SEXUAL DIMORPHISM: PLIENSBACHIAN APODEROCERAS

Apodoceras / Stonebarrow Fossils

Apoderoceras is a wonderful example of sexual dimorphism within ammonites as the macroconch (female) shell grew to diameters in excess of 40 cm – many times larger than the diameters of the microconch (male) shell.

Apoderoceras has been found in the Lower Jurassic of Argentina, Hungary, Italy, Portugal, and most of North-West and central Europe, including as this one is, the United Kingdom. This specimen was found on the beaches of Charmouth in West Dorset.

Neither Apoderoceras nor Bifericeras donovani are strictly index fossils for the Taylori subzone, the index being Phricodoceras taylori. Note that Bifericeras is typical of the earlier Oxynotum Zone, and ‘Bifericeras’ donovani is doubtfully attributable to the genus. The International Commission on Stratigraphy (ICS) has assigned the First Appearance Datum of genus Apoderoceras and of Bifericeras donovani the defining biological marker for the start of the Pliensbachian Stage of the Jurassic, 190.8 ± 1.0 million years ago.

Apoderoceras, Family Coeloceratidae, appears out of nowhere in the basal Pliensbachian and dominates the ammonite faunas of NW Europe. It is superficially similar to the earlier Eteoderoceras, Family Eoderoceratidae, of the Raricostatum Zone, but on close inspection can be seen to be quite different. It is therefore an ‘invader’ and its ancestry is cryptic.

The Pacific ammonite Andicoeloceras, known from Chile, appears quite closely related and may be ancestral, but the time correlation of Pacific and NW European ammonite faunas is challenging. 

Even if Andicoeloceras is ancestral to Apoderoceras, no other preceding ammonites attributable to Coeloceratidae are known. We may yet find clues in the Lias of Canada. Apoderoceras remains present in NW Europe throughout the Taylori Subzone, showing endemic evolution. It becomes progressively more inflated during this interval of time, the adult ribs more distant, and there is evidence that the diameter of the macroconch evolved to become larger. 

At the end of the Taylori Subzone, Apoderoceras disappeared as suddenly as it appeared in the region, and ammonite faunas of the remaining Jamesoni Zone are dominated by the Platypleuroceras–Uptonia lineage, generally assigned (though erroneously) to the Family Polymorphitidae.

In the NW European Taylori Subzone, Apoderoceras is accompanied (as well as by the Eoderoceratid, B. donovani, which is only documented from the Yorkshire coast, although there are known examples from Northern Ireland) by the oxycones Radstockiceras (quite common) and Oxynoticeras (very rare), the late Schlotheimid, Phricoderoceras (uncommon) 

Note: P. taylori is a microconch, and P. lamellosum, the macroconch), and the Eoderoceratid, Tetraspidoceras (very rare). The lovely large specimen (macroconch) of Apoderoceras pictured here is likely a female. Her larger body perfected for egg production.

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. 

BREWERICERAS HULENENSE

Brewericeras hulenense (Anderson 1938) a fast-moving, nektonic (no idle floating here!) carnivorous ammonite from the Lower Cretaceous (Albian) of Haida Gwaii (aka Queen Charlotte Islands), British Columbia, Canada.

Ammonites belong to the class of animals called mollusks. More specifically they are cephalopods. and first appeared in the lower Devonian Period.

Cephalopods were an abundant and diverse group during the Paleozoic Era. This specimen is just over 12cm in length, a little under the average of 13.4cm. 

There are several localities in the archipelago of Haida Gwaii where Brewericeras can be found (six that I know of and likely plenty more!) 

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. 

This specimen was found on a trip a few years back done with the Vancouver Paleontological Society and a few of the members of some of the Island paleo groups. The preservation is quite remarkable!

Brewericeras are also found in Albian deposits in Svedenborgfjellet, Ulladalen, Norway (Cretaceous of Svalbard and Jan Mayen - så fin!) (77.7° N, 15.2° E: paleocoordinates 66.6° N, 13.6° E) and Matanuska-Susitna County, Alaska, 62.0° N, 147.7° W: paleocoordinates 57.3° N, 85.6° W (112.6 to 109.0 Ma.)

ATURIA: MIOCENE NAUTILOID

Aturia angustata, Lower Miocene, WA

This lovely Lower Miocene nautiloid is Aturia angustata collected on the foreshore near Clallam Bay, Olympic Peninsula, northwestern Washington. 

