Tuesday, 7 April 2020

TRENT RIVER PALAEONTOLOGY

Trent River, Photo: Betty Franklin
Dan Bowen, Chair of the Vancouver Island Palaeontological Society has led many fossil field trips along the Trent River. The photo you see here was taken by the deeply awesome Betty Franklin on one of those trips.

The rocks that make up this riverbed today were laid down south of the equator as small, tropical islands. They rode across the Pacific heading north and slightly east over the past 80 million years to where we find them today.

The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. And it is massive. At 103 million km2 (40 million sq mi), it is the largest tectonic plate and continues to grow fed by volcanic eruptions that piggyback onto its trailing edge.

This relentless expansion pushes the Pacific Plate into the North American Plate. The pressure subducts it beneath our continent where it then melts back into the earth. Plate tectonics are slow but powerful forces. The island chains that rode the plates across the Pacific smashed into our coastline and slowly built the province of British Columbia. And because each of those islands had a different origin, they create pockets of interesting and diverse geology.

It is these islands that make up the Insular Belt — a physio-geological region on the northwestern North American coast. It consists of three major island groups — and many smaller islands — that stretches from southern British Columbia up into Alaska and the Yukon. These bits of islands on the move arrived from the Late Cretaceous through the Eocene — and continues to this day.

The rocks that form the Insular Superterrane are allochthonous, meaning they are not related to the rest of the North American continent. The rocks we walk over along the Trent River are distinct from those we find throughout the rest of Vancouver Island, Haida Gwaii, the rest of the province of British Columbia and completely foreign to those we find next door in Alberta.

To discover what we do find on the Trent takes only a wee stroll, a bit of digging and time to put all the pieces of the puzzle together. The first geological forays to Vancouver Island were to look for coal deposits, the profitable remains of ancient forests that could be burned to power industry.
Jim Monger and Charlie Ross of the Geological Survey of Canada furthered that work by looking at the complex geology of the Comox Basin in the 1970s. It was their work that helped tease out how and where the rocks we see along the Trent today were formed and made their way north.

We know from their work that by 80 million years ago, the Insular Superterrane had made its way to what is now British Columbia. The lands were forested much as they are now but by extinct genera and families. The fossil remains of trees similar to oak, poplar, maple and ash can be found along the Trent and Vancouver Island. We also see the lovely remains of flowering plants such as Cupanities crenularis, figs and breadfruit.

Heading up the river, you come to a delineation zone that clearly marks the contact between the dark grey marine shales and mudstones of the Haslam Formation where they meet the sandstones of the Comox Formation. Fossil material is less abundant in the Comox sandstones, Here you begin to see fossilized wood and identifiable fossil plant material.

Further upstream, there is a small tributary, Idle Creek, where you can find more of this terrestrial material in the sandy shales. As you walk up, you see identifiable fossil plants beneath your feet and jungle-like, overgrown snarly trees all around you.

Polyptychoceras vancouverense / BCPA 2003
Walking west from the Trent River Falls at the bottom, you pass the infamous Ammonite Alley, where you can find Mesopuzosia sp. and Kitchinites sp. of the Upper Cretaceous (Santonian), Haslam Formation. Here we see the Polytychoceras vancouverense zone. Continuing west, we reach the Fossil Turtle Site then the Inland Island Highway.

The Trent River has yielded some very interesting marine specimens, and significant terrestrial finds. We've found both a wonderful terrestrial helochelydrid turtle, Naomichelys speciosa, and the caudal vertebrae of a Hadrosauroid dinosaur. Walking down from the Hadrosaur site we come to the site of a fossil ratfish find. A little further again and we reach the Polyptychoceras zone and then come to the contact of the two formations. The rocks here have traveled a long way to their current location. With them, we peel away the layers of geologic history of both the Comox Valley and the province of British Columbia.

Photo One: Trent River, Haslam Formation, Trent River. Betty Franklin. Photo Two: Polyptychoceras vancouverense from the Upper Cretaceous (Santonian), Haslam formation, Trent River, Vancouver Island, British Columbia, Canada. 2003 BCPA Calendar.

References: Note on the occurrence of the marine turtle Desmatochelys (Reptilia: Chelonioidea) from the Upper Cretaceous of Vancouver Island Elizabeth L. Nicholls Canadian Journal of Earth Sciences (1992) 29 (2): 377–380. https://doi.org/10.1139/e92-033

Monday, 6 April 2020

NAOMICHELYS SPECIOSA OF THE HASLAM

Naomichelys speciosa, a new Helochelydrid turtle from the Trent River
Helochelydrids are a group of poorly known turtles from Late Jurassic to Late Cretaceous deposits in North America and Europe.

Naomichelys is known numerous remains from western North America, most notably the holotype partial shell from the Cloverly Formation of Montana and a complete skeleton from the Antlers Formation of Texas. It is the only known North American member of Helochelydridae.

Naomichelys is a member of the family Helochelydridae. We find their fossilized remains in Late Jurassic to Late Cretaceous deposits in North America and Europe. Within North America, only the species Naomichelys speciosa is known from relatively complete material which makes comparisons between specimens from other localities challenging.

Phil Currie along with co-authors Matthew J. Vavrek, Derek W. Larson, Donald B. Brinkman and Joe Morin described a new species of Helochelydrid terrestrial turtle found on the Trent River.

The new genus and species of helochelydrid turtle was based on a relatively complete shell from the marine Haslam Formation (Santonian) of Vancouver Island, British Columbia, Canada.

The new species is characterized by several distinctive shell features, notably a forward curving process on the anterior portion of the hyoplastra, strongly distinguishing it from N. speciosa. The shell is relatively small but does appear to be from a fully grown individual, suggesting that the species was generally much smaller than other known helochelydrids.

Previously most records of helochelydrids in North America had been assigned to N. speciosa, regardless of actual diagnosable characters. The presence of an additional species of helochelydrid from North America indicates that a greater diversity of the taxon was present than was previously recognized. While the interspecific relationships of helochelydrids remain difficult to fully assess, due to the lack of well-preserved specimens, this new species provides additional geographic and phylogenetic data that aids our understanding of this enigmatic group.

Sunday, 5 April 2020

MIGHTY DOVE CREEK MOSASAUR

Dove Creek Mosasaur (Tylosaur) found by Rick Ross, VIPS
This specimen of the teeth and lower jawbone of a large marine reptile was discovered by Rick Ross, Vancouver Island Palaeontological Society, during the construction of the Inland Highway, near the Dove Creek intersection on Vancouver Island.

If you look closely, you can see several smaller disc-shaped objects to the upper right. These are part of this fellow's sclerotic eye-ring.
These bony plates allowed for safe hunting in deeper waters as the structures protected the delicate eye tissue from the intense water pressure. Diving birds have these same bony plates.

Mosasaurs had a hinged jaw that allowed them to swallow prey larger than themselves. They evolved special pterogoid teeth projecting backwards into the roof of their mouths that acted as guards against escaping prey. The jaw bones Rick found were exposed just up to the hinge. Given the size, this toothy fellow could have been as much as seven (7) metres long and weighed up to a tonne.

Along with the significant find of the mosasaur, Rick Ross collected many ammonites and other marine invetebrates exposed during the construction of the Inland Island Highway. He donated the majority of them to the Royal BC Museum in Victoria. They now adorn a cabinet bearing his name and are tucked lovingly in with stories he wrote about his collecting adventures.

Urakawites heteromorph found by Rick Ross, VIPS
Science owes a great debt to the keen eye and fast thinking of Rick Ross for his work in recovering the specimen. Rick was out on a Sunday looking through the blocks that destined to be crushed to finish up the tail end of the new highway construction. The crews had just dropped a pile of massive blocks near the Dove Creek Road crossing.

