FOSSIL HUNTRESS
MUSINGS MEANT TO CAPTIVATE, EDUCATE AND INSPIRE
Friday, 15 November 2024
FOSSIL SITES OF THE OKANAGAN HIGHLANDS
Thursday, 14 November 2024
SPINY HETEROMORPH: AMMONITE INDEX FOSSILS
Sunday, 10 November 2024
HERMIT CRAB: REAL ESTATE TYCOONS OF THE FORESHORE
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.
Wednesday, 6 November 2024
LIVING FOSSILS: MASTERS OF MASS EXTINCTION EVENTS
Much like (slow) Water Striders (Aquarius remigis), (relatively sluggish) Coelacanth (Latimeria chalumnae) and (the current winner on really slow evolution) Elephant Sharks (Callorhinchus milii), these fellows have a long history in the fossil record with very few anatomical changes.
But slow change provides loads of great information. It makes our new friend, Yunnanolimulus luoingensis, an especially interesting and excellent reference point for how this group evolved.
We can examine their genome today and make comparisons all the way back to the Middle Triassic (with this new find) and other specimens from further back in the Ordovician — 445 million years ago.
These living fossils have survived all five mass extinction events. They are generalists who can live in shallow or deep water and will eat pretty much anything they can find on the seafloor.
The oldest horseshoe crab fossil, Lunataspis aurora, is found in outcrops in Manitoba, Canada. Charmingly, the name means crescent moon shield of the dawn. It was palaeontologist Dave Rudkin and team who chose that romantic name. Finding them as fossils is quite remarkable as their shells are made of protein which does not mineralized like typical fossils.
Even so, the evolution of their exoskeleton is well-documented by fossils, but appendage and soft-tissue preservation are extremely rare.
A new study analyzes details of the appendage and soft-tissue preservation in Yunnanolimulus luoingensis, a Middle Triassic (ca. 244 million years old) horseshoe crab from Yunnan Province, SW China. The remarkable anatomical preservation includes the chelicerae, five pairs of walking appendages, opisthosomal appendages with book gills, muscles, and fine setae permits comparison with extant horseshoe crabs.
The occurrence of Carcinoscorpius-type claspers on the first and second walking legs in male individuals of Y. luoingensis tells us that simple chelate claspers in males are plesiomorphic for horseshoe crabs, and the bulbous claspers in Tachypleus and Limulus are derived.
As an aside, if you hadn't seen an elephant shark before and were shown a photo, you would likely say, "that's no freaking shark." You would be wrong, of course, but it would be a very clever observation.
Callorhinchus milii look nothing like our Great White friends and they are not true sharks at all. Rather, they are ghost sharks that belong to the subclass Holocephali (chimaera), a group lovingly known as ratfish. They diverged from the shark lineage about 400 million years ago.
If you have a moment, do a search for Callorhinchus milii. The odd-looking fellow with the ironic name, kallos, which means beautiful in Greek, sports black blotches on a pale silver elongate body. And their special feature? It is the fishy equivalent of business in the front, party in the back, with a dangling trunk-like projection at the tip of their snout and well-developed rectal glands near the tail.
As another small point of interest with regards to horseshoe crabs, John McAllister collected several of these while working on his MSc to see if they had microstructures similar to trilobites (they do) and whether their cuticles were likewise calcified. He found no real calcification in their cuticles, in fact, he had a rather frustrating time getting anything measurable to dissolve in acid in his hunt for trace elements.
Likewise, when looking at oxygen isotopes (16/18) to get a handle on water salinity and temperature, his contacts at the University of Waterloo had tons of fun getting anything at all to analyze. It made for some interesting findings. Sadly, for a number of reasons, he abandoned the work, but you can read his very interesting thesis here: https://dr.library.brocku.ca/handle/10464/1959
Ref: Hu, Shixue & Zhang, Qiyue & Feldmann, Rodney & Benton, Michael & Schweitzer, Carrie & Huang, Jinyuan & Wen, Wen & Zhou, Changyong & Xie, Tao & Lü, Tao & Hong, Shuigen. (2017). Exceptional appendage and soft-tissue preservation in a Middle Triassic horseshoe crab from SW China. Scientific Reports. 7. 10.1038/s41598-017-13319-x.
Tuesday, 5 November 2024
CTENOPHORES: COMB JELLIES
Cannibalistic Comb Jellies |
Ctenophores or comb jellies are one of the phylogenetically most important and controversial metazoan groups. They are not jellyfish and are not closely related, though they do share some characteristics with the gelatinous members of the subphylum Medusozoa.
Comb jellies are not picky eaters. Their tastes range to what is at hand, including cannibalizing other comb jellies. They will feast on their kin along with tasty plankton, zooplankton, crustaceans and wee fish.
Interest in their fossil record has been catalysed by spectacularly preserved soft-bodied specimens from Cambrian Lagerstätten of the 518-million-years-old Chengjiang Biota, the 505-million-years-old Burgess Shale and other Burgess Shale-like deposits.
