Showing posts with label sex. Show all posts
Showing posts with label sex. Show all posts

Saturday, May 18, 2024

SLOTHS & BLUE GREEN ALGAE

Ever wonder why the slow moving sloth has a slightly greenish hue? Ever consider the sloth at all? Well, perhaps not. Location, location, location, is the mantra for many of us in our macro world, but it is also true for the small world of algae.

Blue green algae is a term used to describe any of a large, heterogeneous group of prokaryotic, principally photosynthetic organisms.

These little oxygenic (oxygen-producing) fellows appeared about 2,000,000,000 to 3,000,000,000 years ago and are given credit for greatly increasing the oxygen content of the atmosphere, making possible the development of aerobic (oxygen-using) organisms and some very special relationships with some of the slowest moving mammals on the planet, the sloths or Folivora.

The tribes of South America who live close to these insect and leaf-eaters, call these arboreal browsers "Ritto, Rit or Ridette, which roughly translates to variations on sleep, sleepy, munching and filthy. Not all that far off when you consider ths sloth and their lifestyle.

The sloth's body and shaggy coat, or pelage, provides a comfy habitat to two types of wee blue-green algae along with various other invertebrates. The hairs that make up the sloth's coat have grooves that help foster algal growth.

And, while Kermit the Frog says, "it's not easy being green," it couldn't be further from the truth for this slow-moving tree dweller. The blue-green algae gives the sloth a natural greenish camouflage, an arrangement that is certainly win-win.

Thursday, May 16, 2024

PARTY OF TWO: ANGLERFISH

The festive lassie you see here is an Anglerfish. They always look to be celebrating a birthday of some kind, albeit solo. This party is happening deep in our oceans and for those that join in, I hope they like it rough.

The wee candle you see on her forehead is a photophore, a tiny bit of luminous dorsal spine. Many of our sea dwellers have these candle-like bits illuminating the depths. You may have noticed them glowing around the eyes of many of our cephalopod friends. 

These light organs can be a simple grouping of photogenic cells or more complex with light reflectors, lenses, colour filters able to adjust the intensity or angular distribution of the light they produce. Some species have adapted their photophores to avoid being eaten, in others, it's an invitation to lunch.

In anglerfish' world, this swaying light is dead sexy. It's an adaptation used to attract prey and mates alike.

Deep in the murky depths of the Atlantic and Antarctic oceans, hopeful female anglerfish light up their sexy lures. When a male latches onto this tasty bit of flesh, he fuses himself totally. He might be one of several potential mates. She's not picky, just hungry. Lure. Feed. Mate. Repeat.

A friend asked if anglerfish mate for life. Well, yes.... yes, indeed they do.

Mating is a tough business down in the depths. Her body absorbs all the yummy nutrients of his body over time until all that's left are his testes. While unusual, it is only one of many weird and whacky ways our fishy friends communicate, entice, hunt and creatively survive and thrive. The deepest, darkest part of the ocean isn't empty — its hungry.

The evolution of fish began about 530 million years ago with the first fish lineages belonging to the Agnatha, a superclass of jawless fish. We still see them in our waters as cyclostomes but have lost the conodonts and ostracoderms to the annals of time. Like all vertebrates, fish have bilateral symmetry; when divided down the middle or central axis, each half is the same. Organisms with bilateral symmetry are generally more agile, making finding a mate, hunting or avoiding being hunted a whole lot easier.

When we envision fish, we generally picture large eyes, gills, a well-developed mouth. The earliest animals that we classify as fish appeared as soft-bodied chordates who lacked a true spine. While they were spineless, they did have notochords, a cartilaginous skeletal rod that gave them more dexterity than the cold-blooded invertebrates who shared those ancient seas and evolved without a backbone. 

Fish would continue to evolve throughout the Paleozoic, diversifying into a wide range of forms. Several forms of Paleozoic fish developed external armour that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many species, including sharks, became formidable marine predators rather than just the prey of arthropods.

Fish in general respire using gills, are most often covered with bony scales and propel themselves using fins. There are two main types of fins, median fins and paired fins. The median fins include the caudal fin or tail fin, the dorsal fin, and the anal fin. Now there may be more than one dorsal, and one anal fin in some fishes.

The paired fins include the pectoral fins and the pelvic fins. And these paired fins are connected to, and supported by, pectoral and pelvic girdles, at the shoulder and hip; in the same way, our arms and legs are connected to and supported by, pectoral and pelvic girdles. This arrangement is something we inherited from the ancestors we share with fish. They are homologous structures.

When we speak of early vertebrates, we are often talking about fish. Fish is a term we use a lot in our everyday lives but taxonomically it is not all that useful. When we say, fish we generally mean an ectothermic, aquatic vertebrate with gills and fins.

Fortunately, many of our fishy friends have ended up in the fossil record. We may see some of the soft bits from time to time, as in the lovely fossil fish found in concretion in Brazil, but we often see fish skeletons. Vertebrates with hard skeletons had a much better chance of being preserved. 

Eohiodon Fish, McAbee Fossil Beds
In British Columbia, we have lovely two-dimensional Eocene fossil fish well-represented from the Allenby of Princeton and the McAbee Fossil Beds. 

We have the Tiktaalik roseae, a large freshwater fish, from 375 million-year-old Devonian deposits on Ellesmere Island in Canada's Arctic. Tiktaalik is a wonderfully bizarre creature with a flat, almost reptilian head but also fins, scales and gills. We have other wonders from this time. 

Canada also boasts spectacular antiarch placoderms, Bothriolepsis, found in the Upper Devonian shales of Miguasha in Quebec.

There are fragments of bone-like tissues from as early as the Late Cambrian with the oldest fossils that are truly recognizable as fishes come from the Middle Ordovician from North America, South America and Australia. At the time, South America and Australia were part of a supercontinent called Gondwana. North America was part of another supercontinent called Laurentia and the two were separated by deep oceans.