Each of the blocks was one to five tonnes in size. Rick was looking through them when he spotted a concretion sticking out. It didn't look all that different from the hundreds he had been found up and down the highway. Interested to see what it might contain, Rick took his geology hammer and struck a blow. Off popped the end and inside was a large perfect mosasaur tooth.

Looking closer, he could see bone sticking out in several other places within this massive block. Excited for the find and not quite sure how to approach excavating it from an active construction site, Rick searched the highway and finally located a maintenance working greasing up some heavy machinery. Rick excitedly told the field mechanic about the find and inquired who would need to be called to save the block. His answer was disappointing. The block was destined to be bulldozed in the morning. Panicked but still hopeful, Rick asked who his supervisor was and how to reach him on a Sunday. While initially hesitant, the urgency and excitement in Rick's voice swayed him. With a warning that the supervisor would likely not be impressed to get his call, he relented and shared the telephone number. Rick dialed the number and received the predicted reaction. Unrelenting, Rick swayed the supervisor who agreed that if Rick could get a truck up to the site first thing in the AM, the block could be lifted onto the truck. The next hour was filled with phone calls and putting together a plan to get the mighty block.

Rick called Pat Trask from the Courtenay Museum. The two are fossil hunting buddies and Rick was sure that Pat would be up for the challenge. The next call was to Doug Embree, another fossil hunting buddy from the Comox Valley. As luck would have it, Doug's brother Sam had a two-tonne flatbed truck that they would be able to use. The struggle now was would it take the weight? Monday morning arrived and the block was lifted onto the flatbed with the aid of a drill hole and chain through one corner.

The truck groaned and leaned heavily all the way into town. They had to come in via the 17th Street Bridge as a safe route to the Courtenay Museum. the local building store lent the use of a large forklift to lift the block from the heavily tilted truckbed down onto the back deck of the museum. Once in place, it was far too big to move. It sat there for almost seven years before finally being shipped to a preparatory lab down in Washington. There it was prepped and whittled down to the still massive block we see today.

This specimen is now housed in the Courtenay and District Museum on Vancouver Island, British Columbia. The jaw and assocated bones are tagged as a mosasaur, but exactly what kind will need more study. We may be looking at a Tylosaurus, a very large mosasaur with an elongated, cylindrical premaxilla (snout) from which it takes its name. These were the big boys of our ancient seas who snacked on plesiosaurs and other smaller marine reptiles.

T. proriger specimen found with a plesiosaur in its stomach
In 1918, Charles H. Sternberg found a Tylosaurus, with the remains of a plesiosaur in its stomach while collecting in the Smoky Hill Chalk of Logan County, Kansas. You can visit the specimen at the Smithsonian.

Like many other mosasaurs, the early history of this taxon is complex and involves the infamous rivalry between two early American paleontologists, Edward Drinker Cope and Othniel Charles Marsh. Cope wins the day in terms of longevity in his naming of these mighty beasts.

Though many species of Tylosaurus have been named over the years, only a few are now recognized by scientists as taxonomically valid. They are: Tylosaurus proriger (Cope, 1869), from the Santonian and lower to middle Campanian of North America (Kansas, Alabama, Nebraska) and Tylosaurus nepaeolicus (Cope, 1874), from the Santonian of North America (Kansas). Tylosaurus kansasensis, named by Everhart in 2005 from the late Coniacian of Kansas, has been shown to be based on juvenile specimens of T. nepaeolicus.

It is likely that T. proriger evolved as a paedomorphic variety of T. nepaeolicus, retaining juvenile features into adulthood while attaining a much larger adult size.

Along with plesiosaurs, sharks, fish, and other mosasaurs, Tylosaurus was a dominant predator of the Western Interior Seaway during the Late Cretaceous. The genus was among the largest of the mosasaurs — along with Mosasaurus hoffmannii — with the possibly conspecific Hainosaurus bernardi reaching lengths up to 12.2 meters (40 ft), and T. pembinensis reaching comparable sizes. T. proriger, the largest species of Tylosaurus, reached a whopping 14 m (46 ft). While the Dove Creek Mosasaur was half that size, it may be one of T. proriger's smaller cousins.

Photo One: Dove Creek Mosasaur by Heidi Henderson. Courtenay Museum Collection.
Photo Two: Urakawites heteromorph ammonite by Rick Ross. RBCM Collection
Photo Three: T. proriger specimen which was found with a plesiosaur in its stomach. By Ryan Somma - Flickr, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=9004614

Saturday, 4 April 2020

ALBERTONECTES OF THE WESTERN INTERIOR SEAWAY

Albertonectes vanderveldei
During the Cretaceous, the Western Interior Seaway split North America into two landmasses. Part of the seaway was the Bearpaw Sea, a warm, shallow body of water that covered 1.7 million square kilometres of the coastal plain about 74 million years ago.

Today, the Bearpaw Formation, also called the Bearpaw Shale, is a geologic formation of Late Cretaceous (Campanian) age. It outcrops in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, and was named for the Bear Paw Mountains in Montana. It includes a wide range of marine fossils, as well as the remains of a few dinosaurs. It is known for its fossil ammonites, some of which are mined in Alberta to produce the organic gemstone ammolite.

It was home to many marine reptiles, ammonites, fishes, and other aquatic life. Elasmosaurs —long-necked plesiosaurs — were one group of marine reptiles that inhabited our ancient oceans.

They were primarily fish eaters, and used their long necks to strike at fish, then trapped them in their interlocking teeth. A new genus and species of elasmosaur, Albertonectes vanderveldei, was uncovered in 2007 during routine ammonite shell mining.

Albertonectes has 76 neck vertebrae, the most of any animal known — compare this to giraffes that only have seven neck vertebrae. Albertonectes had a neck that was 6.5 metres long. Was it flexible and able to bend sharply and quickly? Or was it stiff, with a gentle arc that could cover a large area? Paleontologists used computer modelling to study the neck’s flexibility. The neck broke into four segments when it collapsed on the seafloor.

This incredible specimen provides insight into what marine communities were like during the Cretaceous Period. The fossilized remains of other animals that lived alongside Albertonectes are found in the rocks formed at the bottom of the Bearpaw Sea. These included potential prey such as small fishes, ammonites, and crayfish. From recovered shark teeth, and tooth marks left on the bone, palaeontologists determined that the carcass of Albertonectes. was scavenged by one or more sharks.

More on this impressive find:
https://royaltyrrellmuseum.wpcomstaging.com/./albertonecte…/

Photo: Roland Tanglao from Vancouver, Canada - 5d-dinosaur-camp-day2-20120802-64.jpgUploaded by FunkMonk, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=20902049

Friday, 3 April 2020

UPPER CRETACEOUS FAUNA OF THE PACIFIC

The Pacific fauna from the Upper Haslam Formation was cut-off geographically from their contemporaries living in the waters of the Western Interior Seaway.

That Seaway — also called the Cretaceous Seaway, the Niobrara Sea, the North American Inland Sea, and the Western Interior Sea  — was the large inland sea that formed during the mid- to late Cretaceous and again during the very early Paleogene. It split the continent of North America into two landmasses, Laramidia to the west and Appalachia to the east.

We see evidence of this isolation when we look at the fossil marine reptiles from the Late Cretaceous Nanaimo Group of Vancouver Island.

