THE IGUANODONS OF BERNISSARTBELGIUM, 1878 BY MELANIE VILLENEUVE RESEARCHED AND TRANSLATION FROM FRENCH TO ENGLISH OF LOUIS DOLLO’S WORK ON THE IGUANODONS OF BERNISSART IN BELGIUM REPORT PRESENTED TO THE ROYAL TYRRELL MUSEUM OF PALAEONTOLOGY JULY 2000 TABLE OF CONTENTS Acknowledgement Introduction Discovery and Geology of the site Excavation Mounting and Preparation Anatomy of Iguanodon of Bernissart A. Mantelli and Bernissartensis B. Iguanodon bernissartensis C. Iguanodon’s hand D. Louis Dollo’s hypothesis on bipedal walk of Iguanodon E. Elements observed by Dollo F. The hip structure G. Posterior limbs of Iguanodon H. Skull features of Iguanodon bernissartensis I. Mandibulae J. The vertebrae column Louis Dollo Conclusion Lexicon Bibliography Appendix A. Illustrations ACKNOWLEDGEMENT This project was put together with help of Corinne Pugh from the Tyrrell Museum’s library. The information came from Louis Dollo’s book published in 1883, translated from the French. Since most books on the Iguanodons of Bernissart are in French, I translated some of the information to provide access to English speaking people who would like to know more about the Iguanodons of Bernissart. I would like to thank Susan Sommerville, the volunteer coordinator, and Monique Keiran, author of “The Death of a Predator”, for support, help with English, note taking and reading. Darren Tanke, Tyrrell’s technician, did not realized it, but he inspired me to look closer at paleontology’s history. The story of the first bone hunters, their discovery, the time they lived in and the amazing writing, which they left for us. Sometimes, only pieces and very little clues are left, like other languages, old newspapers or bad writing and bad field notes. It takes time to figure out the puzzle, but if we do, more people will have access to documents presenting other puzzles pieces, which belong to historical paleontology. It is important to know that only sequences of Louis Dollo’s book was translated and other information came from Edward Casier and Philippe Taquet, French paleontologist. Although, the information of Louis Dollo’s book is clearly identified. Any opinion/remark or improvement that any of you can spot please let me know. In brief, thank you to the Royal Tyrrell Museum of Palaeontology for it’s resources which are more than available. Sincerely, Melanie Villeneuve INTRODUCTION The amazing discovery of the Iguanodons of Bernissart inspired the beginning of vertebrate palaeontology. Louis Dollo lived in a time where Huxley, Owen, Mantell and Cuvier were scientist to talk to or work with. Darwin had recently published the idea of evolution. At the time only a few skeletons of dinosaurs had been found. The North American dinosaurs just started to be revealed. Marsh and Cope were just starting to uncover their specimens. The classic bone war did not started yet. Although, the theory of evolution and bird-dinosaur connection were strong at the time. Louis Dollo and his famous discovery were at the dawn of vertebrate palaeontology and influenced many scientists to come and many children. Louis Dollo lived in a different world and atmosphere than the one we live in today. However, dinosaurs were probably as popular and famous as they are today. The year 2000 has brought the 1878 discovery of the Iguanodons of Bernissart to flourished in celebration after 122 years of glory for the fame of dinosaurs. Every day, scientist and palaeontologist are prospecting in the field and excavating precious fossilized bones which belong to animals that excite our mind from childhood to the making of a career. Dinosaurs died a long time ago, but they came back and took over mammals again, which we can refer as a take over of the human mind. The Iguanodons of Bernissart discovery, geology, excavation, preparation, mounting and study of their anatomy of the skeleton is presented through the following pages. In brief, palaeontology history can teach us about dinosaurs and recent palaeontology would not be the same without previous discovery. The Iguanodons of Bernissart sure changed the life of miners of Hainaut mine and the town of Bernissart. Did it change your life or wil it change your thoughts about Iguanodon? DISCOVERY AND GEOLOGY OF THE SITE In 1878, the famous discovery of the Iguanodons of Bernissart in Belgium enlighten vertebrate palaeontology. Specifically, on April 1878, a coal miner opened an accumulation of fossil bones. At first, a few bones were exposed and later became a very important site in the science of palaeontology. A series of episodes followed after the discovery brought some interventions that changed plans in future of the site. Nowadays, it is one of the world’s greatest discovery. The Royal Institute of National Science of Belgium in Brussels now displays the dinosaur specimens of the 19th century. On March 1878, Jules Creteur, a coal miner of Hainaut mine, and M. Fages alerted is chief engineer about a unique discovery. The