These two supercontinents and others that were also present were partially covered by shallow equatorial seas and the continents themselves were barren and rocky. Land plants didn't evolve until later in the Silurian Period. In these shallow equatorial seas, a large diverse and widespread group of armoured, jawless fishes evolved: the Pteraspidomorphi. The first of our three groups of ostracoderms. The Pteraspidomorphi are divided into three major groups: the Astraspida, Arandaspida and the Heterostraci.

The oldest and most primitive pteraspidomorphs were the Astraspida and the Arandaspida. You'll notice that all three of these taxon names contain 'aspid', which means shield. This is because these early fishes — and many of the Pteraspidomorphi — possessed large plates of dermal bone at the anterior end of their bodies. This dermal armour was very common in early vertebrates, but it was lost in their descendants. 

Arandaspida is represented by two well-known genera: Sacabampaspis, from South America and Arandaspis from Australia. Arandaspis have large, simple, dorsal and ventral head shields. Their bodies were fusiform, which means they were shaped sort of like a spindle, fat in the middle and tapering at both ends. Picture a sausage that is a bit wider near the centre with a crisp outer shell.

If you're a keen bean to see an anglerfish that recently washed up on the shores of Newport Beach this past May, hit this link: https://www.theguardian.com/us-news/2021/may/11/deep-sea-anglerfish-california-beach-finding-nemo. Kudos for my colleague, Giovanni, bringing this gloriously horrific lovely to my attention. 

Monday, April 29, 2024

WOOLLY MAMMOTHS: ANCIENT SNOW POUGHS

Woolly Mammoths, Mammuthus primigenius,  have always held wonder for me. These massive, hairy — and likely very smelly beasts — lived alongside us for a time. 

If you stood beside him and reached way up, you might be able to touch his tusks but likely not reach up to his mouth or even his eyes. 

He had a shaggy coat of light or dark coloured hair with long outer hair strands covering a dense thick undercoat. His oil glands would have worked overtime to secrete oils, giving him natural waterproofing. Some of the hair strands we have recovered are more than a meter in length. These behemoth proboscideans boasted long, curved tusks, little ears, short tails and grazed on leaves, shrubs and grasses that would have been hard work to get at as much of his world was covered in ice and snow during his reign.

We first see Woolly Mammoths in northeastern Siberia dating back 700,000 years. We find them in East Asia as far back as 800,000 years ago. They arose from the massive steppe mammoths, Mammuthus trogontherii, slowly evolving traits we see in this older species to the mammoths we think of today. 

Over time, their body size shrank and their teeth and tusks evolved to take advantage of the tough vegetation available to those few animals who could chew their way through ice and snow and work these tundra grasses into a digestible form. 

The enamel plates of their cheek teeth multiplied while the enamel itself became thinner. Tusks slowly took on more of a curved to act as ploughs for the snow. 

Those smaller than their predecessors, they were still formidable. Their size offered protection against predators once full grown. Sadly for the juveniles, they offered tasty prey to big cats like Homotherium who roamed these ancient grasslands alongside them.

The Mammoths of the Steppe spread to the northern areas of Eurasia, down through Europe, into the British Isles to Spain and crossed over to populate North America via the Bering Isthmus. It was the lowered sea levels during the last Ice Age that exposed dry land between Asia and the Americas. Here in this flat, grassy treeless plain known as the Bering Land Bridge or Isthmus, animals, including humans, could migrate from Europe west into North America.

The woolly mammoth coexisted with our ancestors who made good use of their bones and tusks for tools, housing, art and food. The last of their lineage died out relatively recently on Wrangel Island until 4,000 years ago — a time when we were making our first harps and flutes in Egypt, dams, canals and stone sculptures in Sumer, using numbers for the first time and using tin to make tools.

Monday, April 15, 2024

TURTLE SHELLS: HOME SWEET ARMOUR

Turtle shells are different from the body armour or armoured shells we see adorning dinosaurs like the ankylosaurs. 

Ankylosaurs were blessed with huge plates of bone embedded into their skin that acted as a natural shield against predators. Crocodilians have these same bony plates, or osteoderms, embedded in their skin to give them extra protection. 

We find similar body armour on armadillos. Yet, armadillos, crocodiles and ankylosaurs each evolved body armour that differs significantly from that found in turtles. 

Remarkably, the carapace we see in fully grown turtles is formed from different parts of their skeletons. And, once fully formed, turtle shell fully integrates with the backbone and ribs, growing over the animal in a domed carapace — both protection and home sweet home. 

When we look to the oldest known members of the turtle lineage, Proterochersis and Proganochelys, found as fossils in 210 million-year-old outcrops in present-day Germany and Poland. Like the turtles we find today, these stem-turtles already had fully formed shells — special bony or cartilaginous shell that originates in their ribs. It is a useful adaptation to help deter predators as their soft interior makes for a tasty snack. 

Though I have never eaten turtle (and never will), it was a common and sought after meat for turtle soup. Years ago, I read of Charles Darwin craving it after trying it for the first time on his trip in 1831 aboard the HMS Beagle. It seems Charlie like to taste every exotic new species he had the opportunity to try.

Turtle armour is made of dermal bone and endochondral bones from their vertebrae and rib cage. It is fundamentally different from the armour seen on our other vertebrate friends and the design creates some unique features in turtles. 

Because turtle ribs fuse together with some of their vertebrae, they have to pump air in and out of the lungs with their leg muscles. 

Another unusual feature in turtles is their limb girdles, pectoral and pelvic, which have come to lie within their rib cage, a feature that allows some turtles to pull their limbs inside the shell for protection. 

Sea turtles didn't develop this behaviour or ability and do not retract into their shells like other turtles.

Armadillos have armour formed by plates of dermal bone covered in relatively small, overlapping epidermal scales called scutes, composed of bone with a covering of horn. In crocodiles, their exoskeletons form their armour, similar to ankylosaurs. A bit of genius design, really. It is made of protective dermal and epidermal components that begin as rete Malpighii: a single layer of short, cylindrical cells that lose their nuclei over time as they transform into a horny layer.

Depending on the species and age of the turtle, turtles eat all kinds of food including seagrass, seaweed, crabs, jellyfish, and shrimp,. That tasty diet shows up in the composition of their armour as they have oodles of great nutrients to work with. The lovely example you see here is from the Oxford Museum collections.

