PLESIOSAURS OF THE YORKSHIRE COAST

Plesiosaur vertebrae / Liam Langley Collection

These two lovely Plesiosaur vertebrae were found by Liam Langley on fossil field trips to the Yorkshire Coast on the east coast of England.

Plesiosaurus was a large, carnivorous air-breathing marine reptile with strong jaws and sharp teeth that moved through the water with four flippers. We'd originally thought that this might not be the most aerodynamic design but it was clearly effective as they used the extra set to create a wee vortex that aided in their propulsion. In terms of mechanical design, they have a little something in common with dragonflies.

We've recreated plesiosaur movements and discovered that they were able to optimize propulsion to make use of their own wake. As their front flippers paddled in big circular movements, the propelled water created little whirlpools under their bellies.

The back flippers would then paddle between these whirlpools pushing the plesiosaur forward to maximal effect. They were very successful hunters, outcompeting ichthyosaurs who thrived in the Triassic but were replaced in the Jurassic and Cretaceous by these new aquatic beasties. Our ancient seas teemed with these predatory marine reptiles with their long necks and barrel-shaped bodies. Plesiosaurs were smaller than their pliosaur cousins, weighing in at about 450 kg or 1,000 lbs and reaching about 4.5 metres or 15 feet in length. For a modern comparison, they were roughly twice as long as a standard horse or about as long as a good size hippo.

Plesiosaurs first appeared in the latest Triassic, during the Rhaetian. They thrived in the Jurassic and vanished at the end of the Cretaceous in time with the K-Pg extinction event along with a host of other species.

They are one of the marine reptiles that we associate with the infamous Mary Anning, a paleo darling of the early 19th century who found her first fossil specimen in the winter of 1823. These two vertebrae grace the home of the talented Mr. Langley. Anning's plesiosaur can be viewed in London's Natural History Museum.

BRACHIOPOD

Fossil Brachiopod / Prolific Palaeozoic Shellfish

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

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

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

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

NEOCOMITES OF SPAIN

Neocomites (Teschenites) flucticulus

This beautiful specimen is Neocomites (Teschenites) flucticulus a fast-moving nektonic carnivorous ammonite (Thieuloy, 1977) sharing a large boulder with a delicate heteromorph straight-shelled ammonite Bochianites. These beauties were found on a fossil field trip to Hauterivian, Early Cretaceous deposits in the Baetic Cordillera earlier this year. The Baetic Cordillera is one of the main systems of mountain ranges in Spain along the southern and eastern Iberian Peninsula. There are several productive outcrops here that yield lovely Cretaceous ammonites and other marine species.

Neocomites are known from about a dozen offshore marine deep subtidal Cretaceous deposits in France, Hungary, Italy, Romania, Slovakia and Ukraine.

This lovely specimen is the first Neocomites I've seen come out of fossil deposits in Spain. It was found and prepped by the talented Manuel Peña Nieto of Córdoba, Spain.

FOSSIL PREPARATION: MAMMOTH TEETH

Mammoths of Wrangell Island

Mammoths were were herbivore grazers native to Africa, Europe, Asia and North America. They lived out their long lives, 60-80 years, on the mammoth steppe, a periglacial landscape with lush grass vegetation. Mammoths used their well-designed teeth to graze on grasses, leaves, trees, shrubs and moss. Theirs was not a pretty end. Mammoths from this isolated population on Wrangell Island lost the genetic lottery with DNA mutations so abundant that they eventually led to their extinction.

In a paper published in PLOS in 2017, Rebekah Rogers describes that last populations of these once mighty beasts:

"The last woolly mammoths to walk the Earth were so wracked with genetic disease that they lost their sense of smell, shunned company, and had a strange shiny coat."

These genetic mutations may have given the last woolly mammoths "silky, shiny satin fur and let do a loss of olfactory receptors, responsible for the sense of smell, as well as substances in urine involved in social status and attracting a mate." In any event, their end was not a pretty one or the graceful exit one might have imagined. Excess of genomic defects in a woolly mammoth on Wrangel island; Rebekah L. Rogers , Montgomery Slatkin; Published: March 2, 2017https://doi.org/10.1371/journal.pgen.1006601

EOCENE FOSSIL TURTLE

Baena arenosa / Green River Stone Company

An Eocene Cryptodiran Fossil Turtle, Baena arenosa, from fine-grained lime mud outcrops in the Green River Formation, Wyoming, USA.

