West Cork, Ireland |
Saturday, 6 February 2021
SEAWEED: MACROALGAE
Friday, 5 February 2021
GIANT'S CAUSEWAY
Thursday, 4 February 2021
URSUS ARCTOS CARNIVORA
Grizzly Bear / North American Brown Bear |
At age five, female (sows) grizzlies begin mating and bearing young, usually two cubs every other year. The cubs arrive over the winter and feast on their mother's milk all snuggled inside a wintery den.
The great ancestors of the North American brown bear are the Ursavus, a bear-dog the size of a raccoon who lived more than 20 million years ago. Taking a look at this beauty, it seems an implausible lineage.
Wednesday, 3 February 2021
CAUGHT AT THE SCENE: KOALA
A peaceful koala napping |
Tuesday, 2 February 2021
BROWN, BLACK, POLAR & PANDA
For them and for us, I think things worked out for the best that they enjoy the rugged wild country they call home.
Bears are carnivoran mammals of the family Ursidae. They range in height from one to three metres.
Bears are the world’s largest land carnivores — animals that eat meat — dining on meat as well as roots, seeds, berries, insects and fish. Bears have broad heads, large bodies, and short legs and tails. They have poor eyesight and an excellent sense of smell. They are classified as caniforms or doglike carnivorans, related to dogs and raccoons.
Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere — making a home in North America, South America, Europe, and Asia.
The relatives of our black and brown bears, a dog-bear, entered the fossil record about 20 million years ago. We've found polar bear bones that tell us more about when they split off in the lineage.
DNA from a 110,000–130,000-year-old polar-bear fossil has been successfully sequenced. The genome, from a jawbone found in Svalbard, Norway, in 2004, indicates when polar bears, Ursus maritimus, diverged from their nearest common relative, the brown bear — Ursus arctos.
Because polar bears live on ice and their remains are unlikely to be buried in sediment and preserved, polar-bear fossils are very rare. So the discovery of a jawbone and canine tooth — the entirety of the Svalbard find — is impressive.But far more important, is that when molecular biologist Charlotte Lindqvist, then at the University of Oslo's Natural History Museum and now at the University at Buffalo in New York, drilled into the jaw, she was able to collect intact mitochondrial DNA. Yes, a bit Jurassic Park-esque.
Mitochondria — organelles found in animal cells — have their own DNA and can replicate. And because there are many mitochondria per cell, mitochondrial DNA is easier to find in fossils than nuclear DNA.
Lindqvist wondered whether this mitochondrial DNA could illuminate the evolutionary history of how and when polar bears diverged from brown bears. To find out, she worked with Stephan Schuster, a molecular biologist at Pennsylvania State University in University Park, and a team of colleagues to sequence the genetic material she had collected and was successful.
It is the oldest mammalian mitochondrial genome yet sequenced — about twice the age of the oldest mammoth genome, which dates to around 65,000 years old. From Lindqvist's work, we learned that polar bears split off the lineage from brown bears about 150,000 years ago. They evolved rapidly in the Late Pleistocene, taking advantage of their hunting prowess to become the apex predators of the northern arctic region.
In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest — or Kwakwaka'wakw, speakers of Kwak'wala — a grizzly bear is known as na̱n and the ornamental grizzly bear headdress worn by the comic Dluwalakha grizzly bear dancers in the Grizzly Bear Dance, Gaga̱lalał, is known as na̱ng̱a̱mł. A black bear is known as t̕ła'yi — though I do not know the word for Polar Bear in Kwak'wala.
Monday, 1 February 2021
BACK IN THE USSR: KEPPLERITES
Sunday, 31 January 2021
THERIZINOSAURUS: DINOSAUR EGGS
Therizinosaurus was a colossal therizinosaur that could grow up to 9–10 m (30–33 ft) long and weigh possibly over 3 t (3,000 kg). Like other therizinosaurs, it would have been a bit of a slowpoke on the ground. These fellows had a rhamphotheca (horny beak) and a wide torso for food processing.
