Tuesday, 24 November 2020

HERMIT CRAB: REAL ESTATE TYCOONS

This little cutie is a hermit crab and he is wearing a temporary home borrowed from one of our mollusc friends. 

His body is a soft, squishy spiral that he eases into the perfect size shell time and time again as he grows. 

His first choice is always the empty shell of a marine snail but will get inventive in a pinch — nuts, wood, serpulid worm tubes, aluminium cans or wee plastic caps. 

They are inventive, polite and patient. 

You see, a hermit crabs' desire for the perfect bit of real estate will have them queueing beside larger shells — shells too large for them — to wait upon a big hermit crab to come along, discard the perfect home and slip into their new curved abode. This is all done in an orderly fashion with the hermit crabs all lined up, biggest to smallest to see who best fits the newly available shell. 

There are over 800 species of hermit crab — decapod crustaceans of the superfamily Paguroidea. Their lineage dates back to the Jurassic, 200 million years ago. Their soft squishy, weakly calcified bodies do not fossilize all that often but when they do the specimens are spectacular. Think of all the species of molluscs these lovelies have had a chance to try on — including ammonites — and all the shells that were never buried in sediment to become fossils because they were harvested as homes.  

On the shores of British Columbia, Canada, the hermit crab I come across most often is the Grainyhand hermit crab, Pagurus granosimanus

These wee fellows have tell-tale orange-brown antennae and olive green legs speckled with blue or white dots. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, a shell is known as x̱ala̱'is and gugwis means house on the beach. 

I do not know the Kwak’wala word for a hermit crab, so I will think of these cuties as x̱ala̱'is gugwis — envisioning them finding the perfect sized shell on the surf worn shores of Tsax̱is, Fort Rupert, Vancouver Island. 

Monday, 23 November 2020

WEYLA OF THE SUNRISE FORMATION

Weyla (Nielsen, 1963) New York Canyon, Nevada
A lovely example of the large bivalve, Weyla (Nielsen, 1963), from the earliest known Jurassic Ferguson Hill Member (Hettangian and Sinemurian) of the Sunrise Formation in the New York Canyon area of west-central Nevada, USA.

The end-Triassic mass extinction was global, severe, and accompanied by worldwide disturbance to carbonate ramp and platform sedimentation. We see the effects played out in the Ferguson Hill Member of the Sunrise Formation. These outcrops are the result of the earliest known Jurassic carbonate ramp produced in the back-arc basin along NE Panthalassa following the extinction event to determine the biotic constituents and timing of local ecological recovery.

The Ferguson Hill Member (Hettangian and Sinemurian) of the Sunrise Formation in the New York Canyon area of west-central Nevada, USA has a lovely counterpart in the Rockies of British Columbia, Canada, explored over three field seasons in the early 2000s before being closed off as a provincial park.

In the Hettangian, post-extinction biosiliceous sedimentation extended to the inner ramp, where an ooid and grapestone shoal marked the outermost extent of a narrow belt of carbonate sedimentation. An early recovery phase in the late Hettangian is characterized by widespread, laterally homogeneous, demosponge-dominated level-bottom sedimentation across the mid- to inner-ramp, in addition to limited trophic tiering (sessile epifaunal suspension-feeding and mobile infaunal deposit-feeding), substantial ramp aggradation, and poor settling conditions for competitive benthic colonizers (e.g., corals, crinoids, infaunal bivalves).

Within 1.6–2 Myr after the extinction (in the early Sinemurian), a late recovery phase is recognized by the appearance of epifaunal grazers (gastropods, echinoids) and suspension feeders (crinoids, solitary scleractinian corals), phototrophic microbialites (oncoids, and possibly photosymbionts within corals), and infaunal deposit or suspension feeders (bivalves).

Although the late recovery faunas included more trophic levels than pre-extinction carbonate ramp habitats, development and progradation of the first Jurassic carbonate ramp still relied heavily on sponge, microbialite, and abiotic mineralization.

Sunday, 22 November 2020

JURASSIC SUNRISE FORMATION OF NEVADA

The entrance to the Pliensbachian-Toarcian localities at Joker Peak and Mina Peak Members of the Sunrise Formation, Nevada, USA.

The Jurassic ammonites of this section were first studied by Dr. Paul Smith, past Chair of Earth and Ocean Sciences, University of British Columbia and more recently by Andrew Caruthers et al.

Caruthers and his team took a goodly look at the Early Jurassic coral fauna. It is nice to see the other marine invertebrates getting the attention they deserve. Caruthers is an interesting cat. He uses a combination of invertebrate palaeontology and isotope geochemistry to ponder the effects of paleoclimate change and mass extinction. He has turned his eye in recent years to the Paleozoic of the Michigan Basin AND he's based in Kalamazoo, MI. Yep, Kalamazoo.

Others have taken up the mantle of discovery from these sites. Pengfei Hou did his 2014 Masters thesis comparing the Sinemurian (Early Jurassic) stratigraphic sections of Last Creek, British Columbia and Five Card Draw, Nevada including a detailed taxonomic study from the Involutum Zone to the lower part of the Harbledownense Zone of the Sinemurian.

Saturday, 21 November 2020

ICHTHYOSAUR RIB SECTION

A tasty ichthyosaur block with three distinct vertebrae and some ribs just peeking out. You can see the edges of the ribs nicely outlined against the matrix of this lovely articulated block. This beauty is but one piece of a complete ichthyosaur found in situ in Middle Triassic (Anisian/Ladinian) outcrops in the West Humboldt Mountains, Nevada.

Ichthyosaurs are an extinct order of marine reptiles from the Mesozoic era. They evolved from land-dwelling, lung-breathing reptiles, they returned to our ancient seas and evolved into the fish-shaped creatures we find in the fossil record today.

They were visibly dolphin-like in appearance but seem to share some other qualities as well. These lovelies were warm-blooded and used their colouration as camouflage. The smaller of their lineage to avoid being eaten and the larger to avoid being seen by prey. Ichthyosaurs also had insulating blubber, a lovely adaptation to keep them warm in cold seas.

Over time, their limbs fully transformed into flippers, sometimes containing a very large number of digits and phalanges. Their flippers tell us they were entirely aquatic as they were not well-designed for use on land. And it was their flippers that first gave us the clue that they gave birth to live young; a hypothesis later confirmed by fossil embryo and wee baby ichy specimens.

We find their fossil remains in outcrops spanning from 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. 

During the early Triassic, ichthyosaurs evolved from a group of unidentified land reptiles that returned to the sea. They were particularly abundant in the later Triassic and early Jurassic periods before being replaced as a premier aquatic predator by another marine reptilian group, the Plesiosauria, in the later Jurassic and Cretaceous. 

Friday, 20 November 2020

HOPLOSCAPHITES NEBRASCENSIS


This sweet macroconch with her lovely oil-in-water colouring is a Hoploscaphites nebrascensis (Owen, 1852). This is the female form of the ammonite that has a larger shell than the male, or microconch.

Hoploscaphites nebrascensis is an upper Maastrichtian species and index fossil. It marks the top of ammonite zonation for the Western Interior. This species has been recorded from Fox Hills Formation in North and South Dakota as well as the Pierre Shale in southeastern South Dakota and northeastern Nebraska.

It is unknown from Montana, Wyoming, and Colorado due to the deposition of coeval terrestrial units. It has possibly been recorded in glacial deposits in Saskatchewan and northern North Dakota, but that is hearsay. 

Outside the Western Interior, this species has been found in Maryland and possibly Texas in the Discoscaphites Conrad zone. This lovely one is in the collection of the deeply awesome (and enviable) José Juárez Ruiz. A big thank you to Joshua DrSlattmaster J Slattery for his insights on this species.

Thursday, 19 November 2020

EUHOPLITES OF FOLKSTONE

Euhoplites Ammonite, Collection of José Juárez Ruiz
A beautiful Euhoplites ammonite from Folkstone, UK. Euhoplites is an extinct ammonoid cephalopod from the Lower Cretaceous, characterized by strongly ribbed, more or less evolute, compressed to inflated shells with flat or concave ribs, typically with a deep narrow groove running down the middle.