We find them in the Late Devonian Escuminac Formation at Miguasha National Park, Quebec, Canada — a UNESCO world heritage site famous for its abundance of well-preserved vertebrate fossils including most major evolutionary groups of Devonian lower vertebrates from jawless fish to stem-tetrapods.
Based on morphological similarities of this Canadian fossil with stem-ctenophore fossils from the Cambrian Lagerstätte of the Chinese locality Chengjiang, they have been assessed for their affinity to stem-group ctenophores (dinomischids, Siphusauctum, scleroctenophorans) and early crown-group ctenophores. Modern ctenophores and many fossil forms lack mineralized hard parts, which renders the rare fossils that have been extracted from several Lagerstätten quite remarkable.
Like the soft bodies of jellyfish and the polyps of hydrozoans and anthozoans, the probability for such soft bodies (or body regions) to become fossilized is extremely low. In spite of this low preservation potential, remains of stem-ctenophores have become known from several Cambrian and younger conservation deposits, and with even older candidate ctenophores in the Ediacaran.
While Cambrian Lagerstätten have yielded several genera, ctenophore remains are much rarer in the Devonian; in particular, two studies, describing material from the German Hunsrück Slate.
Bioluminescent Comb Jellies |
The most basal stem ctenophores are the dinomischids: sessile benthic petaloid invertebrates, many of which are equipped with a stalk. This group first was described from the Middle Cambrian Burgess Shale. Based on the genus Dinomischus, these early stalked forms were commonly called ‘dinomischids’.
Zhao et al. shared that dinomischids "form a grade in the lower part of the ctenophore stem group” and include taxa such as Xianguangia, Daihua, and Dinomischus that have hexaradiate-based symmetry (e.g., sixfold, 18-fold).
Some later, skeletonised stem-ctenophores were termed ‘Scleroctenophora’; ‘scleroctenophorans’ have a shorter stalk, lack the ‘petals’ and have no bracts and might be monophyletic.
To date, all known dinomischids and scleroctenophorans are Cambrian. Remarkably, analysis of the material described here suggests it is a very late-surviving member of this part of the ctenophore tree, occurring in strata over a hundred million years younger with no intervening known record, thus making it a Lazarus taxon with an extensive ghost lineage.
Palaeozoic sediments yield a growing number of fossil invertebrates with radial symmetries, some being quite enigmatic with body plans differing radically from those of extant organisms.
The morphological similarities to Cambrian forms and the mix of characters regarding overall shape and symmetries render this discovery important. The aims of this study are to describe the only known specimen of this Devonian ctenophore, discuss its phylogenetic and systematic position, and the impact of fossil data for ctenophore affinities, and assess its palaeoecological role.
Saturday, 2 November 2024
HAIDA GWAII: ISLANDS OF MIST
They form part of Wrangellia, an exotic tectonostratigraphic terrane that includes Vancouver Island, parts western British Columbia and Alaska.
The Geological Survey of Canada 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.
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.
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 had planned this expedition as part of our “trips of a lifetime.”
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.
Douvelliceras spiniferum, Cretaceous Haida Formation |
Missing from this trip log are tales of Rene Savenye, who passed away in the weeks just prior. 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.
The genus Douvilleiceras range from Middle to Late Cretaceous and can be found in Asia, Africa, Europe and North and South America.
Friday, 1 November 2024
GRAY WHALES: ESCHRICHTIUS ROBUSTUS
Young Gray Whale, Eschrichtius robustus |
Two Pacific Ocean populations are known to exist: one of about 200 individuals whose migratory route is presumed to be between the Sea of Okhotsk off Russia's south coast and southern Korea, and a larger one with a population of about 27,000 individuals in the eastern Pacific.
This second group are the ones we see off the shores of British Columbia as they travel the waters from northernmost Alaska down to Baja California. Gray whale mothers make this journey accompanied by their calves, hugging the shore in shallow kelp beds and providing rare but welcome glimpses of this beauty.
The gray whale is traditionally placed as the only living species in its genus and family, Eschrichtius and Eschrichtiidae, but an extinct species was discovered and placed in the genus in 2017 — the Akishima whale, E. akishimaensis. Some recent DNA analyses suggest that certain rorquals of the family Balaenopteridae, such as the humpback whale, Megaptera novaeangliae, and fin whale, Balaenoptera physalus, are more closely related to the gray whale than they are to some other rorquals, such as minke. Still, others place gray whales as outside the rorqual clade, a kissing cousin if you will.
John Edward Gray placed it in its own genus in 1865, naming it in honour of physician and zoologist Daniel Frederik Eschricht. The common name of the whale comes from its colouration. The subfossil remains of now-extinct gray whales from the Atlantic coasts of England and Sweden were used by Gray to make the first scientific description of a species then surviving only in Pacific waters. The living Pacific species was described by American palaeontologist, Edward Drinker Cope as Rhachianectes glaucus in 1869.
