Showing posts with label archea. Show all posts
Showing posts with label archea. Show all posts

Wednesday, 16 October 2024

NEVADA: AMMONOIDS AND CONODONTS

Nevada is a wonderful place to explore our palaeontological history. The state spans a broad spectrum of exposures showcasing the depth of geologic time. It is an interesting cross-section of young and old — and interestingly, a lovely comparison to the Triassic outcrops in British Columbia.

Exposures of the Upper Triassic, Early Norian, Kerri zone, Luning formation, West Union Canyon, just outside Berlin-Ichthyosaur State Park, Nevada.

The Berlin-Ichthyosaur State Park in central Nevada is a very important locality for the understanding of the Carnian-Norian boundary (CNB) in North America.

Rich ammonoid faunas from this site within the Luning Formation were studied by Silberling (1959) and provided support for the definition of the Schucherti and Macrolobatus zones of the latest Carnian, which are here overlain by well-preserved faunas of the earliest Norian Kerri Zone. Despite its importance, no further investigations have been done at this site during the last 50 years.

Jim Haggart, Mike Orchard and Paul Smith collaborated on a project that took them down to Nevada to look at the conodonts and ammonoids; the group then published a paper, "Towards the definition of the Carnian/Norian Boundary: New data on Ammonoids and Conodonts from central Nevada," which you can find in the proceedings of the 21st Canadian Paleontology Conference; by Haggart, J W (ed.); Smith, P L (ed.); Canadian Paleontology Conference Proceedings no. 9, 2011 p. 9-10.

They conducted a bed-by-bed sampling of ammonoids and conodonts in West Union Canyon during October 2010. The eastern side of the canyon provides the best record of the Macrolobatus Zone, which is represented by several beds yielding ammonoids of the Tropites group, together with Anatropites div. sp. conodont faunas from both these and higher beds are dominated by ornate 'metapolygnthids' that would formerly have been collectively referred to Metapolygnathus primitius, a species long known to straddle the CNB. Within this lower part of the section, they resemble forms that have been separated as Metapolygnathus mersinensis. Slightly higher, forms close to 'Epigondolella' orchardi and a single 'Orchardella' n. sp. occur. This association can be correlated with the latest Carnian in British Columbia.

Ammonoids of the Luning Formation
Higher in the section, the ammonoid fauna shows a sudden change and is dominated by Tropithisbites. Few tens of metres above, but slightly below the first occurrence of Norian ammonoids Guembelites jandianus and Stikinoceras, two new species of conodonts (Gen et sp. nov. A and B) appear that also occur close to the favoured Carnian/Norian boundary at Black Bear Ridge, British Columbia. Stratigraphically higher collections continue to be dominated by forms close to M. mersinensis and 'E.' orchardi.

The best exposure of the Kerri Zone is on the western side of the West Union Canyon. Ammonoids, dominated by Guembelites and Stikinoceras div. sp., have been collected from several fossil-bearing levels. Conodont faunas replicate those of the east section. The collected ammonoids fit perfectly well with the faunas described by Silberling in 1959, but they differ somewhat from the coeval faunas of the Tethys and Canada.

The genus Gonionotites, very common in the Tethys and British Columbia, is for the moment unknown in Nevada. More in general, the Upper Carnian faunas are dominated by Tropitidae, while Juvavitidae are lacking.

After years of reading about the correlation between British Columbia and Nevada, I had the very great pleasure of walking through these same sections in October 2019 with members of the Vancouver Paleontological Society and Vancouver Island Palaeontological Society. It was with that same crew that I had originally explored fossil sites in the Canadian Rockies in the early 2000s. Those early trips led to paper after paper and the exciting revelations that inspired our Nevada adventure.

Saturday, 12 October 2024

NATURAL DYES: INDIGO

Natural dyes are dyes or colourants derived from plants, invertebrates, or minerals. The colours they give us range from muddy to vibrant and have been used to enhance our visual world for many years.

The majority of natural dyes are vegetable dyes from plant sources — roots, berries, bark, leaves, and wood — and other biological sources such as fungi and lichens.

Archaeologists have found evidence of textile dyeing dating back to the Neolithic period. 

In China, dyeing with plants, barks and insects has been traced back more than 5,000 years and by all accounts is our first attempt at the practice of chemistry.

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

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

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

My guide took me to the top of a building so I could look down on rows and rows of coloured vats. In every other one was a man marching in place to work the dye into the wool. Their legs took on the colour from their daily march in place in huge tubs of liquid dye and sheared wool. 

This wool would be considered textile fibre dyed before spinning — dyed in the wool — but most textiles are yarn-dyed or piece-dyed after weaving. In either case, the finished product is quite fetching even if the dyer's legs are less so. 

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

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

Woad, Isatis tinctoria
Plant-based dyes such as Woad, Isatis tinctoria, indigo, saffron, and madder were raised commercially and were important trade goods in the economies of Asia and Europe. 

Across Asia and Africa, patterned fabrics were produced using resist dyeing techniques to control the absorption of colour in piece-dyed cloth.

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

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

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

The plants contain the glycoside indican, a molecule that contains a nitrogenous indoxyl molecule with some glucose playing piggyback. 

Indigo dye is a product of the reaction of indoxyl by a mild oxidizing agent, usually just good old oxygen.

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

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

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

They first appear in the fossil record during the Aptian of the Cretaceous. Their ornate shells fossilize beautifully. I first read about them in Addicott's Miocene Gastropods and Biostratigraphy of the Kern River Area, California. It is a wonderful survey of 182 early and middle Miocene gastropod taxa.

References:

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

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

Miocene Gastropods and Biostratigraphy of the Kern River Area, California; United States Geological Survey Professional Paper 642  

Thursday, 3 October 2024

WASHINGTON STATE PALEONTOLOGY

North Cascades National Park, Washington State, USA
Over vast expanses of time, powerful tectonic forces have massaged the western edge of the continent, smashing together a seemingly endless number of islands to produce what we now know as North America and the Pacific Northwest.