The Late Cretaceous Western Interior Seaway of North America has an abundant and well-studied record of fossil marine reptiles. The Pacific faunas we find on Vancouver Island were isolated from their contemporaneous faunas in the Western Interior Seaway. The ancient sea stretched from the Gulf of Mexico and through the middle of the modern-day countries of the United States and Canada, meeting with the Arctic Ocean to the north. At its largest, it was 2,500 feet (760 m) deep, 600 miles (970 km) wide and over 2,000 miles (3,200 km) long.

Betsy Nicholls and Dirk Meckert published on the marine reptiles from the Nanaimo Group (Upper Cretaceous) of Vancouver Island in the Canadian Journal of Earth Sciences in 2002.

They were comparing the newly discovered fossil from the Haslam and Pender formations (upper Santonian) near Courtenay, British Columbia, which include elasmosaurid plesiosaurs, turtles, and mosasaurs. These finds are only the second fauna of Late Cretaceous marine reptiles known from the Pacific Coast, the other being the fossiliferous shales from the Chico Group, Moreno Formation of California (Maastrichtian) that overlies the Panoche Formation.

The new Nanaimo Group fossils are some 15 million years older than those from the Moreno Formation. Similarly to the California fauna, there are no polycotylid plesiosaurs but the Nanaimo Group fauna does include a new genus of mosasaur. The species that we find on Vancouver Island lived at the same time but were not mixing geographically. What we see in our faunal mix reinforces the provinciality of the Pacific faunas and their isolation from contemporaneous faunas in the Western Interior Seaway.

Elizabeth L Nicholls and Dirk Meckert; Marine reptiles from the Nanaimo Group (Upper Cretaceous) of Vancouver Island; Canadian Journal of Earth Sciences, 2002, 39(11): 1591-1603, https://doi.org/10.1139/e02-075

Thursday, 2 April 2020

KOURISODON PUNTLEDGENSIS

Kourisodon Puntledgensis
Mosasaurs were large, globally distributed marine predators who dominated our Late Cretaceous oceans. Since the unearthing of the first mosasaur in 1766 (Mulder, 2003) we've discovered their fossil remains most everywhere around the globe — New Zealand, Antarctica, Africa, North and South America, Europe and Japan.

Since the first find of a marine reptile on the Puntledge River, members of the Vancouver Island Palaeontological Society have made many significant paleontological finds.

We've now found the fossil remains of an elasmosaur and two mosasaurs along the banks of the Puntledge River, says Dan Bowen, Chair of the Vancouver Island Palaeontological Society.

The first set of about 10 mosasaurs vertebrae (Platecarpus) was found by Tim O’Bear and unearthed by a team of VIPS and Museum enthusiasts led by Dr. Rolf Ludvigsen. Dan Bowen and Joe Morin of the VIPS prepped these specimens for the Museum.

In 1993, a new species of mosasaur, Kourisodon puntledgensis, a razor-toothed mosasaur, was found upstream from the elasmosaur site by Joe Zembiliwich on a field trip led by Mike Trask. A replica of this specimen now calls The Canadian Fossil Discovery Centre in Morden home.

What is significant about this specimen is that it is a new genus and species. At 4.5 meters, it is a bit smaller than most mosasaurs and similar to Clidastes, but just as mighty.

Kourisodon ("razor tooth") is an extinct genus of mosasaur. Fossils have been found from Vancouver Island in British Columbia, Canada, as well as from the Izumi Group of Japan.

These finds date back to the late Santonian stage and the late Campanian to the late Maastrichtian, respectively, of the Late Cretaceous. Kourisodon was originally described as a member of the Leiodontini, more recently as a Clidastine.

Interestingly, this species has been found in this one locality in Canada and across the Pacific in the basal part of the Upper Cretaceous — middle Campanian to Maastrichtian — of the Izumi Group, Izumi Mountains and Awaji Island of southwestern Japan. We see an interesting correlation with the ammonite fauna from these two regions as well.

In 2005, a fragmentary skeleton from exposures of the Izumi Group on Shikoku Island, Japan, was assigned to Kourisodon sp.

The Japanese specimen had longer maxillary teeth along with a few other differences from K. puntledgensis, which the authors interpreted to mean that this individual belonged to a second species, although this new species has not yet been formally named. Other fragmentary remains from the Izumi Group have been tentatively assigned to K. sp., some of which represent juvenile animals.

Until recently, mosasaur remains from the Izumi Group (Upper Cretaceous) in southwest Japan comprised only scattered finds. Recently, additional fossil material has been unearthed from the upper Campanian Hiketa Formation in Kagawa Prefecture.

A new Kourisodon sp. has just been recorded, on the basis of portions of skull and mandible which has small and laterally compressed teeth. A few teeth of the same or similar type have previously been described from the Maastrichtian Mutsuo Formation in Osaka Prefecture. A report of Mosasaurus sp. A, which resembles M. missouriensis and M. dekayi, is based on some cranial and mandible remains, inclusive of numerous teeth and a few well-preserved cervical and two incomplete dorsal vertebrae, from the Maastrichtian Mutsuo Formation in Osaka Prefecture.

There's still a bit of sorting to do to tease out the lineage of these lovely marine reptiles. A slender tooth of Mosasaurus sp. from the Mutsuo Formation has since been reassigned to Platecarpus (Plioplatecarpinae) yet may indeed be a species of Mosasaurus. It is currently recorded as Mosasaurus sp. B. Many smaller specimens of mosasaurids have been found in the Izumi Group. It may have been that these are juvenile mosasaurs or smaller-sized, Kourisodon-like animals. Recent finds of Kourisodon sp. from the upper Campanian Hiketa Formation and the Maastrichtian Mutsuo Formation suggests that we are seeing Kourisodon-like animals and a strong correlation with our own Pacific fauna from the Nanaimo Group.

What we do not see is a correlation between our Pacific fauna and those from our neighbouring province to the east. Betsy Nicholls and Dirk Meckert published on the marine reptiles from the Nanaimo Group (Upper Cretaceous) of Vancouver Island in the Canadian Journal of Earth Sciences in 2002. What we see in our faunal mix reinforces the provinciality of the Pacific faunas — though a  strong correlation with Cretaceous Japanese fauna — and their isolation from contemporaneous faunas in the Western Interior Seaway.

Wednesday, 1 April 2020

COURTENAY HADROSAUROID FROM THE TRENT RIVER

Hadrosaurus, also known as "duck-billed" dinosaurs, were a very successful group of plant-eaters that thrived throughout western Canada during the late Cretaceous, some 70 to 84 million years ago.

Hadrosaurs lived as part of a herd, dining on pine needles, horsetails, twigs and flowering plants.

Hadrosaurs are ornithischians — an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. They are close relatives and possibly descendants of the earlier iguanodontid dinosaurs. They had slightly webbed, camel-like feet with pads on the bottom for cushioning and perhaps a bit of extra propulsion in water. They were primarily terrestrial but did enjoy feeding on plants near and in shallow water. There had a sturdy build with a stiff tail and robust bone structure. 

At their emergence in the fossil record, they were quite small, roughly three meters long. That's slightly smaller than an American bison. They evolved during the Cretaceous with some of their lineage reaching up to 20 meters or 65 feet.

Hadrosaurs are very rare in British Columbia but a common fossil in our provincial neighbour, Alberta, to the east. Here, along with the rest of the world, they were more abundant than sauropods and a relatively common fossil find. They were common in the Upper Cretaceous of Europe, Asia, and North America.

There are two main groups of Hadrosaurs, crested and non-crested. The bony crest on the top of the head of the hadrosaurs was hollow and attached to the nasal passages. It is thought that the hollow crest was used to make different sounds. These sounds may have signalled distress or been the hadrosaur equivalent of a wolf whistle used to attract mates. Given their size it would have made for quite the trumpeting sound.