Fin Whale, Balaenoptera physalus |
In 1993, a twenty-seven million-year-old specimen was discovered in deposits in Washington state that represents a new species of early baleen whale. It is especially interesting as it is from a stage in the group’s evolutionary history when baleen whales transitioned from having teeth to filtering food with baleen bristles.
Visiting researcher Carlos Mauricio Peredo studied the fossil whale remains, publishing his research to solidify Sitsqwayk cornishorum (pronounced sits-quake) in the annals of history. The earliest baleen whales clearly had teeth, and clearly still used them. Modern baleen whales have no teeth and have instead evolved baleen plates for filter feeding. Look to the rather good close-up of this young Gray Whale here to see his baleen where once there was a toothy grin.
The baleen is the comb-like strainer that sits on the upper jaw of baleen whales and is used to filter food. We have to ponder when this evolutionary change —moving from teeth to baleen — occurred and what factors might have caused it. Traditionally, we have sought answers about the evolution of baleen whales by turning to two extinct groups: the aetiocetids and the eomysticetids.
The aetiocetids are small baleen whales that still have teeth, but they are very small, and it remains uncertain whether or not they used their teeth. In contrast, the eomysticetids are about the size of an adult Minke Whale and seem to have been much more akin to modern baleen whales; though it’s not certain if they had baleen. Baleen typically does not preserve in the fossil record being soft tissue; generally, only hard tissue, bones and teeth are fossilized.
SHONISAURUS OF NEVADA
The first researcher to recognize the Nevada fossil specimens as ichthyosaurs was Siemon W. Muller of Stanford University. He had the work of Sir Richard Owen and others to build on. That being said, there are very few contenders for a species that boasts vertebrae over a foot wide and weighing in at almost 10 kg or 21 lbs. Muller contacted the University of California Museum of Paleontology at Berkeley. Surface collecting by locals continued at the site but no major excavation was planned.
Sir Richard Owen, the British biologist, comparative anatomist and paleontologist, coined the name ichthyopterygia, or "fish flippers," one hundred and fourteen years earlier, but that wee bit of scientific knowledge hadn't made its way west to the general population. The finds at Luning were still, "marine monsters."
Owen, too, was building on research going back to 1699, the very first recorded fossil fragments found of these beasties in Wales. Shortly thereafter, fossil vertebrae were published in 1708 from the Lower Jurassic.
The first complete skeleton was discovered in the early 19th century by Mary Anning and her brother Joseph along the Dorset Jurassic Coast. Mary's find was described by a British surgeon, Sir Everard Home, an elected Fellow of the Royal Society, in 1814. The specimen is now on display at the Natural History Museum in London bearing the name Temnodontosaurus platyodon, or “cutting-tooth lizard.”
In 1821, William Conybeare and Henry De La Beche, a friend of Mary's, published a paper describing three new species of unknown marine reptiles based on the Anning's finds. The Rev. William Buckland would go on to describe two small ichthyosaurs from the Lias of Lyme Regis, Ichthyosaurus communis and Ichthyosaurus intermedius. All of this early work was instrumental in aiding the researchers who would join the project at Luning.
Owen is considered to have been an outstanding naturalist with a remarkable gift for interpreting fossils. Contrary to common belief, advanced study does help with identifying fossils, but what is truly needed is a keen eye. The finds at Luning were blessed to be seen by an enthusiastic local with just that right kind of keen eye.
Almost a quarter of a century after Muller's initial reports, Dr. Charles L. Camp from UCMP received correspondence further detailing the finds from a lovely Mrs. Margaret Wheat of Fallon. She wrote to Camp in September of 1928 to say that she'd been giving the quarry section a bit of a sweep, as you do, and had uncovered a nice aligned section of vertebrae with her broom. The following year, Dr. Charles L. Camp went out to survey the finds and began working on the specimens, his first field season of many, in 1954.
Back in the 1950s, these large marine reptiles were rumoured to be "marine monsters," as the concept of an ichthyosaur was not well understood by the local townsfolk. Excitement soon hit West Union Canyon as the quarry began to reveal the sheer size of these mighty beasts. Four of the specimens were fully excavated. Most of the ichthyosaur bones were left in situ, partially because the work was tremendously difficult, and partially to allow others to see how the specimens were laid down over 200 million years ago.
Camp continued to work with Wheat at the site and brought on Sam Welles and a host of students to help with excavations. The team understood the need for protection at the site. They canvassed the Nevada Legislature to establish the Ichthyosaur Paleontological State Monument. You can see one of the Park Rangers above giving a tour within the lovely Fossil Hut building they built on the site to protect the fossils.
In 1957, the site was incorporated into the State Park System and Berlin-Ichthyosaur State Park was born. The park Twenty years later, in 1977, the population of Nevada weighed in and the Legislature designated Shonisaurus popularis as the State Fossil of Nevada. Visitors are welcome to collect fossils from the exposures of the Upper Triassic (Early Norian, Kerri Zone) of the Luning Formation, West Union Canyon, just outside Berlin-Ichthyosaur State Park.