The forelimbs were particularly robust and had three fingers that bore unguals which, unlike other relatives, were very stiffened, elongated, and only had significant curvatures at the tips. After years of taxonomic debate, nevertheless, they are now placed in one of the major dinosaur clades, Theropoda, specifically as maniraptorans.
Saturday, 30 January 2021
NAUTILUS: NAUTILIDAE
They have a seemingly simple brain, not the large complex brains of octopus, cuttlefish and squid, and had long been assumed to lack intelligence.
They are able to learn simple tasks and have the ability to remember food triggers. There was an experiment done that shone a blue light each time they were fed and then flickered on later without food. The nautilus responded to the light without delay when food was given. They quickly learned that the light was not an indicator of food when the light was turned on without issuing a tasty snack.
The cephalopod nervous system is quite different from that of other animals, and recent experiments have shown not only memory but a changing response to the same event over time.
Nautiluses usually inhabit depths of several hundred metres. It has long been believed that nautiluses rise at night to feed, mate, and lay eggs, but it appears that, in at least some populations, the vertical movement patterns of these animals are far more complex. Nautiluses are found in only the Indo-Pacific, from 30° N to 30° S latitude and 90° E to 175° E longitude. They inhabit the deep slopes of coral reefs.
Nautilus pompilius may be the deepest ocean dwelling nautilus. They have been spotted at depths of 703 m (2,306 ft) — very close to the estimated implosion depth of 800 m (2,600 ft).
Only in New Caledonia, the Loyalty Islands, and Vanuatu can nautiluses be observed in very shallow water, at depths of as little as 5 m (15 ft). This is due to the cooler surface waters found in these southern hemisphere habitats as compared to the many equatorial habitats of other nautilus populations – these usually being restricted to depths greater than 100 m (300 ft). Nautiluses generally avoid water temperatures above 25 °C (75 °F).
Friday, 29 January 2021
DOUVILLEICERAS INAEQUINODUM
The genus Douvilleiceras range from Middle to Late Cretaceous and can be found in Asia, Africa, Europe and North and South America.
Thursday, 28 January 2021
EXPLORING WRANGELLIA
Douvelliceras spiniferum, Cretaceous Haida Formation |
They form Wrangellia, an exotic tectonostratigraphic terrane that includes Vancouver Island, parts western British Columbia and Alaska.
The Geological Survey of Canada sponsored many expeditions to these remote islands and has produced numerous reference papers on this magnificent terrain, exploring both the geology and palaeontology of the area.
The praise was well-earned and foreshadowed his significant contributions to come. Sixteen years later, he wrote up and published his observations on a strange Mount Stephen fossil that resembled a kind of headless shrimp with poorly preserved appendages. Because of the unusual pointed shape of the supposed ventral appendages and the position of the spines near the posterior of the animal, Whiteaves named it Anomalocaris canadensis. The genus name "Anomalocaris" means "unlike other shrimp" and the species name "canadensis" refers to the country of origin.
Whiteaves work on the palaeontology of Haida Gwaii provided excellent reference tools, particularly his work on the Cretaceous exposures and fauna that can be found there.
One of our fossil field trips was to the ruggedly beautiful Cretaceous exposures of Lina Island. We had planned this trip as part of our “trips of a lifetime.” Both John Fam and Dan Bowen can be congratulated for their efforts in researching the area and ably coordinating a warm welcome by the First Nations community and organizing fossil field trips to some of the most amazing fossil localities in the Pacific Northwest.
With great sandstone beach exposures, the fossil-rich (Albian to Cenomanian) Haida formation provided ample specimens, some directly in the bedding planes and many in concretion. Many of the concretions contained multiple specimens of typical Haida Formation fauna, providing a window into this Cretaceous landscape.
It is always interesting to see who was making a living and co-existing in our ancient oceans at the time these fossils were laid down. We found multiple beautifully preserved specimens of the spiny ammonite, Douvelleiceras spiniferum along with Brewericeras hulenense, Cleoniceras perezianum and many cycads in concretion.
