White Eared Puffbird, Nystalus chacuru |
Metasequoia, the Dawn Redwood |
White Eared Puffbird, Nystalus chacuru |
Metasequoia, the Dawn Redwood |
Collishaw Point, known locally as Boulder Point, Hornby Island |
Upper Cretaceous Nanaimo Group Fossil Concretion |
Dan Bowen, Chair, VIPS. Photo: Deanna Steptoe Graham |
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.West Coast First Nations |
Many of those villages are now deserted, some coalesced, blending together shrinking numbers from smaller villages to form new social units in larger villages. They made their villages close to the bounty of the rivers and sea.
Within the sheltered bays, river heads and remote wilderness along the west coast of Vancouver Island their villages and people were bonded language, culture, marriage, tradition and war. Sometimes they would join forces to trade, sometimes to wage war and sometimes they would battle one another.
Those that live on into the future, the few who have survived and now thrive are the Nuu-chah-nulth you meet today.
Using Nuu-chah-nulth is similar 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 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.
VIPS & VanPS Nootka Crew. Photo: John Fam, VanPS |
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.
Wakash, wakash! A Fossil Crab |
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 Fossil Huntress 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).
What to Know Before You Go — Nootka Trail
The Nootka Trail passes through the traditional lands of the Mowachaht/Muchalat First Nations who have lived in Yuquot since always but today hail from the north island town of Gold River.
As you walk the Nootka Trail and look to land and sea, you share the area with Gray whales, humpback whales, orcas, seals, sea lions, black bears, wolves, cougars, eagles, ravens, sea birds, river otters, slugs 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
In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest — or Kwakwaka'wakw, speakers of Kwak'wala — sockeye salmon are known as ma̱łik.
For the Tk'emlúps te Secwépemc First Nation, people of the confluence, of the Interior of British Columbia, near Kamloops, salmon was the most important of the local fishing stock and the salmon fishing season was a significant social event that warranted the nomination of a Salmon Chief who directed the construction of the hooks, weirs and traps and the distribution of the catch.
In the Interior of the province, archaeological evidence dates the use of salmon as a food source back a mere 3,500 years. While the First Nation groups have an oral history telling us they have lived here since always, 3,500 years falls short of the mark.
The truth, it seems, needed to be teased from the rock. Sheri Burton and Catherine Carlson were able to isolate and amplify mitochondrial DNA from the salmon remains at archaeological sites near Kamloops. The DNA came from the species as Oncorhynchus nerka or Sockeye salmon, preserved in concretion and collected along the southern shores of Kamloops Lake.
The concretions were originally dated as Miocene (24 – 5.5 million years old) by the Geological Survey of Canada, based on pollen grain analysis. However, many local experts, including UBC geology professor W.R. (Ted) Danner (my mentor), W.H. Mathews and Richard Hughes, suspected the remains were much more recent, perhaps the Late Pleistocene. It was a topic that provided lively debate for many years and much pounding on tables during dinner. But it was not until the early 1990s that Catherine Carlson and Ken Klein found definitive proof of this.
Oncorhynchus nerka |
For those on either side of the debate, the results were startling — 18,000 years. It is likely that erosion during the time of deposition had carried pollen down from Miocene layers in surrounding hills, to be deposited around the dead fish, causing the initial over-estimation of the age of the concretions.
This lovely specimen is Oncorhynchus nerka, a Late Pleistocene Fossil Sockeye Salmon, from the fine-grained, silty clays on the south shore of Kamloops Lake, British Columbia, Canada. The site was originally collected in the 1970s by the late geologist and palaeontologist Richard Hughes. I was introduced to the site much later after its rediscovery by Catherine Carlson and Kenneth Klein in the fall of 1991 with the help of local and gracious host, Bill Huxley.
They later wrote up and published a chapter in Rolf Ludvigsen's "Life in Stone: A Natural History of British Columbia's Fossils." It was Huxley who shared its location with John Leahy — a local Kamloops resident and avid fossil hunter — and him with me.
This specimen was collected by John in the 1990s, his tenth partial salmon from this site and the sole one in my collection.
An age of 18,000 plus years sets the fossils firmly as the only salmonids of the Late Pleistocene in North America, a very significant find. The date also changed our ideas about the early climate of the Interior; the Thompson Valley could not have been covered by glacial ice for as long as originally thought. Indeed, it makes the Interior ice-free only 2,000 years after the Last Glacial Maximum and some 4,000 years before our western continental coastline and the Rocky Mountain Foothills.