This beautiful specimen graces the back galleries of the Courtenay and District Museum on Vancouver Island, British Columbia, Canada. I was very fortunate to have a tour this past summer with the deeply awesome Mike Trask joined by the lovely Lori Vesper. The museum houses an extensive collection of palaeontological and archaeological material found on Vancouver Island, many of which have been donated by the Vancouver Island Palaeontological Society.

Dan Bowen, Chair of the Vancouver Island Palaeontological Society, shared the photo you see here of the first partly articulated dinosaur from Vancouver Island ever found. The vertebrate photo and illustration are from a presentation by Dr. David Evans at the 2018 Paleontological Symposium in Courtenay.  The research efforts of the VIPS run deep in British Columbia and this new very significant find is no exception. A Hadrosauroid dinosaur is a rare occurrence and further evidence of the terrestrial influence in the Upper Cretaceous, Nanaimo Group, Vancouver Island — outcrops that we traditionally thought of as marine from years of collecting well-preserved marine fossil fauna.

CDM 002 / Hadrosauroid Caudal Vertebrae
This fossil bone material was found years ago by Mike Trask of the Vancouver Island Palaeontological Society. You may recall that he was the same fellow who found the Courtenay Elasmosaur on the Puntledge River.

Mike was leading a fossil expedition on the Trent River. While searching through the Upper Cretaceous shales, the group found an articulated mass of bones that looked quite promising.

Given the history of the finds in the area, the bones were thought to be from a marine reptile.

Since that time, we've found a wonderful terrestrial helochelydrid turtle, Naomichelys speciosa, but up to this point, the Trent had been known for its fossil marine fauna, not terrestrial. Efforts were made to excavate more of the specimen, and in all more than 25 associated vertebrae were collected with the help of some 40+ volunteers. Some of these were put on display in the Courtenay Museum and mislabeled for years as an unidentified plesiosaur.

In 2016, after years collecting dust and praise in equal measure, the bones were reexamined. They didn't quite match what we'd expect from a marine reptile. Once fully prepped, and seemingly unlikely, they turned out to be from a terrestrial hadrosauroid. Dr. David Evans, Temerty Chair in Vertebrate Palaeontology, Department of Natural History, Palaeobiology from the Royal Ontario Museum, confirmed the ID and began working on the partial duck-billed dinosaur skeleton to publish on the find.

Drawing of Trent River Hadrosauroid  Caudal Vertebrae
Now fully prepped, the details of this articulated Hadrosauriod caudal vertebrae come to light. We can see the prominent chevron facets indicative of caudal vertebrae with it's a nice hexagonal centrum shape on anterior view.

There are well-defined long, raked neural spines that expand distally — up and away from the acoelous centrum. Between the successive vertebrae, there would likely have been a fibrocartilaginous intervertebral body with a gel-like core —  the nucleus pulposus — which is derived from the embryonic notochord. This is a handy feature in a vertebrate built as sturdily as a hadrosaur. Acoelous vertebrae have evolved to be especially well-suited to receive and distribute compressive forces within the vertebral column.

This fellow has kissing cousins over in the state of New Jersey where this species is the official state fossil. The first of his kind was found by John Estaugh Hopkins in New Jersey back in 1838. Since that time, we've found many hadrosaurs in Alberta, particularly the Edmontosuaurs, another member of the subfamily Hadrosaurine.

In 1978, Princeton University found fifteen juvenile hadrosaurs, Maiasaura ("good mother lizard") on a paleontological expedition to the Upper Cretaceous, Two Medicine Formation of Teton County in western Montana. Their initial finds of several small skeletons had them on the hunt for potential nests — and they found them complete with wee baby hatchlings!

Photo / Sketch of CDM 002: Dr. David Evans, Temerty Chair in Vertebrate Palaeontology, Department of Natural History, Palaeobiology from the Royal Ontario Museum provided by Dan Bowen, Chair, Vancouver Island Palaeontological Society. The vertebrate photo and illustration are from a presentation by Dr. David Evans at the 2018 Paleontological Symposium in Courtenay.

Tuesday, 31 March 2020

DESMATOCHELYS FROM THE PUNTLEDGE

Desmatochelys sculpture by P. Oudendag
A lovely fossil turtle, Desmatochelys cf. D. lowi (Williston, 1894) found by Richard Bolt in the shales of the Trent River Formation along the Puntledge River in the early 1990s. At the time, it was the first documented account of a Cretaceous marine vertebrate from the Pacific coast of Canada — a first which shows you how much we've learned about our Pacific coast in just the last few years.

Dr. Betsy Nicholls wrote up the paper and published in the Canadian Journal of Earth Sciences in 1992. She described the specimen from some postcranial elements and part of the mandible. Unfortunately, we were never able to recover the skull.

It was the Desmatchelys that inspired the 1999 BCPA Symposium conference logo held at UBC that year — a trilobite embedded within a turtle, celebrating recent significant contributions to Canadian palaeontology. It was also the inspiration for the sculpture you see here by Peter Odendag. I met Peter at the conference and was delighted to see his paleo inspired sculptures. Both his Desmatochelys and coelacanth now grace the displays at the Courtenay Museum on Vancouver Island.

While this was the first turtle find on Vancouver Island, the hunt for our fossilized reptilian friends goes back many years, but the hunt for Desmatochelys begins in the Bone Wars of the late 1800s. It was Samuel Wendell Williston who described the first specimen of Desmatochelys in the Kansas University Quarterly in 1895. Williston was a contemporary of C.H. Sternberg, Edward Drinker Cope and Othniel Charles Marsh. As history tells it, from 1877 to around 1892, both Cope and Marsh used their wealth and influence to finance their own expeditions and to procure the services and dinosaur bones from lesser fossil hunters. Williston was one of Marsh's boys.

Desmatochelys cf. D. lowi, Upper Cretaceous Haslam Formation 
In 1876, Williston wrote a letter to Marsh reporting that Sternberg had, "got one or two large turtles that are good and some pretty good saurians," (Shor, 1971:77) along the Smoky Hill River, upper Chalk Logan County. Williston's hunt for turtles continued and it was not long after that he would hold in his hand a new species on which he would both publish and name. The specimen had been found by a railroad worker near Fairbury, Nebraska. These were hard times and fossils were exchanged for hard currency then as they are today. The specimen was passed through the hands of one curiosity seeker after another until it eventually made its way to M. A. Low. Mister Low was more a man of science than currency and he generously donated to the University of Kansas in 1893.

That generosity was rewarded. Had the specimen not be accessioned into the collections at Kansas University by Low, it might well have been sold to Marsh and published under the name Marshanii. Instead, Williston was given the fossil to study. He published and in discovering it was a new species, chose the scientific name for the specimen. Williston tipped his hat to Low and called the new species Desmatochelys Iowi when published his finding on a well-preserved fossil turtle (KUVP 1200) from the Upper Cretaceous Benton Formation of Fairbury, Nebraska, later that year. The find included the skull, lower jaw and portions of the carapace, plastron, limbs and limb girdles. Williston described it as a new genus and species of marine turtle, Desmatochelys Iowi, and placed it in a new family, Desmatochelyidae. Since its first discovery at least five new specimens of D. lowi have been described from Cretaceous deposits in South Dakota, Kansas, Arizona, Canada, and Mexico.

