Dinosaurs Among Us: The Missing Link

Birds are a unique group of creatures. They don’t seem to quite fit the bill for any other major group of animals with which we are familiar.

They are warm blooded, but don’t suckle their offsprings like mammals. They lay eggs, but have feathers instead of scales like reptiles. They don’t swim in the water and secrete slimy mucous all over themselves like amphibians. They have wings, but not segmented legs and shells like insects. They really are an unusual bunch.

It has long puzzled scientists how large flying animals first took to the air. By the late 19th century, dinosaurs achieved their celebrated status mostly due to the work of the rather aggressive palaeontologist, Richard Owen, who notoriously published many of his colleagues’ work as his own. He was known to have assembled a large collection of dinosaurs for the British Museum. 

In Solnhofen, Germany, lies one of the most beautiful fossil beds in the world. In the age of the dinosaurs, the site was a shallow reef teeming with life. Horseshoe crabs skated along the bottom, fish roamed the waters, shrimps with weirdly long arms snapped at little seastar-looking floating crinoids, flying reptiles roamed the skies. As with many beautiful things, this rich collection of fauna did not persist for long. As the reef grew, it emerged from the ocean and formed small isolated pools of water. The fragmented habitats became increasingly salty and oxygen-poor, suffocating all animals that lived within them.

Modern horseshoe crabs like this ancient counterpart, Mesolimulus walchi, are harvested for their haemolymph, which are used in pharmaceutical testing. These animals from the Solnhofen Limestone are morphologically practically unchanged since emerging about 400 million years ago. Photo courtesy of Andy Tan ’21.

Fortunately for us, these conditions are ideal for the preservation of fossils. Animals that died on land and fell into the lakes were also remarkably well-preserved. Darwin was a contemporary of Owen. After the publication of The Origin of Species, Darwin was soon bombarded by criticisms from his colleagues about a missing link in his theory.  If animals gradually changed over time into new forms, as his colleagues were quick to note, there ought to be intermediate forms between animals. Animals with wings would have evolved from animals without. The fossil record, however, appeared to be resolutely silent on  these intermediate transitional forms. This conundrum became a painful source of embarrassment and anxiety for Darwin for a very long time. He wrote:

“Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and gravest objection which can be urged against my theory. The explanation lies, as I believe, in the extreme imperfection of the geological record.”

In 1861, just two years after the publication of The Origin, a key piece of evidence in the dinosaur-bird conundrum was found. A single fossil feather was found in Solnhofen. And perhaps a little prematurely, it was described as Archaeopteryx, meaning “old wing”. A final piece of the biggest puzzle in Darwin’s career was in place, demonstrating that descent with modification is the way in which life evolved on Earth. 

An exquisite replica of the Archaeopteryx lithographica from the Solnhofen Plattenkalk, Germany, present in the Wesleyan Joe Webb Peoples Museum Collection, with detailed soft tissue preservation indicating the presence of feathers as in a bird-like creature, but a tail skeleton as in reptiles.

In the same year, a complete skeleton of the Archaeopteryx was unearthed. It resembled a chimaera – an intermediate form between reptiles and a modern bird. It has a beautiful feathery plumage, at that time thought to be limited to birds, but it also has jaws lined with sharp teeth, and a long bony line of vertebrae in its tail. Archaeopteryx was not a modern bird, but it clearly was an animal that took to the skies, although there still is debate about how able a flyer it was. Thomas Henry Huxley proposed in the 1860s-1870s  that dinosaurs were more like big, non flying birds than like lizards, and John Ostrom (Yale) discovered much evidence in support, and was an enthusiastic proponent (1970s-1990s). In view of Archaeopteryx, and the fact that quite a few dinosaurs were feathered, as now known from numerous finds in China, scientists are now convinced that birds not only are descended from dinosaurs, but are, in fact, dinosaurs. 

Wesleyan’s natural history collection houses almost 200 taxidermy birds, many dating back to the late 1800s. We have engaged a professional preparator to restore the birds to their former beauty. Having sat in our collections since the 1800s, not always under the best conditions for preservation, many of the delicate specimens were crumbling with age, and notoriously challenging to restore. These marvellous avian dinosaurs will soon make their exodus from exile to various campus locations in a series of touring exhibitions. Get a sneak peak into these living dinosaurs!

Professor Ann C. Burke’s favourite chicken toy, Gallus gallus plasticus, registering displeasure at having to share her territory with a newly restored Short-eared Owl, Asio flammeus. Photo courtesy of Wisly Juganda ’20.

The Wesleyan collections also house some of the finest of dinosaur tracks in the world, from the Connecticut River Valley, originally seen as tracks of giant birds by Edward Hitchcock in the 1830s. Recent studies used guinea fowls and ostriches as experiment subjects to study the tracks left by dinosaurs. The similarity between these tracks is astounding. The prevalence of these tracks in Connecticut, which has possibly the densest record of such fossils from the early Jurassic in the world, has seen the Eubrontes sp. being listed as the Connecticut State Fossil.  Eubrontes was left by a large bipedal dinosaur, possibly related  to  Dilophosaurus, which would more appropriately be called a non-avian dinosaur.