Washington is home to a wide variety of fossils—from new species of fossil crabs to marine mollusks and the fossil palm fronds that symbolize the Chuckanut formation.

We also find fossil whales, bird trackways, fossil sockeye salmon, mammal footprints, mammoth bones & the trace fossil remains of ancient rhino. In the time expanse in which we live our very short human lives, the Earth's crust appears permanent.

A fixed outer shell – terra firma. Aside from the rare event of an earthquake or the eruption of Mount St. Helen’s in 1980, our world seems unchanging, the landscape constant. In fact, it has been on the move for billions of years and continues to shift each day. As the earth’s core began cooling, some 4.5 billion years ago, plates, small bits of continental crust, have become larger and smaller as they are swept up in or swept under their neighbouring plates. Large chunks of the ocean floor have been uplifted, shifted and now find themselves thousands of miles in the air, part of mountain chains far from the ocean today or carved by glacial ice into valleys and basins.

Two hundred million years ago, Washington was two large islands, bits of the continent on the move westward, eventually bumping up against the North American continent and calling it home. Even with their new fixed address, the shifting continues; the more extreme movement has subsided laterally and continues vertically. The upthrusting of plates continue to move our mountain ranges skyward, the path of least resistance.

Fossil Palm Front, Washington State
This dynamic movement has created the landscape we see today and helped form the fossil record that tells much of Washington’s relatively recent history – the past 50 million years. Chuckanut Drive is much younger than other parts of Washington.

The fossils found there lived and died some 40-55 million years ago, very close to where they are now, but in a much warmer, swampy setting. The exposures of the Chuckanut Formation were once part of a vast river delta; imagine, if you will, the bayou country of the Lower Mississippi.

The siltstones, sandstones, mudstones and conglomerates of this formation were laid down about 40-54 million years ago during the Eocene epoch, a time of luxuriant plant growth in the subtropical flood plain that covered much of the Pacific Northwest.

This ancient wetland provided ideal conditions to preserve the many trees, shrubs, and plants that thrived here. Plants are important in the fossil record because they are more abundant and can give us a lot of information about climate, temperature, the water cycle, and humidity of the region. The Chuckanut flora is made up predominantly of plants whose modern relatives live in tropical areas such as Mexico and Central America.

Shore Bird Trackway, Washington State
While less abundant, evidence of the animals that called this ancient swamp home are also found here. Rare bird, reptile, and mammal tracks have been immortalized in the outcrops of the Chuckanut Formation.

Tracks of a type of archaic mammal of the Orders Pantodonta or Dinocerata (blunt foot herbivores), footprints from a small shorebird, and tracks from an early equid or webbed bird track give evidence to the vertebrates that inhabited the swamps, lakes and riverways of the Pacific Northwest 50 million years ago.

Fossil mammals from Washington do get most of the press. The movement of these celebrity vertebrates captured in the soft mud on the banks of a river, one of the depositional environments favourable for track preservation.

The bone record is actually far less abundant than the plant record, except near shell middens, given the preserving qualities of calcium and an alkaline environment. While calcium-rich bones and teeth fossilize well, they often do not get laid down in a situation that makes this possible. Hence the terrestrial paleontological record of Washington State at sites like Chuckanut is primarily made up of plant material.

Wednesday, 2 October 2024

SERENE HUMPBACK WHALES OF THE WEST COAST

This has been the week for Humpback whales visiting the eastern shores of Vancouver Island. These lovelies are, Megaptera novaeangliae, a species of baleen whale for whom I hold a special place in my heart. 

Baleens are toothless whales who feed on plankton and other wee oceanic tasties that they consume through their baleens, a specialised filter of flexible keratin plates that frame their mouth and fit within their robust jaws.

Baleen whales, the Mysticetes, split from toothed whales, the Odontoceti, around 34 million years ago. The split allowed our toothless friends to enjoy a new feeding niche and make their way in a sea with limited food resources. 

There are fifteen species of baleen whales who inhabit all major oceans. Their number include our Humbacks, grays, right whales and the massive blue whale. Their territory runs as a wide band running from the Antarctic ice edge to 81°N latitude. These filter feeders

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, and my cousins on my father's side, whales are known as g̱wa̱'ya̱m. Both the California grey and the Humpback whale live on the coast. Only a small number of individuals in First Nation society had the right to harpoon a whale. This is a practice from many years ago. It was generally only the Chief who was bestowed this great honour. Humpback whales like to feed close to shore and enter the local inlets. Around Vancouver Island and along the coast of British Columbia, this made them a welcome food source as the long days of winter passed into Spring.

Humpback whales are rorquals, members of the Balaenopteridae family that includes the blue, fin, Bryde's, sei and minke whales. The rorquals are believed to have diverged from the other families of the suborder Mysticeti during the middle Miocene. 

While cetaceans were historically thought to have descended from mesonychids—which would place them outside the order Artiodactyla—molecular evidence supports them as a clade of even-toed ungulates—our dear Artiodactyla. 

It is one of the larger rorqual species, with adults ranging in length from 12–16 m (39–52 ft) and weighing around 25–30 metric tons (28–33 short tons). The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. It is known for breaching and other distinctive surface behaviours, making it popular with whale watchers and the lucky few who see them from the decks of our local ferries.

Both male and female humpback whales vocalize, but only males produce the long, loud, complex "song" for which the species is famous. Males produce a complex soulful song lasting 10 to 20 minutes, which they repeat for hours at a time. I imagine Gregorian Monks vocalizing their chant with each individual melody strengthening and complimenting that of their peers. All the males in a group produce the same song, which differed in each season. Its purpose is not clear, though it may help induce estrus in females and bonding amongst the males.

Humpback Whale, Megaptera novaeangliae
Found in oceans and seas around the world, humpback whales typically migrate up to 25,000 km (16,000 mi) each year. 