In some, ribs seem to zigzag between umbilical tubercles and parallel ventrolateral clavi. In others, the ribs curve forward from the umbilical shoulder and lap onto either side of the venter.

Its shell is covered in the lovely lumps and bumps we associate with the genus. The function of these adornments are unknown. I wonder if they gave them greater strength to go deeper into the ocean to hunt for food. 

They look to have been a source of hydrodynamic drag, likely preventing Euhoplites from swimming at speed. Studying them may give some insight into the lifestyle of this ancient marine predator. Euhoplites had shells ranging in size up to a 5-6cm. We find them in Lower Cretaceous, middle to upper Albian age strata. Euhoplites has been found in Middle and Upper Albian beds in France where it is associated respectively with Hoplites and Anahoplites, and Pleurohoplites, Puzosia, and Desmoceras; in the Middle Albian of Brazil with Anahoplites and Turrilites; and in the Cenomanian of Texas.

This species is the most common ammonite from the Folkstone Fossil Beds in southeastern England where a variety of species are found, including this 37mm beauty from the collections of José Juárez Ruiz.

Wednesday, 18 November 2020

FORT RUPERT / TSAXIS

One of the most beautiful areas of Vancouver Island is the town of Port Hardy on the north end of the island. 

Just outside Port Hardy further south on the west coast is the area known as Fort Rupert or Tsaxis. 

It was here that the Hudson's Bay Company built Fort Rupert both for trade with the local First Nation population and the allure of potential coal deposits. 

I headed up to the north island this past week to stomp around my old haunts and visit with family. 

The town was much as I remembered it. There have been changes, of course. I lived up on Wally's hill above the reserve at Tsaxis beside the old cemetery. I was blessed to stay with my cousin Valerie Hart and her partner, Ron. Their home is beautiful and the perfect launch point for exploring the north island.

My wee childhood home is still there and I am very pleased to see that the earthly home of my ancestors is well maintained. The cemetery is groomed and cared for but the land surrounding it is overgrown and it took me a few minutes to orient myself to see where things used to be. Where the old Hudson's Bay Company fort and its iconic chimney were in relation to the graveyard. 

I had hoped to spend some blissful days taking photos of the scenery but arrived during a hurricane, quite literally. 

The beachhead here was clocking 120 km winds so I did a brief visit to the homestead, the graveyard and Jokerville then headed home to light the fire and hunker in as the storm blew through. 

Port Harty and Fort Rupert have an interesting history and how you read it or hear it truly depends on the lens that is applied. This has been the ancestral home to many First Nation groups. Mostly they were passing through and coming here to dig up delicious butter clams, roots, berries and other natural yummy goodness. Years before Port Hardy was settled at the turn of the century it was the home to the Kwakiutl or Kwagu’ł, a mix of First Nation peoples from the north coast and part of my heritage. 

Sunday, 15 November 2020

TALES FROM HAIDA GWAII

A wreck with tales to tell at Naikoon, Haida Gwaii. The islands have gone by many names. To the people who call the islands home, Haida Gwaii means “island of the people,” it is a shortened version of an earlier name, Haadala Gwaii-ai, or “taken out of concealment.” 

Back at the time of Nangkilslas, it was called Didakwaa Gwaii, or “shoreward country.” By any name, the islands are a place of rugged beauty and spirit and enjoy a special place in both the natural and supernatural world. The enormous difference between high and low tide in Haida Gwaii – up to twenty three vertical feet – means that twice a day, vast swathes of shellfish are unveiled, free for the taking. 

An ancient Haida saying is still often heard today, “When the tide is out, the table is set.” Archaeological evidence shows that by about five thousand years ago, gathering shellfish replaced hunting and fishing as their primary food source. The shellfish meat was skewered on sticks, smoked and stored for use in winter or for travel.

Steeped in mist and mythology, the islands of Haida Gwaii abound in local lore that surrounds their beginnings. Today, the Hecate Strait is a tempestuous 40-mile wide channel that separates the mist-shrouded archipelago of Haida Gwaii from the BC mainland. Haida oral tradition tells of a time when the strait was mostly dry, dotted here and there with lakes. During the last ice age, glaciers locked up so much water that the sea level was hundreds of feet lower than it is today. Soil samples from the sea floor contain wood, pollen, and other terrestrial plant materials that tell of a tundra-like environment.

The islands of Haida Gwaii are at the western edge of the continental shelf and form part of Wrangellia, an exotic terrane of former island arcs, which also includes Vancouver Island, parts of western mainland British Columbia and southern Alaska. 

Brewericeras hulenense (Anderson, 1938)
While we’ll see that there are two competing schools of thought on Wrangellia’s more recent history, both sides agree that many of the rocks, and the fossils they contain, were laid down somewhere near the equator. 

They had a long, arduous journey, first being pushed by advancing plates, then being uplifted, intruded, folded, and finally thrust up again. It’s reminiscent of how pastry is balled up, kneaded over and over, finally rolled out, then the process is repeated again.

This violent history applies to most of the rock that makes up the Insular Belt, the outermost edge of the Cordillera. Once in their present location, the rocks that make up the mountains and valleys of this island group were glaciated and eroded to their present form. Despite this tumultuous past, the islands have arguably the best-preserved and most fossil-rich rocks in the Canadian Cordillera, dating from very recent to more than 200 million years old. 

The fossils found in the Triassic rock of Wrangellia are equatorial or low latitude life forms quite different from those found today on the Continent at the latitude of Haida Gwaii. This suggests those rocks were in the equatorial region during the Late Triassic, just over 200 million years ago. 

The Lower Jurassic ammonite faunas found at Haida Gwaii are very similar to those found in the Eastern Pacific around South America and in the Mediterranean. The strata exposed at Maple Island, Haida Gwaii are stratigraphically higher than the majority of Albian localities in Skidegate Inlet. The macrofossil fauna belonged to the Upper part of the Sandstone Member of the Haida formation.

The western end of the island contains numerous well-preserved inoceramids such as Birostrina concentrica and a few rare ammonites of Desmoceras bearskinese. The eastern shores are home to unusual ammonite fauna in the finer grained sandstones. Here we find the fossils as extremely hard concretions while others were loose in the shale. Species include Anagaudryceras sacya and Tetragonites subtimotheanus. A large whorl section of the rare Ammonoceratites crenucostatus has also been found here. The ammonites, Desmoceras; Brewericeras hulenense; Cleoniceras perezianum, Douvelliceras spiniferum are all found in Lower Cretaceous, Middle Albian, Haida Formation deposits.

Friday, 13 November 2020

DOUVELLICERAS SPINIFERUM

Douvelliceras spiniferum, Cretaceous Haida Formation
The islands of Haida Gwaii lay at the western edge of the continental shelf due west of the central coast of British Columbia. 

They form Wrangellia, an exotic tectonostratigraphic terrane that includes Vancouver Island, parts western British Columbia and Alaska.

The Geological Survey of Canada (GSC) sponsored many expeditions to these remote islands and has produced numerous reference papers on this magnificent terrain, exploring both the geology and palaeontology of the area.

Joseph Whiteaves, the GSC's chief palaeontologist in Ottawa, published a paper in 1876 describing the Jurassic and Cretaceous faunas of Skidegate Inlet, furthering his reputation globally as both a geologist and palaeontologist.

The praise was well-earned and foreshadowed his significant contributions to come. Sixteen years later, he wrote up and published his observations on a strange Mount Stephen fossil that resembled a kind of headless shrimp with poorly preserved appendages. Because of the unusual pointed shape of the supposed ventral appendages and the position of the spines near the posterior of the animal, Whiteaves named it Anomalocaris canadensis. The genus name "Anomalocaris" meant "unlike other shrimps" and the species name — canadensis — refers, of course, to the country of origin and my home.