This fellow, with the extra-long tail, marks the last of his lineage as the extinct family Baenidae appeared first in the Jurassic and died out at the end of the Eocene. We've found specimens of Baena, along with 14 other species of turtles in seven genera and five families in the Lower Eocene San Jose Formation, San Juan Basin of New Mexico.

This specimen is from the Green River Formation of Wyoming which was once the bottom of one of an extensive series of Eocene lakes. The Green River Formation is particularly abundant in beautifully preserved fossil fish, eleven species of reptiles including a 13.5ft crocodile, an armadillo-like mammal, Brachianodon westorum, bats, birds and other fresh-water aquatic goodies.

This specimen of a beautiful Baena was found and prepped by the Green River Stone Company. They purchased their private 12-acre quarry about 20 years ago. It's at the Eocene lake's centre, shared with Fossil Butte National Monument about 24 kilometres (15 miles) west of Kemmerer, Lincoln County, Wyoming.

FOSSIL SAND DOLLARS

Fossil Sand Dollars / Cassibuloid Ancestry

These lovelies are fossil sand dollars with their beautiful five-fold radial symmetry and petal-like pattern. They are echinoids, a group of lovely echinoderms with flattened, rigid, globular skeletons made of thin calcium carbonate plates. They look a bit like sea-biscuits and are sometimes referred to as such.

Their ancestors diverged from an irregular order of echinoids called cassibuloids during the Jurassic. The first true genus of sand dollar, Togocyamus, arose during the Paleocene. While millions of years old, they retain their recognizable form and look very similar to ones we might find living in our oceans and along burrowing on our beaches today.

BLUE MUSSELS

Blue Mussels / Mytilus edulis

Blue mussels live in intertidal areas and inlets attached to rocks and other hard substrates by strong, stretchy thread-like structures called byssal threads.

They are tasty, edible marine bivalves, molluscs, in the family Mytilidae and they've done well for themselves. Mussels have a range of over 4000 km in waters around the world.

Temperature, salinity and food supply are key factors in how mussels grow and have a huge impact on their shape. Environmental stressors cause curvatures to show up in mussel populations and can help us understand environmental changes happening in our local waters.

PREHISTORIC BOWFIN

Calamopleurus cylindricus (Agassiz, 1841) / Collection of David Murphy

This well-preserved fossil fish skull is from Calamopleurus (Agassiz, 1841), an extinct genus of bony fishes related to the heavily armored ray-finned gars.

They are fossil relics, the sole surviving species of the order Amiiformes. Although bowfins are highly evolved, they are often referred to as primitive fishes and living fossils as they retain many of the morphologic characteristics of their ancestors.

This specimen is from Calamopleurus cylindricus of the Family Amiidae. He was found in Lower Cretaceous outcrops of the Santana Formation in the Araripe Basin UNESCO Global Geopark of northeastern Brazil.

YELLOWSTONE NATIONAL PARK

Mammoth Hot Springs Yellowstone National Park

Yellowstone National Park in Wyoming, Montana and Idaho is a 3,500-sq.-mile wilderness recreation area atop a volcanic hot spot.

While the park is mostly in Wyoming, it spreads into parts of Montana and Idaho. Yellowstone features dramatic canyons, alpine rivers, lush forests, hot springs and gushing geysers. You'll maybe know it by its most famous geyser, Old Faithful. It's also home to hundreds of animal species, including Black bear, Canada lynx, Bobcats, Northwestern gray wolves, Bighorn sheep, American bison, elk and antelope.

ANCIENT SALMON OF THE SOUTHERN INTERIOR

Sockeye Salmon / Oncorhynchus nerka

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 began its northwest decline much earlier and indicating a much warmer climate in the Interior than archaeologists or geologists had originally estimated.

Eighteen thousand year-old salmon also challenge the archaeological notion that aboriginal 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. If salmon were present much earlier, it is possible that this pattern of food utilization may have arisen earlier than thought.

HAIDA GWAII BOUNTY

Seafood Bounty / Haida Gwaii, British Columbia

“When the tide is out, the table is set.” This wisdom from those who call Haida Gwaii home is still true today. The enormous difference between high and low tide in Haida Gwaii – up to twenty-three vertical feet – means that twice a day, vast swathes of shellfish are unveiled, free for the taking.