Eubrontes sp. tracks on display in the Elxey Science Centre. Note the three-toed form of these non-avian dinosaur tracks, similar to those made by chicken feet. Photo courtesy of Andy Tan 21.

In science,  facts trump it all. Dogmas and laws get scoffed at and discarded in the face of new evidence. It is a bold practice that acknowledges the limits of human knowledge, and one that owns up to, and moves on from, its mistakes. Even veteran scientists are often confronted with new discoveries that fundamentally shift their worldview. Join us in childlike wonder in encountering oddities that will surprise you at every turn in the Joe Webb Peoples Natural History Museum on Level 4 of Exley.

Cover photo: Detail of the pennaceous feathers of Pharomacrus moccino moccino, the Quetzal,  from Central America. Courtesy of Wisly Juganda ’20.

Jurassic Fish: Salted Sardines in the Rocks

Driving along the highways of Connecticut, many don’t realise that the rocks by the side of the roads holds a looking-glass to one of the most famous times in geological history – the Jurassic Period.

The natural landscape of the Newark and Hartford Basins in Connecticut, as it was about 200 million years ago, would look very unfamiliar. The land that we know and on which we live today was at times a desert, at other times submerged under a series of lakes. These were not mere shallow pools of water, but lakes so deep that the waters could become stratified, that is, form distinct layers. The shallows were aerated by wind and tide, and teeming with life. The deeper layers were so far below the surface that oxygen could not be mixed in from the atmosphere, and these waters lacked oxygen for much of the time, so that fish could not live there. The lakes went through cycles of flooding and drying, and were connected during periods of flooding.

More than 6 genera and 13 species of fish have been found in Connecticut. Wesleyan’s collections hold a large number of an especially puzzling and intriguing fossil genus,  Semionotus. Even after 150 million years, the glossy sheen on the scales of these fish are so well-preserved that visitors often ask if they are lacquered. The excellent preservation allows researchers to see the large array of shapes of body shapes and dorsal scales, suggesting that these fish may have undergone what scientists often call the Founder’s Effect.

Fossil deposits are found only in some strata in the rocks, with gaps corresponding between them, representing the duration of the flood-dry cycles in these Jurassic rift basin lakes. Fossils are only preserved from the stages of the cycles when deeper parts of the lakes lacked oxygen, as seen by the microlamination of the shales: no animals were burrowing to disturb this fine layering. By looking closely at the fossils from these intermittently connected lakes, scientists realized that Semionotus commonly displayed a large morphological diversity soon after they were introduced into a large continuous habitat, formed by large scale flooding of the basin.

 

Three specimens from our collections showing variability in body shape and dorsal ridge scale morphology. Currently on view in the Joe Webb Peoples Museum on Level 4 of Exley Science Centre. Photo courtesy of Andy Tan ’21.

This phenomenon is observed today in a number of settings, including  the most famous example, Darwin’s Finches from the Galapagos Island. The Galapagos are volcanic islands that had no birds before the arrival of the mainland finches. To minimise competition, the finches quickly evolved into many species that utilise very different resources on the island. Some fed on seeds, other prefer insects, cactus berries, nectar, worms in hollow trees and so on. The empty ecological niches on the islands provided the birds with an opportunity to diverge into different lifestyles that facilitated rapid speciation, whereas the mainland species remained as a single species, which could not outcompete other birds that had already filled corresponding ecological niches.

 

The huge diversity of beak shape, colour and body size in Darwin’s Finches demonstrates the  array of ecological resources which they use. Introduction of bird feeders in recent years have reversed the divergence of beak shape in several finch species.

 

Founder’s Effect commonly provides a more hopeful outlook on anthropogenic change in the modern times, and brings into discussion whether new environments caused by human activities might drive some species to increase morphological diversify. If this were true, the loss of species due to human activities might be offset.

Cover photo: Semionotus sp. scales detail from the Wesleyan Joe Webb Peoples Museum collections. Photo courtesy of Andy Tan ’21.

Oeningen Formation: Science, Sink or Swim

Science was not like it is today in the 18th and even 19th century: things people used to do in science at that time – not too long ago -may  appear very odd to us. In Wesleyan’s collections lie several keystone artifacts to this rather fascinating episode in history.  Before science (as we consider it now) existed, people thought  that living species of animals had always existed and will always exist – the idea that there was such a thing as ‘extinction’ was not realized. It was not until the 1830s that one of the most important figures in the history of paleontology played a role in awakening the world of science to the actuality of extinction. She was Mary Anning, the daughter of an English cabinet maker, who discovered groundbreaking specimens pivotal to this paradigm shift, but she was not given credit for her important contributions during her life time.

Ichthyosaurus communis, a replica of a fossil specimen found by Mary Anning on the coast of Lyme-Regis, in Southern England; third floor, Exley Science Center.

Even when the celebrated star in paleontology, Georges Cuvier, published a first authoritative paper on extinctions in 1879, the general public did not take it lightly that Divine Providence was  doubted by the idea of extinction of creatures, which had been designed and made by that Providence. Even when described by a man who mesmerized the European public with the fascinating animals he put together from a box of disarticulated bones, the community did not warm up to the concept of extinction. Why would God create animals only to wipe them out later? This idea was contrary to the prevalent notion that everything created has its permanent, perfectly designated place and purpose in the world, fitting  into the Great Chain of Being.