They feed in polar waters and migrate to tropical or subtropical waters to breed and give birth, fasting and living off their fat reserves. Their diet consists mostly of krill and small fish. 

Humpbacks have a diverse repertoire of feeding methods, including the bubble net technique.

Humpbacks are a friendly species that interact with other cetaceans such as bottlenose dolphins. They are also friendly and oddly protective of humans. You may recall hearing about an incident off the Cook Islands a few years back. Nan Hauser was snorkelling and ran into a tiger shark. Two adult humpback whales rushed to her aid, blocking the shark from reaching her and pushing her back towards the shore. We could learn a thing or two from their kindness. We have not been as good to them as they have been to us.

Like other large whales, the humpback was a tasty and profitable target for the whaling industry. My grandfather and uncle participated in that industry out of Coal Harbour on northern Vancouver Island back in the 1950s. So did many of my First Nation cousins. My cousin John Lyon has told me tales of those days and the slippery stench of that work.

Six whaling stations operated on the coast of British Columbia between 1905 and 1976. Two of these stations were located at Haida Gwaii, one at Rose Harbour and the other at Naden Harbour. Over 9,400 large whales were taken from the waters around Haida Gwaii. The catch included blue whales, fin whales, sei whales, humpback whales, sperm whales and right whales. In the early years of the century, primarily humpback whales were taken. In later years, fin whales and sperm whales dominated the catch. 

Whales were hunted off South Moresby in Haida Gwaii, on the north side of Holberg Inlet in the Quatsino Sound region. It was the norm at the time and a way to make a living, especially for those who had hoped to work in the local coal mine but lost their employment when it shut down. 

While my First Nations relatives hunted whales in small numbers and many years ago, my Norwegian relatives participated in the hunt on a scale that nearly led to their extinction before the process was banned. The Coal Harbour Whaling Station closed in 1967. Once it had closed, my grandfather Einar Eikanger, my mother's father, took to fishing and my uncle Harry lost his life the year before when he slipped and fell over the side of the boat. He was crushed between the hull and a Humpback in rough seas. 

Humpback populations have partially recovered since that time to build their population up to 80,000 animals worldwide—but entanglement in fishing gear, collisions with ships, and noise pollution continue to negatively impact the species. So be kind if you see them. Turn your engine off and see if you can hear their soulful cries echoing in the water.

I did up a video on Humpback Whales over on YouTube so you could see them in all their majesty. Here is the link: https://youtu.be/_Vbta7kQNoM

Tuesday, 1 October 2024

CANADA'S GREAT BEARS

Look at how this protective mamma bear holds her cub in her arms to give him a bit of a wash. 

Her gentle maternal care is truly touching. This mamma has spent late Autumn to Spring in a cave, having birthed them while still hibernation and staying in the den to feed them on her milk.

Black bear cubs stay with their mamma for the first one to three years of their lives while she protects them and teaches them how to thrive in the wild using their keen sense of smell, hearing, vision and strength. Once they are old enough, they will head off into the forest to live solo until they are ready to mate and start a family of their own. 

Mating is a summer affair with bears socializing shoulder to shoulder with potential mates. Once they have mated, black bears head off on their own again to forage and put on weight for their winter hibernation. If the black bear lives in the northern extent of their range, hibernation lasts longer — they will stay in their dens for seven to eight months longer than their southern counterparts. For those that enjoy the warmer climes in the south, hibernation is shorter. If food is available year-round, the bears do not hibernate at all.

The American black bear, Ursus americanus, is native to North America and found in Canada and the United States. 

They are the most common and widely distributed of the three bear species found in Canada. 

There are roughly 650,000 roaming our forests, swamps and streams — meaning there is a good chance of running into them if you spend any amount of time in the wild. 

Full-grown, these fuzzy monkeys will be able to run 48 kilometres (30 miles)  an hour and smell food up to 32 kilometres (20 miles) away.

With their excellent hearing, black bears usually know you are near well before you realize the same and generally take care to avoid you. Those that come in contact with humans often tend to want to check our garbage and hiking supplies for tasty snacks — hey, a free meal is a free meal.    

In British Columbia, we share our province with nearly half of all black bears and grizzly bears that reside in Canada. The 120,000 - 150,000 black bears who live in the province keep our Conservation Officers busy. They account for 14,000 - 25,000 of the calls the service receives each year. Most of those calls centre around their curiosity for the tasty smells emanating from our garbage. They are omnivores with vegetation making up 80-85% of their diet, but they are flexible around that — berries and seeds, salmon or Doritos — bears eat it all. 

And, as with all wild animals, diet is regional. In Labrador, the local black bear population lives mostly on caribou, rodents and voles. In the Pacific Northwest, salmon and other fish form a large part of the protein in their diet versus the bees, yellow jackets and honey others prefer. The braver of their number have been known to hunt elk, deer and moose calves — and a few showy bears have taken on adults of these large mammals. 

Bears hold a special place within our culture and in First Nation mythology in particular — celebrated in art, dance and song. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, the word for black bear is t̕ła'yimother is a̱bas and łaxwa̱lap̓a means to love each other

Kermode or Spirit Bear, Ursus americanus kermodei
From the photos here you can see that black bears are not always black —  ranging in colour from cinnamon to brown, tan, blonde, red — and even white. 

The Kermode or Spirit Bear, Ursus americanus kermodei, a subspecies of black bear found only in British Columbia — and our official provincial mammal — is a distinctive creamy white. 

They are not albinos, their colouring stems from a recessive mutant gene — meaning that if they receive two copies it triggers a single, nonsynonymous nucleotide substitution that halts all melanin production. Well, not all. They have pigmented eyes and skin but no colour in their fur. The white colour is an advantage when you are hunting salmon by day. Salmon will shy away from their black cousins knowing their intention is to enjoy them as a tasty snack. 