It has long been accepted that the most recent series of ice ages began approximately 1.6 million years ago, beginning as ice accumulations at higher altitudes with the gradual cooling of the climate. Four times the ice advanced and receded, most recently melting away somewhere around 10,000 years ago. Ice retreated from southwestern British Columbia and the Puget Sound area around 15,000 years ago.
In the southern Interior, ice built up first in the northern Selkirk Mountains, then slowly flowed down into the valleys. Once the valleys were filled, the depth of the ice increased until it began to climb to the highlands and finally covered most of the Interior of British Columbia. Between ice advances, there were times when the Kamloops area was ice-free and the climate warm and hospitable.
Glacial ice was believed to have initiated its most recent retreat from the South Thompson area around 11,000 to 12,000 years ago, but salmon remains from 18,000 years ago suggest that it may have actually begun its northwest decline much earlier — and presenting the possibility of a much warmer climate in the Interior than archaeologists or geologists had originally thought.
Eighteen thousand-year-old salmon also challenge the archaeological notion that the First Nation people of the Interior have had access to salmon as a significant protein source for only a few thousand years.
In the popular view, people living in the Okanagan and Thompson Valleys were felt to have moved to settlements that were semi-permanent about 4,500 years ago. By that time they would have had a seasonally regulated diet composed primarily of salmon and supplemented by local game — deer, elk, small mammals — and available shellfish, birds and plant foods, roots and berries. If salmon were present much earlier, it is possible that this pattern of food utilization may have arisen earlier than thought.
Richard Hughes had originally identified the fossilized Kamloops salmon as Oncorhynchus nerka or Sockeye salmon, the same species found in the 3,500-year-old archaeological sites. But, using the carbon-13 isotope ratio, Klein and Carlson were able to determine that these salmon did not feed on protein from a marine source and relied solely on a freshwater diet.
In other words, they could not have spent part of their life in the ocean, as modern Sockeye salmon do. Based on the specimens’ smaller heads and stunted bodies, the longest measuring in at a pint-sized 11.5 cm, Klein and Carlson feel that the fossils are likely Kokanee — a modern landlocked variety of Sockeye.
If you are wondering about the traditional First Nation use of salmon, this McGill University link is outstanding:http://traditionalanimalfoods.org/fish/searun-fish/page.aspx?id=6446
Trilobite and Sea Scorpion Fossil Trackways |
It shows a nice combination of Cruziana fossil trilobite trackway and eurypterid (sea scorpion) or horseshoe crab trackway on the same matrix.
When we use the term Cruziana, we are not referring to the trilobite species, but to the particular shape and form of the trackway.
In this case, elongate, bilaterally symmetrical burrows preserved along the bedding plane with repeated striations that are mostly oblique to the long dimension. I like to picture a teeny, tiny painter or sculpture with a small putty knife making angled cuts along a line or a wave motion to create a small curved line. Very showy skate skiing is another good visual. Sadly, neither is the case. While a Cruziana trace fossil is most often associated with trilobites, it can be made by other arthropods.
When we see trace fossils — preserved tracks or other signs of behaviour from our marine friends living on the seafloor — they are generally from their furrowing, resting, emerging, walking or striding. They provide a glimpse of how these ancient sea creatures moved about to make a living.
Trilobite and Sea Scorpion Fossil Trackways |
The Tar Springs Formation is recognized on the surface from southwestern Orange County to the Ohio River and is known in the subsurface from central Martin County southwestward (Gray, 1970, 1986).
In Indiana, the Tar Springs Formation is primarily shale, but it also contains scattered thin beds of limestone and massive local lenses of sandstone that on outcrop are differentiated as the Tick Ridge Sandstone Member (Gray, 1986). The formation ranges in thickness from about 70 ft (21 m) to more than 150 ft (46 m) in central Posey County and in southwestern Gibson County (Droste and Keller, 1995). Commonly sandstone predominates in those areas where the Tar Springs is as much as 150 ft (46 m) thick (Droste and Keller, 1995).
Sea Urchin Detail |
Elpistostege watsoni |
In the late 1930s, our understanding of the transition of fish to tetrapods — and the eventual jump to modern vertebrates — took an unexpected leap forward. The evolutionary a'ha came from a single partial fossil skull found on the shores of a riverbank in Eastern Canada.
Meet the Stegocephalian, Elpistostege watsoni, an extinct genus of finned tetrapodomorphs that lived during the Late Givetian to Early Frasnian of the Late Devonian — 382 million years ago.
