BEARS: HARBINGERS OF SPRING

Stretching the legs on a Spring stroll

Some of Vancouver Island’s many bears take a stroll through the wilds in the Comox Valley. 

While stumbling upon them may cause us surprise, they have heard us (and smelled us) coming for miles. 

If you work or play in the woods of British Columbia, both grizzly and black bear sightings are common. 

As Spring arrives with warmer weather and growing daylight, bears begin awakening in the Comox Valley, across Vancouver Island and around the rest of the province, they wake up thirsty and often quench their thirst, then head back to their dens for more sleep. 

As well as parched, some have such powerful hunger they choose to forgo more sleep in favour of beginning the welcome task of searching for food. 

 

Up for a Spring snack but still a bit sleepy

They snack on plant roots, grasses, berries, insects, the shellfish on our coastlines and small mammals—all to replace the many calories they burned off over their winter hibernation. 

Nearly half the world's population, some 26,000 grizzly bears and 380,000 black bears, roam the Canadian wilderness — of those, 14,000 grizzlies and around 140,000-ish black bears call British Columbia home. 

These highly intelligent omnivores lumber along our coastlines, mountains and forests. It is hard to confirm how many live on Vancouver Island, but estimates range from 7,000 to 12,000. 

Bears in the Fossil Record 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 given the size of their enormous descendants. 

Our Island black bears are a little larger than their mainland counterparts. Females can weigh up to almost 400 lbs or (180 kg), and our males get up to 600 lbs or (275 kg) in weight. 

Their beefy cousins get even bigger. An average grizzly weighs in around 800 lbs (363 kg), but a recent find in Alaska tops the charts at 1600 lbs (726 kg). This mighty beast stood 12' 6' high at the shoulder, 14' to the top of his head and is one of the largest grizzlies ever recorded — a na̱ndzi. Adult bears tend to live solo except during mating season. 

Those looking for love congregate from May to July hoping to find a mate. Through adaptation to shifting seasons, the females' reproductive system delays the implantation of fertilised eggs — blastocysts —until November or December to ensure her healthy pups arrive during hibernation. If food resources are slim, the newly formed embryo does not catch or attach to her uterine wall, and she would try again next year. 

Female grizzly bears reach mating maturity at 4-5 years of age. They give birth to a single or up to four cubs (though usually just two) in January or February. The newborn cubs are cute little nuggets — tiny, hairless, and helpless — weighing in at 2-3 kilograms or 4-8 pounds. 

They feast on their mother’s nutrient-dense milk for the first two months of life then stay with their mother for another 16 months or more. 

Once fully grown, they can run 56 km an hour, are good at climbing trees, swimming, and live 20-25 years in the wild. 

Bear encounters bring a humbling appreciation of how remarkable these massive beasts are. Knowing their level of intelligence, keen memory, and bite force of over 8,000,000 pascals — enough to crush a bowling ball — inspires awe and caution in equal measure. 

They have an indescribable presence. It is likely because of this that these majestic bears show up often in the superb carvings and work of First Nations artists. First Nation Lore and Language In the Kwak'wala language of the Kwakwaka'wakw — speakers of Kwak'wala — a grizzly bear is known as nan. 

The ornamental carved grizzly bear headdress worn by the comic Dluwalakha Grizzly Bear Dancers — Once more from Heaven — in the Grizzly Bear Dance or Gaga̱lalał, is known as na̱ng̱a̱mł. 

The Dluwalakha dancers receive supernatural treasures or dloogwi, which they pass down from generation to generation. 

Kwaguʼł Winter Dancers — Qagyuhl 

Should you encounter a black bear and wish to greet them in Kwak'wala, you would call them t̕ła'yi. Kwakiutl First Nations, Smoke of the World, count Grizzly Bears as an ancestor — along with Seagull, Sun and Thunderbird. To tell stories of the ancestors is na̱wiła. 

Smoke of the World / Speaking of the Ancestors — Na̱wiła

Each of these ancestors took off their masks to become human and founded the many groups now bound together by language and culture as Kwakwaka’wakw. Not all Kwakwaka'wakw dance the Gaga̱lalał, but their ancestors likely attended feasts where the great bear was celebrated. To speak or tell stories of the ancestors is na̱wiła — and Grizzly bear as an ancestor is Na̱n Helus. 