Spirit Bears live in the Great Bear Rainforest on British Columbia's north and central coast alongside the Kitasoo/Xai’xais First Nation who call the Kermode moskgm’ol or white bear.

The Kitasoo/Xai’xais have a legend that tells of Goo-wee, Raven making one in every ten black bears white to remind us of the time glaciers blanketed the land then slowly retreated — their thaw giving rise to the bounty we harvest today.  

Black bears of any colour are a wee bit smaller than their brown bear or grizzly bear cousins, with males weighing in at 45 to 400 kilograms (100 to 900 pounds) and females ranging from 38 to 225 kilograms (85 to 500 pounds). 

Small by relative standards but still very large animals. And they are long-lived or at least can be. Bears in captivity can live up to 30 years but those who dwell in our forests tend to live half as long or less from a mixture of local hazards and humans. 

Reference: Wild Safe BC: https://wildsafebc.com/species/black-bear/


Monday, 23 September 2024

BOENY REGION OF MADAGASCAR

Aioloceras besairiei (Collingnon, 1949)
A stunning example of the internal suturing with calcite infill in this sliced Aioloceras besairiei (Collingnon, 1949) ammonite from the Upper Cretaceous (Lower Albian) Boeny region of Madagascar. 

This island country is 400 kilometres off the coast of East Africa in the Indian Ocean and a wonderful place to explore off the beaten track.

Madagascar has some of the most spectacular of all the fossil specimens I have ever seen. This beauty is no exception. The shell has a generally small umbilicus, arched to acute venter, and typically at some growth stage, falcoid ribs that spring in pairs from umbilical tubercles, usually disappearing on the outer whorls. I had originally had this specimen marked as a Cleoniceras besairiei, except Cleoniceras and Grycia are not present in Madagascar. 

This lovely, seen in cross-section, is now far from home and in the collection of a wonderful friend. It is an especially lovely example of the ammonite, Aioloceras besairiei, making it a beudanticeratinae. Cleoniceras and Grycia are the boreal genera. If you'd like to see (or argue) the rationale on the name, consider reading Riccardi and Medina's riveting work from back in 2002, or Collingnon from 1949.

The beauty you see here measures in at a whopping 22 cm, so quite a handful. This specimen is from the youngest or uppermost subdivision of the Lower Cretaceous. I'd originally thought this locality was older, but dating reveals it to be from the Lower Albian, so approximately 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma.

Aioloceras are found in the Cretaceous of Madagascar at geo coordinates 16.5° S, 45.9° E: paleo-coordinates 40.5° S, 29.3° E.; and in four localities in South Africa: at locality 36, near the Mzinene River at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E. 

We find them near the Mziene River, at a second locality north of Hluhluwe where the Mzinene Formation overlies the Aptian-Albian Makatini Formation at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E; and at Haughton Z18, on the Pongola River in the Albian III, Tegoceras mosense beds at 27.3° S, 32.2° E: paleo-coordinates 48.0° S, 7.8° E.

If you happen to be trekking to Madagascar, know that it's big. It’s 592,800 square kilometres (or  226,917 square miles), making it the fourth-largest island on the planet — bigger than Spain, Thailand, Sweden and Germany. The island has an interesting geologic history.

Although there has been a geological survey, which was active extending back well into French colonial times, in the non-French-speaking world our geological understanding of the island is still a bit of a mystery. 

Plate tectonic theory had its beginnings in 1915 when Alfred Wegener proposed his theory of "continental drift." 

Wegener proposed that the continents ploughed through the crust of ocean basins, which would explain why the outlines of many coastlines (like South America and Africa) look like they fit together like a puzzle. Half a century after Wegener there is still no agreement as to whether in continental reconstructions Madagascar should be placed adjacent to the Tanzanian coast to the north (e.g., McElhinny and Embleton,1976), against the Mozambique-Natal coast (Flores 1970), or basically left where it is (Kent 1974, Nairn 1978).

There have been few attempts apart from McKinley’s (1960) comparison of the Karoo succession of southwestern Tanzania with that of Madagascar to follow the famous geological precept of “going to sea.” One critical reason is that although there may be a bibliography of several thousand items dealing with Madagascan geology as Besairie (1971) claims, they are items not generally available to the general public. The vital information gained of the geology of the offshore area by post-World War II petroleum exploration has remained largely proprietary. 

Without this data to draw upon, our understanding remains incomplete. I don't actually mind a bit of a mystery here. It is interesting to speculate on how these geologic puzzle pieces fit together and wait for the big reveal. Still, we have good old Besairie from his 1971, Geologie de Madagascar, and a later précis (Besairie, 1973).

We do know that Madagascar was carved off from the African-South American landmass early on. The prehistoric breakup of the supercontinent Gondwana separated the Madagascar–Antarctica–India landmass from the Africa–South America landmass around 135 million years ago. Madagascar later split from India about 88 million years ago, during the Late Cretaceous, so the native plants and animals on the island evolved in relative isolation. 

It is a green and lush island country with more than its fair share of excellent fossil exposures. Along the length of the eastern coast runs a narrow and steep escarpment containing much of the island's remaining tropical lowland forest. If you could look beneath this lush canopy, you'd see rocks of the Precambrian age stretching from the east coast all the way to the centre of the island. The western edge is made up of sedimentary rock from the Carboniferous to the Quaternary.

Red-Tailed Lemurs, Waiwai & Hedgehog
Madagascar is a biodiversity hotspot. Just as Darwin's finches on the Galápagos were isolated, evolving into distinct species (hello, adaptive radiation), over 90% of the wildlife from Madagascar is found nowhere else. 

The island's diverse ecosystems, like so many on this planet, are threatened by Earth's most deadly species, homo sapien sapiens. 

We arrived back in 490 CE and have been chopping down trees and eating our way through the island's tastier populations ever since. Still, they have cuties like this Red-Tailed Lemur. Awe, right?