Address: State route 844, Austin, NV 89310, United States. Area: 4.58 km². Open 24 hours;
Elevation: 6,975 ft (2,126 m); Tel: +1 775-964-2440; http://parks.nv.gov/parks/berlin-ichthyosaur
Wednesday, 30 October 2024
NOOTKA: FOSSILS AND FIRST NATIONS HISTORY
Nootka Fossil Field Trip. Photo: John Fam |
Just off the shores of Vancouver Island, east of Gold River and south of Tahsis is the picturesque and remote Nootka Island.
This is the land of the proud and thriving Nuu-chah-nulth First Nations who have lived here always.
Always is a long time, but we know from oral history and archaeological evidence that the Mowachaht and Muchalaht peoples lived here, along with many others, for many thousands of years — a time span much like always.
While we know this area as Nootka Sound and the land we explore for fossils as Nootka Island, these names stem from a wee misunderstanding.
Just four years after the 1774 visit by Spanish explorer Juan Pérez — and only a year before the Spanish established a military and fur trading post on the site of Yuquot — the Nuu-chah-nulth met the Englishman, James Cook.
Captain Cook sailed to the village of Yuquot just west of Vancouver Island to a very warm welcome. He and his crew stayed on for a month of storytelling, trading and ship repairs. Friendly, but not familiar with the local language, he misunderstood the name for both the people and land to be Nootka. In actual fact, Nootka means, go around, go around.
Two hundred years later, in 1978, the Nuu-chah-nulth chose the collective term Nuu-chah-nulth — nuučaan̓uł, meaning all along the mountains and sea or along the outside (of Vancouver Island) — to describe themselves.It is a term now used to describe several First Nations people living along western Vancouver Island, British Columbia.
It is similar in a way to the use of the United Kingdom to refer to the lands of England, Scotland and Wales — though using United Kingdom-ers would be odd. Bless the Nuu-chah-nulth for their grace in choosing this collective name.
An older term for this group of peoples was Aht, which means people in their language and is a component in all the names of their subgroups, and of some locations — Yuquot, Mowachaht, Kyuquot, Opitsaht. While collectively, they are the Nuu-chah-nulth, be interested in their more regional name should you meet them.
But why does it matter? If you have ever mistakenly referred to someone from New Zealand as an Aussie or someone from Scotland as English, you have likely been schooled by an immediate — sometimes forceful, sometimes gracious — correction of your ways. The best answer to why it matters is because it matters.
Each of the subgroups of the Nuu-chah-nulth viewed their lands and seasonal migration within them (though not outside of them) from a viewpoint of inside and outside. Kla'a or outside is the term for their coastal environment and hilstis for their inside or inland environment.
It is to their kla'a that I was most keen to explore. Here, the lovely Late Eocene and Early Miocene exposures offer up fossil crab, mostly the species Raninid, along with fossil gastropods, bivalves, pine cones and spectacularly — a singular seed pod. These wonderfully preserved specimens are found in concretion along the foreshore where time and tide erode them out each year.
Five years after Spanish explorer Juan Pérez's first visit, the Spanish built and maintained a military post at Yuquot where they tore down the local houses to build their own structures and set up what would become a significant fur trade port for the Northwest Coast — with the local Chief Maquinna's blessing and his warriors acting as middlemen to other First Nations.
Following reports of Cook's exploration British traders began to use the harbour of Nootka (Friendly Cove) as a base for a promising trade with China in sea-otter pelts but became embroiled with the Spanish who claimed (albeit erroneously) sovereignty over the Pacific Ocean.
Dan Bowen searching an outcrop. Photo: John Fam |
George Vancouver on his subsequent exploration in 1792 circumnavigated the island and charted much of the coastline. His meeting with the Spanish captain Bodega y Quadra at Nootka was friendly but did not accomplish the expected formal ceding of land by the Spanish to the British.
It resulted however in his vain naming the island "Vancouver and Quadra." The Spanish captain's name was later dropped and given to the island on the east side of Discovery Strait. Again, another vain and unearned title that persists to this day.
Early settlement of the island was carried out mainly under the sponsorship of the Hudson's Bay Company whose lease from the Crown amounted to 7 shillings per year — that's roughly equal to £100.00 or $174 CDN today. Victoria, the capital of British Columbia, was founded in 1843 as Fort Victoria on the southern end of Vancouver Island by the Hudson's Bay Company's Chief Factor, Sir James Douglas.
With Douglas's help, the Hudson's Bay Company established Fort Rupert on the north end of Vancouver Island in 1849. Both became centres of fur trade and trade between First Nations and solidified the Hudson's Bay Company's trading monopoly in the Pacific Northwest.The settlement of Fort Victoria on the southern tip of Vancouver Island — handily south of the 49th parallel — greatly aided British negotiators to retain all of the islands when a line was finally set to mark the northern boundary of the United States with the signing of the Oregon Boundary Treaty of 1846. Vancouver Island became a separate British colony in 1858. British Columbia, exclusive of the island, was made a colony in 1858 and in 1866 the two colonies were joined into one — becoming a province of Canada in 1871 with Victoria as the capital.