Whether ancestor or neighbour, these beautiful creatures live all around us. We may see them moving through our neighbourhoods for food or returning to their habitat. 

It is vital for all of us to be mindful of how our actions impact them and to keep attractants — delicious, smelly garbage and open food — in sealed garbage cans and not outside in open containers. We share this world with them and it is our responsibility to help keep them — and us — safe. 

Reporting Encounters: If you encounter wildlife that is aggressive or causing property damage, call the BC Conservation Officer Service at 1-877-952-7277 (RAPP). 

Bear Aware: BearWise offers great advice helping people live responsibly with bears. You can visit them online at https://bearwise.org/

MEMEKAY JURASSIC AMMONITES OF VANCOUVER ISLAND

Coroniceras sp. from Sayward, British Columbia

This yummy Lower Jurassic ammonite with the creamy dark chocolate colouring is from an all but inaccessible outcrop of the Upper Sinemurian, Bonanza Group,  Harbledownense Zone, Memekay River area, near Sayward, Vancouver Island, British Columbia, Canada. 

This area is home to the We Wai Kai and Wei Wai Kum First Nations and lands of the K'omoks First Nation whose culture thrives and reflects the natural rugged beauty of the central island region.

I will be headed back to these outcrops next month on the way to northern Vancouver Island. 

It is rugged, remote and beautiful. Think trees and valleys for as far as the eye can see. Some of those hillsides on the horizon contain wonderful fossils, including this Coroniceras sp. with the truly marvellous keel.

By the time these ammonites were being buried in sediment, Wrangellia, the predominately volcanic terrane that now forms Vancouver Island and Haida Gwaii, had made its way to the northern mid-latitudes.

Within the basal part of the sequence, sedimentary beds are found interbedded with lapilli and crystal tuffs. Here you'll see maroon tuffaceous sandstone, orange-grey sandstone, granule sandstone and conglomerate. Within them we find ammonites nestled in with gastropods and pelecypods. 

While the fossiliferous outcrop is quite small, the Bonanza group is much larger, estimated to be at least 1000 metres thick. The site is quite small and in an active logging area, so the window to collect is limited. 

We have been to the site many times. One one of the past trips, the drive up the mountain was thrilling as there had just been heavy rains and the road was washed out and narrowed until it was barely the width of our wheelbase and very, very steep. Closer to the top it narrowed to be just shy of the width of the vehicle — thrilling, to say the least. 

So scary that my passengers all got out as there was a high probability of going head-first over the edge. I was navigating by some handwritten field notes and a wee map on a paper napkin that should have read, "park at the bottom and hike up." 

Did we park at the bottom and hike up? No, we did not. 

The torrential rains of the Pacific Northwest had been working their magic on the hillside and slowly washing out the road until it slowly became more of a trail.

At the base of the hillside all looked well. Giddy for the fossils to come, we ventured off with a truck full of enthusiasm. Within 15 minutes of steep elevation gain, we had a wonderful view of the valley below. We were halfway up the mountain before I realized the error of my ways. The road twisted and turned then slowly narrowed to the width of my tires. Too narrow to turn around, so the only way was up. 

Graham Beard from Qualicum Beach was the fellow who showed me the site and drew the wee map for me. I cannot recall everyone on the trip, but Perry Poon was there — he shot a video of the drive up that he described as thrilling. I have never seen it but would like to one day — and so was Patricia Coutts with her lovely Doberman. 

She and I had just done a trip up to Goldbridge where the cliff we were on had turned into a landslide into a ravine so she was feeling understandably cautious about the power of Mother Nature. 

Picture the angle, the hood of my jeep riding high and hiding what remained of the road beneath and a lovely stick shift that made you roll backwards a wee bit with every move to put it into gear. So, without being able to see the very narrow path beneath, I had to just keep going. 

Both Perry and Patricia helped with filling in the potholes so my tires would have something to grip. 

I bent the frame on the jeep heading up and had some explaining to do when I returned it to the car rental place. 

As I recall, I wasn't in my ordinary vehicle but a rental because my car had been stolen the weekend before when I was away with John Fam and Dan Bowen collecting at Jurassic Point, an epic fossil site accessible only by boat on our wild west coast.