Today, beautiful outcrops of wonderfully preserved fossil marine fauna hold appeal for me. The material you see from Madagascar is distinctive — and prolific.

Culturally, you'll see a French influence permeating the language, architecture and legal process. There is a part of me that pictures these lovely Lemurs chatting away in French. "Ah, la vache! Regarde le beau fossile, Hérissonne!"

We see the French influence because good 'ol France invaded sleepy Madagascar back in 1883, during the first Franco-Hova War. Malagasy (the local Madagascarian residents) were enlisted as troops, fighting for France in World War I.  During the Second World War, the island was the site of the Battle of Madagascar between the Vichy government and the British. By then, the Malagasy had had quite enough of colonization and after many hiccuping attempts, reached full independence in 1960. Colonization had ended but the tourist barrage had just begun. You can't stop progress.

If you're interested in learning more about this species, check out the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). R.C. Moore (ed). Geological Soc of America and Univ. Kansas Press (1957), p L394. Or head over to look at the 2002 paper from Riccardi and Medina. 2002. Riccardi, A., C. & Medina, F., A. The Beudanticeratinae and Cleoniceratinae (Ammonitina) from the Lower Albian of Patagonia in Revue de Paléobiologie - 21(1) - Muséum d’Histoire Naturelle de la ville de Genève, p 313-314 (=Aioloceras besairiei (COLLIGNON, 1949). You have Bertrand Matrion to thank for the naming correction. Good to have friends in geeky places!

Collignon, M., 1933, Fossiles cenomaniens d’Antmahavelona (Province d’ Analalave, Madagascar), Ann. Geol. Serv. Min. Madagascar, III, 1934 Les Cephalopods du Trias inferieur de Madagascar, Ann. Paleont. XXII 3 and 4, XXII 1.

Besairie, H., 1971, Geologie de Madagascar, 1. Les terrains sedimentaires, Ann. Geol. Madagascar, 35, p. 463.

J. Boast A. and E. M. Nairn collaborated on a chapter in An Outline of the Geology of Madagascar, that is very readable and cites most of the available geologic research papers. It is an excellent place to begin a paleo exploration of the island.

If you happen to parle français, check out: Madagascar ammonites: http://www.ammonites.fr/Geo/Madagascar.htm

Sunday, 22 September 2024

ANAHOPLITES PLANUS OF VILLEMOYENNE QUARRY

A beautiful specimen of the ammonite, Anahoplites planus (Mantell, 1822) from Albian deposits in Villemoyenne Quarry, Courcelles, Aube, north-central France.

Anahoplites (Hyatt, 1900) is a genus of compressed hoplitid ammonites with flat sides, narrow, flat or grooved venters, and flexious ribs or striae arising from weak umbilical tubercles that end in fine dense ventrolateral nodes.

This lovely has attracted some roommates — an oyster, some bryozoans and worm tubes are attached to her shell.

Anahoplites is now included in the subfamily Anahoplitinae and separated from the Hoplitinae where it was placed in the older in the 1957 edition of the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Genera of the Hoplitinae tend to be more robust, with broader whorls and stronger ribs.

Anahoplites is found in Cretaceous (Middle to the Late Albian) deposits from England, through Europe, all the way to the Transcaspian Oblast region in Russia to the east of the Caspian Sea. The Aube department, named after the local river, is the type locality of the Albian stage (d'ORBIGNY, 1842). 

A. planus from the French Coast
Two formations are recognized in the clay facies (the "Gault" auct.) of the stratotype, the Argiles tégulines de Courcelles (82 m), overlain by the Marnes de Brienne (43 m). The boundary between the two formations is well-defined at the top of an indurated bed and readily identifiable in the field.

This involute (113 mm) specimen shows evidence of cohabitation by some of his marine peers. 

We see two different bryozoa, an oyster and some serpulids making a living and leaving trace fossils on her flat sides. The top specimen was prepared with potase by José Juárez Ruiz of Spain. 

The lovely Anahoplites planus you see here to the lower right was found by Bertus op den Dries on the French coast in Albian deposits near Wissant, P5 and measures in at 8 cm. This on edge view gives you a very good sense of the keel.

Saturday, 14 September 2024

ANCIENT OCTOPUS: KEUPPIA

A sweet as you please example of Keuppia levante (Fuchs, Bracchi & Weis, 2009), an extinct genus of octopus that swam our ancient seas back in the Cretaceous. 

The dark black and brown area you see here is his ink sac which has been preserved for a remarkable 95 million years.

This cutie is in the family Palaeoctopodidae, and one of the earliest representatives of the order Octopoda — and perhaps my favourite fossil. It was this perfect specimen that inspired the logo for the Fossil Huntress brand.  

These ancient marine beauties are in the class Cephalopoda making them relatives of our modern octopus, squid and cuttlefish.

There are two species of Keuppia, Keuppia hyperbolaris and Keuppia levante, both of which we find as fossils. We find their remains, along with those of the genus Styletoctopus, in Cretaceous-age Hâqel and Hjoula localities in Lebanon. 

For many years, Palaeoctopus newboldi (Woodward, 1896) from the Santonian limestones at Sâhel Aalma, Lebanon, was the only known pre‐Cenozoic coleoid cephalopod believed to have an unambiguous stem‐lineage representative of Octobrachia fioroni

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

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

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

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

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

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

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

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

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

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

Tuesday, 3 September 2024

GINKO: THE MAIDENHAIR TREE

Living and Fossil Ginko biloba
The gorgeous yellow lobed leaf you see here is from a Maidenhair Tree — Ginko. These lovelies grow slowly but are well worth the effort with their delicate and distinctive lobed leaves of green and yellow. 

Ginko are Living Fossils native to China. We find them in the fossil record as far back as the Permian, 270 million years, rising with cycads, seed ferns and early conifers. They were part of the low, open, shrubby canopy covering our world well before the first flowering plants arrived. 