Dan Bowen, Chair of the Vancouver Island Palaeontological Society (VIPS) did a truly splendid talk on the Fossils of Nootka Sound. With his permission, I have uploaded the talk to the ARCHEA YouTube Channel for all to enjoy. Do take a boo, he is a great presenter. Dan also graciously provided the photos you see here. The last of the photos you see here is from the August 2021 Nootka Fossil Field Trip. Photo: John Fam, Vice-Chair, Vancouver Paleontological Society (VanPS).
Know Before You Go — Nootka Trail
The Nootka Trail passes through the traditional lands of the Mowachaht/Muchalat First Nations who have lived here since always. They share this area with humpback and Gray whales, orcas, seals, sea lions, black bears, wolves, cougars, eagles, ravens, sea birds, river otters, insects and the many colourful intertidal creatures that you'll want to photograph.
This is a remote West Coast wilderness experience. Getting to Nootka Island requires some planning as you'll need to take a seaplane or water taxi to reach the trailhead. The trail takes 4-8 days to cover the 37 km year-round hike. The peak season is July to September. Permits are not required for the hike.
Access via: Air Nootka floatplane, water taxi, or MV Uchuck III
- Dan Bowen, VIPS on the Fossils of Nootka: https://youtu.be/rsewBFztxSY
- https://www.thecanadianencyclopedia.ca/en/article/sir-james-douglas
- file:///C:/Users/tosca/Downloads/186162-Article%20Text-199217-1-10-20151106.pdf
- Nootka Trip Planning: https://mbguiding.ca/nootka-trail-nootka-island/#overview
Tuesday, 29 October 2024
SAKARA MADAGASGAR: OXFORDIAN OUTCROPS
Ammonites were predatory, squidlike 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. Ammonites did the equivalent, catching prey in their tentacles. They 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) then they are to shelled nautiloids such as the living Nautilus species.
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.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.
Monday, 28 October 2024
SMILODON NORTH OF THE 49TH PARALLEL
Smilodon is a genus of the extinct machairodont subfamily of the felids. It is one of the most famous prehistoric mammals and the best known saber-toothed cat. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats.
Up until a few years ago, all the great fossil specimens of this apex predator were found south of us in the United States. That was until some interesting bones from Medicine Hat, Alberta got a second look.
A few years ago, a fossil specimen caught the eye of researcher Ashley Reynolds as she was rummaging through the collections at the Royal Ontario Museum in Toronto.
Back in the 1960s, University of Toronto palaeontologist C.S. Churcher and his team had collected and donated more than 1,200 specimens from their many field seasons scouring the bluffs of the South Saskatchewan River near Medicine Hat, Alberta.
Churcher is a delightful storyteller and a palaeontologist with a keen eye. I had the very great pleasure of listening to many of his talks out at the University of British Columbia and a few Vancouver Paleontological Society meetings in the mid-2000s.
"Rufus" was a thoroughly charming storyteller and shared many of his adventures from the field.
He moved out to the West Coast for his retirement, first to Gabriola Island then to Victoria, but his keen love of the science kept him giving talks to enthralled listeners keen to hear about his survey of the Dakhleh Oasis in the Western Desert of Egypt, geomorphology, stratigraphy, recent biology, Pleistocene and Holocene lithic cultures, insights learned from Neolithic Islamic pottery to Roman settlements.
The specimens he had collected had been roughly sorted but never examined in detail. Reynolds, who was researching the growth patterns and life histories of extinct cats saw a familiar-looking bone from an ancient cat's right front paw. That tiny paw bone had reached through time and was positively identified as Canada's first Smilodon.
These Apex Predators used their exceptionally long upper canine teeth to hunt large mammals.
Isotopes preserved in the bones of S. fatalis in the La Brea Tar Pits in California tell us that they liked to dine on bison (Bison antiquus) and camels (Camelops) along with deer and tapirs. Smilodon is thought to have killed its prey by holding it still with its forelimbs and biting it. And that was quite the bite!
Their razor-sharp incisors were arranged in an arch. Once they bit down, the teeth would hold their prey still and stabilize it while the canine bite was delivered — and what a bite that was. They could open their mouths a full 120 degrees.
Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species.
Sunday, 27 October 2024
BEARS OF THE PACIFIC NORTHWEST
If you work or play in the woods of British Columbia, both grizzly and black bear sightings are common.
Nearly half the world's population, some 25,000 Grizzly Bears, roam the Canadian wilderness — of those, 14,000 or more call British Columbia home. These highly intelligent omnivores spend their days lumbering along our coastlines, mountains and forests.
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 very large descendants.
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 in the hopes of finding a mate. Through adaptation to shifting seasons, the females' reproductive system delays the implantation of fertilized eggs — blastocysts —until November or December to ensure her healthy pups arrive during hibernation. If food resources were slim that year, the newly formed embryo will not catch or attach itself to her uterine wall and she'll try again next year.
Females 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. The cubs stay with their mamma for 18 months or more. Once fully grown, they can run 56 km an hour, are good at climbing trees and swimming and live 20-25 years in the wild.