Cuvier’s brainchild – the osteology collection in the Natural History Museum in Paris. The spectacle is impressive today, and one can easily be imagine that it was  mind-blowing in the 1800s.

The Oeningen Formation in Germany contains a vast trove of beautifully preserved fossils, including some spectacular plant leaves, with leaf veins visible, and what have been called ‘perhaps the richest insect deposits in Europe’, dating back to the late Miocene (~6-11.5 million years).  In the 1700s, long before the research by Mary Anning or Georges Cuvier, an odd fossil was dug up from these sediments. The identity of the remains was an enigma. To the contemporary scholars, this could only be the remains of something that still existed on Earth, because the concept of extinction had not yet been worked out. Swiss scholar – scientist was not a job title back thenJohann Jakob Scheuchzer gave the scholarly community the most obvious answer to this conundrum in 1726, illustrating the tension between science and religion. This must have been “The Man Who Witnessed the Biblical Flood”, in Latin ‘Homo diluvii testis’.

Michelangelo’s Sistine Chapel Ceiling fresco panel depicting the Great Flood according to the Bible. All living things were killed except two of each kind, and the family of Noah, who found grace in the eye of God. Which of these men were fossilised?

Other naturalists expressed doubts on the human origins. Johannes Gessner (1758) though it was a catfish, the Dutch naturalist Petrus Camper (1777) thought it was a lizard – at that time, the distinction between amphibians and reptiles had not been made. Georges Cuvier looked at the fossil in 1811 (at which time it was on display at Teyler’s Museum in the Netherlands -where it still is). He removed sediment covering part of it so he could see a larger part of its skeleton, including its front legs. This was a man who boasted he could reconstruct an animal from a single tooth, and he quickly determined that the fossil was that of a giant salamander which no longer lived on Earth. The fossil was named Salamander scheuchzeri by Friedrich Holl (1831), then given a new generic name, Andrias, in 1837 (by Johann Jakob von Tschudi). Perhaps taking a jive at Scheuchzer’s ideas, the new name, Andrias scheuchzeri, meant “image of man of Scheuzer”. The Joe Webb Peoples Museum on Level 4 of Exley houses a cast of this giant salamander, measuring about 3 feet in length.

Picture of Homo diluvii testis as published by Scheuchzer

 

Andrias scheuchzeuri, an extinct giant salamander once thought to be the remains of the man who witnessed The Flood. Photo courtesy of Andy Tan ’21.

Science has come a very long way in a very short period of time, but people are still catching up.  Science ‘as we know it’ has had a place within the last 10% of the ~ 5000 years of recorded history only. It has only been 300 years since we first looked at the Moon and decided that there are no people living on it. It has only been less than 100 years since the advent of modern medicine. 50 years since the first moon landing. 15 since the first human genome sequenced. Today, we still sometime struggle with beliefs that fossils are the work of the Devil.

The Oeningen Lake Beds from where our salamander hails is one of the world’s richest site for plant and insect fossils. Note the intricate venation still preserved. Photo courtesy of Andy Tan ’21

Living in a time when the authority of science as a source of empirical truth (or even the existence of such a thing as ’empirical truth’) is undermined by political and religious leaders, the increased understanding provided by scientific pursuit is under daily threat.

Come to the Joe Webb Peoples Museum of Natural History on Level 4 of Exley, and feast your eyes on our fossils with a beauty superseding any text written in stone.

We stand on the shoulders of Giants…

Cover photo: Andrias scheuzeri spine details from the Wesleyan Joe Webb Peoples Museum natural history collection. Photo courtesy of Andy Tan ’21.

Deinotherium: Stranger Than Fiction

Working with fossils, it’s not difficult to think that science is often stranger than fiction.

Wesleyan’s new star – our Glyptodon – is something that defies our every expectation of an armadillo. With her domed carapace, exquisite scutes and odd bone projections on her cheeks, she looks like a creature from a science fiction film.

Another odd piece that we recently plucked out of the Penthouse of Exley was another odd customer. With short proboscis – trunk-like structures like that of an elephant, and an unusual, downward curving pair of tusks, she was quite an odd sight.

 

The uncrating of the Deinotherium jaw and tusks from its 60 year-old crate. Dusty. Photo courtesy of Miah Tran ’21.

 

This creature has a rather unfortunate name. She was called “terrible beast”, derived from the Ancient Greek, deinos meaning “terrible” and therion meaning “beast”. She was a Deinotherium, a giant extinct elephant relative that lived from the middle Miocene (about 12 million years ago) to the middle Pliocene (about 3 million years ago). There is no consensus, even today, as to how these beasts used their peculiar-looking tusks that apparently serve no apparent purpose apart from prodding themselves when they nod their heads.

 

Artist reconstruction of Deinotherium featuring “self-prodding” tusks and oddly short proboscis. Illustration courtesy of LD Austin.