Aturia is an extinct genus of Paleocene to Miocene nautiloid within Aturiidae, a monotypic family, established by Campman in 1857 for Aturia (Bronn, 1838), and is included in the superfamily Nautilaceae (Kümmel,  1964).

There are seven living nautiloid species in two genera: Nautilus pompilius, N. macromphalus, N. stenomphalus, N. belauensis, and the three new species being described from Samoa, Fiji, and Vanuatu (Ward et al.). We have specimens of fossil nautiloids dating to the Turonian of California, and possibly the Cenomanian of Australia. There has also been a discovery of what might be the only known fossil of Allonautilus (Ward and Saunders, 1997), from the Nanaimo Group of British Columbia, Canada.

Aturia in the Collection of Rick Ross, VIPS

The exquisite shell preservation of many Nanaimo nautilids has opened up a lens into paleotemperatures and accurate Nitrogen isotope analyses. 

Nautilus and all other known Cretaceous through Paleogene nautiloids were shallow water carnivores. We may see their shells as beautiful bits of art and science today, but they were seen in our ancient oceans as small yet mighty predators. Preferring to dine on shrimp, crab, fish and on occasion, a friendly cousin nautiloid to two.

Aturia lived in cooler water in the Cenozoic, preferring it over the warmer waters chosen by their cousins. Aturia, are commonly found as fossils from Eocene and Miocene outcrops. That record ends with their extinction in the late Miocene. This was a fierce little beast with jaws packed with piranha-like teeth. They grew at least twice that of the largest known Nautilus living today. 

Aturia is characterized by a smooth, highly involute, discoidal shell with a complex suture and subdorsal siphuncle. The shell of Aturia is rounded ventrally and flattened laterally; the dorsum is deeply impressed. The suture is one of the most complex within the subclass Nautiloidea. Of all the nautiloids, he may have been able to go deeper than his brethren.

Nautiloids are known for their simple suturing in comparison to their ammonite cousins. This simplicity of design limited their abilities in terms of withstanding the water pressure experienced when several atmospheres below the sea. Nautiloids were not able to compete with their ammonite cousins in this regard. 

Instead of elaborate and complex sutures capable of withstanding the pressures of the deep, nautiloids have simpler sutures that would have them enfold on themselves and crush at depth.  

Aturia angustata; Rick Ross Collection

It has a broad flattened ventral saddle, narrow pointed lateral lobes, broad rounded lateral saddles, broad lobes on the dorso-umbilical slopes, and a broad dorsal saddle divided by a deep, narrow median lobe. 

The siphuncle is moderate in size and located subdorsally in the adapical dorsal flexure of the septum. Based on the feeding and hunting behaviours of living nautiluses, Aturia most likely preyed upon small fish and crustaceans. 

I've found a few of these specimens along the beaches of Clallam Bay and nearby in a local clay quarry. I've also seen calcified and chalcedony — microcrystalline quartz — agatized beauties of this species collected from river sites within the Olympic Peninsula range. In the bottom photos, you can see Aturia from Washington state and one (on the stand on the left) from Oregon, USA. These beauties are in the collections of the deeply awesome Rick Ross, Vancouver Island Palaeontological Society.

References: Ward, P; Haggart, J; Ross, R; Trask, P; Beard, G; Nautilus and Allonautilus in the Nanaimo Group, and in the modern oceans; 12th British Columbia Paleontological Symposium, 2018, Courtenay, abstracts; 2018 p. 10-11

HIGHLANDS OF ICELAND: AURORA

The Northern Lights over a sea of wildflowers in the marsh near Landmannalaugar, part of the Fjallabak Nature Reserve in the Highlands of Iceland.

Landmannalaugar is at the northern tip of the Laugavegur hiking trail that leads through natural geothermal hot springs and an austere yet poetically beautiful landscape. 

Here, you can see the Northern Lights play through the darkness of a night sky without light pollution and bask in the raw geology of this rugged land.

The Fjallabak region takes its name from the numerous wild and rugged mountains with deeply incised valleys, which are found there. 

The topography of the Torfajokull, a central volcano found within the Fjallabak Nature Reserve, is a direct result of the region being the largest rhyolite area in Iceland and the largest geothermal area (after Grimsvotn in Vatnajokull).

