Before Jurassic Park: The study of ancient DNA.

A tick entangled in a dinosaur feather (From Peñalver et al., 2017)

We all know the story. In the early 80’s, John Hammond, a shady entrepreneur, created the ultimate thematic park by cloning dinosaurs from preserved DNA in mosquitoes entombed in amber. The idea, as Michael Crichton acknowledged, was not new.

In 1982, entomologist George Poinar and electron microscopist Roberta Hess at University of California,  found exceptional evidence for the organic preservation of a 40-million-year-old fly in Baltic amber. They saw intact cell organelles, such as nuclei, and mitochondria, and wondered whether these results were replicable. After a letter from Poinar to a colleague, they received, a week later,  a 70–80 million-year-old wasp in Canadian amber. The wasp also revealed evidence of cellular structure. The realization that amber was a special source of cellular preservation caused them to wonder if it could be a source of molecular preservation, too.

Quagga mare at London Zoo, 1870, the only specimen photographed alive

Poinar and Hess joined forces with Allan Wilson, Professor of Biochemistry at Berkeley, and Russell Higuchi, a molecular biologist and postdoctoral researcher in Wilson’s lab. A year later, they embarked on the first experiment to test ideas about the preservation and extraction of DNA from insects in ancient amber. Poinar selected eight specimens that would potentially offer optimal preservation of DNA. In two of the eight insects were signs of DNA, but no hybridization experiments were done to determine whether the results were due to human contamination.

Soon, Wilson and Higuchi turned their attention to the quagga, a subspecies of plains zebra that went extinct in 1883. The study, lead by Russell Higuchi, used two short mitochondrial DNA sequences from the muscle and connective tissue from a 140 year-old quagga from the Natural History Museum in Mainz, Germany, and confirmed that the quagga was more closely related to zebras than to horses.
The survival of DNA in quagga tissue and in an Egyptian mummy created waves among the scientific community, and in the autumn of 1984, Wilson and his lab submitted to the National Science Foundation (NSF), the first official research proposal to search for DNA in ancient and extinct organisms. They wrote: “This is the first proposal to study the possible utility of DNA to paleontology. If clonable DNA is present in many fossil bones and teeth and in insects included in amber, a new field, molecular paleontology, can arise.”

 

Reference:

Jones, E.D., Ancient DNA: a history of the science before Jurassic Park; Studies in History and Philosophy of Biol & Biomed Sci (2018), https://doi.org/10.1016/j.shpsc.2018.02.001

Poinar, G. O., & Hess, R. (1982). Ultrastructure of 40-million-year-old insect tissue.
Science, 215(4537), 1241–1242. DOI: 10.1126/science.215.4537.1241

Higuchi R, Bowman B, Freiberger M, Ryder OA, Wilson AC. DNA sequences from the quagga, an extinct member of the horse family. Nature. 1984;312:282–284. doi: 10.1038/312282a0.

Peñalver, E. et al; Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages, Nature Communications volume 9, Article number: 472 (2017)
doi:10.1038/s41467-018-02913-w

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Forgotten women of Paleontology: Elizabeth Anderson Gray

Elizabeth Anderson Gray (1831 – 1924) Image: The Trustees of the Natural History Museum, London

The nineteen century was the “golden age” of Geology. The Industrial Revolution ushered a period of canal digging and major quarrying operations. These activities exposed sedimentary strata and fossils, and the study of the Earth became central to the economic and cultural life of  Great Britain. The most popular aspect of geology was  the collecting of fossils and minerals and the nineteenth-century geology, often perceived as the sport of gentlemen,was in fact, “reliant on all classes”. Women were free to take part in collecting fossils and mineral specimens, and they were allowed to attend lectures but they were barred from membership in scientific societies. It was common for male scientists to have women assistants, but most of them went unacknowledged and become lost to history.  However, some women found the way to avoid that fate. One of those women was Elizabeth Anderson Gray.

Born in Alloway, Ayrshire, on February 21, 1831, Elizabeth Anderson Gray  is considered as one of the foremost Scottish fossil collectors of the late 19th and early 20th centuries. She had little formal schooling but as a girl joined her father, Thomas Anderson, in his hobby of fossil collecting. In 1856, she married a Glasgow banker, Robert Gray, co-founder of The Natural History Society of Glasgow. She took a geology course for women at Glasgow University and she trained her children to document their findings too. She was also friend of Jane Longstaff, a British malacologist and expert in fossil gastropods of the Palaeozoic. The Gray collections, considered important in studies of Ordovician fauna, were sold to institutions. In 1920 a major part of the collection was acquired by the British Museum for £2250. Charles Lapworth, in his work on the ‘Girvan Succession’ referred extensively to E. Gray’s collection in his stratigraphical correlations.

In 1900, Elizabeth Gray was made an honorary member of the Geological Society of Glasgow for her many contributions, and in 1903, she was awarded the Murchison geological fund in recognition of her skilful services to geological science. She continued gathering fossils until her death on 1924.