engineer industry of coal mining named Latinis, observed the clues in the mine and signaled the discovery on April 12, 1878 to Monsieur Dupont, who was director at the Royal Museum of Natural History in Brussels. The bones and fragments were examined by P.J. Van Beneden. The coal administration council was advised of the discovery of the bones as well. The council assured to the National Scientific Patrimony the inheritance of the property of the material discovered at the site of Bernissart. The palaeontological nomenclature, through a series of forms, has names given after some members of this council. The coal compagny of Hainaut, in Bernissart, discovered the bones at depth of 322 meters. Pyrite was encountered, which is a mineral oftenly known as fool’s gold. The gallery of “Luronne” mine had crossed a clay pocket that formed by a natural shaft which collapse. It can be referred as a “cran” or notch as well. The clay pocket was also overlying beds, which hindered the collection of the coal seems. The characteristics of the discovery of the fossil site of Bernissart were in poor conditions. The poor lighting of the mine had consequences since it took time to see the presence of the fossils. They discovered it only when they dug completely through the mass of one skeleton of Iguanodontid. This particular specimen was almost all destroyed. Some miners said they encountered such pieces in 1877, a year before, but they did not know what it was and just continued there work. None of them had recognized the material until the discovery has been clearly identified in April 1878. The Royal Museum of Natural History of Belgium, (Musee Royale National d’Histoire Naturelle de Belgique), was contacted quickly by the principal engineer of Hainaut mines. The museum reacted as soon as possible to preserve the bones. From there, research on these bones was already started and lead pratical research and techniques without any problems to scientist like Louis Dollo. Although in 1878, a seismic shock from earth provoked a land fall and an inundation that interrupted the course of their work on fossils. Geologically, F.L. Cornet and A. Briart did the first important studies on formations and faults in the 1870’s. They pointed out sections curved, rounded or ellipticwhich were disposed or inclined vertically, obliquely and/or diagonal. These angles of rock would vary within the same fault from 66 to 90 degrees. The Wealdian formation included the beds that contained the Iguanodons of Bernissart. In 1923, A. Renier approved the studies of the formations from Bernissart, but could not find any other examples of such natural wells with these kinds of faults in coal. The stratigraphy of the “cran du midi” is very interesting. The clay seemed pressured and compacted which gave remarkable stratification to the site. Although, clay pockets were frequent, the site also have coal, schistes (rock found in Europe like England) and sandstone. The remains of the Iguanodons of Bernissart and other fossilized organisms were found at the depth of 322 meters. Nevertheless, the formation was reached by a gallery within the mine at the depth of 260 meters. The Iguanodons were in clay benched really neatly stratigraphied. However, there was here and there some inclinations that could go upright. Observations of new coal gallery down below let to conclusion that the pit would extend down 356 meters under soil’s surface. This last level correspond to a dept of 206 meters from the surface of the coal layer. F.L. Cornet studies lead him to think that under the level was 322 meters to 172 meters under the surface of coal land. According to E. Dupont (1897), the remains of the Iguanodons were found in 4 levels of fossil layers within a total repartition of land from 34 meters and depth of 322 meters to 356 meters. In 1918, studies revealed the formation has an opening of coal in deeper ground. The origin of such land accidents or formation’s work through out time sure allowed many scientists to interpret diverse opinions and lead important research. Earlier, before the great discovery in 1875, Omalius D’Halloy, the father of Belgium geology, thought the site was the result of volcanic cheminees. Many scientist studied the site of Bernissart and it’s geology for many years to come. E. Dupont thought that Wealdian time or Iguanodons of Bernissart lived in a valley at the time (Lower Cretaceous). The Bernissart fauna and flora age is estimated between 120 to 140 million years ago. The site has long thought to be Jurassic like Dollo suspected, but it is indeed Lower Cretaceous after studies of the 20th century. The Wealdian formation revealed the coal was deposited before a marine erosion from transgression courses during Late Cretaceous. Therefore, the Wealdian Formation is Lower Cretaceous. The appendix contains geological illustrations and maps of the site. EXCAVATION In 1978, the site unveiled great bones and excavation started and went on