Ginko grew when Weigeltisaurus jaekeli, the oldest gliding vertebrates first soared our ancient skies and the first wee beetles munched on decaying wood on our forest floors. It is the long history of predation by beetles and their friends that have made Ginko what they are today — hardy, stinky and weaponized. 

These trees are truly a wonder. Consider that they have lasted since the Permian, living through multiple extinction events that wiped out millions of species on the planet. They are one of the few living things to survive a recent human-made extinction event — the atomic bomb blast in Hiroshima, Japan on August 6, 1945 — weathering one of the most horrifying moments in human history. 

170 Ginko Survived the Atomic Bombing of Hiroshima
When the bomb dropped on Hiroshima it created a fireball that bloomed 1,200 feet in diameter, vaporizing most everything in its radius. 

Somehow 170 resident Gingko trees withstood the ferocity and heat of that blast — and they are still standing to this day, 76 years later. Seemingly impossible, and yet quite true. It is because of their hardy nature that we began looking closely at their genetic make-up. 

Plants with seeds are either angiosperms, our showy flowering plants, or gymnosperms, the naked seed plants. Ginkgo are gymnosperms but in their own subclass, Ginkgoidae. The ginkgos we see growing today are the last remaining member of that subclass.

We see Ginko's rise and diversify in the Permian. By the Jurassic, they had spread across Laurasia, the lands that would become modern Asia. It is this lucky foothold in a young Asia that would eventually save their species. 

From the Jurassic to the Pleistocene their numbers slowly dwindled. We have some great Eocene fossils from outcrops at Quilchena, Tranquille and the McAbee Fossil Beds that show them doing quite well in the interior of British Columbia some 50 million years ago, but this pocket of lush growth seems the exception and not the norm. 

By the Pleistocene, just 2.5 million years ago, glaciation threatened to kill off the last of the ginkgo lineages. Their last stand and platform for global distribution once again was rooted in the forests of central China. Every Ginko you see today originated from that small foothold in China. 

While beautiful, Ginkgo are stinky. I was out for a late stroll the night before last to try and catch a glimpse of the Aurora Borealis up at Queen Elizabeth Park. As I walked along one of the darkened pathways, my nose caught a whiff of something smelly. Think vomit mixed with decaying leaf matter. I looked up to confirm the culprit, a gorgeous bright yellow Ginko backlit from above. 

Ginko in Dan & Lena Bowen's Garden
The reason for their terrible smell is quite clever. It is the result of the chemicals they produce to ward off insects, fungi and bacteria. 

Ginko boast a massive genome comprising some 10.6 billion DNA letters within each strand. You and I boast only three billion letters in our human genome.

Written within this vast genetic code are 41,840 genes or templates that the tree’s cells use to make complex protein molecules that build and maintain each tree and give these stinky lovelies an enviable anti-insect arsenal. 

The photo at the top shows the yellow lobed leaves of a Ginko biloba against an Eocene partial lobe from the McAbee Fossil Beds up near Cache Creek, British Columbia, Canada. The bright yellow is this tree's Autumn colour palette. The bright green leaves you see in the bottom photo are the summer colour palette of this same species. The photo was taken in the summer in Dan and Lena Bowen's garden during the VIPS Saber-toothed Salmon Barbeque. This year, Dan-the-Man is saving some of those lovely lobed leaves to make up some tea from one of the oldest living species in the world. I am excited to give it a try. 

Sunday, 4 August 2024

FOSSILS OF CANADA'S EASTERN SHORES

Hylonomus lyelli, Ancestor of all dinosaurs
The fossil cliffs at Joggins are one of Canada's gems, now a UNESCO World Heritage Site, you can visit to see our ancient world frozen in time. 

Preserved in situ is a snapshot of an entire food chain of a terrestrial Pennsylvanian Coal Age wetland.

The outcrop holds fossil plant life — including impressive standing lycopsid trees that formed the framework of these wetlands — decomposing detritivores in the invertebrates and tetrapods, the predatory carnivores of the day.

The Coal Age trees were fossilized where they stood 300-million-years ago with the remains of the earliest reptiles entombed within. The preservation is quite marvellous with the footprints of creatures who once lived in these wetlands are frozen where they once walked and the dens of amphibians are preserved with remnants of their last meal. 

Nowhere is a record of plant, invertebrate and vertebrate life within now fossilized forests rendered more evocatively. The fossil record at Joggins contains 195+ species of plants, invertebrates and vertebrates. The fossil plant life became the vast coal deposits for which this period of Earth's history is named. 

Recorded in the rock are vertebrate and invertebrate fauna both aquatic and terrestrial. This broad mix of specimens gives us a view into life back in the Pennsylvanian and sets us up to understand their ecological context.
Pennsylvanian Coal Age Ecosystem, 300-Million-Years-Old
The fossil record includes species first defined at Joggins, some of which are found nowhere else on Earth. 

It was here that Sir Charles Lyell, with Sir William Dawson, founder of modern geology, discovered tetrapods — amphibians and reptiles — entombed in the upright fossil trees. 

Later work by Dawson would reveal the first true reptile, Hylonomus lyelli, ancestor of all dinosaurs that would rule the Earth 100 million years later. 

This tiny reptile serves as the reference point where animals finally broke free of the water to live on land. This evolutionary milestone recorded at Joggins remains pivotal to understanding the origins of all vertebrate life on land, including our own species. 

Sir Charles Lyell, author of Principles of Geology, first noted the exceptional natural heritage value of the Joggins Fossil Cliffs, calling them “...the finest example in the world of a natural exposure in a continuous section ten miles long, occurs in the sea cliffs bordering a branch of the Bay of Fundy in Nova Scotia.” Indeed, the world-famous Bay of Fundy with its impressive tides, the highest in the world, and stormy nature exposed much of this outcrop. 