Friday, March 29, 2024

AMYLASE: YOU ARE WHAT YOU EAT


The old adage, you are what you eat, might be best amended to you are what you can digest. 

For all the mammals, you and I included, we need the amylase gene (AMY). It codes for a starch-digesting enzyme needed to break down the vegetation we eat. 

Humans, dogs and mice have record numbers of the amylase gene. The AMY gene copy number increases in mammal populations where starch-based foods are more abundant. Think toast and jam versus raw chicken.

A good example of this is seen when we compare wolves living in the wild to dogs from agricultural societies. Dogs split off the lineage from wolves around 30,000–40,000 years ago. 

Domesticated dogs have extra copies of amylase and other genes involved in starch digestion that contribute to an increased ability to thrive on a starch-rich diet, allowing Fido to make the most of those table scraps. Similar to humans, some dog breeds produce amylase in their saliva, a clear marker of a high starch diet. So do mice, rats, and pigs, as expected as they live in concert with humans. Curiously, so do some New World monkeys, boars, deer mice, woodrats, and giant African pouched rats. 

More like cats and less like other omnivores, dogs can only produce bile acid with taurine and they cannot produce vitamin D, which they obtain from animal flesh. Also, more like cats, dogs require arginine to maintain their nitrogen balance. These nutritional requirements place dogs halfway between carnivores and omnivores.

The amount of AMY and starch in the diet varies among subspecies, and sometimes even amongst geographically distinct populations of the same species. I was at a talk recently given by Alaskan wolf researchers who shared that two individual packs of wolves separated by less than a kilometre ate vastly different diets. This had me thinking about what we eat and it is mostly driven by what is on offer. 

Diet impacts our genetics and this, in turn, allows the fittest to eat, digest and survive. While wolves win the carnivore contest, they will still eat opportunistically and that includes vegetation when other food is scarce. Would they evolve similar levels of AMY as humans, dogs and mice? Maybe if their diets evolved to be similar. Likely. The choice would be that or starvation.

The evolution of amylase in other domesticated or human commensal mammals remains an alluring area of inquiry.

Reference: 

Amylase in Dietary Food Preferences in Mammals: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6516957/

Tuesday, February 27, 2024

CIBELELLA CORONATA

Cibelella Coronata / Photo: Alexei Molchanov
A spectacular creamy toned specimen of the trilobite Cibelella Coronata striking a very animated pose. 

The Genal spines give this fellow a bit of a starship look as though taking off in flight. 

This beauty is from upper Ordovician deposits along the Neva River at the head of the Gulf of Finland on the Baltic Coast, Saint Petersburg, Russia.


Monday, February 26, 2024

FOSSIL FISHAPODS OF NUNAVUT

Qikiqtania wakei, a fishapod & relative to tetrapods
You will likely recall the amazing tetrapodomorpha fossil found on Ellesmere Island in the Canadian Arctic in 2004, Tiktaalik roseae. 

These were advanced forms transitional between fish and the early labyrinthodonts playfully referred to as fishapods — half-fish, half-tetrapod in appearance and limb morphology. 

Up to that point, the relationship of limbed vertebrates (tetrapods) to lobe-finned fish (sarcopterygians) was well known, but the origin of significant tetrapod features remained obscure for the lack of fossils that document the sequence of evolutionary changes — until Tiktaalik. 

While Tiktaalik is technically a fish, this fellow is as far from fish-like as you can be and still be a card-carrying member of the group. 

Interestingly, while Neil Shubin and crew were combing the icy tundra for Tiktaalik, another group was trying their luck just a few kilometres away. 

A week before the eureka moment of Tiktaalik's discovery, Tom Stewart and Justin Lemberg unearthed material that we now know to be a relative of Tiktaalik's. 

Meet Qikiqtania wakei, a fishapod and close relative to our dear tetrapods — and cousin to Tiktaalik — who shares features in the flattened triangular skull, shoulders and elbows in the fin. 

Qikiqtania (pronounced kick-kick-TAN-ee-ya)
But, and here’s the amazing part, its upper arm bone (humerus) is specialised for open water swimming, not walking. 

The story gets wilder when we look at Qikiqtania’s position on the evolutionary tree— all the features for this type of swimming are newly evolved, not primitive. 

This means that Qikiqtania secondarily reentered open water habitats from ancestors that had already had some aspect of walking behaviour. 

And, this whole story was playing out 365 million years ago — the transition from water to land was going both ways in the Devonian.

Why is this exciting? You and I descend from those early tetrapods. We share the legacy of their water-to-land transition and the wee bony bits in their wrists and paddles that evolved to become our hands. I know, mindblowing!

Thomas Stewart and Justin Lemberg put in thousands of hours bringing Qikiqtania to life. 

The analysis consisted of a long path of wild events— from a haphazard moment when it was first spotted, a random collection of a block that ended up containing an articulated fin, to a serendipitous discovery three days before Covid lockdowns in March 2020.

Both teams acknowledge the profound debt owed to the individuals, organizations and indigenous communities where they had the privilege to work — Grise Fiord and Resolute Bay— Ellesmere Island in Nunavut, the largest and northernmost territory of Canada. 

Part of that debt is honoured in the name chosen for this new miraculous species. 

Aerial View of Ellesmere Island
The generic name, Qikiqtania (pronounced kick-kick-TAN-ee-ya), is derived from the Inuktitut words Qikiqtaaluk and Qikiqtani which are the traditional place name of the region where the fossil was discovered. 

The specific name, wakei, is in memory of the evolutionary biologist David Wake — colleague, mentor and friend. 

He was a professor of integrative biology and Director and curator of herpetology at the Museum of Vertebrate Zoology at the University of California, Berkeley who passed away in April 2021. 

Wake is known for his work on the biology and evolution of salamanders and vertebrate evolutionary biology. 

If you look at the photo on the left you can imagine visiting these fossil localities in Canada's far north.