In 1960, the carapace, limbs and limb girdles of a second specimen (CNHM PR 385) were found in Cretaceous sediment deposits with pre-Cambrian granites in a quarry on the South Dakota-western Minnesota border (Zangerl and Sloan, 1960). They pushed back on Williston's assertion that his new species belonged in the newly described family Desmatochelyidae, instead of recognizing it to be a primitive cheloniid within the family Cheloniidae — a family of large marine turtles characterized by their flat "hard-shells" with their streamlined, wide, rounded shapes and paddle-like forelimb flippers.

https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/cheloniidae

Monday, 30 March 2020

PUNTLEDGE ELASMOSAUR

Puntledge Elasmosaur found by Mike Trask
This lengthy beauty is an elasmosaur, a large marine reptile now housed in the Courtenay and District Museum on Vancouver Island.

This specimen was found by Mike Trask and his daughter in the winter of 1988 while fossil collecting along the Puntledge River. While he couldn't have known it at the time, it was this discovery and those that followed that would spark a renewed interest in palaeontology on Vancouver Island and the province of British Columbia.

Mike had foraged ahead, adding chalk outlines to interesting fossil and nodules in the 83 million-year-old shales along the riverbank. His daughter, Heather, was looking at the interesting features he had just outlined when they both noticed some tasty blocks and concretions in situ just a few meters away. Taking a closer look, they were thrilled to discover that they held the bones of a large marine reptile.

Unsure of what exactly they'd discovered but recognizing them as significant, Mike reached out to Dr. Betsy Nicholls at the Royal Tyrell Museum.

It was Betsy who'd written up the incomplete specimen of fossil turtle, Desmatochelys cf. D. lowi — Reptilia: Chelonioidea — found by Richard Bolt, VIPS, in the shales of the Trent River Formation along the Puntledge River in the early 1990s. Dr. Nicholls wrote up the paper and published in the Canadian Journal of Earth Sciences in 1992.

At that time, it was the first documented account of a Cretaceous marine vertebrate from the Pacific coast of Canada, which shows you how much we've learned about our Pacific coast in just the last few years.

The Desmatchelys find inspired the 1999 BCPA Symposium conference logo. Every second year, the BCPA hosts a symposium. The 1999 conference at UBC was the first time the Vancouver Paleontological Society had hosted a BCPA conference. The conference abstract was graced with a trilobite embedded within a turtle, celebrating recent significant contributions to Canadian palaeontology.

Elasmosaur skull and teeth found by Mike Trask
When Mike showed her the bones he'd found, Betsy confirmed them to be that of an elasmosaur, a large marine reptile with a small head, razor-sharp teeth and a long neck  — and the first discovery of an elasmosaur west of the Canadian Rockies — another first. It was one of those moments that lights up and inspires a whole community.

When the bones were fully excavated, this 15-meter marine beauty underwent a year of preparation to reveal the skeleton you see here. You can visit the fully prepped specimen and see the articulated bones beneath a glass case in the Courtenay Museum on Vancouver Island.

The Puntledge Elasmosaur has graced the cover of Canada's stamps and was voted as British Columbia's Provincial Fossil in 2019. This honour has the Puntledge Elasmosaur cozied up to other provincial symbols and emblems that include the Pacific Dogwood, Jade, the Steller's Jay, Western Red Cedar, Spirit Bear and Pacific Salmon. The runner-up for BC's Provincial Fossil was Shonisaurus sikanniensis, a massive 21-metre ichthyosaur found in Triassic outcrops in northern British Columbia. That beauty is a worthy reminder of what hunted in our ancient oceans some 220 million years ago.

BCPA Symposium / Heidi Henderson, Mike Trask, Adam Melzak
Since that first moment of discovery, many wonderful events transpired. In the Fall of 1991, Mike Trask was teaching a course on paleontology at the North Island College.

Two of his students were Ann and Joe Zanbilowitz. With the classroom portion of the course finished up, the group set out for a fossil expedition on the Puntledge River. Within five minutes of their search, Joe found a few small articulated vertebrae that we now know to be the type specimen of the mosasaur, Kourisodon puntledgensis. That find, along with some of the other paleontological goodies from the area, prompted the formation of the Vancouver Island Palaeontological Society from an idea to a registered society in 1992. By 1993 membership had grown from a dozen to 250.

In 1992, the Vancouver Island Palaeontological Society passed a motion to encourage the formation of a provincial umbrella group to act as an advocate to promote interaction amongst various paleontological organizations. Through the efforts of Mike Trask, Dan Bowen, Rolf Ludvigsen and others, the first meeting of the Board of Directors of the B.C. Paleontological Alliance was held in 1993.

Mike Trask hiking up at Landslide Lake, British Columbia
In 1994 the membership of the VIPS split into three regional societies, the original VIPS, the new VanPS in Vancouver, and the new VIPMS, the Vancouver island Paleontological Museum Society based in Qualicum.

In 1995, the Victoria Palaeontological Society, the VicPS, was formed. This was followed by the Tumbler Ridge Foundation (TRMF) and opening of the Dinosaur Discovery Gallery in Tumbler Ridge.

The British Columbia Paleontological Alliance and various regional societies, particularly the Vancouver Island Palaeontological Society (VIPS), continue to make significant contributions to paleontology. We've now found the fossil remains of an elasmosaur and two mosasaurs along the banks of the Puntledge River, says Dan Bowen, Chair of the Vancouver Island Palaeontological Society.

The first set of about 10 mosasaurs vertebrae (Platecarpus) was found by Tim O’Bear and unearthed by a team of VIPS and Museum enthusiasts led by Dr. Rolf Ludvigsen. Dan Bowen and Joe Morin of the VIPS later prepped these specimens for the Museum.

In 1993, just a few years later, a new species of mosasaur, Kourisodon puntledgensis, a razor-toothed mosasaur, was found upstream of the elasmosaur site by Joe Zembiliwich on a field trip led by Mike Trask. A replica of this specimen now calls The Canadian Fossil Discovery Centre in Morden home.
What is significant about this specimen is that it is a new genus and species. At 4.5 meters, it is a bit smaller than most mosasaurs and similar to Clidastes, but just as mighty.

Comox Valley Elasmosaur / Dino Stamps of Canada
Interestingly, this species has been found in this one locality in Canada and across the Pacific in the basal part of the Upper Cretaceous — middle Campanian to Maastrichtian — of the Izumi Group, Izumi Mountains and Awaji Island of southwestern Japan. We see an interesting correlation with the ammonite fauna from these two regions as well.

The Courtenay and District Museum, the community surrounding it and allied organizations like the Vancouver Island Palaeontological Society (VIPS), have a lot to be proud of. Their outreach and educational programs continue to inspire young and old alike. These discoveries led to the expansion of the local museum, the elasmosaur excavation area becoming a provincial heritage site and the impetus for many, many teaching programs since.

Oh, and Mike Trask — he continues to be deeply awesome, intuitive and exceptionally observant. The good Master Trask went on to find the first hadrosauroid in the province. While Alberta is littered with them, a Hadrosauroid dinosaur is a rare occurrence in this part of Canada and further evidence of the terrestrial influence in the Upper Cretaceous, Nanaimo Group of Vancouver Island. Perhaps one day we'll be seeing a duck-billed dinosaur from British Columbia gracing Canada's stamps. Fancy that.

References: Nicholls, E. L. and Meckert, D. (2002). Marine reptiles from the Nanaimo Group (Upper Cretaceous) of Vancouver Island. Canadian Journal of Earth Science 39(11):1591-1603.
Tanimoto, M. (2005). "Mosasaur remains from the Upper Cretaceous Izumi Group of Southwest Japan" (PDF). Netherlands Journal of Geosciences. 84: 373–378. doi:10.1017/s0016774600021156.
Ferocious new mosasaur skeleton coming to Morden | CBC News". CBC. Retrieved 2018-07-16.

