Thursday, 16 July 2020

PARASAUROLOPHUS WALKERI OF ALBERTA

Holotype Specimen of P. walkeri, Royal Ontario Museum
Closer to home, we can find species of Parasaurolophus walkeri in the Dinosaur Park Formation of Alberta, Canada. 

The Dinosaur Park Formation is the uppermost member of the Belly River Group — also known as the Judith River Group, a major geologic unit in southern Alberta. 

It is an area rich in fossils. The formation contains dense concentrations of dinosaur skeletons, both articulated and disarticulated, often found with preserved remains of soft-tissues. Remains of other animals such as fish, turtles, and crocodilians, as well as plant remains, are also abundant. The formation has been named after Dinosaur Provincial Park, a UNESCO World Heritage Site where the formation is well-exposed in the badlands that flank the Red Deer River.

The Dinosaur Park Formation was deposited during the Campanian stage of the Late Cretaceous, between about 76.9 and 75.8 million years ago in what was an alluvial and coastal plain environment. It is bounded by the nonmarine Oldman Formation below and the marine Bearpaw Formation above.

The formation includes diverse and well-documented fauna including dinosaurs such as the horned Centrosaurus, Chasmosaurus, and Styracosaurus, fellow duckbills Gryposaurus and Corythosaurus, the mighty tyrannosaurid Gorgosaurus, and armoured Edmontonia, Euoplocephalus and Dyoplosaurus

Dinosaur Park Formation is interpreted as a low-relief setting of rivers and floodplains that became more swampy and influenced by marine conditions over time as the Western Interior Seaway transgressed westward. The climate was warmer than present-day Alberta, without frost, but with wetter and drier seasons. Conifers were apparently the dominant canopy plants, with an understory of ferns, tree ferns, and angiosperms.

Some of the less common hadrosaurs in the Dinosaur Park Formation of Dinosaur Provincial Park, such as Parasaurolophus, may represent the remains of individuals who died while migrating through the region. They might also have had a more upland habitat where they may have nested or fed. The presence of Parasaurolophus and Kritosaurus in northern latitude fossil sites may represent faunal exchange between otherwise distinct northern and southern biomes in Late Cretaceous North America. Both taxa are uncommon outside of the southern biome, where, along with Pentaceratops, they are predominant members of the fauna.

Photo: Holotype Specimen: The incomplete Parasaurolophus walkeri type specimen in the Royal Ontario Museum. Location: 43° 40′ 5.09″ N, 79° 23′ 40.59″ W. Shared by MissBossy.

Tuesday, 14 July 2020

HAREMS AND BLUEHEAD WRASSE

The Bluehead Wrasse, Thalassoma bifasciatum, live in coral reefs of the Atlantic Ocean. They range from the Caribbean Sea to the Gulf of Mexico. They are an interesting species in that they live in harems. 

When the male dies, one of the females transforms into a male and take control of the harem. It's a relatively quick takeover that happens just over a week. Taking control and exuding their maleness takes on a whole new meaning with Bluehead Wrasse. The males have a specific social system. Terminal phase males — which are the most aggressive and have the "highest" ranking among the males — and initial phase males — think horn-dog as they'll mate any chance they get in a larger group.  

When aggressive terminal phase males chase initial phase males, their colour changes to metallic green. Like flowers attracting bees, Bluehead Wrasse change colour to indicate their willingness to mate. When they are courting a female, Wrasse change to a soothing pinkish-grey (awe) and form black circles on their fins. It's the Wrassy equivalent to bring her a bouquet of flowers. Initial phase males, terminal phase males, and females all have the capability of reproducing. Tricky little bastards these Wrasse.

Monday, 13 July 2020

FLOUNDERS: BILATERAL SYMMETRY AND SHOOTING X'S

Flounders are a group of flatfish species. They are demersal fish, found at the bottom of oceans around the world. A few of their brethren call estuaries home. 

They undulate their bodies, darting from place to place, then resting on the bottom camouflaged by the muddy bottom. As a group, they belong to the families Achiropsettidae, Pleuronectidae, Paralichthyidae, and Bothidae (order Pleuronectiformes). 

Flounders are born with bilateral symmetry with an eye on each side. A few days later, they begin to lean to the side. The eye on their lower side slowly migrates so both eyes are on top. To make this work, their bodies undergo various changes in bones, nerve and muscular structure. Their undersides slowly lose colour — as who cares what colour your belly is if nobody's going to see it when you mate. But flounders face other pressures.

We complain about first world problems, but stressors in mating for our fishy friends are very real. If a genotypically female flounder is stressed during sexual development, she'll become phenotypically male — though he'll shoot all X's when it comes time to fertilize. 

Sunday, 12 July 2020

CAMPANIAN OF HOKKAIDO

A very beautiful Lower Campanian block from Haroto, Hokkaido, Japan. This specimen contains an ancient undersea world at a glance.

The beautiful block you see here was prepared, photographed and is in the collections of José Juárez Ruiz. In it, you can see a lovely Pseudoxybeloceras (Parasolenoceras) soyaense (143 mm), Polyptychoceras jimboi (134 mm), Polyptychoceras sp. (114 mm), Gaudryceras mite (48 and 45 mm), Gaudryceras tenuiliratum (Hirano, 1978) at (48 and 20 mm), and a wee fragment of wood (69 mm).

Matsumoto published on the ammonites from the Campanian (Upper Cretaceous) of northern Hokkaido back in 1984, in the Palaeontological Society of Japan Special Series Papers, Number #27.

This was my first look at the glorious fauna from northern Japan. The species and preservation are truly outstanding. Since then, many of the Japanese palaeontologists have made their way over to Vancouver Island, to look at ammonites, inoceramids and coleoid jaws from the Nanaimo Group and compare them to the Japanese species.

Rick Ross and Pat Trask, both of Courtenay on Vancouver Island, collaborated with Dr. Kazushige Tanabe and Yoshinori Hikida of Japan, to produce a wonderful paper in the Journal of Paleontology, 82 (2), 2008, pp 398-408, on Late Cretaceous Octobrachiate Coleoid Lower Jaws from the North Pacific Regions. They compared eight well-preserved cephalopod jaws from Upper Cretaceous (Santonian and Campanian) deposits of Vancouver Island, Canada, and Hokkaido, Japan. Seven of these were from Santonian to lower Campanian strata of the Nanaimo Group in the northeastern region of Vancouver Island. The eighth specimen was from Santonian strata of the Yezo Group in the Nakagawa area, northern Hokkaido, Japan. 

While they were collaborating on identifying coleoid jaws from the Comox Valley, Rick was visited twice by Dr. Kazushige Tanabe who was joined by his colleague Akinori Takahashi. Takahashi is an expert on temporal species-diversity changes in Japanese Cretaceous inoceramid bivalves.

They had the very great pleasure of visiting many fossil sites and seeing personal and museum collections. If you'd like to read Matsumoto's paper, here is the link: http://www.palaeo-soc-japan.jp/download/SP/SP27.pdf  I have a pdf copy of the Coleoid paper from Rick. It has very nice photos and illustrations, including a drawing of the holotypes of Paleocirroteuthis haggerti n. gen. and Paleocirroteuithis pacifica.