First Nation Lore and Language
In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest — or Kwakwaka'wakw, speakers of Kwak'wala — a Grizzly bear is known as na̱n.
The ornamental carved Grizzly bear headdress was 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 were given supernatural treasures or dloogwi which they passed down from generation to generation.
In the Hamat'sa Grizzly bear dance, Nanes Bakbakwalanooksiwae, no mask was worn. Instead, the dancers painted their faces red and wore a costume of bearskin or t̓ła̱ntsa̱m and long wooden claws attached to their hands. You can imagine how impressive that sight is lit by the warm flickering flames of firelight during a Winter Dance ceremony.
Smoke of the World / Speaking of the Ancestors — Na̱wiła
Kwaguʼł Winter Dancers — Qagyuhl |
To tell stories of the ancestors is na̱wiła. Each of these ancestors took off their masks to become human and founded the many groups that are now bound together by language and culture as Kwakwaka’wakw.
The four First Nations who collectively make up the Kwakiutl are the Kwakiutl (Kwágu7lh), K’umk’utis/Komkiutis, Kwixa/Kweeha (Komoyoi) and Walas Kwakiutl (Lakwilala) First Nations.
There is likely blood of the Lawit’sis in there, too, as they inhabited the village site at Tsax̱is, Fort Rupert before the Kwakiutl made it a permanent home.
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.
Visiting British Columbia's Great Bears
If you are interested in viewing British Columbia's Great Bears, do check out Indigenous Tourism BC's wonderfully informative website and the culturally-rich wildlife experiences on offer.You will discover travel ideas and resources to plan your next soul-powered adventure. To learn more about British Columbia's Great Bears and the continuing legacy of First Nation stewardship, visit:
Indigenous Tourism BC: https://www.indigenousbc.com
Great Bear Lodge has been offering tours to view the majestic animals of the Pacific Northwest. They keep both the guests and the animals' comfort and protection in mind. I highly recommend their hospitality and expertise. To see their offerings, visit: www.greatbeartours.com
Image: Group of Winter Dancers--Qagyuhl; Curtis, Edward S., 1868-1952, https://lccn.loc.gov/2003652753.
Note: The Qagyuhl in the title of this photograph refers to the First Nation group, not the dancers themselves. I think our dear Edward was trying to spell Kwaguʼł and came as close as he was able. In Kwak'wala, the language of the Kwaguʼł or Kwakwakaʼwakw, speakers of Kwak'wala, the Head Winter Dancer is called t̕seḵa̱me' — and to call someone a really good dancer, you would use ya̱'winux̱w.
Charmingly, when Edward S. Curtis was visiting Tsaxis/T'sakis, he was challenged to a wrestling competition with a Giant Pacific Octopus, Enteroctopus dofleini. George Hunt (1854-1933) had issued the challenge and laughed himself senseless when Edward got himself completely wrapped up in tentacles and was unable to move. Edward was soon untangled and went on to take many more photos of the First Nations of the Pacific Northwest. Things did not go as well for the octopus or ta̱ḵ̕wa. It was later served for dinner or dzaḵwax̱stala, as it seemed calamari was destined for that night's menu.
Thursday, 24 October 2024
BRONZE BEAUTY: EIFELIAN PARALEJURUS
It was the colour of this amazing trilobite that captured the eye of David Appleton in whose collection it now resides. He is an avid collector and coming into his own as a macro photographer. I have shared three of his delightful photos for you here.
It initially thought that the gold we see here was added during prep, particularly considering the colouration of the matrix, but macro views of the surface show mineralization and the veins running right through the specimen into the matrix. There is certainly some repairs but that is common in the restoration of these specimens. Many of the trilobites I have seen from Morocco have bronze on black colouring but not usually this pronounced. Even so, there is a tremendous amount of fine anatomy to explore and enjoy in this wonderfully preserved specimen.
Paralejurus is a genus of trilobite in the phylum Arthropoda from the Late Silurian to the Middle Devonian of Africa and Europe. These lovelies grew to be up to nine centimetres, though the fellow you see here is a wee bit over half that size at 5.3 cm.
Paralejurus specimens are very pleasing to the eye with their long, oval outline and arched exoskeletons.
Their cephalon or head is a domed half circle with a smooth surface. The large facet eyes have very pleasing crescent-shaped lids. You can see this rather well in the first of the photos here. The detail is quite remarkable.
As you move down from his head towards the body, there is an almost inconspicuous occipital bone behind the glabella in the transition to his burnt bronze thorax.
The body or thorax has ten narrow segments with a clearly arched and broad axial lobe or rhachis. The pygidium is broad, smooth and strongly fused in contrast to the genus Scutellum in the family Styginidae, which has a pygidium with very attractive distinct furrows that I liken to the look of icing ridges on something sweet — though that may just be me and my sweet tooth talking. In Paralejurus, they look distinctly fused — or able to fuse — to add posterior protection against predators with both the look and function of Roman armour.