Whiteaves work on the palaeontology of Haida Gwaii provided excellent reference tools, particularly his work on the Cretaceous exposures and fauna that can be found there.

One of our fossil field trips was to the ruggedly beautiful Cretaceous exposures of Lina Island. We’d planned this trip as part of our “trips of a lifetime.” Both John Fam and Dan Bowen can be congratulated for their efforts in researching the area and ably coordinating a warm welcome by the First Nations community and organizing fossil field trips to some of the most amazing fossil localities in the Pacific Northwest. With great sandstone beach exposures, the fossil-rich (Albian to Cenomanian) Haida formation provided ample specimens, some directly in the bedding planes and many in concretion. Many of the concretions contained multiple specimens of typical Haida Formation fauna, providing a window into this Cretaceous landscape.

It is always interesting to see who was making a living and co-existing in our ancient oceans at the time these fossils were laid down. We found multiple beautifully preserved specimens of the spiny ammonite, Douvelleiceras spiniferum along with Brewericeras hulenense, Cleoniceras perezianum and many cycads in concretion.

Pictured above is Douvilleiceras spiniferum with his naturally occurring black, shiny appearance. Choosing my favourite fossil is a tricky business as there are so many wonderful specimens to choose from but if I had to choose, this would be my favourite. This satisfying chunky monkey is 6 inches long and 5 inches deep, and a beautiful example of the species. Missing from this trip log are tales of Rene Savenye, who passed away in the weeks before this trip. While he wasn't there in body, he was with us in spirit. I thought of him often on the mist-shrouded days of collecting. Many of the folk on who joined me on those outcrops were friends of Rene's and would go on to receive the Rene Savenye Award. There is a certain palaeo poetry in that. 

Thursday, 12 November 2020

BRACHIOPODA: LOPHOTROCHOZOANS

Looking down at the pebbly sand, you see just the wee top of this lovely fossil brachiopod poking out. Glee, delight and wonder follow as you roll it over in your hands and notice how it differs from clams you may be more familiar with.

Clams or bivalves are molluscs, the second-largest phylum of invertebrates with about 85,000 extant species. While brachiopods share some similarities with their molluscan friends they are in a phylum all their own.

Brachiopods are small marine shellfish that are not so common today but back in the Palaeozoic they were plentiful the world over. The two valves that make up a brachiopods shell are of different sizes and if you look closely you'll see that the hinge runs top and bottom  -- versus left and right like a clam.

Brachiopods had evolved from an ancestor similar to Halkieria, a slug-like Cambrian animal with "chain mail" on its back and a shell at the front and rear end; it was thought that the ancestral brachiopod converted its shells into a pair of valves by folding the rear part of its body under its front. 

New fossils found in the last few years have shown us that the "chain mail" of tommotiids formed the tube of a sessile animal; one tommotiid resembled phoronids, which are close relatives or a subgroup of brachiopods, while the other tommotiid bore two symmetrical plates that might be an early form of brachiopod valves. Lineages of brachiopods that have both fossil and extant taxa appeared in the early Cambrian, Ordovician, and Carboniferous periods, respectively. 

Other lineages have arisen and then become extinct, sometimes during severe mass extinctions. At their peak in the Paleozoic era, the brachiopods were among the most abundant filter-feeders and reef-builders and occupied other ecological niches, including swimming in the jet-propulsion style of scallops. Brachiopod fossils have been useful indicators of climate changes during the Paleozoic. However, after the Permian–Triassic extinction event, brachiopods recovered only a third of their former diversity. 

Brachiopods were especially vulnerable to the Permian–Triassic extinction, as they built calcareous hard parts — made of calcium carbonate — and had low metabolic rates and weak respiratory systems. It was often thought that brachiopods went into decline after the Permian–Triassic extinction, and were out-competed by bivalves, but both brachiopod and bivalve species increased from the Paleozoic to modern times, with bivalves increasing faster; after the Permian–Triassic extinction, brachiopods became for the first time less diverse than bivalves.

Their lineage dates back to the Cambrian with over 12,000 fossil species and 350 living relatives sorted between 6,000 genera. There are two major groups of brachiopods, articulate with toothed hinges and simple open and closing muscles to manipulate their shells and inarticulate brachiopods with untoothed hinges and a more complex set of muscles used to control the brachial supports used to open and close their shells.

Wednesday, 11 November 2020

FOSSIL BONANZA: LAGERSTÄTTEN

Florissantia from Quilchena
Highly recommend the tasty paleo goodies shared on the Fossil Bonanza website and podcast. Both sites are dedicated to Fossil-Lagerstätten — the passion of Andy Connolly, a museum educator out of Utah. 

Fossil-Lagerstätten are unusual fossil sites found across the globe. A Lagerstätte is a sedimentary deposit with extraordinary fossils preservation. If we are truly lucky, this includes the preservation of soft tissues in remarkable detail. 

Fossil-Lagerstätten can be formed in a number of ways. Sometimes an animal or plant is buried in an anoxic or low oxygen environment with minimal bacteria to break down the organic material. In this case, decomposition is minimized. 

Even better if the burial happens quickly so that no scavengers can enjoy a tasty snack and the entire specimen is preserved. This type of burial preserves both the gross and fine biological features. If you look at the Florissantia petals above, they look like you may have pressed a modern blossom between the pages of a book. While this lovely is from Ypresian, Early Eocene, deposits near Quilchena, British Columbia, it looks as though it could reasonably have been plucked this year. In the case of Quilchena, the perfect blossom was preserved in a lakebed setting with fine silt that quickly covered and pressed down upon the pedals so that they are preserved here as impressions and carbonaceous films.

The Earth occasionally blesses us with Lagerstätten which can amass thousands, sometimes millions of preserved fossils in stunning quality. Birds can be found with their bones perfectly intact and feathers arranged in a beautiful display. 

Flowers are captured in full bloom — as in the case of the lovely Florissantia above — and leaves look as if they had just fallen from a tree. Even amber-entombed insects have their tiny, delicate hairs untouched. Some of these fossil sites are quite well known: La Brea Tar Pits in California or Dinosaur National Monument in Utah and Colorado. 

Others fly under the collective radar — Grube Messel in Germany or the Naracoorte Caves in Australia. Nevertheless — these sites all contribute vast quantities of knowledge about our ancient worlds and fill in the gaps that would otherwise be empty forever. 

Konservat-Lagerstätten preserves lightly sclerotized and soft-bodied organisms or traces of organisms that are not otherwise preserved in the usual shelly and bony fossil record; thus, they offer more complete records of ancient biodiversity and behaviour and enable some reconstruction of the palaeoecology of ancient aquatic communities. 

In 1986, Simon Conway Morris calculated only about 14% of genera in the Burgess Shale had possessed biomineralized tissues in life. The affinities of the shelly elements of conodonts were mysterious until the associated soft tissues were discovered near Edinburgh, Scotland, in the Granton Lower Oil Shale of the Carboniferous. 

Information from the broader range of organisms found in Lagerstätten has contributed to recent phylogenetic reconstructions of some major metazoan groups. Lagerstätten seem to be temporally autocorrelated, perhaps because global environmental factors such as climate might affect their deposition

I've popped the link here for you. Definitely worth checking out! https://fossilbonanza.com/about/

Sunday, 8 November 2020

BURGESS, WALCOTT & WAVING CAMBRIAN WORMS

High up in the Canadian Rockies in an area known as Burgess Pass is one of the most unlikely, perfect and improbable fossil sites on Earth. The Burgess Shale sits high up on the glacier-carved cliffs of the Canadian Rockies.

The fine-grained shales from the Burgess were once part of the ancient landmass known as Laurentia, the ancient geologic core of the North American continent, and are home to some of the most diverse and well-preserved fossils in the world. The sedimentary shales here contain fossils that open a window to marine life half a billion years old.

The site is made up of a few quarries and includes the Stephen Formation — Mount Wapta and Mount Field — and the upper Walcott Quarry with its Phyllopod Bed. There is also a lower quarry named for Professor Piercy Raymond who opened the site in 1924.