Here's a link to one of Takahashi's papers: https://bioone.org/journals/paleontological-research/volume-9/issue-3/prpsj.9.217/Diversity-changes-in-Cretaceous-inoceramid-bivalves-of-Japan/10.2517/prpsj.9.217.short

Saturday, 11 July 2020

MEET ANKYLORHIZA, APEX DOLPHIN

Back in the 1880s, a large fragmentary skull of an ancient toothed dolphin was described that would later be known as Ankylorhiza tiedemani

The newly named genus Ankylorhiza is derived from the Greek word "ankylo" meaning bound, stiff, or fused, and "rhiza", meaning root — meaning fused roots, and referring to the mostly single-rooted condition of the teeth — a surprisingly toothy grin for an early dolphin. 

We think of dolphins as the gentle, squeaky darlings of the ocean but back in the Oligocene, they were formidable predators. Picture a mug full of sharp teeth and a body designed for speed. Ankylorhiza tiedemani was the largest member of the Odontoceti, our toothed whale friends. 

More bits and pieces of this brute were unearthed in the 1970s and 1990s. We usually find just the skulls of our aquatic friends but the nearly complete skeleton that found its way to the Mace Brown Museum of Natural History at the College of Charleston included a well-preserved skull, the ribcage, most of the vertebral column and a lone flipper. These additional bits of the skeleton provided the information necessary to truly tease out this ancient tale. Together, the bones tell the story of a 4.8 m predator who would have diverged from baleen whales — but continued to evolve convergent similarities — about 35-36 million years ago. 

This beast of a dolphin hunted our ancient seas some 24 million years ago. He was a fast swimmer with a narrow tail stock, some added tail vertebra and a shorter humorous — upper arm bone — in his flippers. Some dolphins can exceed speeds of 50 km/h, a feat accomplished by thrusting the flukes while adjusting attack angle with their flippers. These movements are driven by robust axial musculature anchored to a relatively rigid torso consisting of numerous short vertebrae and controlled by hydrofoil-like flippers. 

Eocene skeletons of whales illustrate the transition from semiaquatic to aquatic locomotion, including the development of a fusiform body and reduction of hindlimbs, but the rarity of Oligocene whale skeletons has hampered efforts to understand the evolution of fluke-powered, but forelimb-controlled, locomotion. Modern whales and dolphins are superbly adapted for marine life, with tail flukes being a key innovation shared by all extant species. Did ancient dolphins have these modifications for speed? Most thought not. We have the benefit of modern species to make tentative comparisons but need ancient specimens to confirm the hypothesis. 

Kudos to Robert Boessnecker and team for their paper in the journal Current Biology. In it, they report a nearly complete skeleton of the extinct large dolphin Ankylorhiza tiedemani comb. n. from the Oligocene of South Carolina, previously known only from a partial rostrum. Its forelimb is intermediate in morphology between stem cetaceans and extant taxa, whereas its axial skeleton displays incipient rigidity at the base of the tail with a flexible lumbar region. 

The position of Ankylorhiza near the base of the odontocete radiation implies that several postcranial specializations of extant cetaceans, including a shortened humerus, narrow peduncle, and loss of radial tuberosity, evolved convergently in odontocetes and mysticetes. Craniodental morphology, tooth wear, torso vertebral morphology, and body size all suggest that Ankylorhiza was a macrophagous predator that could swim relatively fast, indicating that it was one of the few extinct cetaceans to occupy a niche similar to that of killer whales.

If you fancy a read, here's the reference:

Robert W. Boessenecker et al. Convergent Evolution of Swimming Adaptations in Modern Whales Revealed by a Large Macrophagous Dolphin from the Oligocene of South Carolina. Current Biology, published online July 9, 2020; doi: 10.1016/j.cub.2020.06.012

Friday, 10 July 2020

BOTTLENOSE DOLPHINS

These delightfully friendly and super smart fellows are Bottlenose dolphins. They are the most common members of the family Delphinidae, the family of oceanic dolphin. The genus is made up of three species: the bottlenose dolphin, Tursiops truncatus, the Indo-Pacific bottlenose dolphin, Tursiops aduncus, and the Burrunan dolphin, Tursiops australis

They are marine mammals who live in our world's oceans and breathe air at the surface, similar to humans. They have lungs, inhaling and exhaling through a blowhole at the top of their heads instead of a through their nose. They are social mammals and very playful. You may have seen them playing in the water, chasing boats or frolicking with one another. Humpback whales are fond of them and you'll sometimes see them hanging out together. 

Bottlenose dolphins are also choosy about who they spend time with. While they stick close to Mamma for the first three years of their lives, they like to spend time in close social groups with their friends. Males tend to choose to hang out with males resting, rubbing up against one another and being playful. Females tend to favour their female friends and their chosen quality time activity is often foraging for fish. They still move freely amongst all the members of their pod but do have favourites.

Dolphins are quite vocal, making a lot of interesting noises in the water. Dolphins engage with the world around them through sound. They squeak, squawk and use body language — leaping from the water while snapping their jaws and slapping their tails on the surface — to express themselves. 

They love to blow bubbles and will swim right up to you for a kiss and cuddle. I swam with dolphins many years ago down in the Bahamas. They are pretty fast in the water, reaching speeds of up to 35 kilometres per hour. Each individual dolphin has a signature sound, a whistle that is uniquely theirs. Dolphins use this whistle to tell one of their friends and family members from another.

Thursday, 9 July 2020

CERATITES NODOSUS

A lovely beast of an ammonite, Cératites nodosus, from the collections of the deeply awesome Ange Mirabet. This species is an extinct genus of nektonic marine carnivore from limestone deposits near Alsace on the Rhine River plain of northeastern France.

You can see the nice ceratitic suture pattern on this specimen with his smooth lobes and frilly saddles. The sutures would have increased the strength of the shell and allowed Ceratites (de Haan, 1825) to dive deeper, bearing the additional pressure of the sea in search of food.

Ammonite shells are made up predominantly of calcium carbonate in the form of aragonite and proteinaceous organic matrix or conchiolin arranged in layers: a thin outer prismatic layer, a nacreous layer and an inner lining of prismatic habitat. While their outer shells are generally aragonite, aptychus — those hard shelly plates you see — are distinct as they are composed of calcite.

These ammonites lived in open shallow, to subtidal and basinal environments some 247 to 221 million years ago. We've found them, thus far, in just over forty collections from nearly ninety fossil deposits around the globe. Fossils of species have been found in the Triassic of Austria, Canada, China, France, Germany, Hungary, India, Israel, Italy, Pakistan, Poland, Russia, Thailand, Turkey and the United States.

The parent taxon is Ceratitinae according to E. T. Tozer 1981. That's our own Tim Tozer, one of the great knights-errant of the Triassic timescale. Born a Brit but spent his life exploring the wilds of Canada and the Arctic Archipelago. It was Tim Tozer and Norm Silberling who published the classic milestones of the Triassic timescale, "Biostratigraphic Classification of the Marine Triassic in North America, Geological Society of America, Special Paper 110." The Global Triassic: Bulletin 41 from the New Mexico Museum of Natural History and Science by Lucas and Spielmann honours them in their work. Collection of Ange Mirabet, Strasbourg, France.

Wednesday, 8 July 2020

OH, CORONICERAS!

This Jurassic ammonite is from an all but inaccessible site in Sayward, Bonanza Group, Vancouver Island. He's a Coroniceras with a truly marvellous keel.