Geological accounts of the celebrated coastal section at Joggins first appear in the published literature in 1828–1829, by Americans C.T. Jackson and F. Alger, and by R. Brown and R. Smith, managers for the General Mining Association in the Sydney and Pictou coal fields. Brown and Smith’s account is the first to document the standing fossil trees.

Joggins Fossil Cliffs Map (Click to Enlarge)
Plan Your Joggins Fossil Cliffs Staycation

Joggins Fossil Cliffs is a Canadian gem — and they welcome visitors. They offer hands-on learning and discovery microscope activities in their Fossil Lab.

You can explore interpretive displays in the Joggins Fossil Centre before heading out to the beach and cliffs with an interpreter.

Their guided tours of the fossil site include an educational component that tells you about the geology, ecology, palaeontology and conservation of this very special site. 

Joggins / Chegoggin / Mi'kmaq L'nu

We know this area as Joggins today. In Mi'kmaw, the language spoken in Mi'kma'ki, the territory of the Mi'kmaq L'nu, the area bears another name, Chegoggin, place of fishing weirs.

Booking Your Class Field Trip

If you are a teacher and would like to book a class field trip, contact the Director of Operations via the contact information listed below. They will walk you through Covid safety and discuss how to make your visit educational, memorable and fun.

Know Before You Go

The Bay of Fundy has the highest tides in the world. Beach walks are scheduled according to the tides and run regardless of the weather. Good low tides but raining, the beach walk goes on. Lovely and sunny but with a high tide, the beach walk must wait. So, you will want to dress for it as they will not be cancelled in the event of rain. Should severe weather be a factor, bookings may need to be rescheduled at the discretion of the Joggins staff.

Any questions about booking your school field trip? Feel free to email:  operations@jogginsfossilcliffs.net or call: 1 (902) 251-2727 EXT 222.

References & further reading:

Joggins Fossil Cliffs: https://jogginsfossilcliffs.net/cliffs/history/

Image: Hylonomus lyelli, Una ricostruzione di ilonomo by Matteo De Stefano/MUSEThis file was uploaded by MUSE - Science Museum of Trento in cooperation with Wikimedia Italia., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=48143186

Image: Arthropleura: Par Tim Bertelink — Travail personnel, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=48915156

Joggins Map: Joggins Fossil Cliffs: https://jogginsfossilcliffs.net/cliffs/history/

Thursday, 18 July 2024

GIGANTIC FOSSIL AMMONITE OF FERNIE

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

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

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

This is the traditional territory of the the Yaq̓it ʔa·knuqⱡi ‘it First Nation who have lived here since time immemorial. There was some active logging along the hillside in 2021, so if you are looking at older directions on how to get to the site be mindful that many of the trailheads have been altered and a fair bit of bushwhacking will be necessary to get to the fossil site proper. That being said, the loggers from CanWel may have clear-cut large sections of the hillside but they did give the ammonite a wide berth and have left it intact.

Wildsight, a non-profit environmental group out of the Kimberly Cranbrook area has been trying to gain grant funding to open up the site as an educational hike with educational signage for folks visiting the Fernie area. It is likely the province of British Columbia would top up those funds if they are able to place the ammonite under the Heritage Conservation Act. CanWel would remain the owners of the land but the province could assume the liability for those visiting this iconic piece of British Columbia's palaeontological history. 

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

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

Titanites occidentalis, the Western Giant, is the second known specimen of this extinct fossil species. 

The first was discovered in 1947 in nearby Coal Creek by a British Columbia Geophysical Society mapping team. When they first discovered this marine fossil high up on the hillside, they could not believe their eyes — both because it is clearly marine at the top of a mountain and the sheer size of this ancient beauty.

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

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

HIKING TO THE FERNIE AMMONITE

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

You access what is left of the trailhead on the south side of the road. You will need to cross the creek to begin your ascent. There is no easy way across the creek and you'll want to tackle this one with a friend when the water level is low. 

The beginning of the trail is not clear but a bit of searching will reveal the trailhead with its telltale signs of previous hikers. This is a moderate 6.3-kilometre hike up & back bushwhacking through scrub and fallen trees. Heading up, you will make about a 246-metre elevation gain. You will likely not have a cellular signal up here but if you download the Google Map to your mobile, you will have GPS to guide you. The area has been recently logged so much of the original trail has been destroyed. There may now be easier vehicle access up the logging roads but I have not driven them since the logging and new road construction.

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

You will want to leave your hammers with your vehicle (no need to carry the weight and this lovely should never be struck with anything more than a raindrop) as this site is best enjoyed with a camera. 

This is a site you will want to wear hiking boots to access. Know that these will get wet as you cross the creek. 

If you would like to see the ammonite but are not keen on the hike, a cast has been made by fossil preparator Rod Bartlett is on display at the Courtenay Museum in Courtenay, Vancouver Island, Canada. 

Respect for the Land / Leave No Trace

As your feet move up the hillside, you can imagine this land 10,000 years ago, rising above great glaciers. Where footfalls trace the steps of those that came before you. This land has been home to the Yaq̓it ʔa·knuqⱡi ‘it First Nation and Ktunaxa or Kukin ʔamakis First Nations whose oral history have them living here since time immemorial. Like them, take only what you need and no more than the land offers — packing out anything that you packed in. 

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


Thursday, 25 April 2024

JURASSIC SEA URCHIN: AM'DA'MA

This lovely little biscuit is a Holectypus sea urchin from 120 million-year-old deposits from the Lagniro Formation of Madagascar.

The specimen you see here is in the collections of my beautiful friend Ileana. She and I were blessed to meet in China many years ago and formed an unbreakable bond that happens so few times in one's life. 

Holectypus are a genus of extinct echinoids related to modern sea urchins and sand dollars. They were abundant from the Jurassic to the Cretaceous (between 200 million and 65.5 million years ago).

This specimen is typical of Holectypus with his delicate five-star pattern adorning a slightly rounded test and flattened bottom. The specimen has been polished and was harvested both for its scientific and aesthetic value. 