It is one of the rare locations in the world where both soft tissues and hard body parts have been fossilized amidst the layers of black shale that form Fossil Ridge and the surrounding areas.

Discovered just over a hundred years ago on an unlikely day in 1909 by Charles D. Walcott, the site has continued to wow scientists and the community at large year after year. Charles was in Canada after losing his first wife to a train crash in Connecticut. He met Mary Morris Vaux, an amateur naturalist from a wealthy family and this new love and her interest in the wilds of Canada had brought him back.

Walcott was a geologist, palaeontologist and administrator of the Smithsonian Institution in Washington, DC, USA. He was an expert in Cambrian fossils for his time. A company man, he joined the US Geological Survey in 1879 and rose to become a director in 1894.  He served as President of the American Association for the Advancement of Science in 1923 and was an advisor to President Theodore Roosevelt.

Picture the world at this time. Coca-Cola sold their first soft drink, in Germany, Wilhelm Roentgen developed the first x-ray and it was a year before the United States Supreme Court ruled that "separate but equal" public facilities for whites and blacks ought to be legal.

So, up and coming Walcott was up exploring in the Rockies and stopped to rest his horse. Always a rock man, he had his hammer handy and split some likely blocks. They contained trilobites and other arthropods now famous from the site.

While he recognized the significance of the site, it wasn’t until 1960 through the work of Alberot Simonella and others that the Burgess received the scientific attention it deserved.

In 1967, Harry Whittington initiated the Cambridge Project to re-open the Burgess files and build on the work of his predecessors. He brought two grad students on board to do the heavy lifting as a means to publish or perish. Simon Conway Morris (Worms) and Derek Briggs (Arthropods) completed the trio and together they formed the foundation of what was to become some of the most significant work of our time.

Imagine the first palaeontologists working on these weird and wonderful specimens. Wondering at the strange and unlikely creatures made real before their eyes. It is a rare and exquisite thing to see soft-bodied organisms fossilized.

Every year, a new species or magnificent specimen is unearthed. In 2011, a hiker discovered a rare fossil of Ovatiovemis, a genus of filter-feeding lobopodians. Picture a marine worm with nine arms waving to you. Yep, that’s him. The specimen she found is now described as Ovatiovermis cribratus and is one of only two known specimens of Oviatiovermis from the Burgess.

This important site in the Canadian Rockies has been awarded protection as a UNESCO World Heritage Site (1981) in recognition of the exceptional fossil preservation and diversity of the species found here.

With countless hours of research and study, we now know the Burgess Shale contains the best record we have of Cambrian animal fossils. It reveals the most complete record of creatures that proliferated the Earth showcasing the Cambrian explosion 545 to 525 million years ago.

It was a time of oceanic life in all its splendour. The land may have been inhospitable, barren and uninhabited but our oceans were teeming with new species. Great soft fine-grained mudslides slid onto an ecosystem in a deep-water basin. Millions of years later, this unlikely event was revealed to us through the fossils preserved at Burgess.

Photo: The view from Burgess Pass

Thursday, 5 November 2020

HOLCOPHYLLOCERAS MEDITERRANEUM

There is delightful suturing on this lovely ammonite, Holcophylloceras mediterraneum, (Neumayr 1871) from Late Jurassic (Oxfordian) deposits near Sokoja, Madagasgar.

The shells had many chambers divided by walls called septa. The chambers were connected by a tube called a siphuncle which allowed for the control of buoyancy with the hollow inner chambers of the shell acting as air tanks to help them float.

We can see the edges of this specimen's shell where it would have continued out to the last chamber, the body chamber, where the ammonite lived. Picture a squid or octopus, now add a shell and a ton of water. That's him!

They were prolific breeders that evolved rapidly. If you could cast a fishing line into our ancient seas, it is likely that you would hook an ammonite, not a fish. They were prolific back in the day, living (and sometimes dying) in schools in oceans around the globe. We find ammonite fossils (and plenty of them) in sedimentary rock from all over the world.

In some cases, we find rock beds where we can see evidence of a new species that evolved, lived and died out in such a short time span that we can walk through time, following the course of evolution using ammonites as a window into the past.

For this reason, they make excellent index fossils. An index fossil is a species that allows us to link a particular rock formation, layered in time with a particular species or genus found there. Generally, deeper is older, so we use the sedimentary layers rock to match up to specific geologic time periods, rather the way we use tree-rings to date trees. A handy way to compare fossils and date strata across the globe.

Tuesday, 3 November 2020

DRIFTWOOD CANYON BIRDS

Secretary Bird, Sagittarius serpentarius
Driftwood Canyon Provincial Park is a provincial park in British Columbia, Canada. Driftwood Canyon Provincial Park covers 23 ha of the Bulkley River Valley, on the east side of Driftwood Creek, a tributary of the Bulkley River, 10 km northeast of the town of Smithers. 

The parklands are part of the asserted traditional territory of the Wet'suwet'en First Nation which includes lands around the Bulkley River, Burns Lake, Broman Lake, and François Lake in the northwestern Central Interior of British Columbia. 

The Wetʼsuwetʼen are a branch of the Dakelh or Carrier people, and in combination with the Babine people have been referred to as the Western Carrier. They speak Witsuwitʼen, a dialect of the Babine-Witsuwitʼen language which, like its sister language Carrier, is a member of the Athabaskan family.

Their oral history or kungax recounts a time when their ancestral village, Dizkle or Dzilke, once stood upstream from the Bulkley Canyon. This cluster of cedar houses on both sides of the river was said to be abandoned because of an omen of impending disaster. The exact location of the village has been lost. The neighbouring Gitxsan people of the Hazelton area have a similar tale, though the village in their version is referred to as Dimlahamid or Temlahan. Their house groups include the Gilseyhu or Big Frog Clan, the Laksilyu or Small Frog Clan, the Tsayu or Beaver Clan, the Gitdumden or Wolf and Bear Clan and the Laksamshu or Fireweed and Owl Clan.

The park was created in 1967 by the donation of the land by the late Gordon Harvey (1913–1976) to protect fossil beds on the east side of Driftwood Creek. The beds were discovered around the beginning of the 20th century. 

Driftwood Canyon is recognized as one of the world’s most significant fossil beds. It provides park users with a fascinating opportunity to understand the area’s evolutionary processes of both geology and biology. Bird feathers are infrequently collected from the shales; however, two bird body fossils have been found here.

In 1968, a bird body fossil was collected in the Eocene shales of the Ootsa Lake Group in Driftwood Canyon Provincial Park by Pat Petley of Kamloops. Pat Petley donated the specimen in 2000 to the Thompson Rivers University (TRU) palaeontology collections. This fossil bird specimen is tentatively identified as puffbird, Piciformes Bucconidae, of the genus Primobucco.

Primobucco is an extinct genus of bird placed in its own family, Primobucconidae. The type species, Primobucco mcgrewi, lived during the Lower Eocene of North America. It was initially described by American paleo-ornithologist Pierce Brodkorb in 1970, from a fossil right-wing, and thought to be an early puffbird. However, the discovery of a further 12 fossils in 2010 indicate that it is instead an early type of roller.

Related fossils from the European Messel deposits have been assigned to the two species P. perneri and P. frugilegus. Two specimens of P. frugilegus have been found with seeds in the area of their digestive tract, which suggests that these birds were more omnivorous than the exclusively predaceous modern rollers. The Driftwood specimen has never been thoroughly studied. If there is a grad student out there looking for a worthy thesis, head on down to the Thompson Rivers University where you'll find the specimen on display.

Another fossil bird, complete with feathers, was collected at Driftwood Canyon in 1970, This one was found by Margret and Albrecht Klöckner who were travelling from Germany. Theirs is a well-travelled specimen, having visited many sites in BC as they toured around, then to Germany and finally back to British Columbia when it was repatriated and donated to the Royal British Columbia Museum in Victoria. I'm not sure if it is still on display or back in collections, but it was lovingly displayed back in 2008. There is a new grad student, Alexis, looking at Eocene bird feathers down at the RBCM, so perhaps it is once again doing the rounds. 

