Early Scientific Studies of Dinosaurs The Europeans

Prominent scientists of the fifteenth to the eighteenth centuries connected fossils to formerly-living organisms. Among them were Leonardo da Vinci (of Mona Lisa fame; 1452-1519), Niels Stensen of Denmark (also known as Steno, Chapter 4; 1638-87), Robert Hooke (1635-1703), and Robert Plot (1640-96) of England. Plot, a museum curator at Oxford, made the first known description and illustration of a dinosaur bone in 1677. The problem with his interpretation is that although he recognized the fossil was a bone, he speculated that it might have belonged to a modern elephant and not a large, extinct, reptile-like animal. Richard Brookes made another illustration of this bone in 1763 that shows it as part of a femur from the theropod Megalosaurus from the Middle Jurassic of present-day Cornwall (Chapter 9). Neither did Brookes know the true identity of the bone, but this lack of knowledge did not stop him from naming the specimen after its superficial resemblance to a part of human male anatomy, Scrotum humanum (Fig. 3.1). One French

FIGURE 3.1 Sketch of probable dinosaur bone Megalosaurus, described by Robert Plot in 1677 in Natural History of Oxfordshire.

philosopher, Jean-Baptiste-René Robinet (1735-1820), thought the specimen actually represented an attempt by nature to imitate human organs. Fortunately, subsequent scientific knowledge falsified this hypothesis. Nevertheless, French explorers in the eighteenth century made another anatomical analogy when they yearningly named a mountain range in the northwestern part of present-day Wyoming "Les Grande Tetons."

Thus, although a dinosaur bone had been discovered, described, and illustrated by the latter part of the eighteenth century, nobody knew that it was a dinosaur bone. Unfortunately, the original specimen is lost to science. As a result, we cannot independently verify that Plot found the first identifiable dinosaur bone. In 1728, John Woodward (1665-1728) of Gresham College, London, catalogued another dinosaur limb bone that was found either in the late seventeenth or early eighteenth century, but he also did not realize the identity of its former owner. Later investigations would confirm that it was indeed from a dinosaur (probably Megalosaurus again), which makes it the first known identifiable dinosaur bone; this specimen is currently housed at the University of Cambridge. Subsequent finds of dinosaur bones in Europe, during the late eighteenth and early nineteenth centuries, resulted in people cataloguing and giving descriptions of specimens that approached a scientific methodology. However, hypotheses were rarely offered for most of the specimens and none were considered evidence of a distinctive group of long-extinct animals. In fact, such thinking was discouraged in Europe and its colonies at that time by the strong influence of religious institutions, whose advocates held that all animals on the Earth were created at the same time and none were extinct.

Ironically, a British clergyman, the Reverend William Buckland (1784-1856), published the first actual scientific description of a dinosaur. Buckland made his discovery of dinosaur remains around 1815, his find consisting of several serrated, curved teeth, together with a lower jaw containing a tooth comparable to the others (Fig. 3.2). The fossils belonged to Megalosaurus, which seems to have been a recurring find for Europeans during the late eighteenth and early nineteenth centuries. After consultations with the renowned French anatomist, Georges Cuvier (1769-1832) (whose full and rather officious name was Jean Léopold Nicolas Frédéric Baron Cuvier), and the geologist (and Reverend) William Daniel Conybeare (1787-1857), Buckland finally read his paper before a group of scientists at the Geological Society of London in 1824. Thus, Buckland is credited with naming the first dinosaur, although James Parkinson (1755-1824) almost named this animal first, in 1822. Another claim to fame for Buckland was that he was an instructor to geologist Sir Charles Lyell (1797-1875), who wrote Principles of Geology in 1830, one

FIGURE 3.2 William Buckland (top) and remains of the first named dinosaur fossil, the lower jaw of Megalosaurus (bottom). From Colbert, E. H., 1984, The Great Dinosaur Hunters and Their Discoveries, Dover Publications, N.Y., plates 3 and 4.

FIGURE 3.2 William Buckland (top) and remains of the first named dinosaur fossil, the lower jaw of Megalosaurus (bottom). From Colbert, E. H., 1984, The Great Dinosaur Hunters and Their Discoveries, Dover Publications, N.Y., plates 3 and 4.

of the most influential books in the field; he also invented the term "palaeontology" (using the British spelling). As many of the geologic principles advocated by Lyell are still in use today (Chapter 4), Buckland's influence had considerable impact on modern geology.

On a more personal note, Buckland was a strange man who reveled in his odd-ness (which supports the idea that paleontologists really have not changed very much in the past two centuries). To say that he was eccentric is akin to saying that Seismosaurus (Chapter 10) was large. He apparently delighted in proving people wrong; for example, he gained some fame when he correctly identified the purported remains of Saint Rosalia at a religious shrine in Palermo, Italy, as goat bones. He kept a menagerie in his home that included jackals, which were known to eat his free-roaming guinea pigs, and a bear named Tiglath Pileser (named after an Assyrian king, 745-727 bce). The bear was Buckland's frequent companion at academic functions and was normally clothed in a cap and gown. Buckland's interest in animals extended to consuming them, so through much experimentation he attempted to develop a system of classifying them on the basis of taste alone. Regardless of these quirks, all who knew him regarded him as brilliant and he certainly contributed much to the scientific study of dinosaurs.