The Torfajokull central volcano is an active volcanic system but is now in a declining fumarolic stage as exemplified by numerous fumaroles and hot springs. The hot pools at Landmannalaugar are but one of many manifestations of geothermal activity in the area, which also tends to alter the minerals in the rocks, causing the beautiful colour variations from red and yellow to blue and green, a good example being Brennisteinsalda. Geologists believe that the Torfajokull central volcano is a caldera, the rim being Haalda, Suðurnamur, Norður-Barmur, Torfajokull, Kaldaklofsfjoll and Ljosartungur.

The bedrock of the Fjallabak Nature Reserve dates back 8-10 million years. At that time the area was on the Reykjanes – Langjokull ridge rift zone. 

The volcano has been most productive during the last 2 million years, that is during the last Ice Age Interglacial rhyolite lava (Brandsgil) and sub-glacial rhyolite (erupted under ice/water, examples being Blahnukur and Brennisteinsalda are characteristic formations in the area. 

To the north of the Torfajokull region, sub-glacial volcanic activity produced the hyaloclastites (Moberg) mountains, such as Lodmundur and Mogilshofdar.

On March 19, 2021, a volcanic eruption started in the Geldingadalir valley at the Fagradalsfjall mountain on the Reykjanes peninsula, South-West Iceland. The volcano is situated approximately 30 km from the country’s capital city, Reykjavík. The eruption is ongoing and the landscape in the valley and its surrounding area is constantly changing as a result.

Prior to the eruptive display earlier this year, volcanic activity over the past 10.000 years has been restricted to a few northeast-southwest fissures, the most recent one, the Veidivotn fissure from 1480, formed Laugahraun (by the hut at Landmannalaugar), Namshraun, Nordurnamshraun, Ljotipollur and other craters which extend 30 km, further to the north Eruptions in the area tend to be explosive and occur every 500 – 800 years, previous known eruptions being around AD 150 and 900.

KILLER WHALES OF THE PACIFIC: KEET MAX'INUX

One of the iconic animals of the Pacific Northwest are Orca or Killer Whales — Keet in Lingit. Keet-Shaa-gooon' — our ancestors. These playful giants hunt and play in our local waters and all the oceans of the world.

This past week, there has been a pod hunting and playing in the waters near where I am visiting on Vancouver Island. It is wonderful and a wee bit unusual to see them so long in the same hunting grounds. This partially due to their normal hunting behaviour but definitely impacted by the relentless roar of the motors of whale-watching boats.

I do like folk taking an interest in our wildlife. We are more likely to work to protect them if we get to know them. But hunting down a decent meal, courting a mate and rearing your young are challenging with all that racket going on. Imagine trying to cook dinner, play catch with your kid or make love to your partner with half a dozen looky-loos on a hovercraft watching your every move. A bit of attention is flattering but at some point that becomes creepy. 

And yes, whale watchers are meant to keep a healthy distance but that was certainly not the case with the crowd of boats this week. 

Not surprising then that the whales try to dodge the relentless spectators — expending energy on avoiding us instead of on the business of being whales... hunting, eating, rearing, mating. Sometimes we forget ourselves and enjoy wildlife to our own amusement not realizing the impact we have.

Orca are toothed whales who hunt our waters for fish, squid, birds and aquatic mammals. They are the largest member of the Dolphin family who hunt and live amongst their family groups or pods. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, orca are known as max̱'inux̱. I do not know the word for orca in the language of the Quw'utsun Cowichan First Nation whose shores they are swimming near this week. 

These large marine mammals are easily distinguished by their black-and-white colouration, large dorsal fin and a sleek, streamlined body. You can often get a peek at their top fin and just enough of their distinctive white eye patch to identify them from a distance.

Up close, their colouring is equally lovely. When I was little, a few resident orcas would come up to our float house and rub up against the side to give themselves a good scritch. We used to offer to help them with this by lowering a deck broom and rubbing it along them. They would roll around playfully and seemed to enjoy it much the same way dogs and cats appreciate a good scratch. 

They show curiosity and intelligence when they look at you and understand that your intention was to help not hurt when the broom was offered. One of them did give the broom a gentle nibble and carried it off a ways but very politely returned it a few minutes later. 

Across their back and along their pectoral flippers is a nice glossy black, The exception is their saddle, a wee patch of greyish white just behind their dorsal fin.  

Whales breathe through their nostril or blowhole that sits in the centre of their forehead. The blow of mist you see in the photo above is this fellow breathing and pushing air out through his blowhole and some seawater along with it. 