This second bird fossil is of a long-legged water bird and has been tentatively identified by Dr. Gareth Dyke of the University of Southampton as possibly from the order Charadriiformes, a diverse order of small to medium-ish water birds that include 350 species of gulls, plovers, sandpipers, terns, snipes, and waders. Hopefully, we'll hear more on this find in the future.

If you fancy a visit to Driftwood Canyon Park, the park is accessible from Driftwood Road from Provincial Highway 16. You are welcome to view and photograph the fossils found here but collecting is strictly forbidden. 

https://vancouversun.com/news/local-news/citizen-archeologists-help-fill-in-50-million-year-old-blanks-in-b-c-s-history

Saturday, 31 October 2020

OH KEUPPIA: ANCIENT OCTOPUS FROM LEBANON

An adorable example of Keuppia levante (Fuchs, Bracchi & Weis, 2009), an extinct genus of octopus that swam our ancient seas back in the Cretaceous. The dark black and brown area you see is his ink sac which has been preserved for a remarkable 95 million years.

This cutie is in the family Palaeoctopodidae, and one of the earliest representatives of the order Octopoda. These ancient marine beauties are in the class Cephalopoda making them relatives of our modern octopus, squid and cuttlefish.

There are two species of Keuppia, Keuppia hyperbolaris and Keuppia levante, both of which we find as fossils. We find their remains, along with those of the genus Styletoctopus, in Cretaceous-age Hâqel and Hjoula localities in Lebanon. For many years, Palaeoctopus newboldi (Woodward, 1896) from the Santonian limestones at Sâhel Aalma, Lebanon, was the only known pre‐Cenozoic coleoid cephalopod believed to have an unambiguous stem‐lineage representative of Octobrachia fioroni

With the unearthing of some extraordinary specimens with exquisite soft‐part preservation in the Lebanon limestones, our understanding of ancient octopus morphology has blossomed. The specimens are from the sub‐lithographical limestones of Hâqel and Hâdjoula, in north‐west Lebanon. These localities are about 15 km apart, 45 km away from Beirut and 15 km away from the coastal city of Jbail. Fuchs et al. put a nice little map in their 2009 paper that I've included and referenced here.

Palaeoctopus newboldi had a spherical mantle sac, a head‐mantle fusion, eight equal arms armed with suckers, an ink sac, a medially isolated shell vestige, and a pair of (sub‐) terminal fins. The bipartite shell vestige suggests that Palaeoctopus belongs to the octopod stem‐lineage, as the sister taxon of the Octopoda, the Cirroctopoda, is characterized by an unpaired clasp‐like shell vestige (Engeser 1988; Haas 2002; Bizikov 2004).

It is from the comparisons of Canadian fauna combined with those from Lebanon and Japan that things really started to get interesting with fossil Octobrachia. Working with fossil specimens from the Campanian of Canada, Fuchs et al. (2007a ) published on the first record of an unpaired, saddle‐shaped shell vestige that might have belonged to a cirroctopod. 

Again from the Santonian–Campanian of Canada and Japan, Tanabe et al. (2008) reported on at least four different jaw morphotypes. Two of them (Paleocirroteuthis haggarti  Tanabe et al. , 2008 and Paleocirroteuthis pacifica  Tanabe et al ., 2008) have been interpreted as being of cirroctopod type, one of octopod type, and one of uncertain octobrachiate type. 

Interestingly Fuchs et al. have gone on to describe the second species of Palaeoctopus, the Turonian Palaeoctopus pelagicus from limestones at Vallecillo, Mexico. While more of this fauna will likely be recovered in time, their work is based solely on a medially isolated shell vestige.

Five new specimens have been found in the well-known Upper Cenomanian limestones at Hâqel and Hâdjoula in Lebanon that can be reliably placed within the Octopoda. Fuchs et al. described these exceptionally well‐preserved specimens and to discuss their morphology in the context of phylogeny and evolution in their 2008 paper (2009 publishing) in the Palaeontology Association Journal, Volume 51, Issue 1.

The presence of a gladius vestige in this genus shows a transition from squid to octopus in which the inner shell has divided in two in early forms to eventually be reduced to lateralized stylets, as can be seen in Styletoctopus.

The adorable fellow you see here with his remarkable soft-bodied preservation and inks sack and beak clearly visible is Keuppia levante. He hails from Late Cretaceous (Upper Cenomanian) limestone deposits near Hâdjoula, northwestern Lebanon. The vampyropod coleoid, Glyphiteuthis abisaadiorum n. sp., is also found at this locality. This specimen is about 5 cm long.

Fuchs, D.; Bracchi, G.; Weis, R. (2009). "New octopods (Cephalopoda: Coleoidea) from the Late Cretaceous (Upper Cenomanian) of Hâkel and Hâdjoula, Lebanon". Palaeontology. 52: 65–81. doi:10.1111/j.1475-4983.2008.00828.x.

Photo one: Fossil Huntress. Figure Two: Topographic map of north‐western Lebanon with the outcrop area in the upper right-hand corner. Fuchs et al, 2009.  

Friday, 30 October 2020

PADDLING PARADISE: THE BOWRON LAKES

A cool morning breeze keeps the mosquitoes down as we pack our kayaks and gear for today’s paddling journey. 

It is day four of our holiday, with two days driving up from Vancouver to Cache Creek, past the Eocene insect and plant site at McAbee, the well-bedded Permian limestone near Marble Canyon and onto Bowron Provincial Park, a geologic gem near the gold rush town of Barkerville.

The initial draw for me, given that collecting in a provincial park is forbidden and all collecting close at hand outside the park appears to amount to a handful of crushed crinoid bits and a few conodonts, was the gorgeous natural scenery and a broad range of species extant. It was also the proposition of padding the Bowron Canoe Circuit, a 149,207-hectare geologic wonderland, where a fortuitous combination of plate tectonics and glacial erosion have carved an unusual 116-kilometre near-continuous rectangular circuit of lakes, streams and rivers bound on all sides by snowcapped mountains. From all descriptions, something like heaven.

The east and south sides of the route are bound by the imposing white peaks of the Cariboo Mountains, the northern boundary of the Interior wet belt, rising up across the Rocky Mountain Trench, and the Isaac Formation, the oldest of seven formations that make up the Cariboo Group (Struik, 1988). 

Some 270 million-plus years ago, had one wanted to buy waterfront property in what is now British Columbia, you’d be looking somewhere between Prince George and the Alberta border. The rest of the province had yet to arrive but would be made up of over twenty major terranes from around the Pacific. The rock that would eventually become the Cariboo Mountains and form the lakes and valleys of Bowron was far out in the Pacific Ocean, down near the equator.

With tectonic shifting, these rocks drifted north-eastward, riding their continental plate, until they collided with and joined the Cordillera in what is now British Columbia. Continued pressure and volcanic activity helped create the tremendous slopes of the Cariboo Range we see today with repeated bouts of glaciation during the Pleistocene carving their final shape.

We brace our way into a headwind along the east side of the fjord-like Isaac Lake. Paddling in time to the wind, I soak up the view of this vast, deep green, ocean-like expanse that runs L-shape for nearly 38 kilometres, forming nearly half of the total circuit. The rock we paddle past is primarily calcareous phyllite, limestone and quartzite, typical of the type locality for this group and considered upper Proterozoic (Young, 1969), the time in our geologic history between the first algae and the first multicellular animals. It is striking how much this lake fits exactly how you might picture pristine wilderness paddling in your mind’s eye. No powerboats, no city hum, just pure silence, broken only by the sound of my paddle pulling through the water and the occasional burst of glee from one of the park’s many songbirds.