 

Nevertheless, this creature is by no means the oddest thing the fossil record has in stock. Evolution is a large series of experiments in nature where many body plans have been put to test. The Burgess Shale collection at Wesleyan holds some of the  legendary and mind-blowingly strange fossils from the middle Cambrian, about 550 million years ago. Stranger things lurk on Level 4 of Exley in the Joe Webb Peoples Museum of Natural History awaiting your discovery.

After the summer, this grand Deinotherium will join the Glyptodon on the museum’s developing series of exhibits around campus. Leave a comment and tell us where you would like to see this animal on campus!

 

Two inquisitive youngsters paying homage to the formidable Deinotherium in the former Wesleyan Museum. Photo courtesy of Special Collections and Archives.

 

The Deinotherium skull and lower jaw placed together, while we are planning for the best way and place  to exhibit them, in Wesleyan machine shop. Together again after 60 years of storage in separate crates, first in the tunnel under Foss Hill (1957-1970), then in the penthouse of Exley.

Cover photo: Deinotherium teeth detail showing premolars used for crunching. Photo courtesy of Andy Tan ’21.

 

Our Star Glyptodon

After almost a year of collaborative efforts, our Glyptodon, a copy of an original in a museum in Dijon, France, is finally in her place. Come gaze at her gorgeous scutes and adoring smile – it’s there, look carefully. Her favorite spot outside the Science Library, in the lobby of Exley, is decorated with pebbles that resemble those in the bed of the River Lujan, by which she was found in 1846. The screen next to her will tell you about her tumultuous journey from being hunted, to being neglected to finally being loved by all at Wesleyan.

 

The skull of our Glyptodon is a resin replica made by Gaston Design. It was painted to look like fossilised bone, and to match the rest of the cast. The original skull and feet are still missing. Photo courtesy of Olivia Drake.

 

The biological sex of our Glyptodon cannot be determined from the skeletal remains. In honor of the many hidden women figures in the sciences, and in a tribute to a tradition practised by Sir David Attenborough, we assume that our Glyptodon was female.

We are very heartened that our hard work has been appreciated by the community in many ways. Here are some rather comical, but nonetheless appreciated reactions to our GlypGlyp.

 

Alison Gross’18 shows her appreciation of Glyptodon. Video courtesy to Xandra Ellin’18.

 

A little dated, but we couldn’t resist adding this photo of a young prospective Glyptodonologist from the early 1900s to our list of people appreciating the Glyptodon. Photo courtesy of Wesleyan Special Collections and Archives.

If you are wondering, there is so much more in the Wesleyan storage places from where Glyptodon came: she is a mere tip in the sea of icebergs in our collections. The Joe Webb Peoples Museum of Natural History collections on Level 4 of Exley holds over 100,000 fossils, minerals and meteorites. Many of these are world-class specimens that are held by few other institutions in the world. Come feast your eyes on some of nature’s most elusive treasures.

Don’t forget to propose a name for our Glyptodon so that we know what to call her when we walk by.

 

A shout out to everyone who brought the exhibition to fruition. Dr Ellen Thomas and Dr Ann C. Burke, for their mentorship and expert insight. Bruce Strickland, our Glyptodon Engineer, for mounting the pieces together and advising on restoration. James Zareski, for building her a marvellous pedestal like the one on which she used to stand  60 years ago. Joel Labella, for advice and enthusiastic help in restoration. And in a flourish of self-praise, Master Glyptodoners, Yu Kai Tan and Andy Tan restored the cast to its former glory.

 

The Glyptodon Crew. From left to right: Joel Labella, Bruce Strickland, James Zareski, Yu Kai Tan (me), Andy Tan, Dr. Ellen Thomas, Dr Ann C. Burke, David Strickland. Photo courtesy of Olivia Drake.

 

Cover Photo: Frontal portrait detail of Glyptodon skull. Photo courtesy of Olivia Drake.

Swimming with Monsters

 

Would you like to snorkel with giant predator reptiles the size of a small airplane?

Visit Level 3 of Exley Science Centre, where these spectacular beasts adorn our walls. And fear not, they are models, and the originals from which they are made have been petrified in stone for more than 100 million years.

 

Magnificent beasts revived from obscurity. From left to right: Plesiosaurus dolichodeirus, Rhomaleosaurus macroocephalus, Temnodontosaurus platyodon. Photo courtesy of Andy Tan ’21.

These fossil casts of animals which many children grew up knowing as Plesiosaurus and Ichthyosaurus have been plucked out of the obscurity of storage in the penthouse of Exley, where they had been collecting dust and mildew since 1957. Restoration efforts have brought these creatures back to their ferocious selves.

 

Sculpting a large missing chunk from the Mosasaurus hoffmani mandible back in place with plaster. Mosasaurs were marine lizards; we still need to find a place for this large specimen. Photo courtesy of Andy Tan ’21.

 

Once apex predators of the Mesozoic – the Age of the Dinosaurs – they have often been misrepresented as swimming dinosaurs. Ichthyosaurs were powerful swimmers that dived to great depths,  their eyes  protected from the high water pressure by bony shields. Plesiosaurs have such bizarrely long necks that their discoverer, a village girl named Mary Anning, was at some time accused by Georges Cuvier of fabricating a fossil by combining disparate body parts.