Killer whales have a white patch under their heads (lower jaw), under each fluke and a patch along their rear edge as you move towards the tail. While these patches of white make them easier for us to see and identify them, they act as camouflage to those they are hunting in the water.

Their large bodies are streamlined (hydrodynamic), like a submarine, for moving through the water. Whales have flukes or a tail used for swimming. The flukes are moved in an up-and-down motion to accelerate. The dorsal fin acts like the keel of a boat; it keeps the whale from rolling side to side while swimming. They have pectoral flippers just behind the head. These pectoral flippers are used for steering, turning, and stopping.

Live in coastal and offshore waters; resident pods may frequent localized waterways (bays, sounds, etc.) whereas transient pods tend to cover more extensive, varied areas.

An extended clan of orcas, known as the Southern Resident Orca community, socialize and forage in the inland waters of Washington State and British Columbia. The population grows and lessens in relation to the overall Chinook salmon abundance. It may have been this pod that were playing off our shores this week. They are certainly in the neighborhood on and off.

Females (cows) reach reproductive maturity quite late in life at around 14 to 15 years. They give birth every three to ten years, following a 17-month pregnancy. In our local waters, these young join the pod and stay together their whole lives.

At birth, the 2.6 m long calves arrive able to swim and dive and grow quickly feasting on their mothers' milk for the first year of their lives. 

The newborns stay close to mamma, feeding and learning from her and from the close-knit members of the pod. Over the course of their lives, these newborns will grow from 120 to 160 kg up to 3,600 to 7,250 kg.

Like all dolphins, orcas use sophisticated biological sonar, called echolocation. Echolocation enables them to locate and discriminate objects underwater. The vocalizations within whale communities vary and each are different from those in other communities. The calls also bring the pods together over large areas of water when it is not possible for the whales to see each other.

When all goes well, orcas live to be a ripe old age. Some males have been known to live into their 40s and perhaps up to 60+ years old. Females have been known to live up to 90+ years old.

DANCING ATOMS: AURORA BOREALIS

If you live in the northern hemisphere, you stand a very good chance of seeing the aurora borealis this evening. We had a spectacular showing last night. Their glorious dancing lights will be most visible from 11PM-4AM PST with their brilliance tapering off over the next few days.

Even with a fair bit of light pollution, you can see the colours quite clearly. Tonight's best showing is in the late afternoon to early evening. I am excited to see what we will see. 

The Earth has a magnetic field with north and south poles. The lights we see are the result of severe storms that push protons past their normal threshold around these two polar regions.  

The magnetic field of the Earth is surrounded by the magnetosphere which keeps most of the particles from the Sun from hitting the Earth. Some of these particles from the solar wind enter the atmosphere at one million miles per hour. The auroras occur when highly charged electrons from the solar wind interact with elements in the Earth's atmosphere and become trapped in the Earth's magnetic field. 

We see them as an undulating visual field of red, yellow, green, blue and purple dancing high in the Earth's atmosphere — about 100 to 400 kilometres above us. The green is the result of millions of oxygen atoms dancing like gleeful children as they decay back to their original state. 

The red is also caused by oxygen atoms but because those atoms are higher up in the atmosphere we register much of their vivid colour as green or reddish-green because of our poorly developed eyesight and lower red light emissions. 

Nitrogen atoms are a bit more standoffish. They get in on the action but only if the storm winds are very strong as it takes quite a hard hit to excite them. 

If you have been in the quiet northern regions for an aurora storm, you can hear their clapping sounds. On cold, clear nights, with light wind, a temperature inversion can form. This happens when a layer of relatively warm air creates a blanket over a shallow layer of cold air. 

Solar winds excite the atoms in the inversion layer, with opposite charges building up in the colder layer near the ground. When the aurora increases in intensity, geomagnetic disturbances travel down through the atmosphere causing the two layers to spark. 

We hear that electric discharge or spark as a click, click, click, clapping or banging sound. 

All science aside, what we see from these rare energetic interactions is one of the most beautiful of all-natural phenomena — Earth's polar lights, the aurora borealis in the north and the aurora australis, near the south pole. Vancouver had a wonderful surprise viewing a few weeks ago and tonight looks like it will provide another. 

