathon Mandelbaum. Berkeley, Calif., 1988.

Lamarck, Jean Baptiste. Zoological Philosophy: An Exposition with Regard to the Natural History of Animals. Translated by Hugh Elliot. Chicago, 1984.

Richard W. Burkhardt Jr.

Lamarck, Jean-Baptiste

Botanist 1744-1829

Jean-Baptiste Lamarck was born on August 1, 1744, in Bazentin-le-Petit, France. He died on December 18, 1829. He is best known for his theory on evolution, which stated that acquired traits can be inherited. Charles Darwin later challenged this theory. Lamarck also was the first scientist to define animals as either vertebrates (having backbones) or invertebrates (those without).

Lamarck came from a long line of military horsemen. At the age of nineteen he left a school run by Jesuits (a religious order) to join the army. While serving he became interested in the plants along the Mediterranean Sea. Resigning from the army after an injury, Lamarck began to study medicine, but then switched his interest to botany . He studied under the French botanist Bernard de Jussieu at the royal botanical gardens in Paris. After years of studying and collecting, he published a three-volume work on the plants of France in 1778. This gained him recognition, and in 1781 he was put in charge of the royal gardens in Paris.

In the 1790s Lamarck changed his interest from plants to animals and soon developed a system for classifying invertebrates. He appears to have been the first scientist to relate fossils to the living creatures to which they are most similar. When the Museum National d'Histoire Naturelle was founded in 1793, Lamarck was placed in charge of the invertebrates. Lamarck was one of the founders of the modern concept of the museum collection.

From his studies on plants and animals, Lamarck developed his theory of evolution. He believed that plants and animals change their forms to adapt to their environment, and that their young inherit these changes. He thus believed, for example, that the forelegs and necks of giraffes have become longer due to the way they eat. These acquired traits would be passed on to following generations. Lamarck presented his ideas in the famous Philosphie Zoologique (1809). His theory, not unreasonable for its time, was later disproved by discoveries in genetics in the early 1900s and rejected by most scientists. However, the Soviet Union embraced Lamarck's theory in the Stalin era. This set that nation back in genetics until the 1960s.

Another area of interest for Lamarck was the weather. He was the first scientist to try to forecast it. He published an annual weather report from 1799 to 1810. He is believed to have named the various types of clouds: cirrus, stratus, cumulus, and nimbus.

see also Adaptation; Biological Evolution.

Denise Prendergast

Internet Resources

Jean-Baptiste Lamarck (1774-1829). Museum of Paleontology, University of California, Berkeley. <http://ucmp.berkeley.edu/history/lamarch.html>.