We’ve chosen kayaks over the more-popular canoes for this journey, as I got to experience my first taste of the handling capabilities of a canoe last year in Valhalla Provincial Park. The raised sides acted like sails and kept us off course in all but the lightest conditions. This year, Philip Torrens, Leanne Sylvest, and I were making our trek in low profile, Kevlar style. One single & one double kayak would be our faithful companions and mode of transport. They would also be briefly conscripted into service as a bear shield later in the trip.

Versatile those kayaks.

The area is home to a variety of plant life. Large sections of the forest floor are carpeted in the green and white of dogwood, a prolific ground cover we are lucky enough to see in full bloom. Moss, mushrooms and small wildflowers grow on every available surface. Yellow Lily line pathways and float in the cold, clear lake water. Somewhere I read a suggestion to bring a bathing suit to the park, but at the moment, I cannot imagine lowering anything more than my paddle into these icy waters. To reach the west side of the paddling route, we must first face several kilometres portaging muddy trails to meet up with the Isaac River and then paddle rapids to grade two.

At the launch site, we meet up with two fellow kayakers, Adele and Mary of Victoria, and take advantage of their preceding us to watch the path they choose through the rapids. It has been raining in the area for forty plus days, so the water they run is high and fast. Hot on their heels, our short, thrilling ride along the Isaac River, is a flurry of paddle spray and playing around amid all the stumps, silt and conglomerate. 

The accommodation gods smile kindly on us as we are pushed out from Isaac River and settle into McLeary Lake. An old trapper cabin built by local Freddie Becker back in the 1930s, sits vacant and inviting, providing a welcome place to hang our hats and dry out. From here we can see several moose, large, lumbering, peaceful animals, the largest members of the deer family, feeding on the grass-like sedge on the far shore. The next morning, we paddle leisurely down the slower, silt-laden Cariboo River, avoiding the occasional deadhead, and make our way into the milky, glacier-fed Lanezi Lake.

Like most mountainous areas, Bowron makes its own weather system and it appears you get everything in a 24-hour period. In fact, whatever weather you are enjoying seems to change 40 minutes later; good for rain, bad for sun. 

Wisps of cloud that seemed light and airy only hours early have become dark. Careful to hug the shore, we are ready for a quick escape from lightning as thundershowers break.

Paddling in the rain, I notice bits of mica in the water, playing in the light and the rock here changes to greywacke, argillite, phyllite and schist. Past Lanezi, we continue onto Sandy Lake, where old-growth cedars line the south-facing slopes to our left and grey limestone, shale and dolostone line the shore. 

Mottled in with the rock, we sneak up on very convincing stumps posing as large mammals. Picking up the Cariboo River again, we follow it as it flows into Babcock Lake, an area edged with Lower Cambrian limestone, shale and argillite. At the time these rocks were laid down, the Earth was seeing our earliest relatives, the first chordates entering the geologic scene.

As we reach the end of Babcock Lake and prepare for our next portage I get my camera out to take advantage of the angle of the sun and the eroded rounded hilltops of the Quesnel Highlands that stand as a backdrop.

Leanne remarks that she can see a moose a little ways off and that it appeared to be heading our way. Yes, heading our way quickly with a baby moose in tow. I lift my lens to immortalize the moment and we three realized the moose are heading our way in double time because they are being chased by a grizzly — at top speed. 

A full-grown moose can run up to fifty-six kilometres per hour, slightly faster than a Grizzly. They are also strong swimmers. Had she been alone, Mamma moose would likely have tried to outswim the bear. Currently, however, this is not the case. From where we stand we can see the water turned to white foam at their feet as they fly towards us.

We freeze — bear spray in hand.

In seconds the three were upon us. Mamma moose, using home-field advantage, runs straight for us and just reaching our boats, turned 90 degrees, bolting for the woods, baby moose fast on her heels.

The Grizzly, caught up in the froth of running and thrill of the kill, doesn’t notice the deke, hits the brakes at the boats and stands up, confused. Her eyes give her away. This was not what she had planned and the whole moose-suddenly-transformed-into-human thing is giving her pause. Her head tilts back as she gets a good smell of us.

Suddenly, a crack in the woods catches her attention. Her head snaps around and she drops back on all fours, beginning her chase anew. Somewhere there is a terrified mother moose and calf hoping the distance gained is enough to keep them from being lunch. I choose to believe both moose got away with the unwitting distraction we provided, but I’m certainly grateful we did.

The Lakes are at an elevation of over 900 m (3000 ft) and both grizzly and black bear sightings are common. Both bear families descend from a common ancestor, Ursavus, a bear-dog the size of a raccoon who lived more than 20 million years ago. Seems an implausible lineage having just met one of the larger descendants. While we’d grumbled only hours earlier about how tired we were feeling, we now feel quite motivated and do the next two portages and lakes in good time. 

Aside from the gripping fear that another bear encounter is imminent, we enjoy the park-like setting, careful to scan the stands of birch trees for dark shapes now posing as stumps. Fortunately, the only wildlife we see are a few wily chipmunks, various reticent warblers and some equally shy spruce grouse.

The wind favours us now as we paddle Skoi and Spectacle Lake, even giving us a chance to use the sails we’ve rigged to add an extra knot of oomph to our efforts. Reaching the golden land of safety-in-numbers, we leap from our kayaks, happy to see the smiling faces of Mary and Adele.

Making it here is doubly thrilling because it means I am sleeping indoors tonight and I can tell the bear story with adrenaline still pumping through my veins. Tonight is all about camaraderie and the warmth of a campfire. Gobbling down Philip’s famous pizza, Leanne impresses everyone further by telling of his adventures in the arctic and surviving a polar bear attack.

This is our first starlit night without rain, a luxury everyone comments on, but quietly, not wanting to jinx it. We share a good laugh at the expense of the local common loons — both Homeo sapien sapien and Gavia immer. The marshy areas of the circuit provide a wonderful habitat for the regions many birds including a host of sleek, almost regal black and white common loons.

Their cool demeanour by day is reduced to surprisingly loud, maniacal hoots and yelps with undignified flapping and flailing by night. It seems hardly possible that these awful noises could be coming from the same birds and that this has been going for nearly 65 million years, since the end of the age of dinosaurs, as loons are one of the oldest bird families in the fossil record.

A guitar is pulled out to liven the quiet night while small offerings, sacred and scare this late in our journey, are passed around. Tonight is a celebration that we have all, both separately and together, made our way around this immense mountain-edged circuit.

Wednesday, 28 October 2020

RISE OF FLOWERING PLANTS: CROCUS

Crocus Flowers: Saffron & Dye
The earliest flowering plants show up in the fossil record 130 million years ago. These beauties became the dominant type of forest plant by about 90 million years ago. One of their number, the genus Crocus, is a particular favourite of mine.

Crocus — the plural of which is crocuses or croci — is a genus of flowering plants in the iris family and includes 90 species of perennials growing from corms. A corm is a short, swollen underground plant stem that helps plants survive summer drought and other less favourable conditions. The name Crocus is derived from the Latin adjective crocatus, meaning saffron yellow. The Greek word for "saffron" is krokos, while the Arabic word saffron or zafaran, means yellow. 

Many are cultivated for their flowers appearing in autumn, winter, or spring. The spice saffron is obtained from the stigmas of Crocus sativus, an autumn-blooming species.

Each crocus flower plucked gently by hand yields three vivid strands of saffron with an acre of laborious work producing only a few pounds.

The challenge of harvesting saffron from crocus and its high-market value dates back to 2100-1600 BC as the Egyptians, Greeks, and the Minoans of Crete all cultivated crocus not as a spice, but as a dye. 

Roman women used saffron to dye their hair and textiles yellow. The crocus corm has a history of trade throughout Europe that a few pounds of corms served as a loan of gold or jewels. It made it's way into the writing of the Greeks as early as 300 BC where it originated. 

The precious flower travelled to Turkey and then all the way to Great Britain in the 1500s before making their way to the rest of the world. The first crocus in the Netherlands came from corms brought back from the Roman Empire in the 1560s. A few corms were forwarded to Carolus Clusius at the botanical garden in Leiden. By 1620, new garden varieties had been developed, such as the cream-coloured crocus similar to varieties we see in flower markets and local gardens today. 