European scientists from colonial times are notorious for assuming the property of the conquered as theirs. Many of the world’s best fossils reside in institutions in Paris and London. In the 1800s, American professor Henry A. Ward decided that paleontologists in the US deserve to study  the best fossils in the world without having to travel across the Atlantic, a long and expensive trip, and suffer bouts of seasickness. Apparently, rock folks weren’t that good with the choppy waters. He traveled to Europe and made copies of some of the most celebrated fossils of his time, and sold them to institutions in the United States.

 

A spread from Henry A. Ward’s catalogue of fossil casts from the 1800s showing two of the Plesiosaur specimens now on display on Level 3 of Exley.

 

The World’s Columbian Exhibition of 1893 in Chicago showed a full series of these marvellously rendered casts, which were later showed as featured exhibits in the Field Museum. Wesleyan acquired a full series of these casts for its Natural History Museum in 1871 as a donation from Orange Judd. When the museum closed in 1957, they were crated and tossed unceremoniously into tunnels and penthouses around campus, where they remained for 60 years, until they were recently brought into the daylight once more.

 

An unfamiliar sight to most Wesleyan residents today, this is a photo of the natural history museum in Judd Hall, until 1957. Photo courtesy of Special Collections and Archives, Wesleyan University Library.

 

Cover photo: Spinal processes of Rhomaleosaurus macrocephalus. Photo courtesy of Andy Tan’21.

The Glyptodon (and other casts): Shining New Armor

Our star Glyptodon is getting a new coat of paint after we stripped her of a large quantity of 60 year-old dust, with plenty of elbow grease. As with the other Ward Casts in our collection, she will be repainted with archival artist acrylic paints. The color of our Glyptodon is rather bleached from the harsh  lighting during its days in the Wesleyan Museum (1871-1957). Archive photos from Special Collections and Archives at Olin Library at Wesleyan University, and photos of the same cast on public display in the Manitoba Museum show that she once sported a shinier and darker coat.

The sex of our Glyptodon cannot be determined from the material we have on hand. Hence according to a fairly recent tradition in assigning sex to these undetermined specimens in major museums and documentary productions, we are assuming that she was female when she lived. #davidattenborough

The Glyptodon on display in Judd Hall, at an unknown time before the closure of the Wesleyan Museum in 1957. She appears to have once sported a much darker carapace than she does today. Image from Wesleyan University Library, Special Collections & Archives.

A  chunk of missing plaster was taken out of the right side of the creature, at some time during its long storage. We filled the shallow hole with Plaster of Paris and hand-sanded it to match the contour of the dome carapace. With a traditional Chinese stone seal carving knife, we carved the scutes (bony plates or osteoderms) on the Glyptodon into the newly filled plaster. Some artistic license went into the reconstruction of the damaged part, which we adjusted to the surrounding area, as our  research of Glyptodon scutes did not yield information pertinent to their restoration. However, each species of Glyptodon had its own unique pattern of scutes.

A traditional Chinese seal stone carving knife is used to etch and carve new scutes onto the fresh plaster fill-in. Measures are taken to ensure the interpretive restoration fits in well with the morphology of the old scutes.

To match the color of the original cast, we performed a spot test on and around the plaster fill. This spot was chosen in part because we were excited and a tad anxious to see how the restoration would turn out. Using an old worn-out brush with stiff bristles to stipple various shades of browns and darks over an undercoat of yellow ochre, we painted in the plaster restoration. It turned out rather satisfactory, with the color not  distinguishable from the surrounding areas.

Many more tubs of paint away from completion, the results are looking  encouraging. In the mean time, we are also working on restoring a cast of the holoytype of Mosasaurus hoffmanni, a source of political drama and contention between European governments. But more about that next time. – or see here for a first start of the saga of the mosasaur Our cast of this fossil was in a tremendously lamentable state when we found it in the penthouse of Exley. #déjàvu

Still far from being finished, our Mosasaurus hoffmanni is beginning to look rather spiffy after about 30 hours of work. Note the unpainted plaster fill-in on the lower mandible and the makeshift palette on the upper left. (Photo courtesy of Andy Tan ’21)

Large pieces of plaster were missing, including a broken tooth and a missing piece from the broken mandible the size of a tortilla chip. We have since sculpted the missing parts in plaster, which happens to be a notoriously challenging medium to work in. Once prepared, the plaster is workable for only 15 minutes before it cures, and it has a creamy consistency akin to that of mashed potatoes. Once the plaster cures, it is slowly hand-sanded to shape and painted with a matching colour mix.