The aurora borealis is best viewed in the north, of course, and many of my relatives have a bird's-eye view. To the Tlingit First Nation of Alaska, the aurora is Gis'óok. In Norway, the aurora is Nordlys — and by any name, spectacular. 

AURORA CAM

Explore.org have a live Aurora Cam and a ton of others that are equally interesting. To view, visit their site at: https://explore.org/livecams/zen-den/northern-lights-cam / Aurora Watch: https://auroraforecast.com/

Interested to learn more about the Sound of the Aurora? Give Meteorologist Michael Karow's thoughts a gander: https://weatherology.com/trending/articles/Sound-Aurora.html

FOSSIL FISHAPODS OF CANADA'S FAR NORTH

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!

SPIRALLING BEAUTY: TURRITELLA

Gastropods, or univalves, are the largest and most successful class of molluscs. They started as exclusively marine but have adapted well and now their rank spends more time in freshwater than in salty marine environments.

Many are marine, but two-thirds of all living species live in freshwater or on land. Their entry into the fossil record goes all the way back to the Cambrian.

Slugs and snails, abalones, limpets, cowries, conches, top shells, whelks, and sea slugs are all gastropods. They are the second-largest class of animals with over 60,000–75,000 known living species. The two beauties you see here are Turritella, a genus of medium-sized sea snails with an operculum, marine gastropod mollusks in the family Turritellidae. They hail from the Paris Basin and have tightly coiled shells, whose overall shape is basically that of an elongated cone. The name Turritella comes from the Latin word turritus meaning "turreted" or "towered" and the diminutive suffix -ella.

Many years ago, I had the pleasure of collecting in the Paris Basin with a fellow named Michael. I had stalked the poor man from Sunday market to Sunday market, eventually meeting up with him in the town of Gordes. He graciously shared his knowledge of the local fossil localities from the hills south of Calais to Poitiers and from Caen to the Rhine Valley, east of Saarbrücken. I deeply regret losing my notebook from that trip but cherish the fossils and memories.

The Paris Basin has many fine specimens of gastropods. These molluscs were originally sea-floor predators, though they have evolved to live happily in many other habitats. Many lines living today evolved in the Mesozoic. The first gastropods were exclusively marine and appeared in the Upper Cambrian (Chippewaella, Strepsodiscus). By the Ordovician, gastropods were a varied group present in a variety of aquatic habitats. Commonly, fossil gastropods from the rocks of the early Palaeozoic era are too poorly preserved for accurate identification. Still, the Silurian genus Poleumita contains fifteen identified species.

Most of the gastropods of the Palaeozoic belong to primitive groups, a few of which still survive today. By the Carboniferous, many of the shapes we see in living gastropods can be matched in the fossil record, but despite these similarities in appearance the majority of these older forms are not directly related to living forms. It was during the Mesozoic era that the ancestors of many of the living gastropods evolved.

In rocks of the Mesozoic era, gastropods are more common as fossils and their shells often very well preserved. While not all gastropods have shells, the ones that do fossilize more easily and consequently, we know a lot more about them. We find them in fossil beds from both freshwater and marine environments, in ancient building materials and as modern guests of our gardens.

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

BLADDER-BEARERS: HOODED SEALS

If you frequent the eastern coast of North America north of Maine to the western tip of Europe, along the coast of Norway near Svalbard you may have glimpsed one of their chubby, dark silver-grey and white residents. 

Hooded seals, Cystophora cristata, are large phocid seals in the family Phocidae, who live in some of the chilliest places on Earth, from 47° to 80° N in latitude. 

These skilled divers are mainly concentrated around Bear Island, Norway, Iceland, and northeast Greenland. 

In rare cases, we find them in the icy waters in Siberia. They usually dive depths of 600 m (1,968 ft) in search of fishy treats but can go as deep as 1000 m (3,280 ft) when needed. That is deep into the cold, dark depths of our oceans. Sunlight entering the sea may travel as deep as 1,000 m (3,280 ft) under the right conditions, but there is rarely any significant light beyond 200 meters (656 ft). This is the dark zone and the place we find our bioluminescent friends. 

Hooded seals have a sparse fossil record. One of the first fossils found was a Pliocene specimen from Anvers, Belgium discovered in 1876. In 1983 a paper was published claiming there were some fossils found in North America thought to be from Cystophora cristata. Of the three accounts, the most creditable discovery was from a sewer excavation in Maine, the northeasternmost U.S. state, known for its rocky coastline, maritime history and nature areas like the granite and spruce islands of Acadia National Park. A scapula and humeri were found among other bones and thought to date to the post-Pleistocene. 

