Friday 21 April 2023
UPPER TRIASSIC LUNING FORMATION
Thursday 20 April 2023
FOSSIL SALMON OF PUGET SOUND
The fossil specimens include individuals with enlarged breeding teeth and worn caudal fins. It is likely that these salmon acted very similar to their modern counterparts with males partaking in competitive and sneaky tactics to gain access to the sexiest (large and red) females who were ready to mate. These ancient salmon had migrated, dug their nests, spawned and defended their eggs prior to their death. For now, we're referring to the species found here as Oncorhynchus nerka, as they have many of the characteristics of sockeye salmon, but also several minor traits of the Pink Salmon, Oncorhynchus gorbuscha.
Oncorhynchus nerka, Pleistocene Sockeye Salmon |
It looks as though this population diverged from the original species about one million years ago, possibly when the salmon were deposited at the head of a proglacial lake impounded by the Salmon Springs advancement of a great glacier known as the Puget lobe of the Cordilleran Ice Sheet.
After the ice began melting and retreating north, the landscape slowly changed — both the land and sea levels rising — and great freshwater lakes forming in the lowlands filled with glacial waters from the melting ice. The sea levels rose quite considerably, about one and a half centimetres per year between 18,000 and 13,000 years ago. The isostatic rebound (rising) of the land rose even higher with an elevation gain of about ten centimetres per year from 16,000 to 12,500 years ago.
Around 14,900 years ago, sea levels had risen to a point where the salty waters of Puget Sound began to slowly fill the lowlands. Both the land and sea continued to rise and by 5,000 years ago, the sea level was about just over 3 meters lower than it is today. The years following were an interesting time in the geologic history of the Pacific Northwest. The geology of the South Fork Skokomish River continued to shift, undergoing a complicated series of glacial damming and river diversions after these salmon remains were deposited.
Today, we find their remains near the head of a former glacial lake at an elevation of 115 metres on land owned by the Green Diamond Company. The first fossil specimens were found back in 2001 by locals fishing for trout along the South Fork Skokomish River.
Upon seeing the fossil specimens, Smith teamed up with David Montgomery of the University of Washington, Seattle, along with N. Phil Peterson and Bruce Crowley, a Late Oligocene Mysticete specialist from the Burke Museum, to complete fieldwork and author a paper.
The fossil specimen you see here is housed in the Burke Museum collection. They opened the doors to their new building and exhibitions in the Fall of 2019. These photos are by the deeply awesome John Fam from a trip to see the newly opened exhibits this year. If you fancy a visit to the Burke Museum, check out their website here: https://www.burkemuseum.org/.
David B. Williams did up a nice piece on historylink.org on the Salmon of the Puget lowland. You can find his work here: https://www.historylink.org/File/20263
If you'd like to read more of the papers on the topic, check out:
- Smith, G., Montgomery, D., Peterson, N., and Crowley, B. (2007). Spawning sockeye salmon fossils in Pleistocene lake beds of Skokomish Valley, Washington. Quaternary Research, 68(2), 227-238. doi:10.1016/j.yqres.2007.03.007.
- Easterbrook, D.J., Briggs, N.D., Westgate, J.A., and Gorton, M.P. (1981). Age of the Salmon Springs Glaciation in Washington. Geology 9, 87–93.
- Hikita, T. (1962). Ecological and morphological studies of the genus Oncorhynchus (Salmonidae) with particular consideration on phylogeny. Scientific Reports of the Hokkaido Salmon Hatchery 17, 1–97.
If you fancy a read of Crowley's work on Late Oligocene Mysticete from Washington State, you can check out: Crowley, B., & Barnes, L. (1996). A New Late Oligocene Mysticete from Washington State. The Paleontological Society Special Publications, 8, 90-90. doi:10.1017/S2475262200000927
Wednesday 19 April 2023
CLALLAM BAY MARINE FAUNA
Panopea abrupt (Conrad, 1894) |
This fossil specimen was collected from lower Miocene deposits in the Clallam Formation on the foreshore bordering the Strait of Juan de Fuca near Clallam Bay, Olympic Peninsula, northwestern Washington. The oldest recorded specimen of one of their modern relatives lived not too far from here in the Strait of Juan de Fuca. That lovely was an impressive 168 years old.
A geoduck sucks water containing plankton down through its long siphon, filters this for food and ejects its refuse out through a separate hole in the siphon. Adult geoducks have few natural predators, which may also contribute to their longevity.
In Alaska, sea otters and dogfish have proved capable of dislodging geoducks; starfish also attack and feed on the exposed geoduck siphon.
Clallam Bay is a sleepy little town on the northwestern edge of the Olympic Peninsula. It was founded back in the 1880s as a steamboat stop and later served as a Mill town. If you are planning to visit the fossil exposures, head to the edge of town where it meets the sea.
Once at the water's edge, head east along the shore until you can go no further. You'll find marine fossils in the sandstone on the shore and cliffs. Mind the tide as access to the fossil site is only possible at low or mid-tide. You'll have to swim for it if you time it poorly. Clallam Bay: 48°15′17″N 124°15′30″W.