 

References:

BUREK, C. V. & HIGGS, B. (eds) The Role of Women in the History of Geology. Geological Society, London, Special Publications, 281, 1–8. DOI: 10.1144/SP281.1.

M. R. S. Creese (2007), Fossil hunters, a cave explorer and a rock analyst: notes on some early women contributors to geology, Geological Society, London, Special Publications, 281, 39-49. https://doi.org/10.1144/SP281.3

 

Forgotten women of Paleontology: Carlotta Joaquina Maury

Carlotta Joaquina Maury (January 6, 1874 – January 3, 1938)

In the 18th and 19th centuries women’s access to science was limited. Early female scientists were often born into influential families, like Grace Milne, the eldest child of Louis Falconer and sister of the eminent botanist and palaeontologist, Hugh Falconer. Unfortunately, their contribution has not been widely recognised by the public or academic researchers. Women collected fossils and mineral specimens, and were allowed to attend scientific lectures, but they were barred from membership in scientific societies. By the 1880, in the United States, geology was a marginal subject in the curricula of the early women’s colleges until an intense programme was started at Bryn Mawr College, a decade later.

Carlotta Joaquina Maury was born on January 6, 1874 in Hastings-on-Hudson, New York. She was the youngest  sister of astronomer Antonia Maury, who worked at the Harvard College Observatory as one of the so-called Harvard Computers. She was also the granddaughter of John William Draper and a niece of Henry Draper, both pioneering astronomers. Maury maternal grandmother was Antonia Coetana de Paiva Pereira, member of Portuguese nobility serving at the court of Emperor Dom Pedro I of Brazil, a connection which had and important influence on her career.

Harvard Computers at work, including Henrietta Swan Leavitt (1868–1921), Annie Jump Cannon (1863–1941), Williamina Fleming (1857–1911), and Antonia Maury (1866–1952).

She was educated at Radcliffe College from 1891 to 1894. Influenced by Elizabeth Agassiz, co-founder and first president of Radcliffe College, Maury attended Cornell University, where she obtained a PhD in 1902, making her one of the first women to receive her PhD in paleontology. Her mentor was Gilbert Harris, who founded the scientific journal Bulletins of American Paleontology.

Before completing her PhD, she spent a year at the Sorbonne. After teaching in several universities, she investigated microfossils in drilling samples along the Texas and Louisiana coasts and was given an official title as a paleontologist for the Louisiana Geological Survey. In 1910, Maury was recruited to be the paleontologist for oil geologist A.C. Veatch’s year-long geological expedition to Venezuela, a study funded by the General Asphalt Company of Philadelphia. Her discovery in Trinidad of Old Eocene beds with fossils faunas related to those of Alabama and the Pernambuco region of Brazil was the first finding of Old Eocene in the entire Caribbean and northern South America region.

Carlotta Maury at the Palaeontology Laboratory in Cornell. (From Arnold, 2009)

After a short break for teaching at Huguenot College in Wellington, South Africa, Maury returned to the Caribbean in 1916 as the leader of the “Maury Expedition” to the Dominican Republic, during a period of violent political upheaval on the island. The results  – type sections and descriptions of fossils, including more than 400 new species – are the foundation for the international Dominican Republic Project, a multi-disciplinary research effort that aims s to understand evolutionary change in the Caribbean from the Miocene era to the present day.

Her reputation for being extremely efficient and energetic helped her to defy the prejudice against professional women at the time. She was a consulting palaeontologist and stratigrapher to Royal Dutch Shell’s Venezuela Division for more than 20 year, and one of the official palaeontologists with the Geological and Mineralogical Service of Brazil. In 1925, she published “Fosseis Terciarios do Brazil with Descripção de Nova Cretaceas Forms” where she described numerous species of mollusks from the northeastern coast, performing the stratigraphic correlation of these faunas with similar faunas of the Caribbean and Gulf of Mexico.

C. Maury in 1916, Dominican Republic.

Maury was fellow of the Geological Society of America, and of the American Geographical Society. During the last decade of her life, she dedicated to publishing her consulting reports. Her last report about the Pliocene fossils of Acre, Brazil, appeared in 1937, shortly before her death. The same year she was elected member of the Brazilian Academy of Sciences.
Carlotta Maury died January 3, 1938 in Yonkers, New York.

References:

Lois Arnold (2009), The Education and Career of Carlotta J. Maury: Part 1., Earth Sciences History 28.2 (2009): 219-244 https://doi.org/10.17704/eshi.28.2.343vu112512w8170 

M. R. S. Creese (2007), Fossil hunters, a cave explorer and a rock analyst: notes on some early women contributors to geology, Geological Society, London, Special Publications, 281, 39-49. https://doi.org/10.1144/SP281.3

Burek, C.V. and B. Higgs, eds. (2007) The Role of Women in the History of Geology (London: Geological Society).