till 1902. They spent twenty four years mining for dinosaurs. Some difficulties were encountered while excavating. The bones dimension was quite large and therefore caused some problems weather the weight of it, the space consuming or simply getting out of the mine. The bones were also delicate to handle because of the material they fossilized into. The excavation of the site was hard sluggish labour. Preparation, mounting and study of the bones took a quarter of a century. The excavation itself took 24 years of painstaking labour work. The bones were removed in blocks. The blocks contain the bones and the matrix clay. Plaster of Paris and metallic circles (like chicken wire) were used to reinforcement for transportation of the bones. Some of the blocks weighted more than at ton. All of the blocks together weighted more than a 100 tones. The position of bones were all mapped. The position of the blocks were mapped as well, which allowed information for study and reconstruction of the site locality, the bones and for primitive relations. A decameter and boards were used for measurements and mapping. Extreme precautions were undertaken for the bones. The bones were submerged in carpenter’s hand glue. The recontruction of the skeletons with missing gaps were filled with “carton-pierre” and plaster of Paris. All efforts in reconstruction of the Iguanodons bernissartensis were a success. The skeletons are now exposed in the vertebrate room of the Royal Institute of Belgium. The work was very well done for the 1880’s and very well documented. MOUNTING AND PREPARATION The mounting represents a big amount of work and energy which admiration will take place. At first try, in 1880 was great and in 1883 it was a perfect mount, from studies done by Louis Dollo. One individual was reconstructed and eight followed closely. Drawings of Iguanodons skeletons were done in 1882 by G. Lavalette which served for study and reconstruction. In 1883, a glassy window has been installed for safety and for the conservation and preservation of the skeletons mount of specimen of Iguanodons bernissartensis. Observations by Louis Dollo pointed out strange aspects of the skeleton such as wringed neck (twisted) and legs stretched out. Conservation of such bones with pyrite filling every gap was not easy. Instability and/or disintegration came from what is known as the pyrite disease; the “mal de pyrite”. Pyrite disease is an alteration of pyrite, Iron sulfide or “sulfide de fer”, in instability form, from air action a decomposition with oxygen and liberation of sulfates of Iron yellow and white. The pyrite will slowly deteriorate and the same for the Iguanodons of Bernissart. The Iron sulfide (FeS) or pyrite could oxidized the bones to dust. They are incubated in a glassy, mentioned above, box to prevent any water or moisture to deteriorate these Iguanodons preserved in some pyrite. The process of deterioration was reduced by applying a mixture of alcohol and rubber lacquer on them. Palaeontologist did preserved them till today, but will future events keep the Iguanodons safely? From the discovery of the site to excavation to mounting, to preparation and study of the anatomy of the Iguanodons. Louis Dollo became famous and gave Iguanodon bernissartensis it’s right place in vertebrate palaeontology. ANATOMY OF IGUANODONS OF BERNISSART The principal characteristics observed and attributed to Iguanodon bernissartensis are found through the study of the anatomical structure is usually the material we deal with but sometimes footprints, coprolites, or skin impression can give us clues about their anatomical features. Firstly, the Iguanodon belong to the order of the Ornithischian or Avipelvians which mean they have a bird hip. Although, they were reptile creatures, called dinosaurians, with diapsids temples. (The skull has two cavities or orbit for the temples, which are located after the eye orbit, we call them diapsids foe some animals.) They were bipedal and might have been occasionally quatrupedal. The teeth revealed that they were herbivores. The premaxillary was pronounced and was added to the predentary below. A. MANTELLI AND BERNISSARTENSIS However, two species of Iguanodon were identified from Bernissart site. One individual complete skeleton of Iguanodon mantelli van meyer and many species of Iguanodon bernissartensis boulenger were within the mine of Hainaut. Somehow a lot of incomplete pieces of bones of Iguanodon were isolated. It is first of all, by the size that both species are differentiated. Iguanodon bernissartensis was bigger than Iguanodon mantelli. Iguanodon bernissartensis could reached ten meters from head to tail. For Iguanodon bernissartensis, six sacral vertebrae are running along the sacrum, but for Iguanodon mantelli only five sacral vertebrae are found. Iguanodon bernissartensis would measure 9m50cm almost 10 meters and about 5 meters in height. Iguanodon mantelli measured 6 meters long and 4 meters in height.