A cling film is used to guide the plaster into place and hold the unstable medium in place for shaping and curing. The fill-in will later be carved and hand-sanded to shape. Other major plaster restorations can be seen in the background. (Photo courtesy of Andy Tan’21)

The careful reconstruction of these fossil casts play a significant part in reconstructing the history of paleontology. When fossil hunting was a trending field of study in Europe in the late 1800s, fossil specimens were found all over Europe in large numbers, with paleontologists in the US catching up in the late 1800s, specifically with the construction of railroads into the US west. In the 1860s, a visionary in the field, Henry A. Ward, an American geologist and naturalist and professor at Rochester University (and the founder of the present Ward’s Science company) , felt that the US public missed out on the opportunity to see the  most famous fossils, and made  an effort to provide access for scholars in the US to important fossil material: in 1866 he published his Catalogue of Casts of Fossils from the Principal Museums of Europe and America. His ambition and foresight laid the foundation for a generation of American paleontological work and public awareness on evolutionary theory based on these materials. Orange Judd provided funding to buy the complete series of casts when the Orange Judd Hall was finished in 1871, including the Giant Ground Sloth, Megatherium cuvieri, and Plesiosaurus cramptoni, 22 ft long; sadly, these two giant casts have  been lost at the dissolution of the Wesleyan Museum.

Not a dinosaur! And not a Jurassic animal either. An example of a sensationalist reconstruction. Mosasaurs are dominant predatorial marine lizards of the Late Cretaceous, many millions of years after the Jurassic. This one had a dorsal crest (not known from the fossil record) and is twice as large and the largest specimen ever found (Jurassic World, 2015)

 

Cover photo: Glyptodon carapace detail prior to repainting from the Joe Webb Peoples Museum collection at Wesleyan University. Photo courtesy of Andy Tan ’21.

Restoration: Terror of the Oceans

Wesleyan’s remarkable series of fossils casts includes two large specimens of ferocious predatorial reptiles- Plesiosaurus and IchthyosaurusThe fossil casts were in a dishearteningly deplorable state when they were rediscovered, crated in the Penthouse of Exley. The casts were put in crates when the Wesleyan Museum closed in 1957. We did not know where they were stored, but they were moved to the penthouse of the Exley Science center when the building was occupied in 1970. After 60 years of chill and thaw in the uncontrolled environment, large cracks were running across the surfaces, and the paint was chipped in many places. The Ichthyosaurus communis cast even had a number of jarring holes in various places. We probed the possibilities of salvaging these treasures, conducting extensive research into reversible restorative methods.

Being part of the Ward Series of Fossil Casts, this series of early large casts were once celebrated feature exhibits in major museums worldwide from 1866 onwards. Orange Judd donated a full series of these casts to the Wesleyan Museum when it opened in Judd Hall in 1870. The Plesiosaurus macrocephalus was an early cast of the holotype specimen of its species, and the second of its kind to be found. After almost 150 years since their making, the plaster has shrunk from off-gassing and evaporation, causing the inflexible paint layer to peel off and crackle, and simply “floating” above the plaster instead of adhering to it.

As with all the other fossils casts that are out of storage for the first time since 1957, this Plesiosaurus dolichodeirus Ward cast bears the unflattering signs of age- cracked plaster, peeling paint, unidentified stains and a thick coating of 60 year-old dust. (Photo courtesy of Andy Tan ’21)

Given their historical significance, great care was taken to employ the least intrusive methods in their restoration. We strove to minimise the changes made to the original, retaining as much of the old paint as possible. The casts were carefully inspected for unstable paint flecks, which were glued back down using acrylic medium. An airgun was passed gently over the casts to remove dust without abrading the fragile paint layer.

Each speck of missing paint is matched by mixing an identical colour with its adjacent regions from artist acrylics. The paints are then painstakingly stippled onto the plaster. (Photo courtesy of Andy Tan ’21)

A non-shrinking putty was used to fill in the larger holes and cracks in the plaster, some of which were created by early curators nailing labels into the cast itself. The missing paint chips were carefully colour-matched using archival acrylic paints, and filled in using meticulous stippling brushstrokes- a long painstaking process. Artist sponges are used to fill in parts of the background with major blemishes to recreate the natural texture of the casts. As the acrylic paints dry to a finish that looks glossier than the original, distressing of the surrounding matrix was done using fine grit sandpaper buffers, aiming for an earthy texture that is faithful to the original. Each cast took about 20 hours to restore to their formal glory. After applying a thin coat of archival breathable sealant, the casts are ready for show.

Ichthyosaurus platyodon Ward Cast in all its splendour after 30 hours of careful cleaning and restoration. (Photo courtesy of Andy Tan ’21)

Perhaps the modest, undemonstrative splendour of even the most major museums are so ingrained in our minds that we often don’t realise the strenuous effort put into each piece in an exhibition. Perhaps next time, you will take a moment to wonder as you wander, down the galleries of deep time past.

 

Cover photo: Freshly restored Ichthyosaurus communis cast detail from the Joe Webb Peoples Museum collection at Wesleyan. Photo courtesy of Andy Tan ’21.

 

 

 

Hidden Figures

Long thought to be marine dinosaurs,  Plesiosaurs and Ichthyosaurs were once formidable apex predators in the Mesozoic. Living in oceans at the same time when the dinosaurs were roaming the land, these magnificent beasts are now iconic displays in many major museums, showing these animals as representatives of this golden age of the giants, some 228 to 112 million years ago (Ma). Their discovery is a story about an unsung woman of science, whose contribution to palaeontology changed our understanding of evolution forever.