Near this site, there are many additional fossil localities to explore. In Sequim Bay, you can find Pleistocene vertebrates as well as Miocene cetacean bones near Slip Point. Near the Twin Post Office, you can find Oligocene nautiloids and bivalves (2.5km west in the bluff); You can find crabs including, Branchioplax in the Eocene limestone concretions from Neah Bay.
References: Addicott, Warren. Molluscan paleontology of the lower Miocene Clallam Formation, northwestern Washington, Geological Survey Paper 976.
Tuesday 18 April 2023
AMMONITES OF THE CAUCAUS MOUNTAINS
Geologically, the Caucasus Mountains belong to a system that extends from southeastern Europe into Asia and is considered a border between them. The Greater Caucasus Mountains are mainly composed of Cretaceous and Jurassic rocks with the Paleozoic and Precambrian rocks in the higher regions.
Some volcanic formations are found throughout the range. On the other hand, the Lesser Caucasus Mountains are formed predominantly of the Paleogene rocks with a much smaller portion of the Jurassic and Cretaceous rocks.
The evolution of the Caucasus began from the Late Triassic to the Late Jurassic during the Cimmerian orogeny at the active margin of the Tethys Ocean while the uplift of the Greater Caucasus is dated to the Miocene during the Alpine orogeny.
The Caucasus Mountains formed largely as the result of a tectonic plate collision between the Arabian plate moving northwards with respect to the Eurasian plate. As the Tethys Sea was closed and the Arabian Plate collided with the Iranian Plate and was pushed against it and with the clockwise movement of the Eurasian Plate towards the Iranian Plate and their final collision, the Iranian Plate was pressed against the Eurasian Plate.
As this happened, the entire rocks that had been deposited in this basin from the Jurassic to the Miocene were folded to form the Greater Caucasus Mountains. This collision also caused the uplift and the Cenozoic volcanic activity in the Lesser Caucasus Mountains.
The preservation of this Russian specimen is outstanding. Acanthohoplites bigoureti are also found in Madagascar, Mozambique, in the Rhone-Alps of France and the Western High Atlas Mountains and near Marrakech in Morocco. This specimen measures 55mm and is in the collection of the deeply awesome Emil Black.
Monday 17 April 2023
TRIASSIC OF NORTH AMERICA
Tozer's interest in our marine invert friends was their distribution and what those occurrences could tell us. 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.
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, the faunas of the lower paleo latitudes can be found up to 3000 km north of their counterparts on the American plate. This indicates a tectonic shift of this 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 fauna provinces can be distinguished from one another. The differences in fauna are obviously linked to the paleolatitude. They are called LPL, MPL, HPL (lower, middle, higher paleolatitude). Nevada provides the diagnostic features of the lower; northeastern British Columbia that of the middle and Sverdrup Basin that of the higher paleolatitude. 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.
Diatoms / Microalgae dominant components of phytoplankton |
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. The terranes that now form the western Cordillera were probably welded together and reached the North American plate before the end of the Jurassic period.
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.
Sunday 16 April 2023
HYPHANTOCERAS ORIENTALE
This an adult specimen (not the juvenile stage) from Upper Santonian outcrops near Ashibetsu, Hokkaido, Japan.
Aiba published on a possible phylogenetic relationship of two species of Hyphantoceras (Ammonoidea, Nostoceratidae) earlier this year, proposing that a phylogenetic relationship may exist based on newly found specimens with precise stratigraphic occurrences in the Kotanbetsu and Obira areas, northwestern Hokkaido.
Two closely related species, Hyphantoceras transitorium and H. orientale, were recognized in the examined specimens from the Kotanbetsu and Obira areas. Specimens of H. transitorium show wide intraspecific variation in the whorl shape. The stratigraphic occurrences of the two species indicate that they occur successively in the Santonian–lowermost Campanian, without stratigraphic overlapping.
Aiba, Daisuke. (2019). A Possible Phylogenetic Relationship of Two Species of Hyphantoceras (Ammonoidea, Nostoceratidae) in the Cretaceous Yezo Group, Northern Japan. Paleontological Research. 23. 65-80. 10.2517/2018PR010.
Saturday 15 April 2023
SOFT-BODIED PRESERVATION: THE MIGUASHA COLLECTION
If you look closely at this specimen, you can see the remarkable 3-D and soft-bodied preservation. This fish specimen reminds me of the ray-finned fossil fish you see in carbonate concretion from Lower Cretaceous deposits in the Santana Formation, Brazil.
Eusthenopteron would have shared our ancient seas with the first ammonites and primitive sharks, along with well-established fauna including the trilobites, brachiopods, coral reefs and a whole host of interesting arthropods.
Miguasha National Park / Parc National de Miguasha, is a protected area near Carleton-sur-Mer on the Gaspé Peninsula along the south side of the Saint Lawrence River to the east of the Matapedia Valley in Quebec, Canada. It was created in 1985 by the Government of Quebec and designated as a World Heritage Site in 1999 in honour of paleontological significance for Devonian fish, flower and spore fossils.
These fossils represent five of the six main fossil fish groups recorded from the Devonian (370 million years ago) including specimens of the lobe-finned fish and tetrapods. We see the placoderms, armoured prehistoric fish, in their heyday, dominating almost every known aquatic environment. The Devonian is known as the 'Age of Fishes,' but it could have equally been called the 'Age of Spores,' as this was a time of significant adaptive radiation of terrestrial biota and free-sporing vascular plants. Immense forests carpeted the continents and we see the first of the plant groups evolving leaves, true roots and seeds.