Elpistostege watsoni — perhaps the sister taxon of all other tetrapods — was first described in 1938 by British palaeontologist and elected Fellow of the Royal Society of London, Thomas Stanley Westoll. Westoll's research interests were wide-ranging. He was a vertebrate palaeontologist and geologist best known for his innovative work on Palaeozoic fishes and their relationships with tetrapods.
As a specialist in early fish, Westoll was asked to interpret that single partial skull roof discovered at the Escuminac Formation in Quebec, Canada. His findings and subsequent publication named Elpistostege watsoni and helped us to better understand the evolution of fishes to tetrapods — four-limbed vertebrates — one of the most important transformations in vertebrate evolution.
Hypotheses of tetrapod origins rely heavily on the anatomy of but a few tetrapod-like fish fossils from the Middle and Late Devonian, 393–359 million years ago. These taxa — known as elpistostegalians — include Panderichthys, Elpistostege and Tiktaalik — none of which had yet to reveal the complete skeletal anatomy of the pectoral fin.
Elpistostege watsoni |
The specimen helped us to understand the origin of the vertebrate hand. Stripped from its encasing stone, it revealed a set of paired fins of Elpistostege containing bones homologous to the phalanges (finger bones) of modern tetrapods and is the most basal tetrapodomorph known to possess them.
Once the phalanges were uncovered, prep work began on the fins. The fins were covered in wee scales and lepidotrichia (fin rays). The work was tiresome, taking more than 2,700 hours of preparation but the results were thrilling.
Origin of the Vertebrate Hand |
Despite this skeletal pattern — which represents the most tetrapod-like arrangement of bones found in a pectoral fin to date blurring the line between fish and land vertebrates — the fin retained lepidotrichia (those wee fin rays) distal to the radials.
This arrangement confirmed an age-old question — showing us for the first time that the origin of phalanges preceded the loss of fin rays, not the other way around.
E. watsoni is very closely related to Tiktaalik roseae found in 2004 in the Canadian Arctic — a tetrapodomorpha species also known as a Choanata. These were advanced forms transitional between fish and the early labyrinthodonts playfully referred to as fishapods — half-fish, half-tetrapod in appearance and limb morphology.
Up to that point, the relationship of limbed vertebrates (tetrapods) to lobe-finned fish (sarcopterygians) was well known, but the origin of major tetrapod features remained obscure for lack of fossils that document the sequence of evolutionary changes — until Tiktaalik. While Tiktaalik is technically a fish, this fellow is as far from fish-like you can be and still be a card-carrying member of the group.
Tiktaalik roseae |
Its fins have thin ray bones for paddling like most fish, but with brawny interior bones that gave Tiktaalik the ability to prop itself up, using his limbs for support. I picture him propped up on one paddle saying, "how you doing?"
Six years after Tiktaalik was discovered by Neil Shubin and team in the ice-covered tundra of the Canadian Arctic on southern Ellesmere Island, a team working the outcrops at Miguasha on the Gaspé Peninsula discovered the only fully specimen of E. watsoni found to date — greatly increasing our knowledge of this finned tantalizingly transitional tetrapodomorph.
E. watsoni fossils are rare — this was the fourth specimen collected in over 130 years of hunting. Charmingly, the specimen was right on our doorstop — extracted but a few feet away from the main stairs descending onto the beach of Miguasha National Park.
L'nu Mi’gmaq First Nations of the Gespe’gewa’gi Region
Miguasha is nestled in the Gaspésie or Gespe’gewa’gi region of Canada — home to the Mi’gmaq First Nations who self-refer as L’nu or Lnu. The word Mi’gmaq or Mi’kmaq means the family or my allies/friends in Mi'kmaw, their native tongue (and soon to be Nova Scotia's provincial first language). They are the people of the sea and the original inhabitants of Atlantic Canada having lived here for more than 10,000 years.
The L'nu were the first First Nation people to establish contact and trade with European explorers in the 16th and 17th centuries — and perhaps the Norse as early as the turn of the Millenium. Sailing vessels filled with French, British, Scottish, Irish and others arrived one by one to lay claim to the region — settling and fighting over the land. As each group rolled out their machinations of discovery, tensions turned to an all-out war with the British and French going head to head. I'll spare you the sordid details but for everyone caught in the crossfire, it went poorly.
North America Map 1775 (Click to Enlarge) |
The bittersweet British victory sparked the American War of Independence.