Qikiqtania was found on Inuit land and belongs to the community. Thomas Stewart and his colleagues were able to conduct this research because of the generosity and support of individuals in the hamlets of Resolute Bay and Grise Fiord, the Iviq Hunters and Trappers of Grise Fiord, and the Department of Heritage and Culture, Nunavut.

To them, on behalf of the larger scientific community — Nakurmiik. Thank you! 

Here is the link to Tom Stewart's article in The Conversation & paper in Nature that dropped yesterday:

  1. Stewart, Thomas A.; Lemberg, Justin B.; Daly, Ailis; Daeschler, Edward B.; Shubin, Neil H. (2022-07-20). "A new elpistostegalian from the Late Devonian of the Canadian Arctic". Nature. doi:10.1038/s41586-022-04990-w. ISSN 0028-0836.
  2. Stewart, Thomas. "Meet Qikiqtania, a fossil fish with the good sense to stay in the water while others ventured onto land" The Conversation. Retrieved 2022-07-20.

Image One: An artist’s vision of Qikiqtania enjoying its fully aquatic, free-swimming lifestyle. Alex Boersma, CC BY-ND

Image Two: A new elpistostegalian from the Late Devonian of the Canadian Arctic, T. A. Stewart, J. B. Lemberg, A. Daly, E. B. Daeschler, & N. H. Shubin.

A huge shout out to the deeply awesome Neil Shubin who shared that the paper had been published and offered his insights on what played out behind the scenes!

Thursday, February 22, 2024

KEPPLERITES FROM THE KURSK REGION

This glorious chocolate block contains the creamy grey ammonite Kepplerites gowerianus (Sowerby 1827) with a few invertebrate friends, including two brachiopods: Ivanoviella sp., Zeilleria sp. and the deep brown gastropod Bathrotomaria sp. There is also a wee bit of petrified wood on the backside.

These beauties hail from Jurassic, Lower Callovian outcrops in the Quarry of Kursk Magnetic Anomaly (51.25361,37.66944), Kursk region, Russia. Diameter ammonite 70мм. 

Back in the USSR — in the mid-1980s — during the expansion and development of one of the quarries, an unusual geological formation was found. This area had been part of the seafloor around an ancient island surrounded by Jurassic Seas. 

The outcrops of this geological formation turned out to be very rich in marine fossils. This ammonite block was found there years ago by the deeply awesome Emil Black. Sadly, he has not been able to collect there for some time. In more recent years, the site has been closed to fossil collecting and is in use solely for the processing and extraction of iron ore deposits.

Friday, February 16, 2024

UPTHRUSTING PLATES: WASHINGTON GEOLOGY

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. The shifting continues, subtly changing the landscape like a breath. We only notice when pockets of resistance manifest as earthquakes, some newsworthy, some all but unnoticed. For now, the more extreme movement has subsided laterally and continues vertically, pushing California towards the North Pole. Hello Baja-BC.

The upthrusting of plates move our mountain ranges skyward – the path of least resistance. And it is this dynamic movement that's created the landscape we see today.

The 3,000 meters of the stratigraphic section of the Chuckanut Formation along Chuckanut Drive span an age range of just a few million years. The lower part is late Paleocene with a radiometric age of around 56 million years. The upper part of the section is early Eocene. The fossils found here lived and died very close to where they are now but in a much warmer, wetter, 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 during 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 giving 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. 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.

Sumas Eocene Shorebird Trackway
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 and bird trackways from Washington State have caused great excitement over the past few years. Many new trackways have been discovered since the 2009 slides near Sumas. George Mustoe and team collected these important finds, bringing them to the Burke Museum in Washington State to study and make available for display.

The movement of these vertebrates was captured in the soft mud on the banks of an ancient river, one of the only depositional environments favourable for track preservation. The terrestrial paleontological record of Washington State at sites like Chuckanut and Racehorse Creek (U-Pb 53 Ma.) is primarily made up of plant material with some wonderfully enticing mammal, shorebird (seen here) and large Diatryma bird tracks on rare occasions.

Thursday, February 15, 2024

DARWIN'S TOXODON

Toxodon is an extinct large grazing mammal. The first Toxodon fossils were discovered by Charles Darwin on his visit to South America as part of his voyage on the HMS Beagle. 

Darwin wondered at the fossil's strange appearance as it seemed to share features with both rodents and rhinos. 

“Toxodon is perhaps one of the strangest animals ever discovered,” wrote Darwin. He first encountered the creature in Uruguay on November 26th, 1834. 

“Having heard of some giant’s bones at a neighbouring farm-house…, I rode there accompanied by my host, and purchased for the value of eighteen pence the head of the Toxodon.”

The beast’s skeleton, once fully assembled, was a baffling mish-mash of traits. It was huge like a rhino, but it had the chiselling incisors of a rodent—its name means “arched tooth”—and the high-placed eyes and nostrils of a manatee or some other aquatic mammal. “How wonderfully are the different orders, at present time so well separated, blended together in different points of the structure of the toxodon!”

Although Toxodon is not related to rodents, in 2015, it was discovered to be distantly related to rhinoceros. 

Tuesday, February 13, 2024

JUVENILE HAMITES SUBROTUNDUS

A tremendously delicate juvenile Hamites subrotundus (J. Sowerby 1814) from Upper Albian outcrops in Mallorca, the largest of the three Balearic Islands in the Mediterranean at more than 3,600 square kilometers. 

Mallorca has been home to various inhabitants for thousands of years. Sitting some 200 kilometers off Spain’s southeastern, it is a idyllic setting for exploring the rich human and geologic history of this part of the world.

The island is made up of dolomite and limestone from a huge expanse of time, the Mesozoic and Cenozoic—170 million to 10 million years ago— and bookended by two parallel mountain chains top and bottom on its southern and northern coasts. 

As you walk the mountain passes northwest to northeast, you stroll across Miocene deposits 20 million to 13 million years ago that speak of the time in our Earth's recent past when part of the African continent collided with Europe. 

It is famous for its limestone mountains and Roman and Moorish remains. As you can see here, it is also home to some rather nice fossils including this specimen of Hamites subrotundus.