Fortuitous timing really, as they stole my car but I had unloaded my precious fossil collecting gear out of the trunk just days before.  

In the end, we found what we were looking for. Memekay yields a mix of ammonites, gastropods and bivalves. 

Many of them are poorly preserved. It was a hell of a ride but well worth the effort as we found some great fossils and with them more information on the palaeontology and geology of Vancouver Island. Just look at the keel on this beauty.

I would share the site information but it is now covered over with debris and inaccessible. One day, this whole region will be developed and the site will be opened up again. Until then, we'll have to enjoy what has been unearthed.

THE DUDLEY BUG: ROLLED TRILOBITES

A lovely rolled trilobite, Calymene blumenbachii,  from outcrops in the UK. This wee beauty is in the collections of the deeply awesome Theresa Paul Spink Dunn — or perhaps in her daughter Layla's collections as she is quite the budding palaeontologist. 

This Silurian beauty is from the Homerian, Wenlock Series, Wrens Nest, Dudley, UK.

I was passing through Qualicum this past week and had an impromptu visit with Graham and Tina Beard. 

They are lifelong friends and avid fossil collectors. Over the past few years, they have traveled to the UK and in passing, Graham mentioned that he had a chance to go to the outcrops where the Dudley Bug can be found. 

His timing was especially fortuitous as the Wenlock Edge quarry is closed now to further collecting but may be open to future research projects. We shall have to wait and see.

Calymene blumenbachii, sometimes erroneously spelled blumenbachi, is a species of trilobite found in the limestone quarries of the Wren's Nest in Dudley, England.

Nicknamed the Dudley Bug or Dudley Locust by an 18th-century quarryman, it became a symbol of the town and featured on the Dudley County Borough Council coat-of-arms. Calymene blumenbachii is commonly found in Silurian rocks (422.5-427.5 million years ago) and is thought to have lived in the shallow waters of the Silurian, in low energy reefs.

This particular species of Calymene — a fairly common genus in the Ordovician-Silurian — is unique to the Wenlock series in England and comes from the Wenlock Limestone Formation in Much Wenlock and the Wren's Nest in Dudley. 

These sites seem to yield trilobites more readily than any other areas on the Wenlock Edge, and the rock here is dark grey as opposed to yellowish or whitish as it appears on other parts of the Edge, just a few miles away, in Church Stretton and elsewhere suggesting local changes in the environment in which the rock was deposited. 

As an aside, while I was in the UK last, I attended a conference in London's Natural History Museum and given a private tour of some of their collections. It was with immense pride that I saw Graham Beard's kind donation to the museum snug up near Darwin. It seems the museum catalogues donations alphabetically so the two collections were quite close to one another. Two great men with a shared love of paleontology across the ages!

YORKSHIRE HISTORY: FOSSILS, TEXTILES AND URINE

Yorkshire Coast

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

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 religious persecution, 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. You can imagine the many hours of skill and patience that would have gone into each piece to create the artful framework of these showy lace collars.

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 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 needed 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 palaeontology 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 aluminium 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.

Many sites along the Yorkshire Coast 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

FOSSIL BIRDS OF SOUTHERN VANCOUVER ISLAND

Stemec suntokum, Sooke Formation

The diving bird you see here is Stemec suntokum, a Fossil Plopterid from Sooke, British Columbia, Canada.

We all dream of finding new species, and new fossil species in particular. This happens more than you think. As impossible as it sounds, it has happened numerous times at many fossils sites in British Columbia including Sooke on Vancouver Island.

The upper Oligocene Sooke Formation outcrops at Muir Beach on southwestern Vancouver Island, British Columbia where it is flanked by the cool, clear waters of the Strait of Juan de Fuca.

While the site has been known since the 1890s, my first trip here was in the early 1990s as part of a Vancouver Paleontological Society (VanPS) fossil field trip. 

This easy, beach walk locality is a wonderful place to collect fossils and is especially good for families. If you are solar-powered, you will enjoy the sun playing off the surf from May through September. If you are built of hardier stuff, then the drizzle of Spring or Autumn is a lovely, un-people-y time to walk the beachfront.