In Paralejurus, the axillary lobe is rounded off and arched upwards. It is here that twelve to fourteen fine furrows extend radially to complete the poetry of his body design.
Trilobites were amongst the earliest fossils with hard skeletons and they come in many beautiful forms. While they are extinct today, they were the dominant life form at the beginning of the Cambrian.As a whole, they were amongst some of the most successful of all early animals — thriving and diversifying in our ancient oceans for almost 300 million years. The last of their brethren disappeared at the end of the Permian — 252 million years ago. Now, we enjoy their beauty and the scientific mysteries they reveal about our Earth's ancient history.
Photos and collection of the deeply awesome David Appleton. Specimen: 5.3 cm.
Tuesday, 22 October 2024
TRACKING THROUGH THE TRIASSIC
Grambergia sp. Middle Triassic Ammonoid of BC, Canada |
Lower and upper Triassic faunas of these areas, as well as some that are today up to 63 ° North, have the characteristics of the lower palaeo latitudes.
A distinction between the provinces of the middle and the higher palaeo-situations can not be made for the lower Triassic and lower Middle Triassic (anise). However, all three provinces can be seen in the deposits of Ladin, Kam and Nor.
In the early 2000s, as part of a series of joint UBC, VIPS and VanPS fossil field trips (and then Chair of the VanPS), I explored much of the lower faunal outcrops of northeastern British Columbia. It was my first time seeing many of British Columbia's Triassic outcrops.
Triassic ammonoids, West Humboldt Mountains, Nevada, USA |
Aside from sheer beauty and spectacular preservation, the ammonoids and belemnites were tucked in cozily with very well preserved ichthyosaur remains.
Tozer's interest in our marine invert friends was their distribution. How and when did certain species migrate, cluster, evolve — and for those that were prolific, how could their occurrence — and therefore significance — aide in an assessment of plate and terrane movements that would help us to determine paleolatitudinal significance.
Middle Triassic (Anisian/Ladinian) Fauna |
N. J. Siberling from the US Geological Survey published on these same Nevada outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species. Both their works would inform what would become a lifelong piecing together of the Triassic puzzle for Tozer.
The terranes that now form the western Cordillera were probably welded together and reached the North American plate before the end of the Jurassic period.
Marine Triassic occurs on the North American Plate over a latitudinal spread of 46 degrees, from California to Ellesmere Island. At some intervals of time faunas on the Plate permit the discrimination of two or three provinces with distinctively different coeval faunas.
Juvavites sp. Geological Survey of Canada. Photo: John Fam |
Lower and Upper Triassic faunas from these terranes, including some which today are at 63 degrees north, have the characters of the LPL province.
Middle Triassic faunas from the terranes, as presently known, do not contribute significant data. In the terranes of the Western Cordillera, LPL faunas were now up to 3,000 km north of their counterparts on the American Plate. Through the fossil fauna assemblages, we can see this level of tectonic displacement.
Taking into account the faunas and the nature of the rocks, the Triassic paleogeography is interpreted as a tectonically quiet west shore for the North American Plate, bordered by an open sea or ocean; then, well off-shore, a series of volcanic archipelagos shedding sediment into adjacent basins. Some were fringed or intermittently covered by coralline shoals and carbonate banks. Deeper basins were in between. The islands probably were within 30 degrees of the Triassic equator and extended offshore for about 5000 km, to the spreading ridge directly ancestral to the East Pacific Rise. The geography west of the spreading ridge was probably comparable.
At the end of the Rhaetian (part of the Triassic period), most of the ammonites had died out. These are the lovely coiled molluscs you often see in museums and gift shops that sell fossils. They are a particular favourite of mine and they are both beautiful and useful to tell us much about deep time. The Hettangian, a rather poorly understood 3 million year time interval followed the Triassic-Jurassic mass extinction event.
During the Hettangian, the new or Neoammonites developed quite quickly. Within a million years, a fairly large, diverse selection of genera and species had risen to fill the void. The gap created by the Triassic-Jurassic extinction event was re-filled and our ability to "read the rocks' to understand their continued movement through tectonic plate shifting recommenced.
Alsatites proaries, Hettangian Ammonite |
This Hettangian ammonite, Alsatites proaries, is a lovely example of the cephalopods cruising our ancient oceans at that time. Alsatites is an extinct genus of cephalopod belonging to the Ammonite subclass. They lived during the Early Jurassic, Hettangian till the Sinemurian and are generally extremely evolute, many whorled with a broad keel. Or, as described by one of my very young friends, he looks like a coiled snake you make in pottery class.
The Hettangian is an interesting little period of our history. It spans the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma (million years ago). For my European friends, the Hettangian is the time in which the marine limestone, shales and clay Lias of western Europe were deposited. In British Columbia, Canada, we see the most diverse middle and late Hettangian (Early Jurassic) ammonite assemblages in the Queen Charlotte Islands (Haida Gwaii), an archipelago about 50 km off British Columbia's northern Pacific coast. In total, 53 ammonite taxa are described of which Paradasyceras carteri, Franziceras kennecottense, Pleuroacanthites charlottensis, Ectocentrites pacificus and Curviceras haidae are new.