Of two other accounts, one was later reassigned to another species and the other left unsolved. (Folkow, et al., 2008; Kovacs and Lavigne, 1986; Ray, 1983)

The seals are typically silver-grey or white in colour, with black spots that vary in size covering most of the body. 

Hooded seal pups are known as, Blue-backs as their coats are blue-grey on the back with whitish bellies, though this coat is shed after 14 months of age when the pups moult.

FIRST NATION, INUIT, METIS, MI'KMAQ L'NU

In the Kwak̓wala language of the Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, seal are known as migwat — and fur seals are known as x̱a'wa.

Hooded seals live primarily on drifting pack ice and in deep water in the Arctic Ocean and North Atlantic. Although some drift away to warmer regions during the year their best survival rate is in colder climates. They can be found on four distinct areas with pack ice: near Jan Mayen Island, northeast of Iceland; off Labrador and northeastern Newfoundland; the Gulf of St. Lawrence; and the Davis Strait, off midwestern Greenland. 

The province of Newfoundland and Labrador is home to the Inuit, the Innu, the Mi'kmaq L'nu and the Southern Inuit of NunatuKavut, formerly the Labrador Inuit-Metis. The Hooded Seals that visit their traditional territory were a welcome source of food and clothing. In Mi'kmaw, the language spoken in Mi'kma'ki, the territory of the Mi'kmaq L'nu, the word for seal is waspu.

HOODED SEAL HABITAT

Males are localized around areas of complex seabeds, such as Baffin Bay, Davis Strait, and the Flemish Cap. Females concentrate their habitat efforts primarily on shelf areas, such as the Labrador Shelf. 

Females reach the age of sexual maturity between two and nine years old and it is estimated that most females give birth to their first young at around five years of age. Males reach sexual maturity a little later around four to six years old but often do not mate until much later. Females give birth to one young at a time through March and April. The gestation period is 240 to 250 days. 

Blue-back, Hooded Seal Pup

During this time the fetus, unlike those of other seals, sheds its lanugo — a covering of fine soft hair that is replaced by thicker pelage — in the uterus. 

These young are precocious and at birth are able to move about and swim with ease. They are independent and left to fend for themselves immediately after they have been weaned.

Hooded seals are known to be a highly migratory species that often wander long distances, as far west as Alaska and as far south as the Canary Islands and Guadeloupe. 

Prior to the mid-1990s, hooded seal sightings in Maine and the east Atlantic were rare but began increasing in the mid-1990s. From January 1997 to December 1999, a total of 84 recorded sightings of hooded seals occurred in the Gulf of Maine, one in France and one in Portugal. 

From 1996 to 2006, five strandings and sightings were noted near the Spanish coasts in the Mediterranean Sea. There is no scientific explanation for the increase in sightings and range of the hooded seal.

Cystophora means "bladder-bearer" in Greek and pays homage to this species' inflatable bladder septum on the heads of adult males. The bladder hangs between the eyes and down over the upper lip in a deflated state. 

The hooded seal can inflate a large balloon-like sac from one of its nostrils. This is done by shutting one nostril valve and inflating a membrane, which then protrudes from the other nostril. 

I was thinking of Hooded seals when contemplating the nasal bladders of Prosaurolophus maximum, large-headed duckbill dinosaurs, or hadrosaurid, in the ornithischian family Hadrosauridae. Perhaps both species used these bladders in a similar manner — to warn predators and attract mates.

Hooded seals are known for their uniquely elastic nasal cavity located at the top of their head, also known as the hood. Only males possess this display-worthy nasal sac, which they begin to develop around the age of four. The hood begins to inflate as the seal makes its initial breath prior to going underwater. It then begins to repetitively deflate and inflate as the seal is swimming. 

The purpose of this is acoustic signaling. It occurs when the seal feels threatened and attempt to ward off hostile species when competing for resources such as food and shelter. It also serves to communicate their health and superior status to both other males and females they are attempting to attract. 

In sexually mature males, a pinkish balloon-like nasal membrane comes out of the left nostril to further aid it in attracting a mate. This membrane, when shaken, is able to produce various sounds and calls depending on whether the seal is underwater or on land. Most of these acoustic signals are used in an acoustic situation (about 79%), while about 12% of the signals are used for sexual purposes.