Note: Iguanodon mantelli is known from 2 skeletons (1978) and some partial pieces. Iguanodon bernissartensis is known from 21 complete skeletons and many partial Pieces. Iguanodons bernissartensis and Iguanodon mantelli are recognized as 2 different genus of Iguanodontids. They can be seen to modern day like white-tail deer and red-tail deer. Some scientist are arguing about the possibility of a sexual diphormism or a age difference like juvenile and adults. The distinct characteristics and the intense study support and recognized both Iguanodons bernissartensis and Iguanodon mantelli as different animals. IGUANODON BERNISSARTENSIS The number of vertebrae of the neck, dorsal and of the sacrum is 34. The number of vertebrae for the tail is of 51 for the first mounted skeleton of Iguanodon bernissartensis. In overall, the vertebrae column had over 80 vertebrae. The femurs have been studied as well and the muscles attachment from femur to tail. Observations of femurs and the 4th trochanter, located on the 1/3 of the femur’s length, took us to the duck’s posterior which is similar. The 4th trochanter served has an attachment of a caudo-femural muscle originated from the tail to allow movement of the tail. Ducks have the same feature which they use for walking on land. (Dollo, 1883). The arms are relatively short and the humerus is characterized by a sharp curved sigmoidale, like all ornithopods have. The arm lead to a hand with five fingers, which the first finger has four phalange. The fifth finger, thumb, is transformed as a claw or eperon. The important development of the prepubis apophysis is more than oftenly a need for more resistance of abdominal muscles used for diving in the water. Iguanodon bernissartensis had that feature as well. The tail of Iguanodontids had many caudals and development of hemales apophysis (hermapophyses) and neurals (neuropophyses) that contributed to impose the powerful femural-coccygio muscle which attach to the 4th trochanter of the femura. The tail was probably used for balance, swimming and defense.
B. IGUANODONTID HAND Finger Five V -thumb has a claw for defense Finger One I -Index -3 phalanges, followed by the arm alignment Finger Two II -middle -3 phalanges, followed by the arm alignment Finger Three III -ring -3 phalanges, followed by the arm alignment Finger Four IV -pinky -longest finger of the hand of Iguanodontids -4 phalanges -no ungual –no nail, but bone nodule instead is present -angled laterally positioned or opposite characteristics. -animal of today used an angled laterally finger for prehensibility. “A real hand” observed Louis Dollo. Iguanodon could used is IV finger or pinky to pick up objects. He could allow is pinky to curve back in the palm of his hand. The same thing human does with their thumb. Louis Dollo’s l'osteologie des mosasauridae, 1882-83 translation from the French.In 1882, fifteen specimens were under process of preparation, out of 22 that were extracted at the time. 1881, G.A. Boulenger of the Royal Academy of Belgium, which the last name of Iguanodons bernissartensis boulenger come from. The skull has double length compare to it’s wideness, which measure approximately 65 centimeters. Nasals projected on one third of it’s lower jaw. The orbital vertical has a large diameter temple orbit opened widely. The « omoplate » or scapula minimum size is almost 6 times it’s maximum length. The coracoid is equipped of a low or scoop neckline related to the exterior. Six sacral vertebrae are found. -Boulenger’s description od I. Bernissartensis quoted by Dollo. LOUIS DOLLO’S HYPOTHESIS ON BIPEDAL WALK OF IGUANODON Our (Dollo speaking) studies id done, and will allow us from now on, to admit along with Owen the aquatic life. The arguments on which we will rely on for demonstrating the exactitude and our ways to see and group two principal or main studies; bipedal walk or progression of life in the water. -M.L. Dollo, 1882 ELEMENTS OBSERVED BY DOLLO (1882) 1-The alignment and work from hip to it’s posterior or back limbs compare to birds, especially the “Ratitoe” and Iguanodons. 2-The difference in structure between it’s front limbs and back limbs. 