While H. subrotundus is generally a Middle Albian species, this specimen was found in the lower part of Upper Albian in the Cristatum zone by José Juárez Ruiz. José had to piece this lovely together from seven fragments. His labour of love was worth the effort. The final piece is sheer perfection and a beautiful specimen approximately 2.5 cm long.

Mallorca and the other Balearic Islands are geologically an extension of the Baetic Cordillera mountain chain of western Andalusia that extends to Murcia and Valencia. 

They are made up of sediments deposited in the Tethys Sea during the Mesozoic.

Exploring the islands, you can collect from deposits from the Triassic, Cretaceous, Jurassic, and Neogene periods. 

The limestone outcrops contain lovely examples of foraminifers—mainly the species Globigerina.

We also see lovely examples of Hamites (Hamites) subrotundus in the Euhoplites loricatus zone; Euhoplites meandrinus subzone from the Middle Albian (Lower Gault) of Folkestone, Kent, UK. 

Photo, preparation and in the collection of the deeply awesome José Juárez Ruiz. Wright C. W. 1996. Treatise on Invertebrate Paleontology (Part L Mollusca 4 Revised) Volume 4: Cretaceous Ammonoidea

Wednesday, February 7, 2024

VANCOUVER ISLAND'S TRENT RIVER PALAEONTOLOGY

Dan Bowen, Chair, VIPS, Trent River
The rocks that make up the Trent River on Vancouver Island are on the move. They were laid down near of the equator as small, tropical islands. They rode across the Pacific heading north and slightly east over the past 85 million years to where we find them today.

The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. And it is massive. At 103 million km2 (40 million sq mi), it is the largest tectonic plate and continues to grow fed by volcanic eruptions that piggyback onto its trailing edge.

This relentless expansion pushes the Pacific Plate into the North American Plate. The pressure subducts it beneath our continent where it then melts back into the earth. Plate tectonics are slow but powerful forces. 

The island chains that rode the plates across the Pacific smashed into our coastline and slowly built the province of British Columbia. And because each of those islands had a different origin, they create pockets of interesting and diverse geology.

It is these islands that make up the Insular Belt — a physio-geological region on the northwestern North American coast. It consists of three major island groups — and many smaller islands — that stretches from southern British Columbia up into Alaska and the Yukon. These bits of islands on the move arrived from the Late Cretaceous through the Eocene — and continues to this day.

The rocks that form the Insular Superterrane are allochthonous, meaning they are not related to the rest of the North American continent. The rocks we walk over along the Trent River are distinct from those we find throughout the rest of Vancouver Island, Haida Gwaii, the rest of the province of British Columbia and completely foreign to those we find next door in Alberta.

To discover what we do find on the Trent takes only a wee stroll, a bit of digging and time to put all the pieces of the puzzle together. The first geological forays to Vancouver Island were to look for coal deposits, the profitable remains of ancient forests that could be burned to the power industry.

Jim Monger and Charlie Ross of the Geological Survey of Canada both worked to further our knowledge of the complex geology of the Comox Basin. They were at the cutting edge of west coast geology in the 1970s. It was their work that helped tease out how and where the rocks we see along the Trent today were formed and made their way north.

We know from their work that by 85 million years ago, the Insular Superterrane had made its way to what is now British Columbia. 

The lands were forested much as they are now but by extinct genera and families. The fossil remains of trees similar to oak, poplar, maple and ash can be found along the Trent and Vancouver Island. We also see the lovely remains of flowering plants such as Cupanities crenularis, figs and breadfruit.

Heading up the river, you come to a delineation zone that clearly marks the contact between the dark grey marine shales and mudstones of the Haslam Formation where they meet the sandstones of the Comox Formation. Fossilized material is less abundant in the Comox sandstones but still contains some interesting specimens. Here you begin to see fossilized wood and identifiable fossil plant material.

Further upstream, there is a small tributary, Idle Creek, where you can find more of this terrestrial material in the sandy shales. As you walk up, you see identifiable fossil plants beneath your feet and jungle-like, overgrown moss-covered, snarly trees all around you.

Walking west from the Trent River Falls at the bottom, you pass the infamous Ammonite Alley, where you can find Mesopuzosia sp. and Kitchinites sp. of the Upper Cretaceous (Santonian), Haslam Formation. Minding the slippery green algae covering some of the river rocks, you can see the first of the Polytychoceras vancouverense zone.

Continuing west, you reach the first of two fossil turtle sites on the river — amazingly, one terrestrial and one marine. If you continue, you come to the Inland Island Highway.

The Trent River has yielded some very interesting marine specimens, and significant terrestrial finds. We have found a wonderful terrestrial helochelydrid turtle, Naomichelys speciosa, and the caudal vertebrae of a Hadrosauroid dinosaur. Walking down from the Hadrosaur site you come to the site of the fossil ratfish find — one of the ocean's oddest fish.

Ratfish, Hydrolagus Collie, are chimaera found in the north-eastern Pacific Ocean today. The fossil specimen from the Trent would be considered large by modern standards as it is a bruiser in comparison to his modern counterparts. 

This robust fellow had exceptionally large eyes and sex organs that dangled enticingly between them. You mock, but there are many ratfish who would differ. While inherently sexy by ratfish standards, this fellow was not particularly tasty to their ancient marine brethren (or humans today) — so not hugely sought after as a food source or prey.

A little further again from the ratfish site we reach the contact of the two Formations. The rocks here have travelled a long way to their current location. With them, we peel away the layers of the geologic history of both the Comox Valley and the province of British Columbia.

The Trent River is not far from the Puntledge, a river whose banks have also revealed many wonderful fossil specimens. The Puntledge is also the name used by the K'ómoks First Nation to describe themselves. They have lived here since time immemorial. Along with Puntledge, they refer to themselves as Sahtloot, Sasitla and Ieeksun.