By the time these ammonites were being buried in sediment, Wrangellia, the predominately volcanic terrane that now forms Vancouver Island and the Queen Charlotte Islands, had made its way to the northern mid-latitudes.

Within the basal part of the sequence, sedimentary beds are found interbedded with lapilli and crystal-tuffs. Here you'll see maroon tuffaceous sandstone, orange-grey sandstone, granule sandstone and conglomerate. Within them we find ammonites nestled in with gastropods and pelecypods. 

While the fossiliferous outcrop is quite small, the Bonanza group is much larger, estimated to be at least 1000 metres thick. The site is quite small and in an active logging area, so the window to collect was limited. The drive up the mountain was thrilling as there had just been heavy rains and the road was washed out and narrowed until it was barely the width of our wheelbase and then narrowed further to be just shy of the width of the vehicle — thrilling, to say the least. So scary that my passengers all got out as there was a high probability of going head-first over the edge. I navigating by some handwritten field notes and a wee map on a paper napkin that should have read, "park at the bottom and hike up." Nope. We didn't park at the bottom and were halfway up the mountain before the road narrowed out. Too narrow to turn around, so the only way was up. 

Coroniceras with a sweet, sweet keel
Graham Beard from Qualicum Beach was the fellow who showed me the site and drew the wee map for me. I cannot recall everyone on the trip, but Perry Poon was there — he shot a video of the drive up that he described as thrilling. I've never seen it but would like to one day — and so was Patricia Coutts with her lovely Doberman. 

She and I had just done a trip up to Goldbridge where the cliff we were on had turned into a landslide into a ravine so she was feeling understandably cautious about the power of Mother Nature. Picture the angle, the hood of my jeep riding high and hiding what remained of the road beneath and a lovely stick shift that made you roll backwards a wee bit with every move to put it into gear. So, without being able to see the very narrow path beneath, I had to just keep going. Both Perry and Patricia helped with filling in the potholes so my tires would have something to grip. I bent the frame on the jeep heading up and had some explaining to do when I returned it to the car rental place. 

In the end, we found what we were looking for. Memekay yields a mix of ammonites, gastropods and bivalves. Many of them poorly preserved. It was a hell of a ride but well worth the effort as we found some great fossils and with them more information on the palaeontology and geology of Vancouver Island. Just look at the keel on this beauty.

Tuesday, 7 July 2020

SPOTTED CLEANER SHRIMP: FISH WASH

"Wash that for you, sir?" If you were a fish living in the warm turquoise waters off the coast of Bonaire in the southern Caribbean Sea, you may not hear those words, but you'd see the shrimp sign language equivalent. It seems Periclimenes yucatanicus or the Spotted Cleaner Shrimp are doing a booming business in the local reefs by setting up a Fish Wash service.

That's right, a Fish Wash. You'd be hard-pressed to find a terrestrial Molly Maid with two opposable thumbs as studious and hardworking as this wee marine beauty. You'll find them each day cleaning and snacking on a host of parasites. As many as twenty to thirty shrimp gather together to assemble a  highly-efficient marine cleaning station. They're even open to partnerships and mergers, partnering up with Cleaner Wrasse, or cleaner fish, for larger, high-end clients.

Spotted cleaner shrimp are about 2.5 cm long and have a delightful transparent body with telltale white and brown spots. Their legs, or chelae, are striped in purple, white and red. They live about 24 metres (or 79 ft) down on the seafloor in many of our planet's most beautiful waters. Aside from the Caribbean, they also enjoy setting up shop in the Bahamas, southern Florida and live as far south as Panama and Columbia. They are carnivorous crustaceans in the family, Palaemonidae.

This quiet marine mogul is turning out to be one of the ocean's top entrepreneurs. Keeping its host and diet clean and green, the spotted shrimp hooks up with the locals, in this case, local sea anemones and sets up a fish wash. Picture a car wash but without the noise and teenage boys. The signage posted is the shrimps' natural colouring which attracts fish from around the reefs. They sway back and forth to indicate that they are open for business.

Wash on, wash off.

Once within reach, the shrimp cleans the surface of the fish, giving the fish a buff and the shrimp its daily feed. This is good news for the shrimp, especially this time of year as they breed and brood their eggs in summer. 

After hatching, the larvae pass through a series of sadly, tasty planktonic stages before setting up a fish wash of their own. These cuties form a solid base for the oceanic food chain. Once they are older, they gain some protection from being eaten by their clients by a special signalling system that essentially shouts, "just here cooperation not as food." Here's to Periclimenes for keeping up the family business.

Thursday, 2 July 2020

HETEROPTERAN OF THE GREEN RIVER

A delightful Heteropteran collected this past year by Jim Barkley from Eocene exposures of the Green River Formation of Western Colorado. The specimen looks like he's been brushed as ink across rough watercolour paper. The Green River Formation boasts very fine detail in the preservation of the fossils found here. 

This was once the bottom of an extensive series of Eocene lakes. The fossils record which species called this area home and what the climate was like they lived in some 50 million years ago. It was warmer and wetter than that area today. Think temperate to sub-tropical, with temperatures ranging from 15 to 20 degrees Celsius. The Green River Formation has layers and layers of fine-grain sedimentary rock particularly abundant in beautifully preserved fossil fish, eleven species of reptiles including a 13.5ft crocodile, an armadillo-like mammal, Brachianodon westorum, bats, birds and other freshwater aquatic goodies.

Sunday, 28 June 2020

CRASPEDITES OF RUSSIA

This stunning block with the black matrix holds two lovely ammonoids found near the town of Rybinsk in the Yaroslavl region of Russia just northeast of Moscow. Interestingly, both Miss Russia 1998 and the first women in space hail from here, Anna Malova and Valentina Tereshkova respectively. Beyond bright, beautiful women, the area is home to some of the most interesting fossil specimens on the globe. 

You can see two of them here. The lovely larger ammonoid with the oil-in-water colouring is Craspedites okensis (d'Orbigny, 1945). Craspedites is an ammonoid cephalopod included in the Perisphinctaceae that lived during the Late Jurassic and Early Cretaceous, found in Canada, Greenland, Poland and Russia.

The genus Craspedites was first described by Aleksei Petrovich Pavlow in 1892. It is characterized by a small — up to about 5 cm in diameter — smooth, involute shell with simple ammonitic sutures. The whorl section is rounded with a smooth centre and small umbilicus exposing the dorsal portion of the inner whorls. Craspedites was thought to be restricted to the Upper Jurassic Tithonian until the discovery of a new species, C. sachsi, from the Berriasian of Russia (A. E. Igolnikov, 2012) named in honour of palaeontologist V.N. Sachs.

The smaller ammonite you see on the bottom of this block is Craspedites sp. from Jurassic deposits of the Volgian Stage, the zone subditus — 150 - 140.2 million years old. The photo credit belongs to the deeply awesome Emil Black. This block is in his personal collection. If you're interested in learning more about the ammonites from Russia, there is a publication from Ernst Gerold Westermann you may want to read, The Jurassic Ammonite Zones of the Soviet Union, Issue 223.