Sunday, 29 March 2020

SAUROPTERYGIAN REPTILES

Libonectes atlasense / Andy Chua Collection
A beautifully preserved mandible of Libonectes atlasense, an elasmosaurid plesiosaur from early Turonian, Upper Cretaceous,  deposits of the Akrabou Formation near Asfla Village, Goulmima, Errachidia Province in eastern central Morocco.

The collecting area is in the region of Drâa-Tafilalet. You may know Errachidia as Ksar Souk. It was renamed My Rachid, in honour of the Moroccan royal family. Libonectes is a genus of sauropterygian reptile belonging to the plesiosaurs. Specimens have been found in the Britton Formation of Texas and the Akrabou Formation of Morocco.

Sauropterygian reptiles were a diverse taxon of extinct aquatic reptiles that arose from terrestrial ancestors just after the Permian extinction event. They flourished during the Triassic then all but the plesiosaurs became extinct at the end of the Triassic — with the plesiosaurs dying out at the end of the Cretaceous.

The holotype of Libonectes atlasense is an almost complete skeleton from Upper Cretaceous (mid-Turonian) rocks of the Goulmima area in eastern Morocco. Sven Sachs from the Naturkunde-Museum Bielefeld and Benjamin P. Kear from Uppsala University co-authored a paper redescribing the elasmosaurid plesiosaurian Libonectes atlasense from the Upper Cretaceous of Morocco. They did an initial assessment of the specimen in 2005, proposing a generic referral based on stratigraphical contemporaneity with Libonectes morgani from the CenomanianeTuronian of Texas, U.S.A.

Relative differences in the profile of the premaxillary-maxillary tooth row, position of the external bony nasal opening, number of teeth and rostrad inclination of the mandibular symphysis, proportions of the axial neural arch, and number of cervical and pectoral vertebrae were used to distinguish between these species.

Libonectes Scale Drawing / Hyrotrioskjan
As part of an on-going comparative appraisal of elasmosaurid plesiosaurian osteo-anatomy, they re-examined the type and formally referred material of both L. atlasense and L. morgani in order to establish species validity, as well as compile a comparative atlas for use in future works.

Their work revealed that these reportedly distinct species-level fossils are in fact virtually indistinguishable in gross morphology.

Indeed, the only substantial difference occurs in relative prominence of the midline keel along the mandibular symphysis, which might be explained by intraspecific variation. Their observations permit an amendment to the published generic diagnosis of Libonectes with the confirmation of important states such as the likely presence of a pectoral bar, distocaudad expansion of the humerus, and an epipodial foramen.

And we see some entirely new features. Novel features include a prominent ‘prong-like’ ventral midline process on the coracoids and the development of a median pelvic bar that encloses a central fenestration. Their work shows that the composite remains of L. morgani thus constitute one of the most complete elasmosaurid skeletal hypodigms documented worldwide, and evidence a trans-Atlantic distribution for this apparently dispersive species during the early Late Cretaceous. The impressive mandible you see here is in the collection of Andy Chua.

Sachs, Sven and Kear, Benjamin. (2017). Redescription of the elasmosaurid plesiosaurian Libonectes atlasense from the Upper Cretaceous of Morocco. Cretaceous Research. 74. 205-222. 10.1016/j.cretres.2017.02.017.

Photo: Libonectes atlasense specimen, Andy Chua

Drawing By Hyrotrioskjan - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=57716018

Saturday, 28 March 2020

ICHTHYOSAURS, SHARKS AND BLUBBER

We've learned much about the mighty ichthyosaur since first discovering their bones in Wales back in 1699. That's over three hundred years of knowledge to process.

We'll we've classified them as an extinct order of marine reptiles from the Mesozoic era. We know that they were visibly dolphin-like in appearance and share some other qualities as well. They were warm-blooded, used their coloration as camouflage and had insulating blubber to keep them warm.

Ichthyosaurs are interesting because they have many traits in common with dolphins, but are not at all closely related to those sea-dwelling mammals. We aren't exactly sure of their biology either. They have many features in common with living marine reptiles like sea turtles, but we know from the fossil record that they gave live birth, which is associated with warm-bloodedness. This study reveals some of those biological mysteries.

We find their fossil remains in outcrops spanning the mid-Cretaceous to the earliest Triassic. As we look through the fossils, we see a slow evolution in body design moving towards that enjoyed by dolphins and tuna by the Upper Triassic, albeit with a narrower, more pointed snout.

Johan Lindgren, Associate Professor at Sweden's Lund University and lead author on the paper,  described the 180 million-year-old specimen, Stenopterygius, from outcrops in the Holzmaden quarry in Germany.

Both the body outline and remnants of internal organs are clearly visible in the specimen. Remarkably, the fossil is so well-preserved that it is possible to observe individual cellular layers within its skin.

Stenopterygius quadriscissus
Researchers identified cell-like microstructures containing pigment organelles on the surface of the fossil.

This ancient skin revealed a feature we recognized from marine dwelling animals, the ability to change colour, providing camouflage from potential predators. They also found traces of what might have been the animal's liver.

When they put some of the tissue through chemical analysis, it was consistent with what we'd look for in adipose tissue or blubber. Not surprising as dolphins today use blubber for buoyancy and to help to thermally insulate for thermal regulation in cold seas. It's a highly useful adaptation and one that led me to wonder what other vertebrates might use blubber or some other adaptation to maintain a warmer body temperature independent of icy cold conditions.

Today, blubber is an important part of the anatomy of seals, walruses and whales. It covers the core of their bodies, storing energy, insulating them from cold seas and providing extra buoyancy. 

A rather fetching Walrus, Odobenus rosmarus
Fat and blubber are not the same. The main differences are their consistency and blood supply —  blubber contains many more blood vessels than fat, and is far denser because it's made up of a mix of collagen fibres and lipids.

Blubber layers can be incredibly thick. Walruses deposit most of their body fat into a thick layer of blubber — a layer of fat reinforced by fibrous connective tissue that lies just below the skin of most marine mammals.

This blubber layer insulates the walrus and streamlines its body. It also functions as an energy reserve. Blubber covers the core of their bodies but does not grace their fins, flippers and flukes.

Not all marine animals need blubber. Our cold-blooded marine friends: sharks, crabs, fish, are able to let their body temperatures dropdown to very chilly levels, some as low as 36 degrees Fahrenheit.

They have a few tricks up their sleeves to make this happen. Sharks have evolved specialized physiology to keep their metabolic rate high and their hearts are able to contract in the icy depths because of a special protein. These adaptations allow sharks to enjoy a wide range of habitats and follow their food from warm tropical seas to the icy waters of the North Pacific.

Gray Shark, Carcharhinus amblyrhynchos
With the advent of genetics, we've now learned that the Great White Shark’s genetic code and many of the proteins they use to control metabolism are more closely related to humans than zebrafish, the quintessential fish model.

In a very cool bit of science, researchers sequenced a shark's heart transcriptome – the messenger molecules produced from the shark’s genome, including those active in making proteins. Then they categorized the proteins based on their functions.

What they found that the proportions of white shark proteins in many categories matched humans more closely than zebrafish. Of particular interest was that white shark had a closer match to humans for proteins involved in metabolism. Great White Sharks have a rare trait in fish called regional endothermy. This allows them to keep the body temperature of some of their organs warmer than the ambient water — a highly useful trait for fast swimming, digestion and hunting in colder waters.