References: Note on the occurrence of the marine turtle Desmatochelys (Reptilia: Chelonioidea) from the Upper Cretaceous of Vancouver Island Elizabeth L. Nicholls Canadian Journal of Earth Sciences (1992) 29 (2): 377–380. https://doi.org/10.1139/e92-033; References: Chimaeras - The Neglected Chondrichthyans". Elasmo-research.org. Retrieved 2017-07-01.

Directions: If you're keen to explore the area, park on the side of Highway 19 about three kilometres south of Courtenay and hike up to the Trent River. Begin to look for parking about three kilometres south of the Cumberland Interchange. There is a trail that leads from the highway down beneath the bridge which will bring you to the Trent River's north side.

Monday, February 5, 2024

CARNOTAURUS SASTREI: FLESH EATING BULL

Carnotaurus sastrei, a genus of large theropod dinosaurs that roamed the southern tip of Argentina, South America during the Late Cretaceous, 72 to 69.9 million years ago. His name means "flesh-eating bull,' and he lives up to it.

This fellow — or at least his robust skull with the short, knobby eyebrow horns and fierce-looking teeth — is on display at the Natural History Museum in Madrid, Spain. For now, he is the only known genus of this species of bipedal predator.

The first specimen of Carnotaurus sastrei was found in Chubut on vast plains between the Andes Mountains and the Atlantic Ocean. A physician, Dr. A'ngel Tailor noticed a large concretion showing some bone fragments. A team led by José F. Bonaparte excavated the find in 1984 as part of a paleontological expedition funded by the Argentine Museum of Natural Sciences.

Sadly, Bonaparte — the Maestro del Mesozoico — passed away the 18th February 20220 at the age of 91. He spent the majority of his career as head of the Vertebrate Palaeontology Division of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia,” in Buenos Aires. Bonaparte opened up the vertebrate finds of Argentina to the world. He was instrumental in the finding, excavating and naming many iconic dinosaurs — Carnotaurus, Amargasaurus, Abelisaurus, Argentinosaurus, Noasaurus along with the finding of the first fossilised remains of Mesozoic South American mammals. He mentored many palaeontologists who will miss his keen eye and tremendous work ethic — Luis Chiappe, Rodolfo Coria, Agustín Martinelli, Fernando Novas, Jaime Powell, Guillermo Rougier, Leonardo Salgado, Sebastián Apesteguía and many others.

His excavation of Carnotaurus was the first of its kind and he recognized that the skull is quite unusual. Initially, it has a very marine reptile feel — but make no mistake this guy is clearly a terrestrial theropod. He had smallish, underdeveloped arms — teeny by theropod standards. Once you look closer you see his bull-like horns from whence he gets his name — horns that imply battle between rivals for the best meal, sexual partner and to be the one who leads the herd. 

He was covered in leathery skin lined with rows of cone-shaped nodules or bumps. These get larger as they move towards his spine. He had forward-facing eyes, similar to tyrannosaurs like T-rex and smaller theropods like Velociraptor and Troodon — who had better vision even that T-rex — which would have given him the advantage of binocular vision and depth perception. Forward-facing eyes are also quite helpful with nocturnal hunting — think owls and cats — as they take in more light and help with nighttime predation. So perhaps this flesh-eating bull fancied a late-night snack on his menu from time to time.

Species like squirrels, pigeons and crocodiles have eyes on the sides of their heads. They lack the important competitive feature of well-developed depth perception — being able to easily and estimate distance — but perhaps make up for it with a panorama that offers a wider field of view.   

Thursday, February 1, 2024

AMMONITE OF THE RHÔNE

An exquisite specimen of the delicately ridged ammonite, Porpoceras verticosum, from Middle Toarcian outcrops adjacent the Rhône in southeastern France.

Porpoceras (Buchman, 1911) is a genus of ammonite that lived during the early and middle Toarcian stage of the Early Jurassic. We see members of this genus from the uppermost part of Serpentinum Zone to Variabilis Subzone. These beauties are found in Europe, Asia, North America and South America.

Ammonites belonging to this genus have evolute shells, with compressed to depressed whorl section. Flanks were slightly convex and venter has been low. The whorl section is sub-rectangular. 

The rib is pronounced and somewhat fibulate on the inner whorls — just wee nodes here — and tuberculate to spined on the ventrolateral shoulder. It differs from Peronoceras by not having a compressed whorl section and regular nodes or fibulation. Catacoeloceras is also similar, but it has regular ventrolateral tubercules and is missing the classic nodes or fibulation of his cousins.

This specimen hails from southern France near the Rhône, one of the major rivers of Europe. It has twice the average water level of the Loire and is fed by the Rhône Glacier in the Swiss Alps at the far eastern end of the Swiss canton of Valais then passes through Lake Geneva before running through southeastern France. This 10 cm specimen was prepared by the supremely talented José Juárez Ruiz

Monday, January 29, 2024

FOSSILS AND FAUNA OF MADAGASGAR

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

Friday, January 26, 2024

FIRST DINOSAUR FROM VANCOUVER ISLAND

This dapper fellow is a pine needle and horsetail connoisseur. He's a hadrosaurus — a duck-billed dinosaur. They were a very successful group of plant-eaters that thrived throughout western Canada during the late Cretaceous, some 70 to 84 million years ago.

Hadrosaurs lived as part of a herd, dining on pine needles, horsetails, twigs and flowering plants.

Hadrosaurs are ornithischians — an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. They are close relatives and possibly descendants of the earlier iguanodontid dinosaurs. 

They had slightly webbed, camel-like feet with pads on the bottom for cushioning and perhaps a bit of extra propulsion in water. They were primarily terrestrial but did enjoy feeding on plants near and in shallow water. There had a sturdy build with a stiff tail and robust bone structure. 

At their emergence in the fossil record, they were quite small, roughly three meters long. That's slightly smaller than an American bison. They evolved during the Cretaceous with some of their lineage reaching up to 20 meters or 65 feet.

Hadrosaurs are very rare in British Columbia but a common fossil in our provincial neighbour, Alberta, to the east. Here, along with the rest of the world, they were more abundant than sauropods and a relatively common fossil find. They were common in the Upper Cretaceous of Europe, Asia, and North America.