 

A brief history of Mesozoic theropods research in Gondwana

Snout of the ceratosaurian Genyodectes serus

In the last decades, the study of Gondwanan non-avian theropods has been highly prolific, showing that the group reached a great taxonomic and morphological diversity comparable to that of Laurasia. The Mesozoic Gondwanan neotheropod record includes: coelophysoids, basal averostrans, ceratosaurids, abelisauroids, megalosauroids, carcharodontosaurids, megaraptorans, basal coelurosaurs, compsognathids, alvarezsauroids, unenlagiids, and basal avialans, as well as putative tyrannosauroids, ornithomimosaur-like forms, and troodontid. Therefore, the Gondwanan fossil record has been crucial to understand the evolution and global biogeography of dinosaurs during the Mesozoic.

The first probable theropod remains from Gondwana were discovered in Colombia by Carl Degenhard, a German engineer, in 1839. At that time the word “dinosaur” did not even exist yet. Although Degenhard identified them as bird footprints, his brief description suggests that they were tracks of bipedal dinosaurs. But it was not until 1896 that the first Gondwanan theropod was named by the French palaeontologist Charles Depéret as “Megalosaurus” crenatissimus from the Upper Cretaceous of Madagascar. Several theropod remains were described from India, Africa, and South America during the 19th century. These early fragmentary discoveries lead the authors of the late XIX and early XX centuries to interpret them as belonging the same lineages present in Europe and North America.

Elaphrosaurus bambergi (Museum für Naturkunde 4960, holotype) from the Upper Jurassic of Tanzania (Janensch, 1920)

In 1901, A. Smith Woodward described Genyodectes, based on fragmentary skull bones, including portions of both maxillas, premaxillae,  parts of the supradentaries, and some teeth, discovered by Santiago Roth in Chubut, at the end of the 1880s. Genyodectes remained as the most completely known  theropod from South American until the 1970s. In 2004, O. Rauhut concluded that Genyodectes is more closely related to Ceratosaurus than the more derived abelisaurs.

Between 1915 and 1933, the most relevant Gondwanan theropod discoveries were produced by the work of the German palaeontologists Frederich von Huene, Ernst Stromer, and Werner Janensch, including for the first time the publication of very informative partial skeletons, such as those of Spinosaurus aegyptiacus and Elaphrosaurus bambergi (Stromer, 1915; Janensch, 1920). Despite its low fossil record, Spinosaurus is one of the most famous dinosaur of all time. This gigantic theropod possessed highly derived cranial and vertebral features sufficiently distinct for it to be designated as the nominal genus of the clade Spinosauridae. But during and after the Second World War the influence of the German palaeontology in the research of Gondwanan theropods abruptly declined.

Skull and neck of Carnotaurus sastrei

By the 1960s, the Argentine biologist Osvaldo Reig, together with Rodolfo Casamiquela and José Bonaparte, began to explore the Mesozoic rocks of Argentina looking for fossil tetrapods. In 1985, Bonaparte published a note presenting Carnotaurus sastrei as a new genus and species and briefly describing the skull and lower jaw. It was collected in the lower section of La Colonia Formation, Chubut Province. The discoveries of Bonaparte and his collaborators resulted in the recognition of the Patagonian theropod record as the most relevant and informative among Gondwanan continents. Some of the theropod species discovered in Patagonia are known on the basis of skulls and fairly complete skeletons offering insights into the anatomy and phylogeny of abelisaurids, carcharodontosaurids, and maniraptorans.

References:

Martín D. Ezcurra, and Federico L. Agnolín (2017). Gondwanan perspectives: Theropod dinosaurs from western Gondwana. A brief historical overview on the research of Mesozoic theropods in Gondwana. Ameghiniana 54: 483–487. Published By: Asociación Paleontológica Argentina https://doi.org/10.5710/102.054.0501

Novas, F.E., et al., Evolution of the carnivorous dinosaurs during the Cretaceous: The evidence from Patagonia, Cretaceous Research (2013), http://dx.doi.org/10.1016/j.cretres.2013.04.001 

Buffetaut, E. 2000A forgotten episode in the history of dinosaur ichnology; Carl Degenhardt’s report on the first discovery of fossil footprints in South America (Colombia, 1839). Bulletin de la Société Géologique de France 171: 137140Google Scholar

 

Historical perspective on the dinosaur family tree

Megalosaurus at Crystal Palace Park, London. From Wikimedia Commons.

In the 19th century, the famous Victorian anatomist Richard Owen diagnosed Dinosauria using three taxa: Megalosaurus, Iguanodon and Hylaeosaurus, on the basis of three main features: large size and terrestrial habits, upright posture and sacrum with five vertebrae (because the specimens were from all Late Jurassic and Cretaceous, he didn’t know that the first dinosaurs had three or fewer sacrals). These characteristics were more mammalian than reptilian. But new fossil findings from Europe and particularly North America forced to a new interpretation about those gigantic animals.