The site was discovered in 1842 by a local geologist and medical doctor, Abraham Gesner. He shared much of his collection with both the British Museum and Royal Scottish Museum for further study. Other names for this site are the Miguasha Fossil Site, the Bay of Escuminac Fossil Site, the Upper Devonian Escuminac Formation, and the Hugh-Miller Cliffs. It is also sometimes referred to on fossil specimens as 'Scaumenac Bay' or 'Scaumenac Bay P.Q. Photo credit to the deeply awesome John Fam
Friday 14 April 2023
OSTRACODERMS TO ANGLERFISH
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.
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 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 |
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.
Thursday 13 April 2023
ANCIENT SEAS: HOKKAIDO
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
Wednesday 12 April 2023
ANCIENT OCTOPUS: KEUPPIA
This cutie is in the family Palaeoctopodidae, and one of the earliest representatives of the order Octopoda — and perhaps my favourite fossil. It was this perfect specimen that inspired the logo for the Fossil Huntress brand.
These ancient marine beauties are in the class Cephalopoda making them relatives of our modern octopus, squid and cuttlefish.
There are two species of Keuppia, Keuppia hyperbolaris and Keuppia levante, both of which we find as fossils. We find their remains, along with those of the genus Styletoctopus, in Cretaceous-age Hâqel and Hjoula localities in Lebanon.
For many years, Palaeoctopus newboldi (Woodward, 1896) from the Santonian limestones at Sâhel Aalma, Lebanon, was the only known pre‐Cenozoic coleoid cephalopod believed to have an unambiguous stem‐lineage representative of Octobrachia fioroni.
With the unearthing of some extraordinary specimens with exquisite soft‐part preservation in the Lebanon limestones, our understanding of ancient octopus morphology has blossomed. The specimens are from the sub‐lithographical limestones of Hâqel and Hâdjoula, in northwestern Lebanon. These localities are about 15 km apart, 45 km away from Beirut and 15 km away from the coastal city of Jbail. Fuchs et al. put a nice little map in their 2009 paper that I've included and referenced here.
Palaeoctopus newboldi had a spherical mantle sac, a head‐mantle fusion, eight equal arms armed with suckers, an ink sac, a medially isolated shell vestige, and a pair of (sub‐) terminal fins. The bipartite shell vestige suggests that Palaeoctopus belongs to the octopod stem‐lineage, as the sister taxon of the Octopoda, the Cirroctopoda, is characterized by an unpaired clasp‐like shell vestige (Engeser 1988; Haas 2002; Bizikov 2004).
It is from the comparisons of Canadian fauna combined with those from Lebanon and Japan that things really started to get interesting with Octobrachia. Working with fossil specimens from the Campanian of Canada, Fuchs et al. (2007a ) published on the first record of an unpaired, saddle‐shaped shell vestige that might have belonged to a cirroctopod.Again from the Santonian–Campanian of Canada and Japan, Tanabe et al. (2008) reported on at least four different jaw morphotypes. Two of them — Paleocirroteuthis haggarti (Tanabe et al., 2008) and Paleocirroteuthis Pacifica (Tanabe et al ., 2008) — have been interpreted as being of cirroctopod type, one of octopod type, and one of uncertain octobrachiate type.
Interestingly Fuchs et al. have gone on to describe the second species of Palaeoctopus, the Turonian Palaeoctopus pelagicus from limestones at Vallecillo, Mexico. While more of this fauna will likely be recovered in time, their work is based solely on a medially isolated shell vestige.
Five new specimens have been found in the well-known Upper Cenomanian limestones at Hâqel and Hâdjoula in Lebanon that can be reliably placed within the Octopoda. Fuchs et al. described these exceptionally well‐preserved specimens and discuss their morphology in the context of phylogeny and evolution in their 2008 paper (2009 publishing) in the Palaeontology Association Journal, Volume 51, Issue 1.
The presence of a gladius vestige in this genus shows a transition from squid to octopus in which the inner shell has divided into two parts in early forms to eventually be reduced to lateralized stylets, as can be seen in Styletoctopus.
The adorable fellow you see here with his remarkable soft-bodied preservation and inks sack and beak clearly visible is Keuppia levante. He hails from Late Cretaceous (Upper Cenomanian) limestone deposits near Hâdjoula, northwestern Lebanon. The vampyropod coleoid, Glyphiteuthis abisaadiorum n. sp. is also found at this locality. This specimen is about 5 cm long.
Fuchs, D.; Bracchi, G.; Weis, R. (2009). "New octopods (Cephalopoda: Coleoidea) from the Late Cretaceous (Upper Cenomanian) of Hâkel and Hâdjoula, Lebanon". Palaeontology. 52: 65–81. doi:10.1111/j.1475-4983.2008.00828.x.
Photo one: Fossil Huntress. Figure Two: Topographic map of north‐western Lebanon with the outcrop area in the upper right-hand corner. Fuchs et al, 2009.