There are two main groups of Hadrosaurs, crested and non-crested. The bony crest on the top of the head of the hadrosaurs was hollow and attached to the nasal passages. It is thought that the hollow crest was used to make different sounds. These sounds may have signalled distress or been the hadrosaur equivalent of a wolf whistle used to attract mates. Given their size it would have made for quite the trumpeting sound.

This beautiful specimen graces the back galleries of the Courtenay and District Museum on Vancouver Island, British Columbia, Canada. I was very fortunate to have a tour this past summer with the deeply awesome Mike Trask joined by the lovely Lori Vesper. The museum houses an extensive collection of palaeontological and archaeological material found on Vancouver Island, many of which have been donated by the Vancouver Island Palaeontological Society.

Dan Bowen, Chair of the Vancouver Island Palaeontological Society, shared the photo you see here of the first partly articulated dinosaur from Vancouver Island ever found. The vertebrate photo and illustration are from a presentation by Dr. David Evans at the 2018 Paleontological Symposium in Courtenay.  The research efforts of the VIPS run deep in British Columbia and this new very significant find is no exception. A Hadrosauroid dinosaur is a rare occurrence and further evidence of the terrestrial influence in the Upper Cretaceous, Nanaimo Group, Vancouver Island — outcrops that we traditionally thought of as marine from years of collecting well-preserved marine fossil fauna.

CDM 002 / Hadrosauroid Caudal Vertebrae
The fossil bone material was found years ago by Mike Trask of the Vancouver Island Palaeontological Society. You may recall that he was the same fellow who found the Courtenay Elasmosaur on the Puntledge River.

Mike was leading a fossil expedition on the Trent River. While searching through the Upper Cretaceous shales, the group found an articulated mass of bones that looked quite promising.

Given the history of the finds in the area, the bones were thought to be from a marine reptile.

Since that time, we've found a wonderful terrestrial helochelydrid turtle, Naomichelys speciosa, but up to this point, the Trent had been known for its fossil marine fauna, not terrestrial. Efforts were made to excavate more of the specimen, and in all more than 25 associated vertebrae were collected with the help of some 40+ volunteers. Identifying fossil bone is a tricky business. Encased in rock, the caudal vertebrae were thought to be marine reptile in origin. Some of these were put on display in the Courtenay Museum and mislabeled for years as an unidentified plesiosaur.

In 2016, after years of collecting dust and praise in equal measure, the bones were reexamined. They didn't quite match what we'd expect from a marine reptile. Shino Sugimoto, Fossil Preparator, Vertebrate Palaeontology Technician at the Royal Ontario Museum was called in to work her magic — painstakingly prepping out each caudal vertebrae from the block.

Once fully prepped, seemingly unlikely, they turned out to be from a terrestrial hadrosauroid. This is the second confirmed dinosaur from the Upper Cretaceous Nanaimo Group. The first being a theropod from Sucia Island consisting of a partial left thigh bone — the first dinosaur fossil ever found in Washington state.

Dr. David Evans, Temerty Chair in Vertebrate Palaeontology, Department of Natural History, Palaeobiology from the Royal Ontario Museum, confirmed the ID and began working on the partial duck-billed dinosaur skeleton to publish on the find.

Drawing of Trent River Hadrosauroid Caudal Vertebrae
Now fully prepped, the details of this articulated Hadrosauriod caudal vertebrae come to light. We can see the prominent chevron facets indicative of caudal vertebrae with a nice hexagonal centrum shape on its anterior view.

There are well-defined long, raked neural spines that expand distally — up and away from the acoelous centrum. 

Between the successive vertebrae, there would likely have been a fibrocartilaginous intervertebral body with a gel-like core —  the nucleus pulposus — which is derived from the embryonic notochord. This is a handy feature in a vertebrate built as sturdily as a hadrosaur. Acoelous vertebrae have evolved to be especially well-suited to receive and distribute compressive forces within the vertebral column.

This fellow has kissing cousins over in the state of New Jersey where this species is the official state fossil. The first of his kind was found by John Estaugh Hopkins in New Jersey back in 1838. Since that time, we've found many hadrosaurs in Alberta, particularly the Edmontosuaurs, another member of the subfamily Hadrosaurine.

In 1978, Princeton University found fifteen juvenile hadrosaurs, Maiasaura ("good mother lizard") on a paleontological expedition to the Upper Cretaceous, Two Medicine Formation of Teton County in western Montana. 

Their initial finds of several small skeletons had them on the hunt for potential nests — and they found them complete with wee baby hatchlings!

Photo One: Fossil Huntress / Heidi Henderson, VIPS

Photo Two / Sketch Three: Danielle Dufault, Palaeo-Scientific Ilustrator, Research Assistant at the Royal Ontario Museum, Host of Animalogic. 

The vertebrate photo and illustration were included in a presentation by Dr. David Evans at the 2018 BCPA Paleontological Symposium in Courtenay, British Columbia, Canada.

Photo Four: Illustration by the talented Greer Stothers, Illustrator & Natural Science-Enthusiast.

Monday, January 22, 2024

QUENSTEDTOCERAS WITH PATHOLOGY

What you are seeing here is a protuberance extruding from the venter of Quenstedtoceras cf. leachi (Sowerby). It is a pathology in the shell from hosting immature bivalves that shared the seas with these Middle Jurassic, Upper Callovian, Lamberti zone fauna from the Volga River basin. The collecting site is the now inactive Dubki commercial clay quarry and brickyard near Saratov, Russia. 

The site has produced thousands of ammonite specimens. A good 1,100 of those ended up at the Black Hills Institute of Geological Research in Hill City, South Dakota. 

Roughly 1,000 of those are Quenstedtoceras (Lamberticeras) lamberti and the other 100 are a mix of other species found in the same zone. These included Eboraciceras, Peltoceras, Kosmoceras, Grossouvria, Proriceras, Cadoceras and Rursiceras. 