In 1887, Harry Govier Seeley summarised the works of Cope, Huxley and Marsh who already subdivided the group Dinosauria into various orders and suborders. However, he was the first to subdivide dinosaurs into Saurischians and the Ornithischians, based on the nature of their pelvic bones and joints. He wrote: The characters on which these animals should be classified are, I submit, those which pervade the several parts of the skeleton, and exhibit some diversity among the associated animal types. The pelvis is perhaps more typical of these animals than any other part of the skeleton and should be a prime element in classification. The presence or absence of the pneumatic condition of the vertebrae is an important structural difference…” Based on these features, Seeley denied the monophyly of dinosaurs.

Seeley’s (1901) diagram of the relationships of Archosauria. From Padian 2013

At the mid 20th century, the consensual views about Dinosauria were: first, the group was not monophyletic; second almost no Triassic ornithischians were recognised, so they were considered derived morphologically, which leads to the third point, the problem of the ‘‘origin of dinosaurs’’ usually was reduced to the problem of the ‘‘origin of Saurischia,’’ because theropods were regarded as the most primitive saurischians. A great influence on the views about the dinosaur origins was Alan Charig. He was Curator of Amphibians, Reptiles and Birds at the British Museum (Natural History), now the Natural History Museum, in London for almost thirty years. Charig thought that the first dinosaurs were quadrupedal, not bipedal. He based this on the kinds of animals that he and his colleagues found in the early Triassic localities of eastern and South Africa. He thought that forms such as ‘‘Mandasuchus’’ were related to dinosaurs, but that they had a posture intermediate between a sprawling and upright gait that he called ‘‘semi-improved” or ‘‘semi-erect’’.

Herrerasaurus skull. From Wikimedia Commons.

The discovery of Lagosuchus and Lagerpeton from the Middle Triassic of Argentina induced a change in the views of dinosaurs origins. Also from South America came Herrerasaurus from the Ischigualasto Formation, the basal sauropodomorphs Saturnalia, Panphagia, Chromogisaurus, and the theropods Guibasaurus and Zupaysaurus, but no ornithischians except a possible heterodontosaurid jaw fragment from Patagonia. The 70s marked the beginning of a profound shift in thinking on nearly all aspects of dinosaur evolution, biology and ecology. Robert Bakker and Peter Galton, based on John Ostrom’s vision about Dinosauria, proposed, for perhaps the first time since 1842, that Dinosauria was indeed a monophyletic group and that it should be separated (along with birds) from other reptiles as a distinct ‘‘Class”. In 1986, the palaeontologist Jacques Gauthier showed that dinosaurs form a single group, which collectively has specific diagnostic traits that set them apart from all other animals.

From Baron et al., 2017.

Phylogenetic analyses of early dinosaurs have  supported the traditional scheme. But back in March of this year, a paper, authored by Matthew Baron, David Norman and Paul Barrett, challenged this paradigm with a new phylogenetic analysis that places theropods and ornithischians together in a group called Ornithoscelida. The team analysed a wide range of dinosaurs and dinosauromorphs (74 taxa were scored for 457 characters), and they arrived at a dinosaur evolutionary tree containing one main branch that subdivides into the groupings of Ornithischia and Theropoda, and a second main branch that contains the Sauropoda and Herrerasauridae (usually positioned as either basal theropods or basal Saurischia, or outside Dinosauria but close to it). The term Ornithoscelida was coined in 1870 by Thomas Huxley for a group containing the historically recognized groupings of Compsognatha, Iguanodontidae, Megalosauridae and Scelidosauridae. The synapomorphies that support the formation of the clade Ornithoscelida includes: an anterior premaxillary foramen located on the inside of the narial fossa; a sharp longitudinal ridge on the lateral surface of the maxilla; short and deep paroccipital processes; a post-temporal foramen enclosed within the paroccipital process; a straight femur, without a sigmoidal profile; absence of a medioventral acetabular flange; a straight femur, without a sigmoidal profile; and fusion of the distal tarsals to the proximal ends of the metatarsals.

Of course, those results have great implications for the very origin of dinosaurs. Ornithischia don’t begin to diversify substantially until the Early Jurassic. By contrast, the other dinosaurian groups already existed by at least the early Late Triassic. If the impoverished Triassic record of ornithischians reflects a true absence, ornithischians might have evolved from theropods in the Late Triassic (Padian, 2017). The study also suggest that dinosaurs might have originated in the Northern Hemisphere, because most of their basal members, as well as their close relatives, are found there. Furthermore, their analyses places the origin of dinosaurs at the boundary of the Olenekian and Anisian stages (around 247 Ma), slightly earlier than has been suggested previously.