FIGURE 3.3 The Mantells, Gideon Algernon (left) and Mary Ann (right), who probably were not co-discoverers of Iguanodon. From Psihoyos and Knoebber (1994), Hunting Dinosaurs, Random House, N.Y., p. 10.

FIGURE 3.3 The Mantells, Gideon Algernon (left) and Mary Ann (right), who probably were not co-discoverers of Iguanodon. From Psihoyos and Knoebber (1994), Hunting Dinosaurs, Random House, N.Y., p. 10.

A contemporary of Buckland and another important contributor to the early scientific investigations of dinosaurs was physician Gideon Algernon Mantell (1790-1852), also of England (Fig. 3.3). Only a year after Buckland's description of Megalosaurus, Mantell was the first person to name a herbivorous dinosaur and ornithopod, Iguanodon. According to a popular anecdote, Mantell's wife, Mary Ann Mantell (1796-1869); Fig. 3.3), found the teeth and bones of Iguanodon near the property of a patient while she accompanied her husband on a house call. However, Mary Ann Mantell was not seen to go with her husband on house calls, so Gideon Mantell was the only source of this story at first; later he claimed that he found the fossils himself. In her defense, she certainly was knowledgeable about fossils, as demonstrated by the 346 figures of fossils she prepared for a monograph published by her husband in 1822. In 1833, Gideon Mantell found fragments of an ankylosaur (Chapter 12), which he named Hylaeosaurus, the sauropod Peloro-saurus, and Regnosaurus, which has not been classified further because of its few remains. He was sufficiently obsessed by paleontology to fill his home with the remains of many extinct animals (as opposed to Buckland's preference for live, edible ones). This preoccupation resulted in the downfall of his medical practice, the withering of his finances, and the eventual departure of Mary Ann and their children.

Mantell's description of Iguanodon skeletal remains was followed by numerous discoveries of probable iguanodontian tracks in Cretaceous strata of southern Britain, leading to some of the first attempts to correlate dinosaur body fossils and trace fossils (Chapter 14). The Reverend Edward Tagart first presented his footprint finds in a paper to the Geological Society of London in 1846, where he attributed them to large birds. The possible reptilian origin of the tracks was proposed by 1850, but not until 1862 did Alfred Tylor, T. Rupert Jones, and Samuel Beckles publish separate reports on the hypothesis that these three-toed tracks came from similarly-sized three-toed feet of iguanodontians. This shared hypothesis was apparently derived independently and has not been disproved in the 130 years since; few other dinosaur tracemakers have been proposed for the tracks found in this region.

Anatomist Sir Richard Owen, the British analogue to Georges Cuvier of France, was a contemporary of Buckland and the Mantells. He was an expert on fossil reptiles to the point where

The study of 1inosaurs would be quite different if not y| for the etymological and paleontological contributions of anatomist Sir Richard Owen (1804-92) (Fig. 3.4).

FIGURE 3.4 Sir Richard Owen, inventor of the term "dinosaur". From Psihoyos and Knoebber, 1994, Hunting Dinosaurs, Random House, N.Y., page 11.

many people regarded him as the authority on the subject, so his word was often unquestioned (except by Mantell), regardless of the validity of his interpretations. He is best known for his invention of the term Dinosauria (whose members were called dinosaurs), which he first used in 1842 in reference to the large, extinct, reptilelike animals described by Buckland and Mantell. Dinosauria is based on the Greek roots deinos ("terrible") and sauros ("reptile" or "lizard"); in Victorian England, the common usage of the word terrible connoted the awesome nature of these animals, rather than their fearsomeness, poor hygiene, or other negative attributes. As an example of how authorities are not necessarily always correct in science (Chapter 2), Owen did not include three dinosaurs known at the time in his group, Dinosauria: Cetiosaurus, a sauropod, Poekilopleuron, a theropod, and Thecodontosaurus, a prosauropod. Instead, he classified them as unrelated reptiles.

To his credit, Owen recognized several features that are still key to the classification of dinosaurs today (Chapter 5). Also, he was a consultant to artist Benjamin Waterhouse Hawkins (1807-89), who produced the first examples of dinosaur artwork (sculptures and drawings). Unfortunately, the scarcity of dinosaur material and scientific hypotheses at the time resulted in Hawkins' artistic reconstructions of dinosaurs as ponderous and heavy-set quadrupeds, thus encouraging a popular misconception that would influence future investigators until the end of the century. In 1854, Owen was the first person to describe and name a dinosaur from South Africa, the Late Triassic prosauropod Massospondylus (Chapter 10).