Tuesday 11 April 2023
BRACHIOPODA: LOPHOTROCHOZOANS
Clams or bivalves are molluscs, the second-largest phylum of invertebrates with about 85,000 extant species. While brachiopods share some similarities with their molluscan friends they are in a phylum all their own.
Brachiopods are small marine shellfish that are not so common today but back in the Palaeozoic they were plentiful the world over. The two valves that make up a brachiopods shell are of different sizes and if you look closely you'll see that the hinge runs top and bottom -- versus left and right like a clam.
Brachiopods had evolved from an ancestor similar to Halkieria, a slug-like Cambrian animal with "chain mail" on its back and a shell at the front and rear end; it was thought that the ancestral brachiopod converted its shells into a pair of valves by folding the rear part of its body under its front.
New fossils found in the last few years have shown us that the "chain mail" of tommotiids formed the tube of a sessile animal; one tommotiid resembled phoronids, which are close relatives or a subgroup of brachiopods, while the other tommotiid bore two symmetrical plates that might be an early form of brachiopod valves. Lineages of brachiopods that have both fossil and extant taxa appeared in the early Cambrian, Ordovician, and Carboniferous periods, respectively.
Other lineages have arisen and then become extinct, sometimes during severe mass extinctions. At their peak in the Paleozoic era, the brachiopods were among the most abundant filter-feeders and reef-builders and occupied other ecological niches, including swimming in the jet-propulsion style of scallops. Brachiopod fossils have been useful indicators of climate changes during the Paleozoic. However, after the Permian–Triassic extinction event, brachiopods recovered only a third of their former diversity.
Brachiopods were especially vulnerable to the Permian–Triassic extinction, as they built calcareous hard parts — made of calcium carbonate — and had low metabolic rates and weak respiratory systems. It was often thought that brachiopods went into decline after the Permian–Triassic extinction, and were out-competed by bivalves, but both brachiopod and bivalve species increased from the Paleozoic to modern times, with bivalves increasing faster; after the Permian–Triassic extinction, brachiopods became for the first time less diverse than bivalves.
Their lineage dates back to the Cambrian with over 12,000 fossil species and 350 living relatives sorted between 6,000 genera. There are two major groups of brachiopods, articulate with toothed hinges and simple open and closing muscles to manipulate their shells and inarticulate brachiopods with untoothed hinges and a more complex set of muscles used to control the brachial supports used to open and close their shells.
Monday 10 April 2023
AMAZING AMMONITE: HOLCOPHYLLOCERAS
Madagascar is a treasure trove of outstanding fossil species and this Holcophylloceras ammonite is no exception.
The shells had many chambers divided by walls called septa. The chambers were connected by a tube called a siphuncle which allowed for the control of buoyancy with the hollow inner chambers of the shell acting as air tanks to help them float.
We can see the edges of this specimen's shell where it would have continued out to the last chamber, the body chamber, where the ammonite lived. Picture a squid or octopus, now add a shell and a ton of water.
Sunday 9 April 2023
LOWER LIAS LYTOCERAS
Lytoceras sp. Photo: Craig Chivers |
The concretion prior to prep |
Saturday 8 April 2023
PORT HARDY: TIME AND TIDE
Just outside Port Hardy further south on the west coast is the area known as Fort Rupert or Tsaxis.
It was here that the Hudson's Bay Company built Fort Rupert both for trade with the local First Nation population and the allure of potential coal deposits.
I headed up to the north island this past week to stomp around my old haunts, visit with family and get in a bit of late season kayaking. The town was much as I remembered it. There have been changes, of course. I lived up on Wally's hill above the reserve at Tsaxis beside the old cemetery.
My wee childhood home is still there and I am very pleased to see that the earthly home of my ancestors is well maintained. The cemetery is groomed and cared for but the land surrounding it is overgrown and it took me a few minutes to orient myself to see where things used to be. Where the old Hudson's Bay Company Fort and its iconic chimney were in relation to the graveyard.
A lifetimes worth of memories came flooding back. Those from my earliest years and then later when I returned to kayak, fish and scuba dive in these rich waters.My plans of blissful days kayaking and taking photos of the scenery were altered by hurricane-force winds. Still beautiful, but chilly and choppy.
The beachhead here was clocking 120 km winds so I did a brief visit to the homestead, the graveyard and Jokerville then headed home to light the fire and hunker in as the storm blew through.
Port Harty and Fort Rupert have an interesting history and how you read it or hear it truly depends on the lens that is applied. This has been the ancestral home to many First Nation groups. Mostly they were passing through and coming here to dig up delicious butter clams, roots, berries and other natural yummy goodness. Years before Port Hardy was settled at the turn of the century it was the home to the Kwakiutl or Kwagu’ł and part of my heritage.
Alec and Sarah Lyon operated a store and post office on the east side of Hardy Bay. A 1912 land deal promoted by the Hardy Bay Land Co., put the area on the map and increased its population. By 1914, 12 families had settled, built a school, sawmill, church and hotel.
The community of Port Hardy is situated within traditional Kwagu’ł First Nation territory. It is also home to the Gwa’sala-‘Nakwaxda’xw First Nation. In 1964 all the First Nations communities were amalgamated and forced to relocate from their traditional territories by the federal government, for administrative reasons.