 

The dinosaur family tree Credit: Max Langer

More recently, an international team of early dinosaur evolution specialists, led by Max Langer, highlighted that the lack of some important taxa (for example, the early thyreophoran Scutellosaurus, the possible theropod Daemonosaurus, and the newly described Ixalerpeton and Buriolestes) may have a substantial effect on character optimizations near the base of the dinosaur tree, and thus on the interrelationships of early dinosaurs. The study did not find strong evidence to discard the traditional Ornithischia–Saurischia division. But they reintroduced a third possibility that was articulated in the 1980s but rarely discussed since: that sauropodomorphs and ornithischians may form their own herbivorous group, separate from the ancestrally meat-eating theropods. The Phytodinosauria hypothesis was coined by Robert T. Bakker in his book The Dinosaur Heresies: “Therefore all the plant-eating dinosaurs of every sort really constitute one, single natural group branching out from one ancestor, a primitive anchisaurlike dinosaur. And a new name is required for this grand family of vegetarians. So I hereby christen them the Phytodinosauria, the “plant dinosaurs”‘

References:

Max C. Langer, Martín D. Ezcurra, Oliver W. M. Rauhut, Michael J. Benton, Fabien Knoll, Blair W. McPhee, Fernando E. Novas, Diego Pol & Stephen L. Brusatte, Untangling the dinosaur family tree, Nature 551 (2017) doi; oi:10.1038/nature24012

Baron, M. G., Norman, D. B. & Barrett, P. M. A new hypothesis of dinosaur relationships and early dinosaur evolution.  Nature 543, 501–506  (2017).  doi:10.1038/nature21700

Padian K. Dividing the dinosaurs. Nature 543, 494–495 (2017) doi:10.1038/543494a

Padian K. The problem of dinosaur origins: integrating three approaches to the rise of Dinosauria. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, Available on CJO 2013 doi:10.1017/S1755691013000431 (2013).

Seeley, H. G. On the classification of the fossil animals commonly named DinosauriaProc. R. Soc. Lond. 43165171 (1887).

Huxley, T. H. On the classification of the Dinosauria, with observations on the Dinosauria of the Trias. Quarterly Journal of the Geological Society, London 26, 32-51. (1870).

Forgotten women of Paleontology: Margaret Benson

Margaret Jane Benson. Portrait in the Archives of Royal Holloway, University of London (RHC PH/282/13) From Fraser & Cleal, 2007

It is a truth universally acknowledged, that women has always work harder than men to gain some recognition. It was true in the 16th, and it’s true now. In “A Room of One’s Own”, Virginia Woolf explores the conflicts that a gifted woman must have felt during the Renaissance through the fictional character of Judith Shakespeare, the sister of William Shakespeare, and cites as obstacles the indifference of most of the world, the profusion of distractions, and the heaping up of various forms of discouragement. But not only in the Elizabethan times. In the Victorian times there was the common assumption that the female brain was too fragile to cope with mathematics, or science in general. In a letter from March 1860, Thomas Henry Huxley wrote to great geologist Charles Lyell FRS: “Five-sixths of women will stop in the doll stage of evolution, to be the stronghold of parsonism, the drag on civilisation, the degradation of every important pursuit in which they mix themselves – intrigues in politics and friponnes in science.”

Margaret Crosfield on a Geologists’ Association fieldtrip to Leith Hill with Professor Lapworth (From Burek and Malpas, 2007).

Women have played  various and extensive roles in the history of geology. Unfortunately, their contribution has not been widely recognised by the public or academic researchers. In the 18th and 19th centuries women’s access to science was limited, and science was usually a ‘hobby’ for intelligent wealthy women. Early female scientists were often born into influential families, like Grace Milne, the eldest child of Louis Falconer and sister of the eminent botanist and palaeontologist, Hugh Falconer; or Mary Lyell, the daughter of the geologist Leonard Horner. They collected fossils and mineral specimens, and were allowed to attend scientific lectures, but they were barred from membership in scientific societies. But by the first half of the 20th century, a third of British palaeobotanists working on Carboniferous plants were women. The most notable were  Margaret Benson, Emily Dix, and Marie Stopes.

Newnham began as a house for five students in Regent Street in Cambridge in 1871

Margaret Benson was born on the 20th October 1859 in London. Between 1878 and 1879, she studied at Newnham College Cambridge. After obtaining her BSc at University College London (UCL) in 1891, she started research on plant embryology.  In 1893, Benson was appointed head of the new Department of Botany at Royal Holloway College, the first woman in the United Kingdom to hold such a senior position in the field of botany. Her palaeobotanical research centred on the anatomy of reproductive structures, especially of Carboniferous pteridosperms and lycophytes. In 1904, she was among the first group of women to be elected as Fellows of the Linnean Society, and in 1912 she was appointed Professor of Botany at the University of London. Her major study on lycophyte fructifications was on the cones of the Sigillaria plant. She also speculated on the relationship between the Palaeozoic arborescent lycophytes and the Recent Isoetes, with the Triassic Pleuromeia as a possible intermediate form. She worked with ferns and cordaites and described a new species, Cordaites felicis. Benson’s work is characterized by careful description. One of her most important theoretical works concerns the phylogenetic significance of the sporangiophore in lycophytes, sphenophytes and ferns. After her retirement in 1922, she was encouraged by D. H. Scott to write up some of her earlier unpublished work on the root anatomy of the early Carboniferous pteridosperm Heterangium. She even continued with fieldwork when she was in her 70s. There is an unpublished manuscript in which she described a new fertile Rhacopteris that she collected from Teilia Quarry in North Wales in 1933. She died on 20th June 1936 at Highgate, Middlesex.