A. E. Igolnikov (2012). Craspedites (Vitaliites?) sachsi, a New Boreal Berriasian ammonite species of the North of Eastern Siberia (Nordvik Peninsula) Paleontological Journal. 46 (1): 12–15. Here's the link if you'd like to read it: 

Saturday, 27 June 2020

AMMONITES OF THE VOLGA REGION

The Heteromorph, Jaubertites (Audouliceras) renauxianum
A stunningly beautiful example of the heteromorph ammonite Jaubertites (Audouliceras) renauxianum (d'Orbigny, 1842) from the Volga region in Russia. The Volga region encompasses the drainage basin of the Volga River, the longest river in Europe, in central and southern European Russia. The area is well-known for the beautiful fossil assemblages found here.

These magnificent Jaubertites (Audouliceras) renauxianum heteromorph ammonites are often composites — built with exceptional artful skill from various partial specimens.

We sometimes see them cut in two symmetrical parts and glued into a matrix then doctored up a bit for sale. The practice is frowned upon both scientifically and commercially but continues as does the demand for these exceptional specimens. This beauty is in the collection of José Juárez Ruiz and is complete with some minor restorations. I love these chunky Jaubertites and particularly appreciate the beautiful oil in water colouring in the nacre.

The second photo here shows a lovely busy block of ammonites with Deshayesites volgensis (Sasonova, 1958), and Aconeceras (Sinzovia) trautscholdi (Sinzow. 1870) from Lower Cretaceous, Aptian, (120 - 112 MYA), deposits in the v. Shilovka, Ulyanovsk Region of Russia. This beauty is in the collections of Emil Black. While Emil has counselled me that there are some fundamental challenges with the interpretation of these faunal groups, I will share what is available from the current literature.

Aptian deposits near the Volga River between Ul'yanovsk and Saratov have been studied for more than a century. The area produces some of the most beautiful and sought after ammonite specimens in the world. I've never had the pleasure of collecting in this region but follow the literature and local collectors with enthusiastic interest. Looking at the specimens from here, I'm sure you can appreciate why.

Deshayesites volgensis & Aconeceras trautscholdi
The age of lower Aptian deposits was traditionally established based on changing ammonite assemblages of the family Deshayesitidae. The beauty you see to the right with the lovely ribbing and coloured from cream through to pink and blue is the hallmark species of this area.

But Deshayesitidae are not the only specimens found here. The vast array of heteromorphic ammonites  —  the Ancyloceratidae, inhabitants of relatively deep basins, has made it possible to propose a new scheme of ammonoid zonation in the lower Aptian epipelagic deposits of the Russian plate.

Many of the identified ancyloceratids were established here for the first time. The analysis of coexisting deshayesitids and heteromorphs enables a correlation of stratigraphic schemes for the monomorphic Deshayesitidae and heteromorphic Ancyloceratidae.

The described generic taxa and species are Volgoceratoides I. Michailova et Baraboshkin, gen. nov., V. schilovkensis I. Michailova et Baraboshkin, sp. nov., Koeneniceras I. Michailova et Baraboshkin, gen. nov., K. tenuiplicatum (von Koenen, 1902), K. rareplicatum I. Michailova et Baraboshkin, sp. nov.

In some sections of the Saratov Volga area, specifically in the central part of the Russian Platform, we find both offshore and nearshore lithofacies of the epicontinental Middle Russian Sea. Here we see simultaneous changes in ammonite and belemnite successions that speak to an environmental shift. The significant influence of anoxic events on faunal turnovers in marine communities is well-established. However, many studies are focused on the impact of anoxic conditions on benthic organisms, not on the hunter-gatherers living higher up in the sea column and food chain. For this reason, coeval changes in pelagic cephalopod assemblages remain relatively poorly studied and marginally understood.

Belemnites, represented by the late members of the family Oxyteuthididae, are common in the interval directly preceding the anoxic event, but totally disappear with the onset of the black shale deposition. We see a reduction in the shell size of the Deshayesites ammonites across the mudstone – black shale boundary (maximum shell diameter of adults reduces from ∼20 cm to 7–8 cm).

Some other ammonites become numerous (Sinzovia) within the black shale interval or show the first occurrence in it (Koeneniceras and Volgoceratoides). The diminishing of Deshayesites shell size during the early Aptian OAE may have been caused by palaeoenvironmental factors such as progressive warming and regional input of brackish water.

The significant influence of anoxic events on faunal turnovers in marine communities is well-established. However, many studies are focused on the impact of anoxic conditions on benthic organisms, not on the hunter-gatherers living higher up in the sea column. This means that coeval changes in pelagic cephalopod assemblages remain relatively poorly understood.

Photo: Jaubertites (Audoulicerasrenauxianum (d'Orbigny, 1842) collection of José Juárez Ruiz.
Photo: Deshayesites volgensis (Sasonova, 1958), and Aconeceras (Sinzovia) trautscholdi (Sinzow. 1870) collections of Emil Black. The diameter on the Deshayesites shown here is 70 mm.

Rogov, Mikhail & Shchepetova, Elena & Ippolitov, Alexei & Seltser, Vladimir & Mironenko, Aleksandr & Pokrovsky, Boris & Desai, Bhawanisingh. (2019). Response of cephalopod communities on abrupt environmental changes during the early Aptian OAE1a in the Middle Russian Sea. Cretaceous Research. 10.1016/j.cretres.2019.01.007.

E. Yu. Baraboshkin and I. A. Mikhailova. New Stratigraphic Scheme of the Lower Aptian in the Volga River Middle Courses. Stratigraphy arid Geological Correlation, Vol 10, No 6, 2002, pp 603-626 Translated from Stratigrafiy a Geologicheskaya Korrelyatsiya, Vol 10, No 6, 2002, pp 82-105

Friday, 26 June 2020

HETTANGIAN: TETHYAN AFFINITY

This Hettangian ammonite, Alsatites proaries, is a lovely example of the cephalopods cruising our ancient oceans at that time. Alsatites is an extinct genus of cephalopod belonging to the Ammonite subclass. They lived during the Early Jurassic, Hettangian till the Sinemurian and are generally extremely evolute, many whorled with a broad keel. Or, as described by one of my very young friends, he looks like a coiled snake you make in pottery class.

It is during the Hettangian that the smooth shelled ammonite genus Psiloceras first appears. They span the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma (million years ago). For my European friends, the Hettangian is the time span in which the marine limestone, shales and clay Lias of western Europe were deposited.

The Hettangian is an interesting little period of our history. It spans the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma (million years ago). For my European friends, the Hettangian is the time in which the marine limestone, shales and clay Lias of western Europe were deposited. In British Columbia, Canada, we see the most diverse middle and late Hettangian (Early Jurassic) ammonite assemblages in the Queen Charlotte Islands (Haida Gwaii), an archipelago about 50 km off British Columbia's northern Pacific coast. In total, 53 ammonite taxa are described of which Paradasyceras carteri, Franziceras kennecottense, Pleuroacanthites charlottensis, Ectocentrites pacificus and Curviceras haidae are new.

In general, North American Early Jurassic ammonites are of Tethyan affinity or endemic to the eastern Pacific. For this reason, a separate zonation for the Hettangian and Sinemurian of the Western Cordillera of North America was established. Taylor et al. (2001), wrote up and published on much of this early research though, at the time, very little Canadian information was included.