Photo: Pictured above is Douvilleiceras spiniferum with his naturally occurring black, shiny appearance. Proudly part of my collection. He is 6 inches long and 5 inches deep, typical of the species. The genus Douvilleiceras range from Middle to Late Cretaceous and can be found in Asia, Africa, Europe and North and South America. We have beautiful examples in the early to mid-Albian from the archipelago of Haida Gwaii in British Columbia. Joseph F. Whiteaves was the first to recognize the genus from Haida Gwaii when he was looking over the early collections of James Richardson and George Dawson.
Wednesday, 27 January 2021
H. SAVENYEI: RENE'S BEE
Rene was a mountain goat in the field, stalking the hills in his signature red t-shirt. He was tremendously knowledgeable about the natural world and delighted in it. For many years, he was Chair of the White Rock and Surrey Naturalists, while I was Chair of the Vancouver Paleontological Society. Together, we would plan and often co-lead field trips to many of the wonderful fossil outcrops in British Columbia and Washington state.
In 2002, we were planning a very exciting round of field trips. I was offered a fully paid trip to India with Karen Lund to hike to the headwaters of the Ganges, a trip which I was to forgo in favour of a hike up to the outcrops of the Cathedral Escarpment and Burgess Shale and then to yummy Lower Jurassic and Lower Cretaceous, Albian, outcrops accessed only by boat in Haida Gwaii.
Rene and I had talked about "walking in the shoes" of Joseph Whiteaves, the GSC's chief palaeontologist in Ottawa. He published a paper in 1876 describing the Jurassic and Cretaceous faunas of Skidegate Inlet and spent a significant portion of his career working out the fossil fauna of the Burgess Shale. Combining these two sites within the same field season was a fitting homage.
John Fam, Vancouver Paleontological Society (VanPS) and Dan Bowen, Vancouver Island Palaeontological Society (VIPS), did much of the planning for that Haida Gwaii trip, they too being inspired by Whiteaves papers and the work of James Richardson and George Dawson — as a whole, we were giddy with the prospect of the year ahead.
Rene and I had planned to do both, but in the end, I had to give up the hike to Burgess that year and Rene never made it back to join me in Haida Gwaii.
Rene Savenye |
I take heart that he lived and died doing what he loved most. I got the news a few days later and cried for the loss of a great friend. I am sharing my memory of him with you so that you can remember him, too, and share in the delight and loss of one of the loveliest men to ever walk our planet. His years of teaching, mentoring, encouragement and generosity have helped shape natural science and those who have gone on to make it their passion or career — or happily, both.
Rene's name will not be forgotten to science. His namesake, H. Savenyei, is a lovely fossil halictine bee from Early Eocene deposits near Quilchena, British Columbia — and the first bee body-fossil known from the Okanagan Highlands — and indeed from Canada.
As a school teacher, Rene once taught the, then student, now SFU biology instructor, Rolf Mathewes. Rene passed his scientifically valuable specimen to Mathews, knowing it was important to science. Mathewes brought it to the attention of Bruce Archibald and Michael Engel, who described Rene's bee in the Canadian Journal of Zoology. Their work is a lovely legacy to a wonderful man and a specimen from one of his favourite collecting sites — Quilchena — a small road-cut exposure of the Coldwater beds of the Princeton Group, one of several depositional basins in the Merritt region of south-central British Columbia.
Rene is also remembered in spirit by the British Columbia Paleontological Alliance (BCPA) Rene Savenye Award. It was established in 2003 to honour those who have demonstrated outstanding service to the science of palaeontology or to palaeontological education in British Columbia.
Notable past recipients are a veritable who's who from the Pacific Northwest — Graham Beard of Qualicum in 2005, Charles Helm of Tumbler Ridge in 2011, Pat Trask of Courtenay in 2014, Rod Bartlett in 2016, and Joseph "Joe" Haegert in 2018. I'll share a link to the award below so you can read more at your leisure about Rene and those who bear the award with his name.