3-The volume of it’s head and thorax compare to it’s regions for quadrupedal Reptiles. 4-The nature of the vertebrate column. 5-The footprints (Ignites) found in Wealdian Formation describe by M. M. Beckles, Tylor, Struckmann and Grabbe. THE HIP STRUCTURE The hip-“The Ilia are prolonged forwards, in front of the accetabulum, as well behind it; and the resemblance to the bird’s ilium is greatly increased by the widely arched form of the accetabular margin of the bone, and the extensive perforation of the floor of the accetabulum.” (T.H. Huxley, On the animals, etc., p.284 resource used by Dollo) Dollo- We are about to confirmed completely the assertion of the English scientist about the ilium features. (listed below) 1-Iguanodons, like the birds, the articulation iliobian is done at the extremity of the special apophysis of the ilium. Although, the articulation of the ilio-ischiadic is sessile compare to the first of these bones. 2-The edge of the accetabulum of the ilium is bulging to the back, pointing towards the exterior and lead to a protuberance which Dollo calls an anti-trochanter also developed for the African Orstrich (Struthio camelus). Iguanodon hip and birds April 1883, DolloThe only serious difference, we know of, which exist between the ilium of Dinosaurians and birds is the presentation of the two bones reunited directly, for birds and/or attachment related to the vertebrae column, on the median line. The Iguanodon’s ilium is separated or is diverged and this even for primitive Iguanodons. a-The iliums are separated in infant birds. b-Dinosaurians and birds can not be completely related since these dinosaurs would no longer be dinosaurs but birds. Although, a characteristic of inferiority had a compensation the Iguanodons had a long tail and front limbs, which birds do not have. c-The hesperonis, the most ancient bird we know of, already has the iliums reunited on the median line I their region post-accetabulum. However, they are still free or slightly separated in their anterior part. The opposite is happening for the “Ratitoe” iliums. d-Other dinosaurians, such as, the Stegosaurus ungulatus, (discovered by Marsh, USA, 1881) the iliums are reunited on the median line and the same for the Omosaurus armatus described by Owen. In brief, the ilium of the dinosaurians, like the Iguanodon, is concording in the most remarkable way with the homologous part that birds have. The hip of Iguanodon has articulations in pairs to the number three. I -Ilio-ischiadic II -Ischio-post-pubian III -Pubo-iliac The hip of juvenile chicken has also 3 articulations observed. I -Ilio-ischiadic II -Ischio-post—pubian III -and an articulation not determined by nature yet. This explanation seems hard to work with but the position, direction and the shape of birds and proportions taking in account can be compared and questioned about dinosaurians. It is an hypothesis that demands development of research (wrote Dollo in 1883). Also, the 3rd articulation of the pair of pelvian arch in birds could not be pubo-illiac, which will require further studies and better significance as Dollo thought in 1883. POSTERIOR LIMBS OF IGUANODONS The femura of the Iguanodon bernissartensis resemble the one birds have. a-The ectocondyle of the femura in dinosaurians has no post-axial crest between the tibia and the fibula. b-The bird femura is always shorter than the tibia, which is inversed in Dinosaurians (dinosaurs known to the time of Dollo). c-Concerning the existence of the ectocondylan crest; Dollo beilieved it did not only exist, but was well-develop for Iguanodon bernissartensis. Dollo and T.H. Huxley believed in further evidence of the bird-dinosaur connection in April 1883. In addition, the development of 4th trochanter indicated frequent lateral movements of the appendical caudal, which lead Owen and Dollo to believe in the advantage of fast swimming aptitudes in Iguanodon bernissartensis. SKULL FEATURES OF IGUANODON BERNISSARTENSIS Described by M.L. Dollo, August 1883. His studies involved seven skulls specimens, which gave him difficulties on the listed below. 1-specimens mutilation 2-obliteration of sutures per age 3-filled cavities by lots of pyrite harder than bone, which was most impossible for Dollo to remove. Dollo explained that in same cases his observations are less complete. A. Mandibulae Owen demonstrated the affinities lacertilians instead of crocodilians in 1855. Remarks from reptiles skull: 1-The weakest dimension is the height of the skull since