It is a story of heartbreak as well as classist and elitist struggle, which lies behind that innocent, lighthearted children tongue-twister derived from Terry Sullivan’s lyrics to a 1908 song.

She sells seashells on the seashore
The shells she sells are seashells, I’m sure
So if she sells seashells on the seashore
Then I’m sure she sells seashore shells.

The she was Mary Anning (1799-1847),  born poor in southern England, and was never far from the austerity that she internalised as a way of living. Being a woman in the household of a low-class cabinetmaker, Mary had no access to formal education. She did, however, accompany her father in the unusual pastime of fossil hunting along the coast of Lyme Regis, and their fossil finds were sold as curiosities. Neither of her father’s occupations improved the circumstances of the family, and when the father died in 1810, his pregnant wife was left with little more than a large debt.

Mary Anning with her fossil-collecting tools, accompanied by Tray, her dog, on the coast of Lyme-Regis (UK).

It was Mary who found her way in the world by continuing her father’s work in fossil hunting and turning it into a livelihood.With her widowed mother, she managed a little fossil shop  by the sea to eke out a meagre income. In 1811, she made one of the most significant fossil finds in all of history. On the coast of Lyme-Regis, she co-discovered an Ichthyosaurus with her brother – the first of its kind ever to be discovered. This gargantuan specimen was soon purchased by a private collector for £23 (approx. $2200 in today’s worth). In subsequent years, she became the most prolific fossil hunter of her time,  unearthing many other important fossils including Plesiosaurs, Pterodactyls and more Ichthyosaurs, many of which eventually became important holotype specimens.

Mary Anning’s original sketch and notes on a specimen now known as Plesiosaurus dolichodeirus. In spite of her lack of a formal education, Mary taught herself to become proficient in geology, palaeontology and fossil sketching.

Nevertheless, being a working class woman in the 19th-century, Mary never had much credibility in the scientific community. Despite her frequent correspondence with many of its prominent members, and despite providing fossils for their research, she was always the daughter of a cabinetmaker that had no place in scientific discourse. A series of 6 papers starting in 1814 by Sir Everard Home described the Ichthyosaurs based on Mary’s finds, but she was not credited in  the papers. Similarly, in 1821 and 1824, William Conybeare published and presented descriptions of the Plesiosaur fossils and thanked the collector of the fossil, but failed to mention Mary in any way. Even Sir Richard Owen- the scientist who coined the term “dinosaurs”- neglected to mention this lower class woman, despite having thanked the gentleman who acquired it from her, when he described  Plesiosaurus macrocephalus in 1840. So harshly unjust was their negligence of her contributions that she once lamented in a letter “The world has used me so unkindly, I fear it has made me suspicious of everyone.”

Wesleyan’s very own 1970 Ward cast of the Plesiosaurus macrocephalus holotype. From the collection of the Earl of Enniskillen, the original now resides in the British Museum. (Photo courtesy of Andy Tan ’21)

The Plesiosaurs and Ichthyosaurs she introduced to science were the most terrorising predators in the oceans during their heyday. Growing to 15-20m in length and weighing almost a tonne, these monsters were powered by strong flippers that allowed them to pursue their prey at remarkable speeds. Ichthyosaurs were so successful in their survival strategies that they survived for almost 120 million years. By the Cretaceous era, they had adapted to living in every ocean on the planet. Their discovery marked one of the most pivotal moments in palaeontology at a time when the issue of extinction – whether God’s divine creations could possibly become extinct – was a matter of great contention, their discovery was the final testimony that extinctions do occur. When living counterparts of tiny fossil seashells and trilobites may be argued to still be lurking somewhere in the unexplored depths of the ocean, some unfortunate fishermen would almost inevitably have encountered giant swimming lizards should they still inhabit our oceans.

Artist representation of a hunting Plesiosaur- a ferocious predator of the Mesozoic seas.

With contemporaries like Darwin, Charles Lyell and Richard Owen, Mary’s story may have been drowned in the many unjust traditions of scientific publications in the 19th century. Nevertheless, the drama that evolves around her life’s work will live on on Wesleyan’s walls and that of many major museums, as a testimony of science as a field where success in expanding knowledge triumphs over other qualities.

Marvel at the grandeur of these impressive monsters, and listen to their bittersweet tales of toil and tears of an unforgotten giant– Mary Anning. Soon to come, on the 3rd floor of Exley…

 

Cover photo: Ichthyosaurus platyodon skull detail, copy of an original found by Mary Anning,  in the Joe Webb Peoples Museum Collection at Wesleyan University. Photo courtesy of Andy Tan ’21.

Curves: Florida Pliocene Snails

Four millions years is a blink of an eye in terms of evolutionary time.

Our collection houses 5600 specimens of fossil seashells from Sarasota County, Florida, from over 460 species. These fossils are found not along the coast of Florida as one might expect, but buried in sediments far inland. After 4 million years since their demise, their diversity and density still closely resemble that of the rich marine fauna which we see at Florida’s beautiful coasts today.