What is especially interesting is the volume of specimens — 167 Quenstedtoceras (Lamberticeras) lamberti and 89 other species in the Black Hills collection — with healed predation injuries. It seems Quenstedtoceras (Lamberticeras) lamberti are the most common specimens found here and so not surprisingly the most common species found injured. Of the 1,000, 655 of the Quenstedtoceras (Lamberticeras) lamberti displayed some sort of deformation or growth on the shell or had grown in a tilted manner. 

Again, some of the Q. lamberti had small depressions in the centre likely due to a healed bite and hosting infestations of the immature bivalve Placunopsis and some Ostrea. 

The bivalves thrived on their accommodating hosts and the ammonites carried on, growing their shells right up and over their bivalve guests. This relationship led to some weird and deformities of their shells. They grow in, around, up and over nearly every surface of the shell and seem to have lived out their lives there. It must have gotten a bit unworkable for the ammonites, their shells becoming warped and unevenly weighted. Over time, both the flourishing bivalves and the ammonite shells growing up and over them produced some of the most interesting pathology specimens I have ever seen.    

In the photo here from Emil Black, you can see some of the distorted shapes of Quenstedtoceras sp. Look closely and you see a trochospiral or flattened appearance on one side while they are rounded on the other. 

All of these beauties hail from the Dubki Quarry near Saratov, Russia. The ammonites were collected in marl or clay used in brick making. The clay particles suggest a calm, deep marine environment. One of the lovely features of the preservation here is the amount of pyrite filling and replacement. It looks like these ammonites were buried in an oxygen-deficient environment. 

The ammonites were likely living higher in the water column, well above the oxygen-poor bottom. An isotopic study would be interesting to prove this hypothesis. There's certainly enough of these ammonites that have been recovered to make that possible. It's estimated that over a thousand specimens have been recovered from the site but that number is likely much higher. But these are not complete specimens. We mostly find the phragmocones and partial body chambers. Given the numbers, this may be a site documenting a mass spawning death over several years or generations.

If you fancy a read on all things cephie, consider picking up a copy of Cephalopods Present and Past: New Insights and Fresh Perspectives edited by Neil Landman and Richard Davis. Figure 16.2 is from page 348 of that publication and shows the hosting predation quite well. 

Photos: Courtesy of the deeply awesome Emil Black. These are in his personal collection that I hope to see in person one day. 

It was his sharing of the top photo and the strange anomaly that had me explore more about the fossils from Dubki and the weird and wonderful hosting relationship between ammonites and bivalves. Thank you, my friend!

Friday, January 19, 2024

YING YANG: ZYCHASPISES

Zenaspis pololica
A Devonian bony fish mortality plate showing a lower shield of Zenaspis podolica (Lankester, 1869) from Lower Devonian deposits of Podolia, Ukraine.

While war rages on in the Ukraine, our hearts go out to those who live and work here contributing much to our understanding of Podolia, a historic region in Eastern Europe, located in the west-central and south-western parts of Ukraine, in northeastern Moldova. 

As I write this, thousands of Ukrainians are arriving at the Palanca border crossing in Moldova on Ukraine's western border to escape the fighting and pincher advance of the Russian military in the north, south and east. 

Looking at a map of the Ukraine, I imagine a torch touching the edges that mental map alighting it with flame — the edges slowly burning and curling in as the world watches and good people on both sides feel that burn.

We look to the Ukraine with our modern lens as we are want to do. Ukraine emerged as the concept of a nation and the Ukrainians as a nationality with the Ukrainian National Revival in the mid-18th century, in the wake of the peasant revolt of 1768-1769 and the eventual partition of the Polish–Lithuanian Commonwealth. They have known a tense love/hate relationship with their neighboring nations for a long while, sharing culture and language but desiring freedom and independence. 

It became an independent state in 1991 with the collapse of the Soviet Union. This fertile part of the world has an archaeology record of human habitation that goes back to the first millennium BC — the oldest known main inhabitants of Ukraine were Cimmerians. They were replaced in Fifth Century BC by Scythians who ruled till 2nd Century BC. The Sarmatian tribes replaced them. Wars, battles and skirmishes ensued until the tribesmen of the dominant horde, the Alanis, could be said to rule in the First Century AD. While our recorded history, our ancestors likely hunted and past through here far earlier. 

Beneath our human habitation and current military action is bedrock that tells the story of the Earth's violent past. The fauna here are from the Silurian and record a time in our Earth's history where the planet suffered a major mass extinction event that wiped out 23 percent of all marine life. It is the only region in Ukraine where 420 million-year-old remains of ichthyofauna can be found near the surface, making them accessible to collection and study. 

Zenaspis is an extinct genus of jawless fish which thrived during the early Devonian. Being jawless, Zenaspis was probably a bottom feeder, dining on debris from the seafloor similar to how flounder, groupers, bass and other bottom-feeding fish make a living.

For the past 150 years, vertebrate fossils have been found in more than 90 localities situated in outcrops along banks of the Dniester River and its northern tributaries, and in sandstone quarries. 

At present, the faunal list of Early Devonian agnathans and fishes from Podolia number seventy-two species, including 8 Thelodonti, 39 Heterostraci, 19 Osteostraci, 4 Placodermi, 1 Acanthodii, and 1 Holocephali (Voichyshyn 2001a).

In Podolia, the Lower Devonian Redbeds strata (the Old Red Formation or Dniester Series) are 1800 metres thick and range from Lochkovian to Eifelian in age (Narbutas 1984; Drygant 2000, 2003).

In their lower part, the Ustechko and Khmeleva members of the Dniester Series are built from lovely multicoloured, mainly red, fine-grained cross-bedded massive quartz sandstones and siltstones with seams of argillites (Drygant 2000).

We see fossils of Zenaspis in the early Devonian of Western Europe. Both Zenaspis pagei and Zenaspis poweri can be found up to 25 centimetres long in Devonian outcrops of Scotland.

Reference: Voichyshyn, V. 2006. New osteostracans from the Lower Devonian terrigenous deposits of Podolia, Ukraine. Acta Palaeontologica Polonica 51 (1): 131–142. Photo care of the awesome Fossilero Fisherman, a fossil hunter devoted to collecting the Lower Devonian Creek exposures of the Ukraine