Longridge, L. M., et al. “Three New Species of the Hettangian (Early Jurassic) Ammonite Sunrisites from British Columbia, Canada.” Journal of Paleontology, vol. 82, no. 1, 2008, pp. 128–139. JSTOR, www.jstor.org/stable/20144175. Accessed 27 Jan. 2020.

Tozer, ET (Tim): Marine Triassic faunas of North America: Their significance for assessing plate and terrane movements. Geol Rundsch 71, 1077-1104 (1982). https://doi.org/10.1007/BF01821119

Danner, W. (Ted): Limestone resources of southwestern British Columbia. Montana Bur. Mines & Geol., Special publ. 74: 171-185, 1976.

Davis, G., Monger, JWH & Burchfiel, BC: Mesozoic construction of the Cordilleran “collage”, central British Columbia to central California. Pacific Coast Paleography symposium 2, Soc. Economic Paleontologists and Mineralogists, Los Angeles: 1-32, 1978.

Gibson, DW: Triassic rocks of the Rocky Mountain foothills and front ranges of northeastern British Columbia and west-central Alberta. Geol. Surv. Canada Bull. 247, 1975.

Photo: Alsatites proaries, Coll. Reiter, Neoammoniten, 30 July 2011, 19:26:10

Thursday, 25 June 2020

EXPLORING THE GSC COLLECTIONS

From years of field collecting, the drawers of the Geological Survey in Canada are filled to the brim. John Fam, Vice-Chair of the Vancouver Paleontological Society kindly lent me his photo from a recent field trip to the GSC.

Marine Triassic occurs on the North American Plate over a latitudinal spread of 46 degrees, from California to Ellesmere Island. At some intervals of time faunas on the Plate permit the discrimination of two or three provinces with distinctively different coeval faunas. The faunal differences are evidently related to paleolatitude and the provinces are designated LPL, MPL, HPL (low, mid, high paleolatitude). Nevada provides the diagnostic characters of the LPL province; northeastern British Columbia the MPL; the Sverdrup Basin the HPL. In the Lower Triassic and early Middle Triassic (Anisian), the distinction between the MPL and HPL provinces cannot be made. All three provinces are recognized in the Ladinian, Carnian and Norian deposits.

In the western tracts of the Cordillera, the part formed of suspect terranes, apparently allochthonous with respect to the North American Plate, marine faunas are known all the way from southern Alaska and Yukon to Mexico. Lower and Upper Triassic faunas from these terranes, including some which today are at 63 degrees north, have the characters of the LPL province.

Middle Triassic faunas from the terranes, as presently known, do not contribute significant data. In the terranes of the Western Cordillera, LPL faunas were now up to 3,000 km north of their counterparts on the American Plate. Through the fossil fauna assemblages, we can see this level of tectonic displacement.

Taking into account the faunas and the nature of the rocks, the Triassic palaeogeography is interpreted as a tectonically quiet west shore for the North American Plate, bordered by an open sea or ocean; then, well off-shore, a series of volcanic archipelagos shedding sediment into adjacent basins. Some were fringed or intermittently covered by coralline shoals and carbonate banks. Deeper basins were in between. The islands probably were within 30 degrees of the Triassic equator and extended offshore for about 5000 km, to the spreading ridge directly ancestral to the East Pacific Rise. The geography west of the spreading ridge was probably comparable.

Jurassic and later generation of crust at the ridge had driven some of the islands into the North American Plate; some probably to South America; others have gone west to Asia. Evidence is given that northern New Guinea, New Caledonia and New Zealand may have been at a north latitude of 30 degrees or more in the Triassic. The terranes now forming the Western Cordillera had probably amalgamated, and reached the North American Plate, before the end of the Jurassic.

At the end of the Rhaetian – part of the Triassic — most of the ammonites had died out. The Hettangian, a rather poorly understood 3 million year time interval followed the Triassic-Jurassic mass extinction event. During the Hettangian, the new or  Neoammonites developed quite quickly. Within a million years, a fairly large, diverse selection of genera and species had risen to fill the void. The gap created by the Triassic-Jurassic extinction event was re-filled and our ability to "read the rocks' to understand their continued movement through tectonic plate shifting recommenced.

Wednesday, 24 June 2020

NORTH AMERICAN MIDDLE TRIASSIC AMMONOIDS


Grambergia sp. Early Anisian (Middle Triassic) Ammonoid
In the early 1980s, Tim Tozer, Geological Survey of Canada was looking at the spread of marine invertebrate fauna in the Triassic of North America. In the western terranes of the Cordillera, marine faunas from southern Alaska and Yukon to Mexico are known from the parts that are obviously allochthonous with regard to the North American plates.

Lower and upper Triadic faunas of these areas, as well as some that are today up to 63 ° North, have the characteristics of the lower paleo latitudes. As far as is known, Middle Triadic faunas in these zones do not provide any significant data.

In the western Cordillera, these faunas of the lower paleo latitudes can be found up to 3,000 km north of their counterparts on the American plate. This indicates a tectonic shift of significant magnitude. There are marine triads on the North American plate over 46 latitudes from California to Ellesmere Island. For some periods, two to three different faunal provinces can be distinguished. The differences infaunal species are linked, not surprisingly, to their paleolatitude. They are called LPL, MPL, HPL (lower, middle, higher paleolatitude).

I had the opportunity to head to Nevada last year to look at the Triassic ammonoids and ichthyosaur remains in the West Humboldt Mountains. Nevada provides the diagnostic features of the lower (LPL); northeastern British Columbia that of the middle (MPL) and Sverdrup Basin, the large igneous province on Axel Heiberg Island and Ellesmere Island, Nunavut, Canada near the rifted margin of the Arctic Ocean, that of the higher paleolatitude (HPL).

A distinction between the provinces of the middle and the higher paleo-situations can not be made for the lower Triassic and lower Middle Triassic (anise). However, all three provinces can be seen in the deposits of Ladin, Kam and Nor.

In the early 2000s, as part of a series of joint UBC, VIPS and VanPS fossil field trips (and then Chair of the VanPS), I explored much of the lower faunal outcrops of northeastern British Columbia. It was my first time seeing many of British Columbia's Triassic outcrops. The Nevada faunal assemblages are a lovely match. The quality of preservation at localities like Fossil Hill in the Humboldt Mountains of Nevada, perhaps the most famous and important locality for the Middle Triassic (Anisian/Ladinian) of North America, is truly outstanding. Aside from sheer beauty and spectacular preservation, the ammonoids and belemnites are cosied up to some spectacular well-preserved ichthyosaur remains.

Tozer's interest in our marine invert friends was their distribution. How and when did certain species migrate, cluster, evolve — and for those that were prolific, how could their occurrence — and therefore significance — aide in an assessment of plate and terrane movements that would help us to determine paleolatitudinal significance. I share a similar interest but not exclusive to our cephalopod fauna. The faunal collection of all of the invertebrates holds appeal.

This broader group held an interest for J.P. Smith who published on the marine fauna in the early 1900s based on his collecting in scree and outcrops of the West Humboldt Mountains, Nevada. He published his first monograph on North American Middle Triassic marine invertebrate fauna in 1914.

N. J. Siberling from the US Geological Survey published on these same Nevada outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species. Both their works would inform what would become a lifelong piecing together of the Triassic puzzle for Tozer.