it was compressed vertically. Mandibulae features for Iguanodon: 1-The
weakest dimension of the skull is the bilateral diameter and compressed
transversally or bare crossed. Iguanodontidae teeth had compressed shape frontward to back and fine teeth with an edge. Dimensions of the skull of Iguanodon Length 0,65 meters Height 0,35 meters (including mandibulae) Wideness 0,25 meters THE VERTEBRAE COLUMN The whole vertebrae column holds 85 vertebras. Cervical 10 Dorsal 18 Sacral 6 Caudals 51 Total 85 vertebras M.L. Dollo, August 1883. Dollo observed 26 pairs of ribs on Iguanodon bernissartensis Ribs cervical 9 Ribs dorsal 17 Total ribs 26 Coistoids of the tail of Iguanodon bernissartensis Dollo observed 13 Coistoids front Ie to XIIIe caudal. Chevrons-missing on the two first caudals. All caudals have chevrons till the 37e caudal, then they disappeared. LOUIS DOLLO Louis Dollo studied at the Academy in France. The same Academy than Beneden. Dollo, was hired to study the new Iguanodons of Bernissart in April 1878. He published his first notes in 1882. “The detailed study of all this material was undertaken by the master hand of Louis Dollo, a Belgian of French origin and mining engineer who was named conservator of the Royal Museum in 1882. Among other remarkable studies, Dollo showed that herd of Iguanodon from Bernissart comprised one individual of Iguanodon mantelli and 30 individual of Iguanodon bernissartensis.” -Philippe Taquet, Ph.D. 1998. Louis Dollo was born in 1857 in France. He was 21 years old when he started to work for the Belgium Museum as an “Aide-Naturalist” and worked intensely on the Iguanodon from 1878. He published many papers and notes. He died at the age of 74 in 1931. His work remains an historic moment in the world of palaeontology, even today. CONCLUSION “The Iguanodon’s complaint” written by Marcel Lefebvre in 1912. (Taquet, 1998). Have pity on an Iguanodon Have pity on an Iguanodon Have pity on an Iguanodon Note: Bernissart is a small town in the Walloon region of Belgium; the small province of Borinage is also found there, from which “Borain” humus would come. The French-speaking Walloons have long rivalry with Dutch-influenced Flemish region of Belgium; hence the pointed barbs. Note from Philippe Taquet, Ph.D. 1998. LEXICON TRANSLATION FROM THE FRENCH TO ENGLISH Geologie = Geology coal = charbon perone = fibula Minieres = mining os = bone carte = map Argile = clay fosse = pit fossiles = fossils Formation = formation crane = skull sable = sand Carriere = quarry Cretace = Cretaceous restes = fragments/pieces Depot = deposits machoire = jaw couche = layer Niveau = level dent = teeth superieur = upper Inferieur = lower vertebres = vertebrae terrain = land Sacrum = sacrum Weldien = Wealdian Corne = horn Caillou = pebbles marecage = marsh empreinte = footprint/Ignite Sediments = sediments conglomerats = conglomerates Gravier = gravel sternum = sternum especes = species Gisement = formation fond = bottom etat = condition Bec = bill disparu = disappear puits = well Roches = rocks gres = sandstone houille = coal Bruxelles = Brussels Belgique = Belgium discovery = decouverte Squelette = skeleton breche = opening weight = poid Skin = peau grandeur = size height = grandeur/hauteur Eperon/griffe = claw bras = arms jambes/pattes = legs Millieu = middle bassin = hip BIBLIOGRAPHY 1. Casier, E. Les Iguanodons de Bernissart. 1978. Editions du Patrimoine de l’Institut Royale des Sciences Naturelles de Belgique. Brussels, Belgium. Pp. 166 2. Dollo, M.L. Note sur l’Osteologie des Mosasauridae. 1883. Musee Royale d’Histoire Naturelle de Belgique. Belgium. Estimated pp. 330 3. Taquet, P. Dinosaur Impressions, Postcards from a palaeontologist. 1998. Cambridge University Press. New York. Pp. 244 |
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