Archaeological evidence tells us that roughly five thousand years ago, gathering shellfish replaced hunting and fishing as a primary food source on the islands. The shellfish meat was skewered on sticks, smoked and stored for use in winter or for travel.

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

While we’ll see that there are two competing schools of thought on Wrangellia’s more recent history, both sides agree that many of the rocks, and the fossils they contain, were laid down somewhere near the equator. They had a long, arduous journey, first being pushed by advancing plates, then being uplifted, intruded, folded, and finally thrust up again. It’s reminiscent of how pastry is balled up, kneaded over and over, finally rolled out, then the process is repeated again.

This violent life story applies to most of the rock that makes up the Insular Belt, the outermost edge of the Cordillera. Once in their present location, the rocks that make up the mountains and valleys of this island group were glaciated and eroded to their present form.

Despite this tumultuous past, the islands have arguably the best-preserved and most fossil-rich rocks in the Canadian Cordillera, dating from very recent to more than 200 million years old. On these details, there is a pretty broad consensus. On much else, including exactly where the Wrangellia terrane was born and how fast it moved to its present position, there is lively debate. But we all agree on their bounty and beauty.

RED-TAILED RAPTOR

Red-Tailed Raptor / Buteo jamaicensis

The majestic Buteo jamaicensis are easily identified by the red upper surface of their broad tails. They are powerful raptors with strong hunting skills.

Most red-tailed hawks have rich brown upper parts with a streaked belly and a dark bar on the underside of the wing, easily viewed when seen from below. The fine detail in their plumage is breathtaking, like little-feathered works of art.

PLEISTOCENE SOCKEYE SALMON

Salmon have permeated First Nations mythology and have been prized as an important food source for thousands of years. 

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 3,500 years. Sheri Burton and Catherine Carlson were able to isolate and amplify mitochondrial DNA from salmon remains from archaeological sites near Kamloops and identified the species as Oncorhynchus nerka, or Sockeye salmon. No older salmon remains had been found in the Kamloops area until the 1970s, when fossil salmon concretions were collected on the south shore of Kamloops Lake.

These concretions were originally dated as Miocene (24 – 5.5 million years old) by the Geological Survey of Canada, based on analysis of pollen grains found in the concretions. However, many local experts, including UBC geology professor W.R. Danner and the late geologists W.H. Mathews and Richard Hughes, suspected the remains were from the much more recent, Late Pleistocene epoch.

It was not until the early 1990s that Catherine Carlson and Ken Klein found definitive proof of this.

By good luck, the fish remains in the Kamloops Lake concretions had not been completely replaced by minerals – enough of the original organic bone collagen remained for radiocarbon dating. The corrected date is approximately 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.

Oncorhychus gorbuscha

The lovely fossil specimen above 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 indicating a much warmer climate in the Interior than archaeologists or geologists had originally estimated.

Eighteen thousand-year-old salmon also challenge the archaeological notion that aboriginal 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 4500 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 including 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.

CRETACEOUS CRANBERRY ARMS

Middle Campanian Plant Fossils / Cranberry Arms

Back in 1996, Vancouver Island local, Jim Bell was moving rocks with his excavator near the Cranberry Arms Pub as part of the Duke Point Highway construction. During one of those loads, he saw a massive fossil palm frond on the side of a rock -- a real showstopper. This wasn't just any frond, he'd scooped up the biggest Geonomites Imperialis ever found.

The fossil caused a stir amongst his construction colleagues but it was nothing compared to the whoops and squeals from local paleo enthusiasts. And rightly so. What do you think of when you envision palm trees? You see warm, tropical beaches, hammocks swaying in the wind, am I right? Most of the fossils found in the Nanaimo Group of Vancouver Island are marine, so a tropical terrestrial site was hot news!

I learned about the site from a very excited paleo colleague calling late one night. He excitedly shared that they'd found a new Late Cretaceous plant site up near Cedar on Vancouver Island. While this is exciting for some, the construction company was not nearly as excited. These were plant fossils after all, and not some new species of dinosaur or ancient hominid. The construction was briefly paused to allow some collecting to take place but was set to continue the following week. They did have a highway to build. Many keen volunteers swooped in to see what could be unearthed. Phone calls were made. Shifts were scheduled. Headlamps were employed as folks took to digging in the dark to maximize the limited collecting window.