Sunday, 25 October 2020

CRETACEOUS HADROSAUR TOOTH

A rare and very beautifully preserved Cretaceous Hadrosaur Tooth. This lovely specimen is from one of our beloved herbivorous "Duck-Billed" dinosaurs from 68 million-year-old outcrops near Drumheller, Alberta, Canada, and is likely from an Edmontosaurus.

When you scour the badlands of southern Alberta, most of the dinosaur material you'll find are from hadrosaurs. These lovely tree-less valleys make for excellent-searching grounds and have led us to know more about hadrosaur anatomy, evolution, and paleobiology than for most other dinosaurs.

We have oodles of very tasty specimens and data to work with. We've got great skin impressions and scale patterns from at least ten species and interesting pathological specimens that provide valuable insights into hadrosaur behaviour. Locally, we have an excellent specimen you can visit in the Courtenay and District Museum on Vancouver Island, Canada. The first hadrosaur bones were found on Vancouver Island a few years back by Mike Trask, VIPS, on the Trent River near Courtenay.

The Courtenay hadrosaur is a first in British Columbia, but our sister province of Alberta has them en masse. Given the ideal collecting grounds, many of the papers on hadrosaurs focus on our Canadian finds. These herbivorous beauties are also found in Europe, South America, Mexico, Mongolia, China, and Russia. Hadrosaurs had teeth arranged in stacks designed for grinding and crushing, similar to how you might picture a cow munching away on the grass in a field. These complex rows of "dental batteries" contained up to 300 individual teeth in each jaw ramus. But even with this great number, we rarely see them as individual specimens.

They didn't appear to shed them all that often. Older teeth that are normally shed in our general understanding of vertebrate dentition, were resorped, meaning that their wee osteoclasts broke down the tooth tissue and reabsorbed the yummy minerals and calcium.

As the deeply awesome Mike Boyd notes, "this is an especially lucky find as hadrosaurs did not normally shed so much as a tooth, except as the result of an accident when feeding or after death. Typically, these fascinating dinosaurs ground away their teeth... almost to nothing."

In hadrosaurs, the root of the tooth formed part of the grinding surface as opposed to a crown covering over the core of the tooth. And curiously, they developed this dental arrangement from their embryonic state, through to hatchling then full adult.

There's some great research being done by Aaron LeBlanc, Robert R. Reisz, David C. Evans and Alida M. Bailleul. They published in BMC Evolutionary Biology on work that looks at the histology of hadrosaurid teeth analyzing them through cross-sections. Jon Tennant did a nice summary of their research. I've included both a link to the original journal article and Jon Tennant's blog below.

LeBlanc et al. are one of the first teams to look at the development of the tissues making up hadrosaur teeth, analyzing the tissue and growth series (like rings of a tree) to see just how these complex tooth batteries formed.

They undertook the first comprehensive, tissue-level study of dental ontogeny in hadrosaurids using several intact maxillary and dentary batteries and compared them to sections of other archosaurs and mammals. They used these comparisons to pinpoint shifts in the ancestral reptilian pattern of tooth ontogeny that allowed hadrosaurids to form complex dental batteries.

References:

LeBlanc et al. (2016) Ontogeny reveals function and evolution of the hadrosaurid dinosaur dental battery, BMC Evolutionary Biology. 16:152, DOI 10.1186/s12862-016-0721-1 (OA link)

To read more from Jon Tennant, visit: https://blogs.plos.org/paleocomm/2016/09/14/all-the-better-to-chew-you-with-my-dear/

Photo credit: Derrick Kersey. For more awesome fossil photos like this from Derrick, visit his page: https://www.facebook.com/prehistoricexpedition/

Saturday, 24 October 2020

HORNBY: THE ECO ISLAND

Hornby is a delightful island off the east coast of Vancouver Island in Georgia Strait. The geology we find here is part of the southern Comox basin. The island lies just east of Denman Island. Texada and Lasqueti lie just to the west.

To reach Hornby, you take a ferry from Buckley Bay on Vancouver island across Baynes Sound to the west side of Denman. You cross this small island and take an even smaller ferry to Hornby.
 
Hornby is home to about 1,000 residents made up of artists, retirees and those wanting to enjoy the quiet, island community-oriented lifestyle.

Hornby Island is formed from sediments of the upper Nanaimo Group which are also widely exposed on adjacent Denman Island and the southern Gulf Islands. 

Peter Mustard, a geologist from the Geologic Survey of Canada, did considerable work on the geology of the island. It has a total stratigraphic thickness of 1350 m of upper Nanaimo Group marine sandstone, conglomerate and shale. These are partially exposed in the Campanian to the lower Maastrichtian outcrops at Collishaw Point on the northwest side of Hornby Island. Four formations underlie the island from oldest to youngest, and from west to east: the Northumberland, Geoffrey, Spray and Gabriola.

During the upper Cretaceous, between ~90 to 65 Ma, sediments derived from the Coast Belt to the east and the Cascades to the southeast poured seaward to the west and northwest into what was the large ancestral Georgia Basin. This major forearc basin was situated between Vancouver Island and the mainland of British Columbia.

The island's soils have developed from marine deposits of variable texture. This is the case for most of Hornby with the exception of the higher elevations and steeper slopes where weathered clastic sedimentary rock provides the parent material. 

Most of Hornby's soils are sandy or gravelly, but some deep black loams occur on the northwestern part of the island. Many of the sands at the southern end have loam-textured topsoils.

Podzols are common and the bleached sand grains associated with their eluvial (A2, Ae or E) horizons lend a salt-and-pepper appearance to many forest trails. 

Podzols are infertile acidic soils that have a white or grey subsurface layer resembling ash. If you look below you'll see that the minerals have been leached into a lower dark-coloured layer. We typically find them under temperate coniferous woodland. 

All of the island's soils on Hornby are strongly acidic. The exception are those which have developed on the shoreline where alkaline shells from shell middens have penetrated the soils.

And it is to the shore that many are drawn — locals, tourists, geologists and palaeontologists alike. Hornby is a wonderful place to explore. The island is beautiful in its own right and the fossils from here often keep some of their original shell or nacre which makes them quite fetching.

The Nanaimo Group as a whole represents largely coarse-grained units deposited in deep-sea fan systems. In this environment, deeper channels continuously cut through successive shale and sandstone bodies. The channels funnelled density currents into the basin, while also building levee deposits. Turbidity currents travelled down the channels, and also overtopped the levees spilling across backslope areas. The sequential sediment formations, from significantly coarse-grained sandstones and conglomerates to fine silts and shale units of the Nanaimo Group, are considered to be partly due to eustacy, but more significantly related to relative sea-level changes induced by regional tectonics in an active forearc setting.

The Northumberland Formation consists of a massive, dark-grey mudstone which is locally interlaminated and interbedded with siltstone and fine-grained sandstone.

There are abundant calcium carbonate concretions, parallel and current ripple laminations, clastic dikes and folded layers due to slumping. 

In the Gulf Islands to the south, this formation has been found to contain abundant and diverse foraminifera indicating marine paleodepths of 150-1200 m. Foraminifera are members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food. Forams have lovely shells that look amazing under a microscope and are hugely useful as wee biostratigraphic markers.

The more resistive Geoffrey Formation is made up of thick-bedded sandstone and conglomerate. It is highly channelized, and some sandstone has exposed parallel and ripple laminations. The Spray Formation exposed on the east end of the island is a massive olive-grey mudstone with interlaminations of sandstone.

Furthest to the east, the youngest exposures on Hornby Island are from the Gabriola Formation, which outcrops on the eastern peninsula. This is again a thick-bedded and channelized sequence of conglomerates and massive sandstone with minor mudstone interbeds. South, in the Gulf Islands, this formation has contained ammonites, gastropods, corals, scaphopods and pelecypods. Some of the nostoceratids previously assigned to Anisoceras cooperi have been divided into five species, two of which are new.