The First Nation families were told that it would cost less for education, easier for medical help, and the government would help with housing, but it turned out to be a hidden agenda designed to assimilate the various groups into Canadian society — or face extermination. Several years of threats and promises later, the Gwa’sala and ‘Nakwaxda’xw reluctantly gave in to the relocation, but the government didn’t keep their promise for adequate housing.
There were five homes for over 200 people on the Tsulquate Reservation. The Gwa’sala traditional territory is Smith Inlet and surrounding islands. ‘Nakwaxda’xw traditional territory is Seymour Inlet, the Deserter’s Group, Blunden Harbour, and surrounding islands.
There was limited access to the community until the logging road connecting Port Hardy to Campbell River was paved in December of 1979.
Port Hardy’s population grew to a little over 5,000 residents during the Island Copper Mine years (1971-1995). The former mine site is located 16 kilometres south of Port Hardy on the shores of Rupert Inlet. The open-pit porphyry copper mine employed over 900 employees from Port Hardy and the surrounding communities. Today, the former mine has been transformed into a wildlife habitat and pit lake biological treatment system (BHP Copper Inc., 2010). The Quatsino First Nation manage the property and their Economic Development Board is exploring options for its use.
The Quatsino First Nations have conducted several feasibility studies around the implementation of a puck or brickett mill onsite, utilizing the existing infrastructure, which includes six industrial buildings.
Today, Port Hardy serves as the crossroads for air, ferry and marine transportation networks, and serves as the gateway to the fast-growing Central Coast, the Cape Scott and North Coast Trails, and BC Ferry’s northern terminus for the Discovery Coast run and Prince Rupert. It supports several traditional and emerging sectors and remains rich in natural resources and community spirit.
Every corner of the Port Hardy region is enriched with culture and history. Starting with the two welcome poles in Carrot Park, both carved and replicated by Calvin Hunt, a Kwagu’ł artist who is based in Tsax̱is.
From here and along the seawall are interpretive signs with Kwak’wala words for various wildlife, such as salmon, bear, wolf, and orca. At the end of this walk is Tsulquate Park.
From here you can see across Queen Charlotte Strait; the ocean highway and lands of the Kwakwa̱ka̱ʼwakw. Port Hardy was named after Vice-Admiral Sir Thomas Masterman Hardy (5 April 1769 – 20 September 1839) who served as the captain of H.M.S. Victory in the Royal Navy.
He served at the Battle of Trafalgar and held Lord Nelson at the end of that battle where Nelson died in his arms. Though he never visited this island community, it bears his name today.
A ten-minute drive from downtown Port Hardy, in the neighbouring community of Fort Rupert, is the village of Tsax̱is. This is the current home of the Kwagu’ł First Nation. Here lies elaborated totem poles and the big house; a venue where First Nations ceremonies take place, such as the potlatch.The potlatch is a First Nations constitution that determines our politics, our government, our education, our medicine, our territory, and our jurisdiction. Potlatch is a complex event with several ceremonies, which are still practiced in buildings like the Tsax̱is big house.
On the front porch of the village of Tsax̱is is Tayaguł (Storey’s Beach). Along this waterfront were several villages, which are depicted on map (pictured below) by Mervyn Child, a Kwagu’ł artist.
Across the way and middle of K’ak’a (Beaver Harbour) are Atłanudzi (Cattle Island), Ḵ’ut’sa̱dze (Peel Island), Ḵ’a̱msa̱x̱tłe (Shell Island), and Uxwiwe’ (Deer Island). Once the words are broken down and translated; the names of these islands are unique to their environment, as they’re part of a story that belongs to the Kwagu’ł.
Where: Port Hardy, British Columbia. 50°43'27"N, 127°29'52"W
Friday 7 April 2023
DACTYLIOCERAS AMMONITE PREPPED BY HARRY TABINER
Dactylioceras ammonite, Photo: Harry Tabiner |
Holderness is an area of the East Riding of Yorkshire, on the east coast of England. An area of rich agricultural land, Holderness was marshland until it was drained in the Middle Ages. Topographically, Holderness has more in common with the Netherlands than with other parts of Yorkshire. To the north and west are the Yorkshire Wolds.
Geologically, Holderness is underlain by Cretaceous chalk but in most places, it is so deeply buried beneath glacial deposits that it has no influence on the landscape.
The landscape is dominated by deposits of till, boulder clays and glacial lake clays. These were deposited during the Devensian glaciation. The glacial deposits form a more or less continuous lowland plain which has some peat filled depressions (known locally as meres) which mark the presence of former lake beds. There are other glacial landscape features such as drumlin mounds, ridges and kettle holes scattered throughout the area.
Dactylioceras ammonite, Photo: Harry Tabiner |
The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic.
The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the southeast are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages.
The strata become gradually younger from west to east. Much of Yorkshire presents heavily glaciated scenery as few places escaped the direct or indirect impact of the great ice sheets as they first advanced and then retreated during the last ice age. This beauty is in the collection of the deeply awesome Harry Tabiner.
Thursday 6 April 2023
HARRISON LAKE: FOSSILS AND THE BEATING HEART
But there are some who come to Harrison Lake and miss the town entirely. Instead, they favour the upper west side of the lake and the fossiliferous bounty found here.