I have many wonderful memories of collecting their modern cousins that live on the north end of Vancouver Island and along the beaches of Balaklava Island. In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, sea urchins are known as a̱m'da̱'ma and it is this name that I hear in my head when I think of them.

In echinoids, the skeleton is almost always made up of tightly interlocking plates that form a rigid structure or test — in contrast with the more flexible skeletal arrangements of starfish, brittle stars, and sea cucumbers. Test shapes range from nearly globular, as in some sea urchins, to highly flattened, as in sand dollars. 

Sea Urchin Detail
Living echinoids are covered with spines, which are movable and anchored in sockets in the test. These spines may be long and prominent, as in typical sea urchins and most have lovely raised patterns on their surface. 

In sand dollars and heart urchins, however, the spines are very short and form an almost felt-like covering. The mouth of most echinoids is provided with five hard teeth arranged in a circle, forming an apparatus known as Aristotle’s lantern.

Echinoids are classified by the symmetry of the test, the number and arrangement of plate rows making up the test, and the number and arrangement of respiratory pore rows called petals. Echinoids are divided into two subgroups: regular echinoids, with nearly perfect pentameral (five-part) symmetry; and irregular echinoids with altered symmetry.

Because most echinoids have rigid tests, their ability to fossilize is greater than that of more delicate echinoderms such as starfish, and they are common fossils in many deposits. The oldest echinoids belong to an extinct regular taxon called the Echinocystitoidea. 

They first appeared in the fossil record in the Late Ordovician. Cidaroids or pencil urchins appear in the Mississippian (Early Carboniferous) and were the only echinoids to survive the mass extinction at the Permo-Triassic boundary. Echinoids did not become particularly diverse until well after the Permo-Triassic mass extinction event, evolving the diverse forms we find them in today. 

True sea urchins first appear in the Late Triassic, cassiduloids in the Jurassic, and spatangoids or heart urchins in the Cretaceous. Sand dollars, a common and diverse group today, do not make an appearance in the fossil record until the Paleocene. They remain one of my favourite echinoderms and stand tall amongst the most pleasing of the invertebrates.

Wednesday, 24 April 2024

CHUCKANUT DRIVE: EOCENE TROPICAL PARADISE

A trip along Chuckanut Drive, in northwestern Washington is a chance to view incredible diversity from sea to sky.

An amazing array of plants and animals call this coastline home. 

For the fossil enthusiast, it is a chance to slip back in time and have a bird’s eye view of a tropical paradise preserved in the Eocene strata of various fossil sites. 

Snug up against the Pacific Ocean, this 6000m thick exposure yields a vast number of tropical and flowering plants that you might see in Mexico today. Easily accessible by car, this rich natural playground makes for an enjoyable daytrip just one hour south of the US Border.

Over vast expanses of time, powerful tectonic forces have massaged the western edge of the continent, smashing together a seemingly endless number of islands to produce what we now know as North America and the Pacific Northwest. Intuition tells us that the earth’s crust is a permanent, fixed outer shell – terra firma.

Aside from the rare event of an earthquake or the eruption of Mount St. Helen’s, our world seems unchanging, the landscape constant. In fact, it has been on the move for billions of years and continues to shift each day. As the earth’s core began cooling, some 4.5 billion years ago, plates, small bits of continental crust, have become larger and smaller as they are swept up in or swept under their neighboring plates. 

Large chunks of the ocean floor have been uplifted, shifted and now find themselves thousands of miles in the air, part of mountain chains far from the ocean today or carved by glacial ice into valleys and basins.

Two hundred million years ago, Washington was two large islands, bits of continent on the move westward, eventually bumping up against the North American continent and calling it home. Even with their new fixed address, the shifting continues; the more extreme movement has subsided laterally and continues vertically. 

The upthrusting of plates continues to move our mountain ranges skyward – the path of least resistance. This dynamic movement has created the landscape we see today and helped form the fossil record that tells much of Washington’s relatively recent history – the past 50 million years.

Chuckanut Drive is much younger than other parts of Washington. The fossils found there lived and died some 40-55 million years ago, very close to where they are now, but in a much warmer, swampy setting. The exposures of the Chuckanut Formation were once part of a vast river delta; imagine, if you will, the bayou country of the Lower Mississippi. The siltstones, sandstones, mudstones and conglomerates of the Chuckanut Formation were laid down about 40-54 million years ago during the Eocene epoch, a time of luxuriant plant growth in the subtropical flood plain that covered much of the Pacific Northwest.

This ancient wetland provided ideal conditions to preserve the many trees, shrubs & plants that thrived here. Plants are important in the fossil record because they are more abundant and can give us a lot of information about climate, temperature, the water cycle and humidity of the region. 

The Chuckanut flora is made up predominantly of plants whose modern relatives live in tropical areas such as Mexico and Central America. If you are interesting in viewing a tropical paradise in your own backyard, look no further than the Chuckanut. 

Images and tag lines: Glyptostrobus, the Chinese swamp cypress, is perhaps the most common plant found here. Also abundant are fossilized remains of the North American bald cypress, Taxodium; Metasequoia (dawn redwood), Lygodium (climbing fern), large Sabal (palm) and leaves from a variety of broad leaf angiosperm plants such as (witch hazel), Laurus (laurel), Ficus (fig) and Platanus (sycamore), and several other forms.

While less abundant, evidence of the animals that called this ancient swamp home are also found here. Rare bird, reptile, and mammal tracks have been immortalized in the outcrops of the Chuckanut Formation. Tracks of a type of archaic mammal of the Orders Pantodonta or Dinocerata (blunt foot herbivores), footprints from a small shorebird, and tracks from an early equid or webbed bird track give evidence to the vertebrates that inhabited the swamps, lakes and river ways of the Pacific Northwest 50 million years ago.

The movement of these celebrity vertebrates was captured in the soft mud on the banks of a river, one of the only depositional environments favorable for track preservation.