References:

H. E. Fraser and C. J. Cleal, The contribution of British women to Carboniferous palaeobotany during the first half of the 20th century, Geological Society, London, Special Publications, 281, 51-82, 1 January 2007, https://doi.org/10.1144/SP281.4

C. V. Burek (2007). The role of women in geological higher education – Bedford College, London (Catherine Raisin) and Newnham College, Cambridge, UK, Geological Society, London, Special Publications, eds Burek C. V., Higgs B. 281, pp 9–38

 

A brief history of the Spinosaurus.

One of the photographs donate by W. Stromer. Image from the Washington University in St. Louis

Despite its low fossil record, Spinosaurus is one of the most famous dinosaur of all time. This gigantic theropod possessed highly derived cranial and vertebral features sufficiently distinct for it to be designated as the nominal genus of the clade Spinosauridae. In 1910, E. Stromer went to his third paleontological expedition to Egypt. He arrived to Alexandria on November 7. He was initially looking for early mammals and planned visit the area of Bahariya, in the Western Desert, which has sediments from the Cretaceous era. But an expedition to the Western Desert needed the permission by the English and French colonial authorities and of course the Egyptian authorities. Although diplomatic relations with Germany were rapidly deteriorating, Stromer managed to get the permissions. He arrived to the Bahariya Oasis on January 11, 1911. After facing some difficulties during the journey, on January 17 he began to explore the area of Gebel el Dist, and at the bottom of the Bahariya Depression, Stromer found  the remains of four immense and entirely new dinosaurs (Aegyptosaurus, Bahariasaurus, Carcharodontosaurus and Spinosaurus aegyptiacus), along with dozens of other unique specimens. Stromer and Markgraf recovered the right and left dentaries and splenials from the lower jaw; a straight piece of the left maxilla that was described but not drawn; 20 teeth; 2 cervical vertebrae; 7 dorsal (trunk) vertebrae; 3 sacral vertebrae; 1 caudal vertebra; 4 thoracic ribs; and gastralia. This gigantic predator is estimated to have been about 14 m, with unusually long spines on its back that probably formed a large, sail-like structure.

1) Photograph of the right mandibular ramus of the holotype of Spinosaurus aegyptiacus Stromer, 1915 (BSP 1912 VIII 19), in lateral view. 2) Reproduction of Stromer’s (1915, pl. I, fig. 12a) illustration of the right mandibular ramus.

Due to political tensions before and after World War I, many of this fossils were damaged after being inspected by colonial authorities and not arrived to Munich until 1922. The shipping from El Cairo was paid by the Swiss paleontologist Bernhard Peyer (1885-1963), a former student and friend of Stromer. During the World War II, E. Stromer tried to convince Karl Beurlen -a young nazi paleontologist who was in charge of the collection- that he had to move the fossils to a safer place, but Beurlen refused to do it. Unfortunately, on April 24, 1944, a British Royal Air Force raid bombed the museum and incinerated its collections. Only two photographs of the holotype of Spinosaurus aegyptiacus were recovered in in the archives of the Paläontologische Museum in June 2000, after they were donated to the museum by Ernst Stromer’s son, Wolfgang Stromer, in 1995. These photographs provide additional insight into the anatomy of the holotype specimen of Spinosaurus aegyptiacus.

“Illustrations of the vertebrate “sail” bones of Spinosaurus that appeared in one of Stromer’s monographs. From Wikimedia Commons.

In his original monograph, Stromer emphasized the peculiar character of the teeth of this unusual theropod. Because of their morphological convergence with those of crocodilians and other fish-eating reptiles, isolated spinosaurid teeth have frequently been misinterpreted. It appears that Baryonyx-like teeth were collected by Gideon Mantell in Sussex around 1820. Georges Cuvier was the first to publish an illustration of the four teeth from Tilgate Forest. These teeth, however, were generally considered as belonging to crocodilians, and when Richard Owen erected the taxon Suchosaurus cultridens to designate them he placed it among the crocodiles. Even when Owen realized that these teeth were peculiar in many respects and hinted at possible affinities with dinosaurs, he persistently classified Suchosaurus as a crocodilian, an interpretation that was accepted by most subsequent authors.

Although Stromer’s original description of Spinosaurus aegyptiacus was published in 1915, a more complete detailed picture of its anatomy, evolution, and biogeography only begun to emerge in recent decades.