Indeed, this is the perfect location for local citizen scientists to strut their stuff. Harrison is a perfect family day trip, where you can discover wonderful marine fossil specimens as complete or partially crushed fossilized shells embedded in rock.
It is truly amazing that we can find them at all. These beauties range in age from Jurassic to Cretaceous, with most being Lower Callovian, meaning the ammonites here swam our ancient oceans more than 160 million years ago.
The area around Harrison Lake has been home to the Sts’ailes, a sovereign Coast Salish First Nation for thousands of years. Sts’ailes’ means, “the beating heart,” and it sums up this glorious wilderness perfectly. They describe their ancient home as Xa’xa Temexw or Sacred Earth.
With the settling of Canada, Geologists began exploring the area in the 1880s, calling upon the Sts’ailes to help them look for coal and a route for the Canadian Pacific Railway. Coal was the aim, but happily, they also found fossils. Sacred Earth, indeed.
Belemnite Fossils |
Further up the road, you will see Cretaceous cigar-shaped squid-like cephalopods called Belemnites, and the bivalve (clam) Buchia — gifts deposited by glaciers. Here are the most common.
Ammonites
Almost all of the ammonite specimens found near Harrison Lake are the toonie sized Cadoceras (Paracadoceras) tonniense with well-preserved outer whorls but flattened inner whorls. We find semi-squished elliptical specimens here, too. If you see a large, smooth, inflated grapefruit-sized ammonite, you are holding a rare prize — a Cadoceras comma ammonite, the macroconch or female of the species.
Ammonites were predatory, squid-like creatures that lived inside coil-shaped shells. Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. They used these tentacles to snare prey — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunts today.
Within their shells, ammonites had a number of chambers called septa filled with gas or fluid, and they were interconnected through a wee air tube. By pushing air in or out, they were able to control their buoyancy.
These small but mighty marine predators lived in the last chamber of their shell and continuously built new shell material as they grew. As they added each new chamber, they would move their squid-like body down to occupy the final outside chamber.
Interestingly, ammonites from Harrison Lake are quite similar to the ones found within the lower part of the Chinitna Formation near Cook Inlet, Alaska, and Jurassic Point, Kyuquot, on the west coast of Vancouver Island — some of the most beautiful places on Earth.
Buchia (bivalve) Clams
The bivalve or clam Buchia are commonly found at Harrison Lake. You will see them cemented together en masse. . They populated Upper Jurassic–Lower Cretaceous waters like a team sport. When they thrived, they really thrived, building up large coquinas of material. Large boulders of Buchia cemented together en masse hitched a ride with the glaciers and were deposited around Harrison Lake. Some kept going and we find similar erratics or glacier-deposited boulders as far south as Washington state.
Buchia is used as Index Fossils. Index fossils help us to figure out the age of the rock we are looking at because they are abundant, populate an area en masse, and then die out quickly. In other words, they make it easy to identify a geologic time span.
So what does this mean to you? Now, when you are out and about with friends and discover rocks with Buchia, or made entirely of Buchia, you can say, “Oh, this looks to be Upper Jurassic or Lower Cretaceous. Come take a look! We're likely the first to lay eyes on this little clam since dinosaurs roamed the Earth.”
Fossil Collecting at Harrison Lake Fossil Field Trip — Getting there
This Harrison Lake site is a great day trip from Vancouver or the Fraser Valley. You will need a vehicle with good tires for travel on gravel roads. Search out the route ahead of time and share your trip plan with someone you trust. If you can pre-load the Google Earth map of the area, you will thank yourself.
Heading east on from Vancouver, it will take you 1.5-2 hours to reach Harrison Mills.
Access Forestry Road #17 at the northeast end of the parking lot from the Sasquatch Inn at 46001 Lougheed Hwy, Harrison Mills. From there, it will take about an hour to get to the site. Look for signs for the Chehalis River Fish Hatchery to get you started.
Drive 30 km up Forestry Road #1, and stop just past Hale Creek at 49.5° N, 121.9° W (paleo-coordinates 42.5° N, 63.4° W) on the west side of Harrison Lake. You will see Long Island to your right.
The first of the yummy fossil exposures are just north of Hale Creek on the west side of the road. Keep in mind that this is an active logging road, so watch your kids and pets carefully. Everyone should be wearing something bright so they can be easily spotted.
How to Spot the Fossils
The fossils here are easily collected—look in the bedrock and in the loose material that gathers in the ditches. Specimens will show up as either dark grey, grey-brown or black. Look for the large, dark-grey boulders the size of smart cars packed with Buchia.
And while you are at it, be on the lookout for anything that looks like bone. This site is also ripe for marine reptiles—think plesiosaur, mosasaur and elasmosaur. As a citizen scientist and budding palaeontologist, you might just find something new!
What to Know Before You Go
Fill your gas tank and pack a tasty lunch. As with all trips into British Columbia's wild places, dress for the weather. You will need hiking boots, rain gear, gloves, eye protection, and a good geologic hammer and rock (cold) chisel.
Wear bright clothing and keep your head covered. Slides are common, and you may start a few if you hike the cliffs. If you are with a group, those collecting below may want to consider hardhats in case of rockfall — chunks of rock the size of your fist up to the size of a grapefruit. They pack a punch.