If one looks at the fauna and the type of sediment, the palaeogeography of the Triassic can be interpreted as follows: a tectonically calm west coast of the North American plate that bordered on an open sea; in the area far from the coast, a series of volcanic archipelagos delivered sediment to the adjacent basins. Some were lined or temporarily covered with coral wadding and carbonate banks. Deeper pools were in between. The islands were probably within 30 degrees of the triadic equator. They moved away from the coast up to about 5000 km from the forerunner of the East Pacific Ridge. The geographical situation west of the back was probably similar.

Jurassic and later generations of the crust from near the back have brought some of the islands to the North American plate; some likely to South America; others have drifted west, to Asia. There are indications that New Guinea, New Caledonia and New Zealand were at a northern latitude of 30 ° or more during the Triassic period.

Tuesday, 23 June 2020

NAPPING KOALA

Koala, Phasscolarctos cinereus, are truly adorable marsupials native to Australia. These cuddly "teddy bears" are not bears at all.

Koalas belong to a group of mammals known as marsupials. 

Fossil remains of Koala-like animals have been found dating back 25 million years. Some of the relatives of modern koalas were much larger, including the Giant Koala, Phascolarctos stirtoni

It should likely have been named the Robust Koala, instead of Giant, but this big boy was larger than modern koalas by about a third. Phascolarctos yorkensis, from the Miocene, was twice the size of the modern koalas we know today. Both our modern koalas and their larger relatives co-existed during the Pleistocene, sharing trees and enjoying the tasty vegetation surrounding them.

Monday, 22 June 2020

POKEY TACHYCLOSSIDAE

This pokey fellow is a Short-beaked Echidna, Tachyclossus aculeatus, which grows to about the size of an overweight cat. They are native to Australia and New Guinea. 

Echidnas are sometimes called spiny anteaters and belong in the family Tachyglossidae (Gill, 1872). They are monotremes, an order of egg-laying mammals. 

There are four species of echidnas living today. They, along with the platypus, are the only living mammals who lay eggs and the only surviving members of the order Monotremata. 

Superficially, they resemble the anteaters of South America and other spiny mammals like porcupines and adorable hedgehogs. They are usually a mix of brown, black and cream in colour. While rare, there have been several reported cases of albino echidnas, their eyes pink and their spines white. Echidnas have long, slender snouts that act as both nose and mouth for these cuties. The Giant Echidna we see in the fossil record had beaks more than double this size.  

Like the platypus, they are equipped with electro sensors, but while the platypus has 40,000 electroreceptors on its bill, the long-beaked echidna has only 2,000. The short-beaked echidna, which lives in a drier environment, has no more than 400 at the tip of its snout.

Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. Their ancestors were aquatic, but echidnas have adapted to life on land. Today, they weigh in at about 7 kg today but back in the Pleistocene, they were much larger. The Giant Echnida, Megalibwilia ramsayi was about 10% larger at 10 kg and Zaglossus hacketti was a whopping 30 kg. 

Fossil remains are relatively rare and sadly, incomplete, but they tell us potentially two other species of Echidna thriving in the Pleistocene. We also find Robust Echidna, Zaglossus robustus, in slightly older Miocene aged outcrops in a goldmine in Australia. The Giant Echnida's we find in the fossil record are relatives of the Long-Beaked Echidnas who live in New Guinea today.      

Sunday, 21 June 2020

INUKSUK: STONE SENTINELS

An inuksuk or inukshuk, pronounced ih-nook-suuk — the human-shaped stone cairns built by the Inuit, Iñupiat, Kalaallit, Yupik, and other peoples of the Arctic regions of northern Canada, Greenland, and Alaska. 

These rocky sentinels stand as helpful reference markers for navigation. 

Translated from Inuktitut, the word inuksuk means that which acts in the capacity of a human, combining inuk or person and suk, to substitute.

Saturday, 20 June 2020

KEUPPIA: UNCOVERING OCTOBRACHIA

A wonderful example of Keuppia levante (Fuchs, Bracchi & Weis, 2009), an extinct genus of octopus that swam our ancient seas 95 million years ago.

Keuppia is in the family Palaeoctopodidae, and one of the earliest representatives of the order Octopoda. These ancient marine beauties are in the class Cephalopoda making them relatives of our modern octopus, squid and cuttlefish.

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

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

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

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

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

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

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

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

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

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

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

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

Wednesday, 17 June 2020

FOSSIL PEARLS

One of my favourite pairs of earrings are a simple set of pearls. I have worn them pretty much every day since 2016 when I received them as a gift. What is it about pearls that makes them so appealing? I am certainly not alone in this. 

A simple search will show you a vast array of pearls being used for their ornamental value in cultures from all over the world. I suppose the best answer to why they are appealing is just that they are

If you make your way to Paris, France and happen to visit the Louvre's Persian Gallery, do take a boo at one of the oldest pearl necklaces in existence — the Susa necklace. It hails from a 2,400-year-old tomb of long lost Syrian Queen. It is a showy piece with three rows of 72 pearls per strand strung upon a bronze wire. 

A queen who truly knew how to accessorize

I imagine her putting the final touches of her outfit together, donning the pearls and making an entrance to wow the elite of ancient Damascus. The workmanship is superb, intermixing pure gold to offset the lustre of the pearls. It is precious and ancient, crafted one to two hundred years before Christ. Perhaps a gift from an Egyptian Pharaoh or from one of the Sumerians, Eblaites, Akkadians, Assyrians, Hittites, Hurrians, Mitanni, Amorites or Babylonian dignitaries who sued for peace but brought war instead. 

Questions, good questions, but questions without answers. So, what can we say of pearls? We do know what they are and it is not glamorous. Pearls form in shelled molluscs when a wee bit of sand or some other irritant gets trapped inside the shell, injuring the flesh. As a defensive and self-healing tactic, the mollusc wraps it in layer upon layer of mother-of-pearl — that glorious shiny nacre that forms pearls. 

They come in all shapes and sizes from minute to a massive 32 kilograms or 70 pounds. While a wide variety of our mollusc friends respond to injury or irritation by coating the offending intruder with nacre, there are only a few who make the truly gem-y pearls. These are the marine pearl oysters, Pteriidae and a few freshwater mussels. Aside from Pteriidae and freshwater mussels, we sometimes find less gem-y pearls inside conchs, scallops, clams, abalone, giant clams and large marine gastropods.

Pearls are made up mostly of the carbonate mineral aragonite, a polymorphous mineral — same chemical formula but different crystal structure — to calcite and vaterite, sometimes called mu-calcium carbonate. These polymorphous carbonates are a bit like Mexican food where it is the same ingredients mixed in different ways. Visually, they are easy to tell apart — vaterite has a hexagonal crystal system, calcite is trigonal and aragonite is orthorhombic.

As pearls fossilize, the aragonite usually gets replaced by calcite, though sometimes by vaterite or another mineral. When we are very lucky, that aragonite is preserved with its nacreous lustre — that shimmery mother-of-pearl we know and love.  

Molluscs have likely been making pearls since they first evolved 530 million years ago. The oldest known fossil pearls found to date, however, are 230-210 million years old. 

This was the time when our world's landmass was concentrated into the C-shaped supercontinent of Pangaea and the first dinosaurs were calling it home. In the giant ancient ocean of Panthalassa, ecosystems were recovering from the high carbon dioxide levels that fueled the Permian extinction. Death begets life. With 95% of marine life wiped out, new species evolved to fill each niche.  