As well as amazing west coast scenery, the beach site outcrop has a lovely soft matrix with well-preserved fossil molluscs, often with the shell material preserved (Clark and Arnold, 1923).

By the Oligocene ocean temperatures had cooled to near modern levels and the taxa preserved here as fossils bear a strong resemblance to those found living beneath the Strait of Juan de Fuca today. Gastropods, bivalves, echinoids, coral, chitin and limpets are common-ish — and on rare occasions, fossil marine mammals, cetacean and bird bones are discovered.

Fossil Bird Bones 

Back in 2013, Steve Suntok and his family found fossilized bones from a 25-million-year-old wing-propelled flightless diving bird while out strolling the shoreline near Sooke. Not knowing what they had found but recognizing it as significant, the bones were brought to the Royal British Columbia Museum to identify.

The bones found their way into the hands of Gary Kaiser. Kaiser worked as a biologist for Environment Canada and the Nature Conservatory of Canada. After retirement, he turned his eye from our extant avian friends to their fossil lineage. The thing about passion is it never retires. Gary is now a research associate with the Royal British Columbia Museum, published author and continues his research on birds and their paleontological past.

Kaiser identified the well-preserved coracoid bones as the first example from Canada of a Plotopteridae, an extinct family that lived in the North Pacific from the late Eocene to the early Miocene. In honour of the First Nations who have lived in the area since time immemorial and Steve Suntok who found the fossil, Kaiser named the new genus and species Stemec suntokum.

Magellanic Penguin Chick, Spheniscus magellanicus

This is a very special find. Avian fossils from the Sooke Formation are rare. We are especially lucky that the bird bone was fossilized at all.  These are delicate bones and tasty. Scavengers often get to them well before they have a chance and the right conditions to fossilize.

Doubly lucky is that the find was of a coracoid, a bone from the shoulder that provides information on how this bird moved and dove through the water similar to a penguin. It's the wee bit that flexes as the bird moves his wing up and down.

Picture a penguin doing a little waddle and flapping their flipper-like wings getting ready to hop near and dive into the water. Now imagine them expertly porpoising —  gracefully jumping out of the sea and zigzagging through the ocean to avoid predators. It is likely that the Sooke find did some if not all of these activities.

When preservation conditions are kind and we are lucky enough to find the forelimbs of our plotopterid friends, their bones tell us that these water birds used wing-propelled propulsion to move through the water similar to penguins (Hasegawa et al., 1979; Olson and Hasegawa, 1979, 1996; Olson, 1980; Kimura et al., 1998; Mayr, 2005; Sakurai et al., 2008; Dyke et al., 2011).

Kaiser published on the find, along with Junya Watanabe, and Marji Johns. Their work: "A new member of the family Plotopteridae (Aves) from the late Oligocene of British Columbia, Canada," can be found in the November 2015 edition of Palaeontologia Electronica. If you fancy a read, I've included the link below.

The paper shares insights into what we have learned from the coracoid bone from the holotype Stemec suntokum specimen. It has an unusually narrow, conical shaft, much more gracile than the broad, flattened coracoids of other avian groups. This observation has led some to question if it is, in fact, a proto-cormorant of some kind. We'll need to find more of their fossilized lineage to make any additional comparisons.

Sooke, British Columbia and Juan de Fuca Strait

Today, fossils from these flightless birds have been found in outcrops in the United States and Japan (Olson and Hasegawa, 1996). They are bigger than the Sooke specimens, often growing up to two metres.

While we'll never know for sure, the wee fellow from the Sooke Formation was likely about 50-65 cm long and weighed in around 1.72-2.2 kg — so roughly the length of a duck and weight of a small Magellanic Penguin, Spheniscus magellanicus, chick. 

To give you a visual, I have included a photo of one of these cuties here showing off his full range of motion and calling common in so many young.

The first fossil described as a Plotopteridae was from a wee piece of the omal end of a coracoid from Oligocene outcrops of the Pyramid Hill Sand Member, Jewett Sand Formation of California (LACM 8927). Hildegarde Howard (1969) an American avian palaeontologist described it as Plotopterum joaquinensis. Hildegarde also did some fine work in the La Brea Tar Pits, particularly her work on the Rancho La Brea eagles.