References and additional reading:

Fancy a read? Check out the work by Michael Stanhope, professor of evolutionary genomics at Cornell’s College of Veterinary Medicine, and scientists at the Save Our Seas Shark Research Center at Nova Southeastern University (NSU). He published the shark genetic study in the November 2013 issue of BMC Genomics. It lays the foundation for genomic exploration of sharks and vastly expands genetic tools for their conservation.

Johan Lindgren, Peter Sjövall, Volker Thiel, Wenxia Zheng, Shosuke Ito, Kazumasa Wakamatsu, Rolf Hauff, Benjamin P. Kear, Anders Engdahl, Carl Alwmark, Mats E. Eriksson, Martin Jarenmark, Sven Sachs, Per E. Ahlberg, Federica Marone, Takeo Kuriyama, Ola Gustafsson, Per Malmberg, Aurélien Thomen, Irene Rodríguez-Meizoso, Per Uvdal, Makoto Ojika, Mary H. Schweitzer. Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur. Nature, 2018; DOI: 10.1038/s41586-018-0775-x

North Carolina State University. (2018, December 5). Soft tissue shows Jurassic ichthyosaur was warm-blooded, had blubber and camouflage. ScienceDaily. Retrieved September 7, 2019, from www.sciencedaily.com/releases/2018/12/181205134118.htm

Photo: By Haplochromis - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5825284

Friday, 27 March 2020

ICHTHYOSAUR BASIOCCIPITAL BONE AND TELEOST FISH

Ichthyosaur Basioccipital Bone / Liam Langley
A very exciting find of an Ichthyosaur basioccipital bone. This is the bone next to the skull that connected to the vertebrae. He found this in situ so not very water warn as you might expect. This lovely bone was found by the deeply awesome Liam Langley on the Yorkshire Coast.

Ichthyosaurs became extinct during the Upper Cretaceous, about 30 million years before the K/T extinction event. There was an ocean anoxic event at the Cenomanian–Turonian stage boundary. The deeper layers of the seas became anoxic and poisoned by hydrogen sulphide. As life died off in the lower (benthos) levels of the sea, so did the predators at the top of the food chain. The last pliosaurs and ichthyosaurs became extinct.

Ichthyosaurs had been dwindling in numbers for some time; they were no longer the force they once were in the Upper Triassic and Lower Jurassic. By the middle Jurassic, it was thought they all belonged to the single clade, the Ophthalmosauridae. By the Cretaceous, it was thought that only three genera survived. For the last 50+ years, it has been thought that only one genus, Platypterygius, was known at the time of the anoxic event in the Upper Cretaceous.

Ichthyosaur Basioccipital Bone / Liam Langley
There was still diversity in ichthyosaurs a few million years before the extinction event. They may have survived right up to the extinction event. Ichthyosaurs had declined from their peak.

By the Cretaceous, they certainly had more competitors than in the Triassic and more elusive prey. The adaptive radiation of teleost fish meant their new prey was fast swimming and highly evasive.

The difference between teleosts and other bony fish lies mainly in their jawbones; teleosts have a movable premaxilla and corresponding modifications in the jaw musculature which make it possible for them to protrude their jaws outwards from the mouth.

This is of great advantage, enabling them to grab prey and draw it into the mouth. In more derived teleosts, the enlarged premaxilla is the main tooth-bearing bone, and the maxilla, which is attached to the lower jaw, acts as a lever, pushing and pulling the premaxilla as the mouth is opened and closed. Other bones further back in the mouth serve to grind and swallow food.

Another difference is that the upper and lower lobes of the tail (caudal) fin are about equal in size. The spine ends at the caudal peduncle, distinguishing this group from other fish in which the spine extends into the upper lobe of the tail fin.

The most basal of the living teleosts are the Elopomorpha, eels and their allies, and the Osteoglossomorpha, those whacky elephantfish and their friends. There are over 800 species of elopomorphs; each with thin leaf-shaped larvae known as leptocephali specialized for a marine environment.

Among the elopomorphs, eels have elongated bodies with lost pelvic girdles and ribs and fused elements in the upper jaw. The 200 species of osteoglossomorphs are defined by a bony element in the tongue. This element has a basibranchial behind it, and both structures have large teeth that are paired with the teeth on the parasphenoid in the roof of the mouth.

The clade Otocephala includes the Clupeiformes, tasty herrings, and Ostariophysi  — carp, catfish and their friends. Clupeiformes are made up of 350 living species of herring and herring-like fish. This group is characterized by an unusual abdominal scute and a different arrangement of the hypurals. In most species, the swim bladder extends to the braincase and plays a role in hearing. Ostariophysi, which includes most freshwater fishes, has developed some unique adaptations.

One is the Weberian apparatus, an arrangement of bones, called Weberian ossicles, connecting the swim bladder to the inner ear. This enhances their hearing, as sound waves make the bladder vibrate, and the bones transport the vibrations to the inner ear. They also have a chemical alarm system; when a fish is injured, the warning substance gets in the water, alarming nearby fish. Excellent for the predatory fish, less so for their poor injured brethren.

The teleosts included fast-swimming predatory fish, which would have been competing for similar food resources to our ichthyosaur friends. Had they complained about the teleosts they would have been deeply aghast to know what was coming next — big, hungry mosasaurs. The ichthyosaurs and pliosaurs were replaced in the marine ecology by the giant mosasaurs. The mosasaurs were probably ambush-hunters, whose sit-and-wait strategy apparently proved most successful. So, teleost fish, the ocean anoxic event and the rise of mosasaurs all contributed to the end of the ichthyosaurs.

Photos 1-2: By the awesome Liam Langley
Image 3: By Sir Francis Day - Fauna of British India, Fishes (www.archive.org), Public Domain, https://commons.wikimedia.org/w/index.php?curid=1919094

Thursday, 26 March 2020

INDIGO: NATURAL DYES

Natural dyes are dyes or colourants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources — roots, berries, bark, leaves, and wood — and other biological sources such as fungi and lichens.

Archaeologists have found evidence of textile dyeing dating back to the Neolithic period. In China, dyeing with plants, barks and insects has been traced back more than 5,000 years and looks to be our first attempt at the practice of chemistry.

The essential process of dyeing changed little over time. Typically, the dye material is put in a pot of water and then the textiles to be dyed are added to the pot, which is heated and stirred until the colour is transferred. Sometimes, we use workers with stout marching legs to mix this up.

Traditional dye works still operate in many parts of the world. There is a revival of using natural indigo in modern Egypt — although their indigo dye is mostly imported. The same is true further south in Sudan. They've been importing cloth from Upper Egypt as far back as we have written records and continue the practice of the cloth and dye imports today. Clean white cotton is more the style of western Sudan and Chad, but they still like to throw in a bit of colour.

Traditional Dye Vats
So do the folk living in North Africa. Years ago, I was travelling in Marrakesh and saw many men with noticeably orange, blueish or purplish legs. It wasn't one or two but dozens of men and I'd wondered why this was.

My guide took me to the top of a building so I could look down on rows and rows of coloured vats. In every other one was a man marching in place to work the dye into the wool. Their legs took on the colour from their daily march in place in huge tubs of liquid dye and sheared wool. This wool would be considered textile fibre dyed before spinning — dyed in the wool — but most textiles are yarn-dyed or piece-dyed after weaving.

Many natural dyes require the use of chemicals called mordants to bind the dye to the textile fibres; tannin from oak galls, salt, natural alum, vinegar, and ammonia from stale urine were staples of the early dyers.