While this is where we found the oldest pearl on record, I suspect we will one day find one much older and hopefully with its lovely great-great grandmother-of-pearl intact. 

Monday, 15 June 2020

IS THAT YOU, MAMMA?

This little cutie is an Antarctic fur seal pup with his Mamma. They belong to the species Arctocephalus gazella and are pinnipeds that live in dense colonies alongside King Penguins. These two call the South Georgia islands home, as do 95% of the world's population.  

Though a wee pup, he can already recognize her voice from all the other lovely Mammas in his busy, noisy colony. Little ones left on the rocky shores while their mother is out hunting will raise their heads and listen out to identity their mother's voice and vocal pitch over the loud calls of all the other busy Mammas and penguins from the colony. If you look closely, you can see his wee little ears. Antarctic fur seals, unlike some other seal species, have visible ears.  

Seal pups stay with their mother, relying on her lactation milk to help them fatten up and grow healthy and strong. For the first four months of their lives, their mother will feed them on her rich milk, then head out to sea to forage for food. Once she's back, she'll call out to him and then give him a good sniff upon their reunion, the final confirmation for both parties that the right match has been made. The interaction between mother and pup is tender and heartbreakingly sweet to watch. She'll only give birth to one pup (two is rare) each October to December. Pups are born with a sheen of fur and grow their waterproof fur during their first months of life. 

When this little fellow grows up, he'll dine on fish, birds (including his penguin pals), squid and krill. Krill are small crustaceans of the order Euphausiacea that look like tiny shrimp. They look similar and are both crustaceans but shrimp hail from the suborder Natantia, order Decapoda and their hearts are located in their heads. I know, right? 

Krill live in all the world's oceans and sadly for them, they make a handy and tasty snack. They form an important part of the oceanic food chain. The krill feed on phytoplankton and zooplankton and then larger animals feed on the krill. 

"Krill" is Norwegian for "small fry of fish." They are small, indeed. But tasty, nutritious and easy to catch. Once this little pinniped pup is out hunting on his own, krill will make up the majority of his adult diet. He'll need our help to make sure he gets a steady supply. Krill are one of the casualties of ocean acidification from climate change. Hopefully, we'll do better so that he can, too!

Sunday, 14 June 2020

PUFFIN ENJOYING A SNICK

This lovely fellow about to enjoy a tasty snack is a Puffin. 

Puffins hunt and munch on small fish, eels, herring, hake and capelin. Their diet varies according to their geographic location and what is in season. 

Puffins are any of three small species of alcids or auks in the bird genus Fratercula with a brightly coloured orange beak during the breeding season. 

Their sexy orange beaks shift from a dull grey to bright orange when it is time to attract a mate. While not strictly monogamous, most Puffins choose the same mate year upon year producing adorable chicks or pufflings (awe) from their mating efforts. 

Female Puffins produce one single white egg which the parents take turns to incubate over a course of about six weeks. Their dutiful parents share the honour of feeding the wee pufflings five to eight times a day until the chick is ready to fly. Towards the end of July, the fledgeling Puffins begin to venture from the safety of their parents and dry land. Once they take to the seas, mom and dad are released from duty and the newest members of the colony are left to hunt and survive on their own.

These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crevices among rocks or in burrows in the soil. Two species, the tufted puffin and horned puffin are found in the North Pacific Ocean, while the Atlantic puffin is found in the North Atlantic Ocean. This lovely fellow, with his distinctive colouring, is an Atlantic Puffin or "Sea Parrot" from Skomer Island near Pembrokeshire in the southwest of Wales. Wales is bordered by Camarthenshire to the east and Ceredigion to the northeast with the sea bordering everything else. It is a fine place to do some birding if it's seabirds you're after.

These Atlantic Puffins are one of the most famous of all the seabirds and form the largest colony in Southern Britain. They live about 25 years making a living in our cold seas dining on herring, hake and sand eels. 

Some have been known to live to almost 40 years of age. They are good little swimmers as you might expect, but surprisingly they are great flyers, too! They are hindered by short wings, which makes flight challenging but still possible with effort. Once they get some speed on board, they can fly up to 88 km an hour.

The oldest alcid fossil is Hydrotherikornis from Oregon dating to the Late Eocene while fossils of Aethia and Uria go back to the Late Miocene. Molecular clocks have been used to suggest an origin in the Pacific in the Paleocene. Fossils from North Carolina were originally thought to have been of two Fratercula species but were later reassigned to one Fratercula, the tufted puffin, and a Cerorhinca species. Another extinct species, Dow's puffin, Fratercula dowi,  was found on the Channel Islands of California until the Late Pleistocene or early Holocene.

The Fraterculini are thought to have originated in the Pacific primarily because of their greater diversity there; there is only one extant species in the Atlantic, compared to two in the Pacific. The Fraterculini fossil record in the Pacific extends at least as far back as the middle Miocene, with three fossil species of Cerorhinca, and material tentatively referred to that genus, in the middle Miocene to late Pliocene of southern California and northern Mexico.

Although there no records from the Miocene in the Atlantic, a re-examination of the North Carolina material indicated that the diversity of puffins in the early Pliocene was as great in the Atlantic as it is in the Pacific today. This diversity was achieved through influxes of puffins from the Pacific; the later loss of species was due to major oceanographic changes in the late Pliocene due to closure of the Panamanian Seaway and the onset of severe glacial cycles in the North Atlantic.

Friday, 12 June 2020

OLENELLUS OF THE EAGER FORMATION

Olenellus is an extinct genus of redlichiid trilobites, with species of average size (about 5 centimetres or 2.0 inches long). It lived during the Botomian and Toyonian stages, Olenellus-zone, 522 to 510 million years ago, in what is currently North-America, part of the paleocontinent Laurentia.

Olenellus are a genus of trilobites — extinct arthropods  — common in but restricted to Early Cambrian rocks some 542 million to 521 million years old and thus a useful guide fossil for the Early Cambrian. Olenellus had a well-developed head, large and crescentic eyes, and a poorly developed, small tail. The fellow you see had a bit of his tail crushed as he turned to stone.

This specimen of Olenellus is from the Lower Cambrian Eager Formation of British Columbia and is typical of the group. He's from the Rifle Range outcrop near Cranbrook. 

The site — which is literally on a Rifle Range where folks go to shoot at things — is just a shade older than the Burgess Shale. Burgess is Middle Cambrian and the deposits there have similar species to the ones found here are the Eager fauna is much less varied. Trilobites were amongst the earliest fossils with hard skeletons. While they are extinct today, they were the dominant life form at the beginning of the Cambrian and it is what we find as the primary fossil fauna in the Eager Formation. The Eager Formation has produced many beautifully preserved Wanneria, abundant Olellenus and a handful of rare and treasured Tuzoia. The shale matrix lends itself to amazing preservation. The specimens of Wanneria from here are large. Some are up to thirteen centimetres long and ten centimetres wide. You find a mixture of complete specimens and head impressions from years of perfectly preserved moults.

Thursday, 11 June 2020

PORTUNOID CRAB

Ventral view of the carnivorous portunoid crab Ophthalmoplax brasiliana (Maury, 1930) from the latest Maastrichtian (~66.2 Ma.) deposits near Coahuila, northern Mexico.