In 1894, a portion of a pelagornithid tarsometatarsus, a lower leg bone from Cyphornis magnus (Cope, 1894) was found in Carmanah Group on southwestern Vancouver Island (Wetmore, 1928) and is now in the collections of the National Museum of Canada as P-189401/6323. This is the wee bone we find in the lower leg of birds and some dinosaurs. We also see this same bony feature in our Heterodontosauridae, a family of early and adorably tiny ornithischian dinosaurs — a lovely example of parallel evolution.

While rare, more bird bones have been found in the Sooke Formation over the past decade. In 2013, three avian bones were found in a single year. The first two were identified as possibly being from a cormorant and tentatively identified as Phalacrocoracidae tibiotarsi, the large bone between the femur and the tarsometatarsus in the leg of a bird.

They are now in the collections of the Royal BC Museum as (RBCM.EH2013.033.0001.001 and RBCM.EH2013.035.0001.001). These bones do have the look of our extant cormorant friends but the specimens themselves were not very well-preserved so a positive ID is tricky.

The third (and clearly not last) bone, is a well-preserved coracoid bone now in the collection at the RBCM as (RBCM.EH2014.032.0001.001).

The fossil bird find was the first significant find by the Suntok family but not their last. Just last year, they found part of a fish dental plate was studied by Russian researcher Evgeny Popov who named this new genus and species of prehistoric fish Canadodus suntoki, which translates to the "Tooth from Canada." Perhaps not quite as inspired as Kaiser, but a lovely homage to these Citizen Scientists.

Sooke Fossil Fauna

Along with these rare bird bones, the Paleogene sedimentary deposits of the Carmanah Group on southwestern Vancouver Island have a wonderful diversity of delicate fossil molluscs (Clark and Arnold, 1923). Walking along the beach, look for boulders with white shelly material in them. You'll want to collect from the large fossiliferous blocks and avoid the cliffs. The lines of fossils you see in those cliffs tell the story of deposition along a strandline. Collecting from them is both unsafe and poor form as it disturbs nearby neighbours and is discouraged.

Sooke Formation Gastropods, Photo: John Fam

We find nearshore and intertidal genera such as Mytilus (mussels) and barnacles, as well as more typically subtidal predatory globular moon snails (my personal favourite), surf clams (Spisula, Macoma), and thin, flattened Tellin clams.

The preservation here formed masses of shell coquinas that cemented together but are easily worked with a hammer and chisel. Remember your eye protection and I'd choose wellies or rubber boots over runners or hikers.

You may be especially lucky on your day out. Look for the larger fossil bones of marine mammals and whales that lived along the North American Pacific Coast in the Early Oligocene (Chattian).

Concretions and coquinas on the beach have yielded desmostylid, an extinct herbivorous marine mammal, Cornwallius sookensis (Cornwall, 1922) and 40 cm. skull of a cetacean Chonecetus sookensis (Russell, 1968), and a funnel whale, a primitive ancestor of our Baleen whales. 

A partial lower jaw and molar possibly from a large, bear-like beach-dwelling carnivore, Kolponomos, was also found here. A lovely skull from a specimen of Kolponomos clallamensis (Stirton, 1960) was found 60 km southwest across the Strait of Juan de Fuca in the early Miocene Clallam Formation and published by Lawrence Barnes and James Goedert. That specimen now calls the Natural History Museum of Los Angeles County home and is in their collections as #131148.

Directions to Muir Creek Fossil Site at Sooke: 

From the town of Sooke west of Victoria, follow Highway 14 for about 14 kilometres. Just past the spot where the highway crosses Muir Creek, you will see a gravel parking area on your left. Pull in and park here. 

From the barrier, walk out to the beach and turn right (west) and walk until you see the low yellow-brown sandstone cliffs about 400 metres ahead. 

Look at the grey sandstone boulders on the beach with bits of white flecks in them. The fossil material here will most often be a whitish cream colour. Check for low tide before heading out and choose rubber boots for this beach adventure.

References: 

L. S. Russell. 1968. A new cetacean from the Oligocene Sooke Formation of Vancouver Island, British Colombia. Canadian Journal of Earth Science 5:929-933
Barnes, Lawrence & Goedert, James. (1996). Marine vertebrate palaeontology on the Olympic Peninsula. Washington Geology, 24(3):17-25.