 

References:

HONE, D. W. E. and HOLTZ, T. R. (2017), A Century of Spinosaurs – A Review and Revision of the Spinosauridae with Comments on Their Ecology. Acta Geologica Sinica, 91: 1120–1132. doi: 10.1111/1755-6724.13328

Smith, et al. “NEW INFORMATION REGARDING THE HOLOTYPE OF SPINOSAURUS AEGYPTIACUS STROMER, 1915.” J. Paleont., 80(2), 2006, pp. 400–406

Geomythology: On Cyclops and Lestrigons

Pellegrino Tibaldi, The Blinding of Polyphemus, c. 1550-1

In Greek mythology giants are connected to the origin of the cosmos and represent the primordial chaos which contrasts with the rationality of the Gods. They were the sons of the earth (Gea) fertilized by the blood of the castrated Uranus (Heaven). In that chaotic, primal era, strange creatures proliferated, such as the Cyclopes, and the Centaurs. Lestrigons, a tribe of man-eating giants, appears in Homer’s Odyssey. Polyphemus, is one of the Cyclopes also described in Homer’s Odyssey. Greeks believed that the Laestrygonians, as well as the Cyclopes, had once inhabited Sicily.

But the ancient myth of giants is a common element in almost all cosmogonies. In Scandinavians legends, the blood of the giant Ymo formed the seas of th Earth, and his bones formed the mountains. In Peru, Brazil, and Mexico, the giants are part of the folk tradition. Judaism, more precisely, the Talmud and the Torah, converges with Genesis on the origin of the giants.

Laestrygonians Hurling Rocks at the Fleet of Odysseus

The discovery of huge fossil bones has always stimulated the imagination of local people, giving rise to legends. We found direct reference in the works of Herodotus which mentions the large bones of the giant Orestes recovered in Acadia, or even Virgil in his Georgics speaks of gigantic bones. In the sixteenth century, Italian historians, such as the Sicilian Tommaso Fazello, used the sacred texts to demonstrate that the first populations of many islands of the Mediterranean (among them Sicily and Sardinia), were of giants. At the same time, the first notices of South American fossils were reported by early Spanish explorers. These fossils were interpreted as the remains of an ancestral race of giant humans erased from the face of the Earth by a divine intervention. Fray Reginaldo de Lizarraga (1540-1609) also wrote about those “graves of giants” found in Córdoba, Argentina.

The case of Filippo Bonanni, an Italian Jesuit scholar, is very curious. He used the topic of the giants as an element in support of his theory of the inorganic origin of fossils. He properly rejects the myth of giants, but wrongly identify the nature of fossils. The most strong supporter for the organic origin of fossils was the italian painter Agostino Scilla. He published only one scientific treatise: La vana speculazione disingannata dal senso, lettera risponsiva Circa i Corpi Marini, che Petrificati si trouano in vari luoghi terrestri (The vain speculation disillusioned by the sense, response letter concerning the marine remains, which are found petrified in various terrestrial places). The aim of the work was the demonstration that fossils, which are found embedded in sediments on mountains and hills, represent the remains of lithified organisms, which at one time lived in the marine environment. The text was later translated to Latin and it was written as a response to a letter sent to him by Giovanni Francesco Buonamico, a doctor from Malta.

Femur of Mammuth interpreted as a bone of a giant and preserved as a relic in St. Stephen’s Cathedral in Vienna.

Madrisio (1718) is one of the first authors in Italy to suggest that much of this giant bones may be referred, without problem, to elephants from the past. But te real interpretative turning point takes place with the influential work of the Hans Sloane, who stressed the importance of a comparative study of the bones in various vertebrates. Applying this method, he demonstrated how the big bones and teeth found in sediments or in caves are nothing more than remains of cetaceans and large quadrupeds, remarking on the major anatomical differences between humans and other known vertebrates. Among the few precursors of Sloan, the Italian naturalist Giovanni Ciampini in 1688, using direct comparisons with the famous elephant exhibited in Florence in the Medicean Museum, was able to correctly interpret the bones found at Vitorchiano near Viterbo, initially attributed to gigantic men.

References:

Marco Romano & Marco Avanzini (2017): The skeletons of Cyclops and Lestrigons: misinterpretation of Quaternary vertebrates as remains of the mythological giants, Historical Biology, DOI: 10.1080/08912963.2017.1342640

The American incognitum and the History of Extinction Studies

 

Georges Cuvier (1769 -1832) and the painting of Charles Wilson Peale’s reconstruction of the American incognitum

Extinction is the ultimate fate of all species. More than 95% of all species that ever lived are now extinct. But prior to the 18th century, the idea that species could become extinct was not accepted. However, as the new science of paleontology began bringing its first major discoveries to light, researchers began to wonder if the large vertebrate fossils of strange creatures unearthed by the Enlightenment explorers were indeed the remains of extinct species.