Many mordants and some dyes themselves produce strong odours. Urine is a bit stinky. Not surprisingly, large-scale dyeworks were often isolated in their own districts.

Woad, Isatis tinctoria
Plant-based dyes such as Woad, Isatis tinctoria, indigo, saffron, and madder were raised commercially and were important trade goods in the economies of Asia and Europe. Across Asia and Africa, patterned fabrics were produced using resist dyeing techniques to control the absorption of colour in piece-dyed cloth.

Dyes such as cochineal and logwood, Haematoxylum campechianum, were brought to Europe by the Spanish treasure fleets, and the dyestuffs of Europe were carried by colonists to America.

Throughout history, people have dyed their textiles using common, locally available materials, but scarce dyestuffs that produced brilliant and permanent colours such as the natural invertebrate dyes. Crimson kermes became highly prized luxury items in the ancient and medieval world. Red, yellow and orange shades were fairly easy to procure as they exist as common colourants of plants. It was blue that people sought most of all and purple even more so.


Indigofera tinctoria, a member of the legume or bean family proved just the trick. This lovely plant —  named by the famous Swedish botanist Carl Linneaus, the father of formalized binomial nomenclature — grows in tropical to temperate Asia and subtropical regions, including parts of Africa.

The plants contain the glycoside indican, a molecule that contains a nitrogenous indoxyl molecule with some glucose playing piggyback. Indigo dye is a product of the reaction of indoxyl by a mild oxidizing agent, usually just good old oxygen.

To make the lovely blue and purple dyes, we harvest the plants and ferment them in vats with urine and ash. The fermentation splits off the glucose, a wee bit of oxygen mixes in with the air (with those sturdy legs helping) and we get indigotin — the happy luxury dye of royalty, emperors and kings.

While much of our early dye came from plants — now it is mostly synthesized — other critters played a role. Members of the large and varied taxonomic family of predatory sea snails, marine gastropod mollusks, commonly known as murex snails were harvested by the Phoenicians for the vivid dye known as Tyrian purple.

While the extant specimens maintained their royal lineage for quite some time; at least until we were able to manufacture synthetic dyes, it was their fossil brethren that first captured my attention. There are about 1,200 fossil species in the family Muricidae. They first appear in the fossil record during the Aptian of the Cretaceous.

Their ornate shells fossilize beautifully. I'd first read about them in Addicott's Miocene Gastropods and Biostratigraphy of the Kern River Area, California. It's a wonderful survey of 182 early and middle Miocene gastropod taxa.

References:

George E.Radwin and Anthony D'Attilio: The Murex shells of the World, Stanford University press, 1976, ISBN 0-8047-0897-5

Pappalardo P., Rodríguez-Serrano E. & Fernández M. (2014). "Correlated Evolution between Mode of Larval Development and Habitat in Muricid Gastropods". PLoS ONE 9(4): e94104. doi:10.1371/journal.pone.0094104

Miocene Gastropods and Biostratigraphy of the Kern River Area, California; United States Geological Survey Professional Paper 642  This article incorporates text from this source, which is in the public domain.

Wednesday, 25 March 2020

FOSSILS, TEXTILES AND URINE

You may recall the eight-metre Type Specimen of the ichthyosaur, Temnodontosaurus crassimanus, found in an alum quarry in Yorkshire.

The Yorkshire Museum was given this important ichthyosaur fossil back in 1857 when alum production was still a necessary staple of the textile industry. Without that industry, many wonderful specimens would likely never have been unearthed.

These quarries are an interesting bit of British history as they helped shape the Yorkshire Coast, created an entirely new industry and gave us more than a fixative for dyes. With them came the discovery of many remarkable fossil specimens and, oddly, local employment in the collection of urine.

In the 16th century, alum was essential in the textile industry as a fixative for dyes. By the first half of the 16th century, the clothing of the Low Countries, German states, and Scandinavia had developed in a different direction than that of England, France, and Italy, although all absorbed the sobering and formal influence of Spanish dress after the mid-1520s. Those fashions held true until the Inquisition when both politics and fashion underwent a much-needed overhaul to something lighter.

Fashion in Medieval Livonia (1521): Albrecht Dürer
Elaborate slashing was popular, especially in Germany. In the depiction you see here, an artist pokes a bit of fun at Germanic fashion from the time. Bobbin lace arose from passementerie in the mid-16th century in Flanders, the Flemish Dutch-speaking northern portion of Belgium. Black was increasingly worn for the most formal occasions.

This century saw the rise of the ruff, which grew from a mere ruffle at the neckline to immense, slightly silly, cartwheel shapes. They adorned the necklines of the ultra-wealthy and uber-stylish men and women of the age.

At their most extravagant, ruffs required wire supports and were made of fine Italian reticella, a cutwork linen lace.

16th Century Fashion / Ruff Collars and Finery
In contrast to all that ruff, lace and cutwork linen, folk needed dyed fabrics. And to fix those dyes, they needed Alum. For a time, Italy was the source of that alum.

The Pope held a tidy monopoly on the industry, supplying both alum and the best dyes. He also did a nice trade in the colourful and rare pigments for painting. And for a time, all was well with dandy's strutting their finery to the local fops in Britain.

All that changed during the Reformation. Great Britain, heathens as they were, were cut-off from their Papal source and found themselves needing to fend for themselves.

The good Thomas Challoner took up the charge and set up Britain's first Alum works in Guisborough. Challoner looked to paleontology for inspiration. Noticing that the fossils found on the Yorkshire coast were very similar to those found in the Alum quarries in Europe, he hatched a plan to set-up an alum industry on home soil. As the industry grew, sites along the coast were favoured as access to the shales and subsequent transportation was much easier.

Alum House, Photo: Joyce Dobson and Keith Bowers
Alum was extracted from quarried shales through a large scale and complicated process which took months to complete. The process involved extracting then burning huge piles of shale for 9 months, before transferring it to leaching pits to extract an aluminum sulphate liquor. This was sent along channels to the alum works where human urine was added.

At the peak of alum production, the industry required 200 tonnes of urine every year. That's the equivalent of all the potty visits of more than 1,000 people. Yes, strange but true.

The steady demand was hard to keep up with and urine became an imported resource from markets as far away as London and Newcastle upon Tyne in the northeast of England. Wooden buckets were left on street corners for folk to do their business then carted back to the south to complete the alum extraction process. The urine and alum would be mixed into a thick liquid. Once mixed, the aromatic slosh was left to settle and then the alum crystals were removed.

I'm not sure if this is a folktale or plain truth, but as the story goes, one knows when the optimum amount of alum had been extracted as you can pop an egg in the bucket and it floats on its own.

Alum House. Photo: Ann Wedgewood and Keith Bowers
The last Alum works on the Yorkshire Coast closed in 1871. This was due to the invention of manufacturing synthetic alum in 1855, then subsequently the creation of aniline dyes that contained their own fixative.

There are many sites along the Yorkshire Coast which bear evidence of the alum industry. These include Loftus Alum Quarries where the cliff profile is drastically changed by extraction and huge shale tips remain.

Further South are the Ravenscar Alum Works, which are well preserved and enable visitors to visualize the processes which took place. The photos you see here are of Alum House at Hummersea. The first shows the ruin of Alum House printed on a postcard from 1906. The second (bottom) image shows the same ruin from on high with Cattersty Point in the background.

The good folk at the National Trust in Swindon are to thank for much of the background shared here. If you'd like to learn more about the Yorkshire area or donate to a very worthy charity, follow their link below.

Reference: https://www.nationaltrust.org.uk/yorkshire-coast/features/how-alum-shaped-the-yorkshire-coast