Bring a colourful towel or something to put your keepers on. Once you set rock down, it can be hard to find again given the terrain. I take the extra precaution of spraying the ends of my hammers and chisels with yellow fluorescent paint, as I have lost too many in the field. You will also want to bring a camera for the blocks of Buchia that are too big to carry home.
Identifying Your Treasures
When you have finished for the day, compare your treasures to see which ones you would like to keep. In British Columbia, you are a steward of the fossil, which means they belong to the province, but you can keep them safe. You are not allowed to sell or ship them outside British Columbia without a permit.
Once you get home, wash and identify your finds. Harrison Lake does not have a large variety of fossil fauna, so this should not be difficult. If your find is coiled and round, it is an ammonite. If it is long and straight, it is a belemnite. And if it looks like a wee fat baby oyster, it is Buchia. This is not always true, but mostly true.
What about collecting fossils in all seasons?. Everyone has a preference. I prefer not to collect in the snow, but I have done it. While sunny days are lovely, it can also be easier to see the specimens when the rock is wet. So, do we do this in the rain? Heck, yeah!
In torrential rain?
Yes — once you are hooked, but for your casual friends or the kiddos, the answer is likely no. Choose your battles. They may come with you, but a cold day getting soaked is no fun.
In time, you will find your inner fossil geek — probably with your first find. And that's just the tip of the iceberg. First, it will be you, then your kids, your friends and then your neighbour. Once you start, it is easy to get hooked. Fossil addiction is real, and the only cure is to get out there and do it some more. You've got this!
References and further information:
A. J. Arthur, P. L. Smith, J. W. H. Monger and H. W. Tipper. 1993. Mesozoic stratigraphy and Jurassic palaeontology west of Harrison Lake, southwestern British Columbia. Geological Survey of Canada Bulletin 441:1-62
R. W. Imlay. 1953. Callovian (Jurassic) ammonites from the United States and Alaska Part 2. The Alaska Peninsula and Cook Inlet regions. United States Geological Survey Professional Paper 249-B:41-108
An overview of the tectonic history of the southern Coast Mountains, British Columbia; Monger, J W H; in, Field trips to Harrison Lake and Vancouver Island, British Columbia; Haggart, J W (ed.); Smith, P L (ed.). Canadian Paleontology Conference, Field Trip Guidebook 16, 2011 p. 1-11 (ESS Cont.# 20110248).
Wednesday 5 April 2023
JELLYFISH: GAGISAMA
Sea jellies and jellyfish are the common names for the medusa-phase or adult phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria — more closely related to anemones and corals.
Jellyfish are not fish at all. Jellyfish evolved millions of years before true fish.
The oldest conulariid scyphozoans — picture an ice-cream cone with fourfold symmetry — appeared between 635 and 577 million years ago in the Neoproterozoic of the Lantian Formation a 150-meter-thick sequence of rocks deposited in southern China.
Others are found in the youngest Ediacaran rocks of the Tamengo Formation of Brazil, c. 505 mya, through to the Triassic. Cubozoans and hydrozoans appeared in the Cambrian of the Marjum Formation in Utah, USA, c. 540 mya. Like other soft-bodied organisms, ctenophores (comb jellies), sea jellies and jellyfish only produce fossils only under exceptional taphonomic conditions — think rare.
I have seen all sorts of their brethren growing up on the west coast of Canada. I have seen them in tide pools, washed up on the beach and swam amongst thousands of Moon Jellyfish while scuba diving in the Salish Sea. Their movement in the water is marvellous.
In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, jellyfish are known as ǥaǥisama.The watercolour ǥaǥisama you see here is a bit of fancy. While I chose blue, purple and pink for these lovelies, they also come in bright yellow, orange and relatively clear — and are often luminescent.
Jellyfish such as comb jellies produce bright flashes to startle a predator, others such as siphonophores can produce a chain of light or release thousands of glowing particles into the water as a mimic of small plankton to confuse the predator.
For most jellyfish bioluminescence is used for defence against predators — and about half of all jellyfish are bioluminescent. Some produce a glowing sticky slime that clings to predators making them vulnerable to other predators. Some jellyfish can release their tentacles as glowing decoys. So you see that there are many strategies for using bioluminescence by jellyfish.
All bioluminescence comes from energy released from a chemical reaction. This is very different from other sources of light, such as from the sun or a light bulb, where the energy comes from heat. In a luminescent reaction, two types of chemicals, called luciferin and luciferase, combine together. The luciferase acts as an enzyme, allowing the luciferin to release energy as it is oxidized. The colour of the light depends on the chemical structures of the chemicals.
There are more than a dozen known chemical luminescent systems, indicating that bioluminescence evolved independently in different groups of organisms. One type of luciferin is called coelenterazine, found in jellyfish, shrimp, and fish. Dinoflagellates and krill share another class of unique luciferins, while ostracods (firefleas) and some fish have a completely different luciferin. The occurrence of identical luciferins for different types of organisms suggests a dietary source for some groups. Organisms such as bacteria and fireflies have unique luminescent chemistries. In many other groups, the chemistry is still unknown
Some of the most amazing deep-sea jellyfish are the comb jellies, which can get as large as a basketball, and are in some cases so fragile that they are almost impossible to collect intact.