For the next twenty years, the L'nu would witness and become embroiled in yet another war for these lands, their lands — first as bystanders, then as American allies, then intimidated into submission by the British Royal Navy with a show of force by way of a thirty-four gun man-of-war, encouraging L'nu compliance — finally culminating in an end to the hostilities with the 1783 Treaty of Paris.
The peace accord held no provisions for the L'nu, Métis and First Nations impacted. None of these newcomers was Mi'kmaq — neither friends nor allies.
It was to this area some sixty years later that the newly formed Geological Survey of Canada (GSC) began exploring and mapping the newly formed United Province of Canada. Geologists in the New Brunswick Geology Branch traipsed through the rugged countryside that would become a Canadian province in 1867.
It was on one of these expeditions that the Miguasha fossil outcrops were discovered. They, too, would transform in time to become Miguasha National Park or Parc de Miguasha, but at first, they were simply the promising sedimentary exposures on the hillside across the water — a treasure trove of Late Devonian fauna waiting to be discovered.
In the summer of 1842, Abraham Gesner, New Brunswick’s first Provincial Geologist, crossed the northern part of the region exploring for coal. Well, mostly looking for coal. Gesner also had a keen eye for fossils and his trip to the Gaspé Peninsula came fast on the heels of a jaunt along the rocky beaches of Chignecto Bay at the head of the Bay of Fundy and home to the standing fossil trees of the Joggins Fossil Cliffs.
Passionate about geology and chemistry, he is perhaps most famous for his invention of the process to distil the combustible hydrocarbon kerosene from coal oil — a subject on which his long walks exploring a budding Canada gave him a great deal of time to consider. We have Gesner to thank for the modern petroleum industry. He filed many patents for clever ways to distil the soft tar-like coal or bitumen still in use today.
He was skilled in a broad range of scientific disciplines — being a geologist, palaeontologist, physician, chemist, anatomist and naturalist — a brass tacks geek to his core. Gesner explored the coal exposures and fossil outcrops across the famed area that witnessed the region become part of England and not France — and no longer L'nu.
Following the Restigouche River in New Brunswick through the Dalhousie region, Gesner navigated through the estuary to reach the southern coast of the Gaspé Peninsula into what would become the southeastern coast of Quebec to get a better look at the cliffs across the water. He was the first geologist to lay eyes on the Escuminac Formation and its fossils.
In his 1843 report to the Geologic Survey, he wrote, “...I found the shore lined with a coarse conglomerate. Farther eastward the rocks are light blue sandstones and shales, containing the remains of vegetables. (...) In these sandstone and shales, I found the remains of fish and a small species of tortoise with fossil foot-marks.”
We now know that this little tortoise was the famous Bothriolepis, an antiarch placoderm fish. It was also the first formal mention of the Miguasha fauna in our scientific literature. Despite the circulation of his report, Gesner’s discovery was all but ignored — the cliffs and their fossil bounty abandoned for decades to come. Geologists like Ells, Foord and Weston, and the research of Whiteaves and Dawson, would eventually follow in Gesner's footsteps.
North America Map 1866 (Click to Enlarge) |
This is exciting as it is the lobe-finned fishes — the sarcopterygians — that gave rise to the first four-legged, air-breathing terrestrial vertebrates – the tetrapods.
Fossil specimens from Miguasha include twenty species of lower vertebrates — anaspids, osteostra-cans, placoderms, acanthodians, actinopterygians and sarcopterygians — plus a limited invertebrate assemblage, along with terrestrial plants, scorpions and millipedes.
Originally interpreted as a freshwater lacustrine environment, recent paleontological, taphonomic, sedimentological and geochemical evidence corroborates a brackish estuarine setting — and definitely not the deep waters of the sea. This is important because the species that gave rise to our land-living animals began life in shallow streams and lakes. It tells us a bit about how our dear Elpistostege watsoni liked to live — preferring to lollygag in cool river waters where seawater mixed with fresh. Not fully freshwater, but a wee bit of salinity to add flavour.
References & further reading:
Unescoceratops koppelhusae, Julius Csotonyi |
The Royal Tyrrell Museum of Palaeontology, named in honour of Joseph Burr Tyrrell, is a palaeontology museum and research facility in Drumheller, Alberta, Canada.
This jaw is the holotype specimen of this small leptoceratopsid dinosaur. Only a handful of isolated fossils have been found from this species, including a jaw that is the holotype specimen now in collections at the Royal Tyrell.