Many beautiful specimens were collected. The fossilized leaves, branches and plant remains from broadleaf trees, shrubs, conifers and ferns were immortalized as they slipped into the muds and fine sand of a balmy river environment and slowly buried. 70 million years later, we were doing our best to dig them right back up again.

The fossils included plants and seeds you would expect to find in a much warmer, wetter environment than the climate enjoyed on Vancouver Island today. Perhaps as much as 10° warmer. We see similar specimens of Ensete (banana) and Zamiaceae (cycad) down in Washington State in the Eocene Chuckanut Formation. It is thrilling to see the correlation and transition in both faunal species and environmental conditions for the Pacific Northwest from the Cretaceous to the Eocene. The specimen you see here was generously gifted as a souvenir to attendees of the Third BCPA Symposium in Victoria, British Columbia. Specimen: Middle Campanian Plant Fossils from the Protection Formation, Reserve Member, Cranberry Arms, Cedar, Vancouver Island, British Columbia, Canada.

A RARE BIT OF TURTLE

Fossil Turtle / Aspideretes subquadratus

A rare bit of Turtle Shell from an Aspideretes subquadratus, Upper Cretaceous, Belly River Formation on Sand Creek, Red Deer River, Alberta, Canada.

The holotype (No. 5724) is housed at the Royal Ontario Museum of Palaeontology. It was collected 100 years ago, on a University of Toronto Fossil Expedition in 1919. It was found by Canada's own George F. Sternberg.

MCABEE FOSSIL SITE RE-OPENS

Eocene Plant Fauna / Eohiodon Fish Fossil / McAbee

An Eohiodon rosei and Eocene plant fossils from the McAbee Fossil Beds. McAbee is part of an old lake bed deposited 52 million years ago and is one of the most diverse fossil sites known in British Columbia.

The McAbee beds are known worldwide for their incredible abundance, diversity and quality of fossils including lovely plant, insect and fish species. The site was designated a Provincial Heritage Site under British Columbia's Heritage Conservation Act and closed to the public in July of 2012. This decision has now been reversed.

McAbee re-opened to the public on June 21, 2019, with plans to build out a visitor's centre and educational programs. Funding is in place to have two staff on site this summer to welcome visitors from the general public Thursday to Monday 10AM-5PM. Collecting will be open access with no fees charged. The Province is committed to providing access to scientists, the lay public and tourists interested in local First Nations history. The direction on what happens next at McAbee is being driven by the Heritage Branch in consultation with members of the Shuswap Nation and Bonaparte Band.

Local members of the Bonaparte Band want to share the spiritual significance of the area from a First Nations perspective and see McAbee as an indigenous tourism destination. So it looks like it will be paleontology, archaeology with a cultural focus to add spice. In any case, collection of fossils will continue, likely through the use of day-permits with oversight to ensure significant fossil finds make there way to museums. It is an exploratory year for those running it. They'll be asking a lot of questions from those who drop by then collating that information to make recommendations, seek funding and set a plan for the future. 

DINOSAUR TRACKWAY MOLD

In 2000, Mark Turner and Daniel Helm were tubing down the rapids of Flatbed Creek just below Tumbler Ridge.

As they walked up the shoreline excitement began to build as they quickly recognized a series of regular depressions as dinosaur footprints.

Their discovery spurred an infusion of tourism and research in the area and the birth of the Peace Region Palaeontology Society and Dinosaur Centre.

The Hudson's Hope Museum has an extensive collection of terrestrial and marine fossils from the area. They feature ichthyosaurs, a marine reptile and hadrosaur tracks. The tracks the boys found were identified the following year by Rich McCrae as those of a large quadrupedal dinosaur, Tetrapodosaurus borealis, an ichnotaxon liked to ankylosaurs. The dinosaur finds near Tumbler Ridge are significant. Several thousand bone fragments have been collected, recorded and now reside within the PRPRC collections, making for one of the most complete assemblages for dinosaur material from this age.

DAIHUA FLOWERS

Daihua sanqi, Yunnan Province, China

This lovely fossil is Daihua sanqiong, an unusual 518-million year old sea creature that shares characteristics with our modern comb jelly. The animal’s 18 tentacles are all fine and feather-like, with rows of large cilia adorning the exterior.

The specimen was found in mudstones south of Kunming in the Yunnan Province of southern China by co-author of the study, Professor Hou Xianguang.