Also spectacular are the siphonophores, some of which can reach several meters in length. Siphonophores deploy many tentacles like a gill net casting for small fish.
Tuesday 4 April 2023
HETEROPTERA: SNEAKOPTERA
The Green River Formation is an Eocene geologic formation that records a 12 million year history of sedimentation in a group of intermountain lakes in three basins along the present-day Green River in Colorado, Wyoming, and Utah. It is one of the most important outcrops we have for insight into life in the Eocene. It gives a window into what our world looked like about 50 million years ago.
Monday 3 April 2023
ICE AGE PROBOSCIDEANS: WOOLLY MAMMOTHS
He's now housed in the Museo Nacional De Ciencias Naturales in Madrid, Spain in a display that shows thoughtful comparisons between the proboscideans. They have a wonderful display of mammoth teeth, the diagnostic flat enamel plates and the equally distinct pointy cusped molars of the mastodons.
He was a true elephant, unlike his less robust cousins, the mastodons. Mammoths were bigger — both in girth and height — weighing in at a max of 13 tonnes.
They are closely related to Asian elephants and were about the size of the African elephants you see roaming the grasslands of Africa today.
If you stood beside him and reached way up, you might be able to touch his tusks but likely not reach up to his mouth or even his eyes.
He would have had a shaggy coat of light or dark coloured hair with long outer hair strands covering a dense thick undercoat. His oil glands would have worked overtime to secrete oils, giving him natural — and I'm guessing stinky — waterproofing.
Some of the hair strands we have recovered are more than a meter in length. These behemoth proboscideans boasted long, curved tusks, little ears, short tails and grazed on leaves, shrubs and grasses that would have been work to get at as much of the northern hemisphere was covered in ice and snow during his reign. It is often the teeth of mammoths like those you see in the photo here that we see displayed.
Their molar teeth were large and have always struck me as looking like ink plates from a printing press. If they are allowed to dry out in collection, they fall apart into discreet plates that can be mistaken for mineralized or calcified rock and not the bits and pieces of mammoth molars that they indeed are. Their large surface area was perfect for grinding down the low nutrient, but for the most part, plentiful grasses that sustained them.
Woolly Mammoth Tusk, Wrangel Island |
Their size offered protection against other predators once the mammoth was full grown. Sadly for the juveniles, they offered tasty prey to big cats like Homotherium who roamed those ancient grasslands alongside them.
They roamed widely in the Pliocene to Holocene, roaming much of Africa, Europe, Asia and North America. We see them first some 150,000 years ago from remains in Russia then expanding out from Spain to Alaska. They enjoyed a very long lifespan of 60-80 — up to 20 years longer than a mastodon and longer than modern elephants. They enjoyed the prime position as the Apex predator of the megafauna, then declined — partially because of the environment and food resources and partially because of their co-existence with humans. In places where the fossil record shows a preference for hunting smaller prey, humans and megafauna do better together. We see this in places like the Indian Subcontinent where primates and rodents made the menu more often than the large megafauna who roamed there. We also see this in present-day Africa, where the last of the large and lovely megafauna show remarkable resilience in the face of human co-existence.
The woolly mammoths from the Ukrainian-Russian plains died out 15,000 years ago. This population was followed by woolly mammoths from St. Paul Island in Alaska who died out 5,600 years ago — and quite surprisingly, at least to me, the last mammoth died just 4,000 years ago in the frosty ice on the small island of Wrangel in the Arctic Ocean — their final days spent scratching out a dwindling existence of genetic mutations, howling winds, rain-darkened hills and subsistence on tough grasses grown in thin soil.
Further reading: Laura Arppe, Juha A. Karhu, Sergey Vartanyan, Dorothée G. Drucker, Heli Etu-Sihvola, Hervé Bocherens. Thriving or surviving? The isotopic record of the Wrangel Island woolly mammoth population. Quaternary Science Reviews, 2019; 222: 105884 DOI: 10.1016/j.quascirev.2019.105884
Sunday 2 April 2023
ALCIDS AUKS: PUFFLING AND DUTIFUL PARENTING
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 in the region. 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.
Saturday 1 April 2023
AMMONITE OF THE RHÔNE
Porpoceras (Buchman, 1911) is a genus of ammonite that lived during the early and middle Toarcian stage of the Early Jurassic. We see members of this genus from the uppermost part of Serpentinum Zone to Variabilis Subzone. These beauties are found in Europe, Asia, North America and South America.
Ammonites belonging to this genus have evolute shells, with compressed to depressed whorl section. Flanks were slightly convex and venter has been low. The whorl section is sub-rectangular.
The rib is pronounced and somewhat fibulate on the inner whorls — just wee nodes here — and tuberculate to spined on the ventrolateral shoulder. It differs from Peronoceras by not having a compressed whorl section and regular nodes or fibulation. Catacoeloceras is also similar, but it has regular ventrolateral tubercules and is missing the classic nodes or fibulation of his cousins.
This specimen hails from southern France near the Rhône, one of the major rivers of Europe. It has twice the average water level of the Loire and is fed by the Rhône Glacier in the Swiss Alps at the far eastern end of the Swiss canton of Valais then passes through Lake Geneva before running through southeastern France. This 10 cm specimen was prepared by the supremely talented José Juárez Ruiz