References: Ray, C. 1983. Hooded Seal, Cystophora cristata: Supposed Fossil Records in North America. American Society of Mammalogists, Vol. 64 No. 3: 509-512; Cystophora cristata, Hooded Seal", 2007; "Seal Conservation Society", 2001; Kovacs and Lavigne, 1986.

Mi'kmaq Online Dictionary: https://www.mikmaqonline.org/servlet/dictionaryFrameSet.html?method=showCategory&arg0=animal

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!

CANADA'S GREAT BEARS: TLA'YI

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

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

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

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

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

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

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

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

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

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

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

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

Kermode or Spirit Bear, Ursus americanus kermodei

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

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

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

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

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

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

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

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

DARWIN: A TASTE FOR STUDIES

Chelonia. Schildkröten by Ernst Haeckel, 1904

Care for some tarantula with that walrus? No? how about some Woolly mammoth?

While eating study specimens is not de rigueur today, it was once common practice for researchers in the 1700-1880s. 

The English naturalist, Charles Darwin belonged to an elite men's club dedicated to tasting exotic meats. In his first book, Darwin wrote almost three times as much about dishes like armadillo and tortoise urine as he did on the biogeography of his Galapagos finches. 

From his great love of gastronomy, I am surprised any of his tasty specimens made it back from his historic voyage on the HMS Beagle — particularly the turtles.

One of the most famous scientific meals occurred one Saturday evening on the 13th of January, 1951. This was at the 47th Explorers Club Annual Dinner (ECAD) when members purportedly dined on a frozen woolly mammoth. 

Commander Wendell Phillips Dodge was the promotor of the banquet. He sent out press notices proclaiming the event's signature dish would be a selection of prehistoric meat. Whether Dodge did this simply to gain attendees or play a joke remains a mystery. 

The prehistoric meat was supposedly found at Woolly Cove on Akutan in the Aleutians Islands of Alaska, USA, by the eminent polar explorers' Father Bernard Rosecrans Hubbard, American geologist, explorer sometimes called the Glacier Priest, and polar explorer Captain George Francis Kosco of the United States Navy.

Fried Tarantula & Goat Eyeballs

This much-publicized meal captured the public’s imagination and became an enduring legend and source of pride for the Club, popularizing an annual menu of exotics that continues today. The Club is well-known for its notorious hors d’oeuvres like fried tarantulas and goat eyeballs as it is for its veritable whose who of notable members — Teddy Roosevelt, Neil Armstrong, Buzz Aldrin, Roy Chapman Andrews, Thor Heyerdahl, James Cameron.

The Yale Peabody Museum holds a sample of meat preserved from the 1951 meal, interestingly labelled as a South American Giant Ground Sloth, Megatherium, not Mammoth. The specimen of meat from that famous meal was originally designated BRCM 16925 before a transfer in 2001 from the Bruce Museum to the Yale Peabody Museum of Natural History (New Haven, CT, USA) where it gained the number YPM MAM 14399.

The specimen is now permanently deposited in the Yale Peabody Museum with the designation YPM HERR 19475 and is accessible to outside researchers. The meat was never fixed in formalin and was initially stored in isopropyl alcohol before being transferred to ethanol when it arrived at the Peabody Museum. DNA extraction occurred at Yale University in a clean room with equipment reserved exclusively for aDNA analyses.

In 2016, Jessica Glass and her colleagues sequenced a fragment of the mitochondrial cytochrome-b gene and studied archival material to verify its identity, which if genuine, would extend the range of Megatherium over 600% and alter views on ground sloth evolution. 

Mammoth, Megatherium — Green Sea Turtle

Their results showed that the meat was not Mammoth or Megatherium, but a bit of Green Sea Turtle, Chelonia mydas. So much for elaborate legends. The prehistoric dinner was likely meant as a publicity stunt. 

Glass's study emphasizes the value of museums collecting and curating voucher specimens, particularly those used for evidence of extraordinary claims. Not so long before Glass et al. did their experiment, a friend's mother (and my kayaking partners) served up a venison steak from her freezer to dinner guests in Castlegar that hailed from 1978. Tough? Inedible? I have it on good report that the meat was surprisingly divine.