In general, North American Early Jurassic ammonites are of Tethyan affinity or endemic to the eastern Pacific. For this reason, a separate zonation for the Hettangian and Sinemurian of the Western Cordillera of North America was established. Taylor et al. (2001), wrote up and published on much of this early research though, at the time, very little Canadian information was included.
Longridge, L. M., et al. “Three New Species of the Hettangian (Early Jurassic) Ammonite Sunrisites from British Columbia, Canada.” Journal of Paleontology, vol. 82, no. 1, 2008, pp. 128–139. JSTOR, www.jstor.org/stable/20144175. Accessed 27 Jan. 2020.
Tozer, ET (Tim): Marine Triassic faunas of North America: Their significance for assessing plate and terrane movements. Geol Rundsch 71, 1077-1104 (1982). https://doi.org/10.1007/BF01821119
Danner, W. (Ted): Limestone resources of southwestern British Columbia. Montana Bur. Mines & Geol., Special publ. 74: 171-185, 1976.
Davis, G., Monger, JWH & Burchfiel, BC: Mesozoic construction of the Cordilleran “collage”, central British Columbia to central California. Pacific Coast Paleography symposium 2, Soc. Economic Paleontologists and Mineralogists, Los Angeles: 1-32, 1978.
Gibson, DW: Triassic rocks of the Rocky Mountain foothills and front ranges of northeastern British Columbia and west-central Alberta. Geol. Surv. Canada Bull. 247, 1975.
Photo of the large belemnite (Atractites sp?) and ammonites (Sunrisites & Badouxia) from the Lower Jurassic (Late Hettangian), Last Creek Formation (Castle Pass member), Taseko Lakes area, British Columbia, Canada in the collection of the deeply awesome John Fam.
Photo: A drawer of Juvavites sp. in the collections of the Geological Survey of Canada. These rarely seen Upper Triassic (Carnian to Norian) ammonoids were collected over many decades by geologists of the Geological Survey of Canada from Northeastern British Columbia. Photo care of the deeply awesome John Fam.
Photo: Grambergia sp. from the Early Anisian (Middle Triassic) ammonoid biostratigraphy of northeastern British Columbia, Canada. Collection of Fossil Huntress.
Photo: Alsatites proaries, Coll. Reiter, Neoammoniten, 30 July 2011, 19:26:10
Sunday, 20 October 2024
ALCIDS AUKS: PUFFLINGS AND DUTIFUL PARENTS
Their sexy orange beaks shift from a dull grey to bright orange when it is time to attract a mate. While not strictly monogamous, most Puffins choose the same mate year upon year producing adorable chicks or pufflings (awe) from their mating efforts.
Female Puffins produce one single white egg which the parents take turns to incubate over a course of about six weeks. Their dutiful parents share the honour of feeding the wee pufflings five to eight times a day until the chick is ready to fly. Towards the end of July, the fledgeling Puffins begin to venture from the safety of their parents and dry land. Once they take to the seas, mom and dad are released from duty and the newest members of the colony are left to hunt and survive on their own.
These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crevices among rocks or in burrows in the soil. Two species, the tufted puffin and horned puffin are found in the North Pacific Ocean, while the Atlantic puffin is found in the North Atlantic Ocean.
These Atlantic Puffins are one of the most famous of all the seabirds and form the largest colony in Southern Britain. They live about 25 years making a living in our cold seas dining on herring, hake and sand eels. Some have been known to live to almost 40 years of age. They are good little swimmers as you might expect, but surprisingly they are great flyers, too! They are hindered by short wings, which makes flight challenging but still possible with effort. Once they get some speed on board, they can fly up to 88 km an hour.
The oldest alcid fossil is Hydrotherikornis from Oregon dating to the Late Eocene while fossils of Aethia and Uria go back to the Late Miocene. Molecular clocks have been used to suggest an origin in the Pacific in the Paleocene. Fossils from North Carolina were originally thought to have been of two Fratercula species but were later reassigned to one Fratercula, the tufted puffin, and a Cerorhinca species. Another extinct species, Dow's puffin, Fratercula dowi, was found on the Channel Islands of California until the Late Pleistocene or early Holocene.
The Fraterculini are thought to have originated in the Pacific primarily because of their greater diversity in the region. There is only one extant species in the Atlantic, compared to two in the Pacific. The Fraterculini fossil record in the Pacific extends at least as far back as the middle Miocene, with three fossil species of Cerorhinca, and material tentatively referred to that genus, in the middle Miocene to late Pliocene of southern California and northern Mexico.
Although there no records from the Miocene in the Atlantic, a re-examination of the North Carolina material indicated that the diversity of puffins in the early Pliocene was as great in the Atlantic as it is in the Pacific today. This diversity was achieved through influxes of puffins from the Pacific; the later loss of species was due to major oceanographic changes in the late Pliocene due to closure of the Panamanian Seaway and the onset of severe glacial cycles in the North Atlantic.