France and Germany were also sites of dinosaur fossil discoveries during the nineteenth century. A Frenchman, A. de Caumont, discovered bones of Megalosaurus in Normandy in 1828, and in 1838, Jacques-Amand Eudes-Deslonchamps (1794-1867) was the first person to name a dinosaur from France, the previously-mentioned Poekilopleuron bucklandi (named in honor of Buckland). French paleontologists were also the first to record dinosaur eggshell fragments from the fossil record (Chapter 7). Jean-Jacques Pouech (1814-92), a Catholic priest, gave an excellent description of eggshells that, from their size and geologic occurrence (Late Cretaceous), could only have been from dinosaur eggs. In 1869, Phillipe Matheron (1807-99), who had followed Pouech's work, hypothesized a connection between Pouech's eggshell fragments and the Late Cretaceous skeletal material of dinosaurs found in Provence. Paul Gervais (1816-79), also of France, was the first scientist to conduct detailed analyses of dinosaur eggshell fragments, the results of which he published throughout the 1870s. In Germany, one of the best-known dinosaurs of the Late Triassic, the prosauropod Plateosaurus (Chapter 10), was discovered and named in 1837 by Christian Erich Hermann von Meyer (1801-69). After this description, other specimens of this dinosaur were found frequently in southern Germany and Switzerland, and beautifully complete examples are displayed in museums throughout Germany.

Although Charles Robert Darwin (1809-82) of England was not directly involved with dinosaur studies, he published explanations of how fossil evidence of organisms' descent with modification correlated with his observations of living animals. The timing of his publications provoked an initial discussion of the evolutionary place of dinosaurs in the history of life (Chapter 6). Darwin was a bit shy of controversy but was defended vigorously in public by Thomas Henry Huxley (1825-95). Huxley expounded with much delight on the first confirmed specimen (the "London specimen") of Archaeopteryx, a Jurassic bird with "reptilian" (dinosaurian) features that was found in 1861 (Chapters 2 and 15). Such a fossil was excellent evidence of predicted "transitional fossils" that showed links in descent between defined, major groups of organisms (Chapter 6). Huxley and Owen often disagreed on many points of evolutionary theory. Nonetheless, Huxley contributed an important insight to Owen's original classification of the Dinosauria that was far ahead of its time. In Huxley's 1868 classification, he recognized the numerous bird-like characteristics of some dinosaurs, an evolutionary linkage that enjoys nearly total support among modern vertebrate paleontologists (Chapters 9 and 15). Before he produced his classification scheme, Huxley had named a Late Triassic dinosaur from South Africa, the prosauropod Euskelosaurus (Chapter 10).

While all of these contentious events were occurring, Harry Govier Seeley (1839-1909), of England, noticed an anatomical distinction between two major groups of dinosaurs, and his 1887 report on dinosaur hip structures is still used today for their classification. One group of dinosaurs he characterized as Saurischia (reptile-hipped) and the other as Ornithischia (bird-hipped), based on the superficial resemblance of these hip structures to modern analogues in reptiles and birds, as well as a few other skeletal traits distinctive to each group (Chapter 5). On the basis of such a distinction, Seeley argued that dinosaurs did not constitute an actual group from the same ancestral stock (monophyletic), but arose from separate ancestors (polyphyletic). This interpretation touched off a spirited debate about the origin of dinosaurs that lasted for more than 100 years. Seeley, who had grown up poor and so never gained a college degree, was wise enough to work as an assistant to the Reverend Adam Sedgewick (1785-1873) at Cambridge University, who along with Charles Lyell was one of the founders of modern geological methods (Chapter 4). Cambridge was the home of the Woodwardian Museum (at that time named after John Woodward, but now named after Sedgewick), which housed the extensive collections of Late Cretaceous fossil animals that Seeley studied.

The main problem faced by paleontologists during the debates over classification was that their attempts to classify and reconstruct dinosaurs were based on fragmentary skeletal remains. For at least one species of dinosaur, Louis Antoine Marie Joseph Dollo (1857-1931) of Belgium solved the problem of insufficient evidence with his thorough descriptions of complete skeletons of Iguanodon (Chapter 11). Coal miners discovered these in 1878 in Bernissart, Belgium; subsequent excavations recovered 39 individual skeletons from the site, a phenomenal number of specimens even by today's standards. As a result, through vigorous use of scientific methods and access to many skeletons, Dollo cleared up misinterpretations about Iguanodon that had persisted since Mantell's original description, such as the placement of its thumb as a nose spike. Most importantly, at a time when all dinosaurs were regarded as quadrupeds (using four legs), Dollo firmly established the bipedal (two-legged) nature of Iguanodon. Huxley proposed the same hypothesis in

1868 for a different dinosaur species found in the USA, discussed below. Dollo, in 1887 alone, published 94 peer-reviewed papers.

Europeans worked very little on African dinosaurs during the nineteenth century, although in 1896 Frenchman Charles Deperet (1854-1929) described bones of a previously undiscovered species of sauropod, Titanosaurus (Chapter 10), and a theropod, Majungasaurus (Chapter 9), from Madagascar. These discoveries foreshadowed the potential for later major discoveries in Madagascar nearly a century later. Another French paleontologist reported dinosaur tracks from Algeria in 1880, but little other information is available about this find. Similarly, no definite reports of dinosaur fossils came out of Australia in the nineteenth century, and it was not until 1903 that William Hamilton Ferguson (1861-1957) found a theropod toe bone, nicknamed the "Paterson claw," in Cretaceous rocks of Cape Paterson, Victoria.

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