Reference: Glass, J. R., Davis, M., Walsh, T. J., Sargis, E. J., & Caccone, A. (2016). Was Frozen Mammoth or Giant Ground Sloth Served for Dinner at The Explorers Club?. PloS one, 11(2), e0146825. https://doi.org/10.1371/journal.pone.0146825

Image: Chelonia. Schildkröten by Ernst Haeckel, 1904, Prints & Photographs Division, Library of Congress, LC-DIG-ds-07619.

Join the Explorer's Club

Fancy yourself an explorer who should join the club? Here is a link to their membership application. The monied days of old are still inherent, but you will be well pleased to learn you can now join for as little as $50 US.

Link: https://www.explorers.org/wp-content/uploads/Membership-Application_2021-11-19.pdf

LOWER LIAS LYTOCERAS

A superbly prepped and extremely rare Lytoceras (Suess, 1865) ammonite found as a green ammonite nodule by Matt Cape in the Lower Lias of Dorset. 

Lytoceras are rare in the Lower Lias of Dorset — apart from the Belemnite Stone horizon — so much so that Paul Davis, whose skilled prep work you see here, initially thought it might be a Becheiceras hidden within the large, lumpy nodule. 

One of the reasons these lovelies are rarely found from here is that they are a Mediterranean Tethyian genus. The fossil fauna we find in the United Kingdom are dominated by Boreal Tethyian genera. 

We do find Lytoceras sp. in the Luridum subzone of the Pliensbachian showing that there was an influx of species from the Mediterranean realm during this time. This is the first occurrence of a Lytoceras that he has ever seen in a green nodule and Paul's seen quite a few. 

This absolutely cracking specimen was found and is in the collections of the awesome Matt Cape. Matt recognized that whatever was hidden in the nodule would take skilled and careful preparation using air scribes. Indeed it did. It took more than five hours of time and skill to unveil the lovely museum-worthy specimen you see here. 

We find Lytoceras in more than 1,000 outcrops around the globe ranging from the Jurassic through to the Cretaceous, some 189.6 to 109.00 million years ago. Once this specimen is fully prepped with the nodule material cut or scraped away, you can see the detailed crinkly growth lines or riblets on the shell and none of the expected coarse ribbing. 

Lytoceras sp. Photo: Craig Chivers

If you imagine running your finger along these, you would be tracing the work of decades of growth of these cephalopods. 

While we cannot know their actual lifespans, but we can make a healthy guess. 

The nautilus, their closest living cousins live upwards of 20 years — gods be good — and less than three years if conditions are poor.

The flanges, projecting flat ribs or collars, develop at the edge of the mouth border on the animal's mantle as they grow each new chamber. 

Each delicate flange grows over the course of the ammonites life, marking various points in time and life stages as the ammonite grew. There is a large variation within Lytoceras with regards to flanges. They provide both ornamentation and strength to the shell to protect it from water pressure as they moved into deeper seas.

The concretion prior to prep

This distinctive genus with its evolute shells are found in the Cretaceous marine deposits of: 

Antarctica (5 collections), Austria (19), Colombia (1), the Czech Republic (3), Egypt (2), France (194), Greenland (16), Hungary (25), Italy (11), Madagascar (2), Mexico (1), Morocco (4), Mozambique (1), Poland (2), Portugal (1), Romania (1), the Russian Federation (2), Slovakia (3), South Africa (1), Spain (24), Tanzania (1), Trinidad and Tobago (1), Tunisia (25); and the United States of America (17: Alaska, California, North Carolina, Oregon).

We also find them in Jurassic marine outcrops in:

Austria (15), Canada (9: British Columbia), Chile (6), France (181), Germany (11), Greenland (1), Hungary (189), India (1), Indonesia (1), Iran (1), Italy (50), Japan (14), Kenya (2), Luxembourg (4), Madagascar (2), Mexico (1), Morocco (43), New Zealand (15), Portugal (1), Romania (5), the Russian Federation (1), Slovakia (1), Spain (6), Switzerland (2), Tunisia (11), Turkey (12), Turkmenistan (1), Ukraine (5), the United Kingdom (12), United States (11: Alaska, California) — in at least 977 known collections. 

References:

Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2008-05-07. Retrieved 2017-10-18.

Paleobiology Database - Lytoceras. 2017-10-19.

Systematic descriptions, Mesozoic Ammonoidea, by W.J Arkell, Bernhard Kummel, and C.W. Wright. 1957. Treatise on Invertebrate Paleontology, Part L. Geological Society of America and University of Kansas press.