Fancy a read? Here's the link to Gary Kaiser's paper: https://palaeo-electronica.org/content/2015/1359-plotopterid-in-canada. If you'd like to head to the beach site, head to: 48.4°N 123.9°W, paleo-coordinates 48.0°N 115.0°W.

FRACTAL BUILDING: AMMONITES

Argonauticeras besairei, Collection of José Juárez Ruiz.

An exceptional example of fractal building of an ammonite septum, in this clytoceratid Argonauticeras besairei from the awesome José Juárez Ruiz.

Ammonites were predatory, squid-like creatures that lived inside coil-shaped shells.

Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. They used these tentacles to snare prey, — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunt today.

Catching a fish with your hands is no easy feat, as I'm sure you know. But the Ammonites were skilled and successful hunters. They caught their prey while swimming and floating in the water column. Within their shells, they had a number of chambers, called septa, filled with gas or fluid that were interconnected by a wee air tube. By pushing air in or out, they were able to control their buoyancy in the water column.

They lived in the last chamber of their shells, continuously building new shell material as they grew. As each new chamber was added, the squid-like body of the ammonite would move down to occupy the final outside chamber.

They were a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids — octopuses, squid, and cuttlefish) than they are to shelled nautiloids such as the living Nautilus species.

The Ammonoidea can be divided into six orders:

• Agoniatitida, Lower Devonian - Middle Devonian
• Clymeniida, Upper Devonian
• Goniatitida, Middle Devonian - Upper Permian
• Prolecanitida, Upper Devonian - Upper Triassic
• Ceratitida, Upper Permian - Upper Triassic
• Ammonitida, Lower Jurassic - Upper Cretaceous

Ammonites have intricate and complex patterns on their shells called sutures. The suture patterns differ across species and tell us what time period the ammonite is from. If they are geometric with numerous undivided lobes and saddles and eight lobes around the conch, we refer to their pattern as goniatitic, a characteristic of Paleozoic ammonites.

If they are ceratitic with lobes that have subdivided tips; giving them a saw-toothed appearance and rounded undivided saddles, they are likely Triassic. For some lovely Triassic ammonites, take a look at the specimens that come out of Hallstatt, Austria and from the outcrops in the Humboldt Mountains of Nevada.

Hoplites bennettiana (Sowby, 1826).

If they have lobes and saddles that are fluted, with rounded subdivisions instead of saw-toothed, they are likely Jurassic or Cretaceous. If you'd like to see a particularly beautiful Lower Jurassic ammonite, take a peek at Apodoceras. Wonderful ridging in that species.

One of my favourite Cretaceous ammonites is the ammonite, Hoplites bennettiana (Sowby, 1826). This beauty is from Albian deposits near Carrière de Courcelles, Villemoyenne, near la région de Troyes (Aube) Champagne in northeastern France.

At the time that this fellow was swimming in our oceans, ankylosaurs were strolling about Mongolia and stomping through the foliage in Utah, Kansas and Texas. Bony fish were swimming over what would become the strata making up Canada, the Czech Republic and Australia. Cartilaginous fish were prowling the western interior seaway of North America and a strange extinct herbivorous mammal, Eobaatar, was snuffling through Mongolia, Spain and England.

In some classifications, these are left as suborders, included in only three orders: Goniatitida, Ceratitida, and Ammonitida. Once you get to know them, ammonites in their various shapes and suturing patterns make it much easier to date an ammonite and the rock formation where is was found at a glance.

Ammonites first appeared about 240 million years ago, though they descended from straight-shelled cephalopods called bacrites that date back to the Devonian, about 415 million years ago, and the last species vanished in the Cretaceous–Paleogene extinction event.

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.

References: Inoue, S., Kondo, S. Suture pattern formation in ammonites and the unknown rear mantle structure. Sci Rep 6, 33689 (2016). https://doi.org/10.1038/srep33689
https://www.nature.com/articles/srep33689?fbclid=IwAR1BhBrDqhv8LDjqF60EXdfLR7wPE4zDivwGORTUEgCd2GghD5W7KOfg6Co#citeas

Photo: Hoplites Bennettiana from near Troyes, France. Collection de Christophe Marot