Note: Paleowater-depth from foraminiferal assemblages has been set at 200 m.

Katnick, D.C. and P.S. Mustard (2001): Geology of Denman and Hornby Islands, British Columbia (NTS 92F/7E, 10); British Columbia Geological Survey Branch, Geoscience Map 2001-3.

England, T.D.J. and R. N. Hiscott (1991): Upper Nanaimo Group and younger strata, outer Gulf Islands, southwestern British Columbia: in Current Research, Part E; Geological Survey of Canada, Paper 91-1E, p. 117-125.

Wednesday, 21 October 2020

PERMIAN-TRIASSIC MASS EXTINCTION: EVOLUTIONARY ARMS RACE

Yesterday, on the Fossil Huntress Podcast, we wrestled with the question of whether dinosaurs were warm-blooded or cold-blooded. It is an excellent question and there is good evidence on both sides of that debate.

Many dinosaurs stood upright — a warm-blooded trait. They are also the ancestors of birds who are warm-blooded. Dinosaurs often began life with porous bones, moving to denser bones later in life. This is as much a mark of growth rate as it is for the warm-cold debate. 

And, dinosaurs had small brains relative to body size — a trait of our cold-blooded animals. So, which is it? Cold or warm? My money is on the latter, but we'll likely have some time to wait before we have enough evidence to say for sure one way or the other. One thing we do know to be true is that we see a trend of the Earth's animals moving from cold-bloodedness to warm-bloodedness over time. 

What was the driver for that adaptation? One of the drivers looks to be the Permian-Triassic mass extinction event some 250 million years ago. It was a catastrophic event that killed ninety-five percent of all life on Earth. The remaining species were left to fight for survival against an inhospitable planet and one another. The few surviving species found themselves in a turbulent world —repeatedly hit by ice ages, rapid warming and ocean acidification cycles.

Through all of that, two main groups of tetrapods survived; the synapsids and archosaurs, ancestors of mammals and birds. The ancestors of both mammals and birds became warm-blooded at the same time.

Warm-bloodedness, or endothermy, is the ability to regulate your body temperature using your metabolism rather than relying on the external environment. Humans are endothermic. We eat food and wear warm sweaters to guard against the cold. Warm-bloodedness is key for both survival and reproductive fitness.

There is evidence of warm-bloodedness, including a diaphragm and whiskers in the synapsids as far back as the Triassic. This is supported by a more porous bone structure in both synapsids and archosaurs. Warm-blooded animals tend to have highly vascularized bone tissue. Cold-blooded animals have a denser bone structure that even exhibits annual growth rings. 

Dinosaurs show both traits. They start off life with highly vascularized bone which becomes denser as they mature. This move from vascular to dense bone may have more to do with growth rates than to whether the animals were warm or cold-blooded. 

Another factor in warmth is hair. We know that mammal ancestors had hair from the beginning of the Triassic. More recently, we have learned that archosaurs had feathers from 250 million years ago. Archosaurs are a group of diapsids and are broadly classified as reptiles. The living representatives of this group are birds and crocodilians. It also includes all extinct dinosaurs, pterosaurs, and extinct close relatives of crocodilians. 

Medium-sized and large tetrapods switched from sprawling to erect posture right at the Permian-Triassic boundary. As you know, most warm-blooded animals have an erect or upright posture and our cold-blooded friends tend to walk on all fours. 

The mass posture change and early origin of hair and feathers all speak to the beginning of a species arms race. In ecological terms, an arms race occurs when predators and prey compete on an escalated scale for survival. This pressure caused a rapid change in their evolution as their adaptations escalate. 

When we look at our world today, warm-blooded animals populate all areas of the Earth. They have fewer offspring and show intense parental care, taking months or years to care for their young before they become independent. These adaptations give birds and mammals an edge over amphibians and reptiles and we see this in their domination of the ecosystems in our world.

This revolution in ecosystems was triggered by the independent origins of endothermy in birds and mammals. This particular adaptation lives on as these species survive and thrive in an Earth that can be fickle in terms of environmental conditions.

Reference: Benton, Michael J. The origin of endothermy in synapsids and archosaurs and arms races in 
the Triassic, Gondwana Research, School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol BS8 1TH, UKThe evolution of main groups through the Triassic. Image: Nobu Tamura

Tuesday, 20 October 2020

TITANITES: FERNIE AMMONITE SITE

The Fernie ammonite, Titanites occidentalis, from outcrops on Coal Mountain near Fernie, British Columbia, Canada. 

This beauty is the remains of a carnivorous cephalopod within the family Dorsoplanitidae that lived and died in a shallow sea some 150 million years ago.

If you would like to get off the beaten track and hike up to see this ancient beauty, you will want to head to the town of Fernie in British Columbia close to the Alberta border. 

Driving to the trail base is along an easy access road just east of town along Fernie Coal Road. There are some nice exposures of Cretaceous plant material on the north side (left-hand side) of the road as you head from Fernie towards Coal Creek. I recently drove up to Fernie to look at Cretaceous plant material and locate the access point to the now infamous Late Jurassic (Tithonian) Titanites (S.S. Buckman 1921) site. While the drive out of town is on an easy, well-maintained road, the slog up to the ammonite site is a steep 3-hour push.

The first Titanites occidentalis was about one-third the size and was incorrectly identified as Lytoceras, a fast-moving nektonic carnivore. The specimen you see here is significantly larger at 1.4 metres (about four and a half feet) and rare in North America. 

Titanites occidentalis, the Western Giant, is the second known specimen of this extinct fossil species. The first was discovered in 1947 in nearby Coal Creek by a British Columbia Geophysical Society mapping team.

In the summer of 1947, a field crew was mapping coal outcrops for the BC Geological Survey east of Fernie. One of the students reported finding “a fossil truck tire.” Fair enough. The similarity of size and optics are pretty close to your average Goodridge. 

A few years later, GSC Paleontologist Hans Frebold described and named the fossil Titanites occidentalis after the large Jurassic ammonites from Dorset, England. The name comes from Greek mythology. Tithonus, as you may recall, was the Prince of Troy. He fell in love with Eos, the Greek Goddess of the Dawn. Eos begged Zeus to make her mortal lover immortal. Zeus granted her wish but did not grant Tithonus eternal youth. He did indeed live forever — aging hideously. Ah, Zeus, you old trickster. It is a clever play on time placement. Dawn being the beginning of the day and the Tithonian being the latest age of the Late Jurassic. Clever Hans!

Hiking to the Fernie Ammonite

From the town of Fernie, British Columbia, head east along Coal Creek Road towards Coal Creek. The site is 3.81 km from the base of the Coal Creek Road to the trailhead as the crow flies. I've mapped it here for you in yellow and added the wee purple GPS marker for the ammonite site. There is a nice, dark grey to black roadcut exposure of Cretaceous plants on the north side of the dirt road that is your cue to pull over and park.  

You access the trailhead on the south side of the road. You'll need to cross the creek to begin your ascent. There is no easy way across the creek and you'll want to tackle this one with a friend when the water level is low. The beginning of the trail is not clear but a bit of searching will reveal the trailhead with its telltale signs of previous hikers. This is a 2-3 hour moderate 6.3-kilometre hike up & back bush-whacking through scrub and fallen trees. Heading up, you'll make about a 246-metre elevation gain. You won't have a cellular signal up here but if you download the Google Map to your mobile, you'll have GPS to guide you. 

If you're coming in from out of town, the closest airport is Cranbrook. Then it is about an hour and change to Fernie and another 15-minutes or so to the site.

You'll want to leave your hammers with your vehicle (no need to carry the weight) as this site is best enjoyed with a camera. If you'd like to see the ammonite but are not keen on the hike, a cast has been made by fossil preparator Rod Bartlett and is on display at the Courtenay Museum in Courtenay, Vancouver Island, Canada. 

Fernie Ammonite Palaeo Coordinates: 49°29'04"N 115°00'49"W