Florida boasts some of the most prolific shelling beaches, arguably in the entire world. It is home to some of the largest, most exquisite living snails (gastropods), whose shells are highly sought after by avid collectors of nature’s jewels. But among the most prized of all treasures are shells that are  anomalous in their form. Seashells are categorised into two categories based on their body plans: bivalves such as clams, that have two symmetrical shells (left and right), and gastropods, such as snails, which have one shell, commonly   a whorled spire, sometimes a shallow cone. You might not have noticed a rather unusual fact about the coiled snails: almost all  are right-handed, i.e.,  their opening (aperture), where the living fleshy part of the snail emerges from its shell, is on the right when the shell placed in standard position, with the earliest-formed part (the protoconch) pointing up.

Marine snails in standard  position- their protoconches are pointing upwards and their apertures are facing the viewer. Note that the apertures are all on the right side. From left to right: Conus cedonulli, Eustrombus gigas, Murex pecten, Charonia tritonis, Busycon candelabrum.

As said above, the present beaches are not the only place in Florida where one can find shells. Far in-land, in the county of Sarasota, fossil-bearing sediments from the Pliocene contain some of the most abundant and diverse mollusc faunas in the world. Four million years ago, sea levels were much higher than  today. The entire county of Sarasota was covered by a shallow sea teeming with life. Temperature drops in the Pleistocene period, that followed the Pliocene, resulted in more of the ocean waters to be locked up at the poles in the polar ice sheets, and the sea levels fell as a consequence. Over a very short period of time, many shallow seas thus  emerged as land, forming a major part of what we know as Florida today. Marine life died in massive numbers in the inland areas and their harder parts were preserved as fossils—windows into marine diversity of the Pliocene.

In Wesleyan’s collections, even very small specimens are well preserved. Many of these are represented in large numbers (hundreds in some samples) and are kept in glass vials.

Since the Pliocene, marine faunas have adopted their modern configurations. If you walk down the shores in Florida today, you will find very similar shells as those that lived at Sarasota  four million years ago. Some species may have gone extinct, but many speciations occur in continuum with the living shells we have today.  A handful of species might no longer be represented, but many iconic species have changed very little in the millennia since. One enchanting specimen is the lightning whelk, Busycon contrarium Conrad. While most species of snails have a rightward spire, as described above, the lightning whelk and their allies have a sinistral morphology – a leftward spire. This is unique to six whelk species that are endemic to North America (and hence the species name contrarium – the contrary whelk).

Sinistral marine snails of the genus Busycon (whelk) are common in North America since  the Pliocene, and their morphologies have remained superficially similar. The Busycon contrarium on the left lived in the warm Pliocene reefs, whereas Sinistrofulgur perversum (formerly Busycon perversum) is an extant species.

It is not often clear why North American marine snails that evolved sinistrality became so successful in their native habitats. There is some evidence for an evolutionary advantage due to predator evasion; predators are used to attacking snails from their right. Alternatively, this novelty could simply be a random trait that raised from a chance mutation that happens to be selectively neutral—it renders neither advantage nor disadvantage to the snails that carry it. The success of the sinistral snails into the modern days debunks a blatant misconception many hold towards evolutionary theory. In the 18th century, evolution was given the connotation of ‘progress’, a highly goal-driven process in which all things become increasingly more complex and more sophisticated. A model of thought called the Great Chain of Being, having its origin in writings by ancient Greek neoplatonists, was prevalent from medieval times through the 18th century: all animals evolve in a mono-directional upward hierarchy that resembles a ladder with the ultimate goal being apotheosis into humans. Vestigial traditions of this school of thought are still embedded in our society, given its popularity in 18th century Christian interpretive traditions. Even today, the icon of the March of Progress that portrays humanity as the result of a linear progress from apes, is influencing the popular ideas  about evolution as a linear advancement and improvement.

A simplified version of the March of Progress, depicting evolution as synonymous to progress. In truth, evolution is more akin to an experiment that creates many potentially viable products, with a large number of failures.

In gastropods, lefties are not common, even among shells. All of the six known extant sinistral shell species of Busycon whelks in North America  diverged from one lineage – the original B. contrarium. Traits that confer significant fitness often have high levels of convergence in analogous habitats. Given that sinistrality in these North American gastropods only evolved once in the marine environment, the evolutionary advantage of this trait is not clear, and it might be negligible.  In our collection, we are fortunate to feature another sinistral species- Conus adversarius. These unusual species are in high demand by collectors seeking novelties.

As these popular jewels of the natural world still line our shores today, measures are in place to protect their heritage that spanned more than 4 million years of geological time. Legislation in Florida aims to restrict the removal of living shells from their natural habitat, and  to preserve these ancient lineages which originated before the dawn of humans, lest our arrogance and ignorance cause them to disappear from our shores forever.

The origin of Wesleyan’s large collection of Pliocene molluscs from Sarasota, Florida is still undetermined. Some detective work in the archives will be done to track down the provenance of these beautiful specimens.

 

Coauthored by Tan Yu Kai and Andy Tan

Cover photo: Apical view of a Busycon contrarium in the Joe Webb Peoples Museum Collection at Wesleyan University. Photo courtesy of Andy Tan ’21.