The Royal Tyrrell Museum of Palaeontology, named in honour of Joseph Burr Tyrrell, is a palaeontology museum and research facility in Drumheller, Alberta, Canada.
Unescoceratops koppelhusae, RTMP Collections |
The Cleveland Museum of Natural History's Michael Ryan and David Evans of the Royal Ontario Museum in Toronto recently determined that the specimen was a new genus and species.
Unescoceratops is a genus of leptoceratopsid ceratopsian dinosaurs known from the Late Cretaceous (about 76.5-75 million years ago) of Alberta, Canada. Unescoceratops is thought to have been between one and two meters long and less than 91 kilograms. A plant-eater, its teeth were the roundest of all Leptocertopsids.
Dinosaur Provincial Park, Alberta, Canada |
In addition to its particularly beautiful scenery, Dinosaur Provincial Park – located at the heart of the province of Alberta's badlands – is unmatched in terms of the number and variety of high-quality specimens.
To date, they represent more than 44 species, 34 genera and 10 families of dinosaurs, dating back 75-77 million years. This provides us with remarkable insight into life millions of years ago.
The park contains exceptional riparian habitat features as well as badlands of outstanding aesthetic value.
The creamy honey, beige and rust coloured hills around the fossil locality are outstanding examples of major geological processes and fluvial erosion patterns in semi-arid steppes — think glorious!The genus is named to honour the UNESCO World Heritage Site designation for the locality where the specimen was found and from the Greek “ceratops,” which means 'horned face'.
Dr Michael Ryan explained that he meant to honour UNESCO's efforts to increase understanding of natural history sites around the world.
© Julius T. Csotonyi An illustration of Unescoceratops koppelhusae, a plant-eating dinosaur from the Late Cretaceous period that lived approximately 75 million years ago shared with his gracious permission.
ABOUT THE ARTIST
Dr. Julius Csotonyi is a Vancouver-based scientific illustrator and natural history fine artist. He is a featured paleoartist on Season One of BC's Fossil Bounty. Julius has a scientific background in ecology (MSc) and microbiology (PhD) which has taken him to study sensitive ecosystems, from sand dunes in the Rocky Mountain parks to hydrothermal vents at the bottom of the Pacific Ocean.
These experiences have fuelled his strong resolve to work toward preserving our Earth’s biota. Painting biological subjects is one means that he uses to both enhance public awareness of biological diversity and to motivate concern for its welfare.
He paints murals and panels that have appeared in numerous museums including the Smithsonian’s National Museum of Natural History, press release images for scientific publications, books, stamp sets — including the outstanding 2018 “Sharks of Canada” set for Canada Post — and coins for the Royal Canadian Mint. To view more of Julius Csotonyi's exquisite work visit: https://csotonyi.com/
Lytoceras sp. Photo: Craig Chivers |
The concretion prior to prep |
Uintacrinus socialis from Utah, USA |
Crinoids are unusually beautiful and graceful members of the phylum Echinodermata. They resemble an underwater flower swaying in an ocean current.
But make no mistake they are marine animals. Picture a flower with a mouth on the top surface that is surrounded by feeding arms. Awkwardly, add an anus right beside that mouth.
Crinoids with root-like anchors are called sea lilies. They have graceful stalks that grip the ocean floor. Those in deeper water have longish stalks up to 3.3 ft or a meter in length. Then there are other varieties that are free-swimming with only vestigial stalks. They make up the majority of this group and are commonly known as feather stars or comatulids.
Unlike the sea lilies, the feather stars can move about on tiny hook-like structures called cirri. It is these same cirri that allow crinoids to latch to surfaces on the seafloor. Like other echinoderms, crinoids have pentaradial symmetry. The aboral surface of the body is studded with plates of calcium carbonate, forming an endoskeleton similar to that in starfish and sea urchins.
These make the calyx somewhat cup-shaped, and there are few, if any, ossicles in the oral (upper) surface, an area we call the tegmen. It is divided into five ambulacral areas, including a deep groove from which the tube feet project, and five interambulacral areas between them.
Crinoids are alive and well today. They are also some of the oldest fossils on the planet. We have lovely fossil specimens dating back to the Ordovician — if one ignores the enigmatic Echmatocrinus of the Burgess Shale. And they can be quite plentiful. Crinoid fossils, and in particular disarticulated crinoid columnals, can be so abundant that they at times serve as the primary supporting clasts in sedimentary rocks.
Diplomoceras sp. |