This isn’t the first biological discovery found in this particular region. It was named the Daihua Sanqiong after the Dai tribe in Yunnan and “hua” which means “flower” in Mandarin in honor of its flower-like shape. I met the colorful Dai several times while in Kunming in 2018. They are beautiful people with a rich cultural history. It pleases me that this specimen will be named for them.

SHONISAURUS SIKANNIENSIS

Shonisaurus sikanni / Sikanni Chief River

Dr. Betsy Nicholls, Rolex Laureate Vertebrate Palaeontologist from the Royal Tyrrell Museum, excavated the type specimen of Shonisaurus sikanniensis over three field sessions in one of the most ambitious fossil excavations ever ventured.

More than 200 million years ago, the Shonisaurus sikanniensis swan in our ancient seas. A 70-foot long specimen encased in limestone was unearthed on the banks of the Sikanni Chief River. Many beautiful souls contributed to our knowledge and excavation of Shoni including Dean Lomax, Sven Sachs and our own Betsy Nicholls.

CIBELELLA CORONATA

Cibelella Coronata / Photo: Alexei Molchanov

A spectacular specimen of the trilobite Cibelella Coronata from upper Ordovician deposits along the Neva River at the head of the Gulf of Finland on the Baltic Coast, Saint Petersburg, Russia

EVENING ON ISAAC LAKE

Isaac Lake / Bowron Provincial Park

Isaac is the longest of the pristine lakes in the Bowron Lake circuit in Bowron Lake Provincial Park. It is beautiful to paddle and offers well-appointed camping sites on the shore after a full day on the water.

Isaac is picture perfect, nestled between Mount Falkner and Kaza Mountains to the west and southwest and Mount Amos along with the reindeer-themed, Vixen and Dasher Peaks to the east.

TIDEPOOLS: VANCOUVER ISLAND

 

ARNIOCERAS BEDS: SINEMURIAN AMMONITES

Arnioceras semicostatum & Arnioceras miserable

These beauties are from the Arnioceras beds near Last Creek, British Columbia. The fossils found here are from the Lower Jurassic, Lower Sinemurian, Little Paradise Member of the Last Creek formation.

This site is part of the research area for Dr. Howard Tipper, GSC (who is hugely missed) and Dr. Louise Longridge, University of British Columbia.

Several ammonites species can be found here including Arnioceras semicostatum & Arnioceras miserable.

Building on the work of Dr. Howard Tipper and Dr. Louise Longridge, along with Taylor et al from 2001, Pengfei Hou did a Master's thesis through UBC in 2014 on Sinemurian (Early Jurassic) stratigraphy at Last Creek, British Columbia and Five Card Draw, Nevada : paleontology and environmental implications.

As part of that work, he collected over 400 ammonite specimens from the Last Creek Formation in Last Creek, British Columbia and the Sunrise Formation in Five Card Draw, Nevada. The research led to three new species: Tipperoceras n. sp. A, Tmaegoceras obesus n. sp., Arnioceras n. sp. Nice to see Tip getting a nod for his efforts with a species named after him.

The two gastropods you see in the central block look to be Promathildia turritella. The age is certainly correct. Here's hoping a nice grad student takes an interest. The rare but lovely gastros from this area would make an excellent thesis. Perhaps comparing their distribution to their counterparts in Europe.

MIGHTY MARINE REPTILES: ICHTHYOSAURUS

Blue Lias Ichthyosaur / Photo: Lewis Winchester-Ellis

Ichthyosaurs were particularly abundant in the later Triassic and early Jurassic periods, until they were replaced as the top aquatic predators by another marine reptilian group, the Plesiosauria, in the later Jurassic and Cretaceous periods.
In the Late Cretaceous, ichthyosaurs were hard hit by the Cenomanian-Turonian anoxic event. As the deepest (benthos) layers of the seas became anoxic, poisoned by hydrogen sulphide, deep water marine life died off. This caused a cascade that wreaked havoc all the way up the food chain. At the end of that chain were our mighty predaceous marine reptiles. Bounty turned to scarcity and a race for survival began. The ichthyosaurs lost that race as the last lineage became extinct. It may have been their conservative evolution as a genus when faced with a need for adaptation to the world in which they found themselves and/or being outcompeted by early mosasaurs.

NORTH CASCADES

North Cascades, Cascade Range, western North America