In 1739, French soldiers under the command of Baron Charles le Moyne de Lougueuil recovered a tusk, femur, and three curious molar teeth from Big Bone Lick, Kentucky, a place known in several American Indian narratives. Lougueuil sent these specimens to the Cabinet du Roi (Royal Cabinet of Curiosities) in Paris. In 1762, Louis Jean-Marie Daubenton, a zoologist at the Jardin du Roi concluded that the femur and tusk from the Longueuil’s collection were those of a large elephant, the “Siberian Mammoth,” but the three molars came from a gigantic hippopotamus.

Molar collected at Big Bone Lick in 1739 and described in Paris in 1756. (Georges Cuvier, Recherches sur les ossemens fossiles)

By the early 18 century it was inconceivable for many researchers that a species could be vanished. Naturalist Georges-Louis Leclerc de Buffon, wrote in 1749 about the extinction of marine invertebrates, but he adopted Daubenton’s view that the Siberian mammoth and the animal of the Ohio, known as the American incognitum, were both northern forms of the extant elephant rather than a vanished species. British anatomist William Hunter was the first to speculate that these remains might be from an extinct species. In 1799, the discovery of an American incognitum femur from Quaternary deposits in the Hudson River Valley led to excavations organized by Charles Wilson Peale. In 1801, the excavations resulted in the recovery of an almost complete skeleton. Peale reconstructed the skeleton with help from the American anatomist Caspar Wistar, and the displayed the mounted skeleton in public in December of that year.

In 1806 Georges Cuvier resolved the controversy about the  American incognitum demonstrating that both the Siberian mammoth and the “animal de l’Ohio” were elephants, but of different species. He described the Ohio elephant as a mastodon and he reached the conclusion that probably represented an extinct species. Cuvier was also the first to suggested that periodic “revolutions” or catastrophes had befallen the Earth and wiped out a number of species. But, under the influence of Lyell’s uniformitarianism, Cuvier’s ideas were rejected as “poor science”. The modern study of mass extinction did not begin until the middle of the twentieth century. One of the most popular of that time was “Revolutions in the history of life” written by Norman Newell in 1967.

 

References:

Macleod, N. The geological extinction record: History, data, biases, and testing. Geol. Soc. Am. Spec. Pap. 505, (2014), DOI: 10.1130/2014.2505(01)​

Marshall, Charles R., Five palaeobiological laws needed to understand the evolution of the living biota, Nature Ecology & Evolution 1, 0165 (2017), DOI: 10.1038/s41559-017-0165 .

Dinosaur Island

 

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Batman #1, New 52

In Batman #1 in the New 52, we see a giant animatronic dinosaur kept in the Batcave as a trophy. The T. rex is a reminder from an early adventure on Dinosaur Island (Batman #35, from June 1946). In that story, Murray Wilson Hart, a wealthy industrialist creates an amusement park named Dinosaur Island, filled with robot replicas of dinosaurs and robotic cavemen, but a criminal takes control of the mechanical dinosaurs and attacks Batman and Robin. Eventually, the dynamic duo defeat the criminal and Batman take the T. rex as a souvenier.

A second and definitive version of Dinosaur Island appeared in the Spring 1960 issue of Star-Spangled War Stories #90. Based on The Land That Time Forgot by Edgar Rice Burroughs, the saga follows a group of American soldiers, stranded on an uncharted island during the Pacific War which they discover is populated by dinosaurs. The original novel was set on World War I and is a reminder of Jules Verne’s novel Journey to the Center of the Earth, and Arthur Conan Doyle’ s The Lost World.

Cover of The War that Time Forgot by Ross Andru & Mike Esposito

Almost three decades before Verne’s Journey to the Center of the Earth, Rodolphe Töpffer (1799- 1846) published a peculiar geological tale. Töpffer was a Swiss author considered the first comics artist.  In Journey to the Center of the Earth (1864), Jules Verne incorporated the knowledge of the time. Verne was inspired by Charles Lyell’s Geological Evidences of the Antiquity of Man and Lyell’s earlier ground-breaking work Principles of Geology.

Arthur Conan Doyle began to write The Lost World in 1911. One year later it was published in book form by Hoddar and Stoughton. By that time he already was one of the most popular author around the globe, thanks to his most iconic creation, Sherlock Holmes. Probably, one of the most influential works in Doyle’s novel was “Extinct Animals” by Ray Lankester,  Director of the Natural History Museum. The Lost World has much in common with Journey to the Centre of the Earth, and has contributed significantly to the fascination with dinosaurs and pterodactyls. Even more, the first full-length science fiction film was based on Conan Doyle’s novel.

 

References:

Conan Doyle, A. 1912. The Lost World. Hodder & Stoughton, London.

Verne, J. G. 1864. Voyage au centre de la Terre. Pierre Jules Hetzel, Paris.

Edgar Rice Burroughs, The Land That Time Forgot,  Blue Book Magazine, 1918

Batman #35, DC Comics, 1946

Star-Spangled War Stories #90, DC Comics, 1960