This marine species was originally thought to have been found only in the upper Member, Owl Creek Formation,  Late/Upper Maastrichtian deposits of Tippah County in Mississippi, USA. 

Sohl and Koch published on the Mississippian find in the USGS in 1983. Francisco J. Vega and Torry Nyborg, along with George Phillips and Jose F. Ventura published on the Morphology and size variation of a portunoid crab from the Maastrichtian of the Americas in the Journal of South American Earth Sciences in November 2013. Fedorov and Nyborg published on this same species again in 2017. Paleocoordinates: (34.8° N, 88.9° W: 38.3° N, 66.2° W)

Vega, Francisco & Phillips, George & Nyborg, Torrey & Ventura, José F. & Clements, Don & Espinosa, Belinda & Solís-Pichardo, Gabriela. (2013). Morphology and size variation of a portunoid crab from the Maastrichtian of the Americas. Journal of South American Earth Sciences. 47. 116–135. 10.1016/j.jsames.2013.07.005. Photo: Ophthalmoplax brasiliana by the deeply awesome José F. Ventura‎

Tuesday, 9 June 2020

THE ELEPHANT BIRDS OF MADAGASCAR

Aepyornis skeleton, Monnier, 1913
One hundred and seventy million years ago, Madagascar was landlocked in the middle of the supercontinent Gondwana, sandwiched between land that would eventually become South America and Africa and land that would eventually become India, Australia, and Antarctica.

Riding the movements of the Earth's crust, Madagascar, along with India, first split from Africa and South America and then from Australia and Antarctica, and started heading north. India eventually smashed into Asia — forming the Himalayas in the process — but Madagascar broke away from India and was marooned in the Indian Ocean. Madagascar has been on its own for the past 88 million years.

Elephant birds are members of the extinct ratite family Aepyornithidae, made up of large to enormous flightless birds that once lived on the island of Madagascar. A ratite is any of a diverse group of flightless and mostly large and long-legged birds of the infraclass Palaeognathae.

Elephant birds became extinct, around 1000–1200 CE, as a result of human hunting. Elephant birds comprised the genera Mullerornis, Vorombe and Aepyornis. While they were in close geographical proximity to the ostrich, their closest living relatives are the much smaller nocturnal Kiwi — found only in New Zealand — suggesting that ratites did not diversify by vicariance during the breakup of Gondwana but instead evolved from ancestors that dispersed more recently by flying.

Elephant birds were endemic to Madagascar. Phylogenetic, genetic, and fossil evidence all suggest that the elephant bird, along with the ostrich, arrived in Madagascar and India when these landmasses were still connected to Australia and Antarctica via a land bridge.

When India and Madagascar split, the elephant bird wound up surviving on Madagascar, while the ostrich was carried north with India and was eventually introduced to Eurasia when India collided with the continent. The presence of the elephant bird on Madagascar can be chalked up to vicariance; it was living on Madagascar land already when Madagascar broke off from India. Most of the species on Madagascar today seem to be descended from individuals that dispersed from Africa long after Madagascar was established as a separate island.

Photo: Aepyornis skeleton. Quaternary of Madagascar by Monnier, 1913 by Monnier - http://digimorph.org/specimens/Aepyornis_maximus/Aepyornis.phtml digimorph.org, Public Domain, https://commons.wikimedia.org/w/index.php?curid=79655

Image: Size of Aepyornis maximus (centre, in purple) compared to a human, an ostrich (second from right, in maroon), and some non-avian theropod dinosaurs. Grid spacings are 1.0 m by Matt Martyniuk.

Cooper, A., Lalueza-Fox, C., Anderson, S., Rambaut, A., Austin, J., and Ward, R. (2001). Complete mitochondrial genome sequences of two extinct moas clarify ratite evolution. Nature 409:704-707.

Goodman, S. M., and Benstead, J. P. (2005). Updated estimates of biotic diversity and endemism for Madagascar. Oryx 39(1):73-77.

Evolution Berkeley: https://evolution.berkeley.edu/evolibrary/news/091001_madagascar

Vences, M., Wollenberg, K. C., Vieites, D. R., and Lees, D. C. (2009). Madagascar as a model region of species diversification. Trends in Ecology and Evolution 24(8):456-465.

Monday, 8 June 2020

URSUS CURIOUS: TLA'YI

A young Black Bear cub, Ursus americanus, checks out a frisky, startled Striped Skunk, Mephitis mephitis, both native species in southern British Columbia. 

While related to polecats and other members of the weasel family, skunks have as their closest Old World relatives the stink badgers.

The animals are known for their ability to spray a liquid with a strong, unpleasant smell. Generally, the aroma from a skunk is enough of a deterrent to keep curiosity at bay. Not in this case.

Bear cubs are known for being playful and altogether too curious. Born in January, they usually stick pretty close to Mamma for the first two years of their lives but sometimes an intriguing opportunity for discovery will cross their path and entice them to slip away just for a few minutes to check it out. Yearlings are usually quite skittish, spending their time hidden up in trees. By the end of the summer, they grow into confident little bears. The karma gods were good to this wee one. Nobody was skunked in this quest for exploration, though not for lack of trying.

We are blessed to have them living amongst us today on the rugged west coast of British Columbia. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, this little cutie is t̕ła'yi — a lovely, playful black bear.

Sunday, 7 June 2020

ELEPHANT SHREW

This adorable little fellow is a Short-eared elephant shrew, Macroscelides proboscideus, one of 15 species of this order. They range in size from 9.5-12.5 cm.

These small, quadrupedal, insectivorous mammals strongly resemble rodents or opossums with their scaly tails, elongated snouts, and rather longish legs.

They live in the desert and temperate grasslands of southern Africa. The Elephant shrew is considered "Living Fossils" as their distinctive morphology has not changed all that much in the past 30 million years. They ought to have been named Elephant Bunny shrew. They move through the world like wee baby elephant-bunnies, snuffling on all fours and hopping about looking for tasty snacks. They have a preference for seeds, fruit, termites and berries. They know how to live well, taking a siesta each afternoon when the sun gets high in the sky.

Thursday, 4 June 2020

BASILEMYS FORELIMB

A beautifully articulated Basilemys turtle forelimb with osteoderms on the palmar surface. This specimen is from outcrops in the Kaiparowits Formation of Utah, USA.

Basilemys is an extinct genus of early terrestrial or land turtles belonging to the family Nanhsiungchelyideae. They had a carapace similar in shape to aquatic turtles but limps and beak closer to terrestrial herbivores.

Today, these lovelies live in the Hell Creek floodplains munching on bits of grass and swamp plants. They are ectotherms, cold-blooded, reptiles and amniotes — they breathed air and did not lay eggs underwater but came to shore similar to modern turtles. They are known from Cretaceous deposits in North America and Asia. We've got some lovely examples from the Horseshoe Canyon Formation in Alberta and the Sustut Basin in northern British Columbia. Fossil remains of Basilemys have also been found in Saskatchewan, China, Kazakhstan, Mexico, Mongolia, the United States in California, Colorado, Montana, New Mexico, North Dakota, South Dakota, Texas, Utah, Wyoming and Uzbekistan from 144 collections and 152 occurrences. Photo credit: Joe Sertich