About H. Savenyei, (Engel & Archibald, 2003): The type specimen is a fairly well preserved complete adult female preserved with portions of the fore-wings and hind-wings. The specimen is 7.04 millimetres (0.277 in) long with the possibility of alteration in length during fossilization. The sections of the forewing which are preserved are approximately 4.8 millimetres (0.19 in) long and show dark brown to black colouration. The presence of a pygidial plate bordered by setae on the fifth metasomal tergum supports the placement into the Halictidae subfamily Halictinae. Placement into the tribe Halictini is based on the lack of a medial cleft in the fifth tergum.
References:
Archibald, B. & R. W. Mathewes. 2000. “Early Eocene Insects from Quilchena, BC, and their Paleoclimatic Implications.” Canadian Journal of Zoology, Volume 78, Number 6: pp 1441-1462.
Grimaldi, D. 1999. “The Co-radiations of Pollinating Insects and Angiosperms in the Cretaceous.” Annals of the Missouri Botanical Garden. 86: 373-406.
Photo: Halictidae sp.; Archibald and Mathewes 2000: 1453.
Rene Savenye Award: https://bcfossils.ca/rene-savenye-award
Tuesday, 26 January 2021
AINOCERAS HETEROMORPH AMMONITE
This adorable corkscrew-shaped ammonite is an extinct marine mollusc related to squid and octopus. ☺️
Within their shells, they had a number of chambers, called septa, filled with gas or fluid that were interconnected by a wee air tube. By pushing air in or out, they were able to control their buoyancy in the water column.
They lived in the last chamber of their shells, continuously building new shell material as they grew.
As each new chamber was added, the squid-like body of the ammonite would move down to occupy the final outside chamber. Not all ammonites have this whacky corkscrew design. Most are coiled and some are shaped like massive paperclips.
Monday, 25 January 2021
SMILODON: SABER-TOOTHED CAT
Smilodon is a genus of the extinct machairodont subfamily of the felids.
It is one of the most famous prehistoric mammals and the best known saber-toothed cat. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats.
An apex predator, Smilodon used their exceptionally long upper canine teeth to hunt large mammals.
Isotopes preserved in the bones of S. fatalis in the La Brea Tar Pits tell us that they liked to dine on bison (Bison antiquus) and camels (Camelops) along with deer and tapirs. Smilodon is thought to have killed its prey by holding it still with its forelimbs and biting it.
Their razor-sharp incisors were arranged in an arch. Once they bit down, the teeth would hold their prey still and stabilize it while the canine bite was delivered — and what a bite that was. They could open their mouths a full 120 degrees.
Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species.
Illustration. S. fatalis with spotted coat. By Dantheman9758 at English Wikipedia, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=42290827
Sunday, 24 January 2021
FREE SCIENCE TEACHING TOOLS AND IMAGES
In the past, I have found finding images that you need to complete a project can be a bit tricky.
Short of purchasing or borrowing off the internet, teachers and students do not have that many interesting resources available. I have started to include the logo so you can know for sure it is okay to use. If I credit the photo to someone, you would need to ask them first before using it.
I also post over on the Fossil Huntress Facebook page and will begin putting together teaching sets by album of related content. It is mostly palaeontology, earth history, earth science and natural history. Feel free to use what works best for you. Head on over to Fossil Huntress headquarters for links to all sorts of educational goodness. Good luck!
Saturday, 23 January 2021
GIANT PACIFIC OCTOPUS
To support their bodies, these spineless animals — invertebrates — have skeletons made of protein fibres. This flexibility can be a real advantage when slipping into nooks and crannies for protection and making a home in seemingly impossible places.
On the east side of Vancouver Island, British Columbia, Canada, there is an area called Madrona Point where beneath the surface of the sea many octopus have done just that. This is the home of the Giant Pacific Octopus, Enteroctopus dofleini, the largest known octopus species.
The land above is the home of the Snuneymuxw First Nation of the Coast Salish who live here, on the Gulf Islands, and along the Fraser River. They speak Hul'q'umin'um' — a living language that expresses their worldview and way of life. In Hul'q'umin'um' an octopus is sqi'mukw'.
In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, further north on Vancouver Island, octopus or devil fish are known as ta̱k̕wa. I have seen them off the coast of Port Hardy but most of my encounters have been around the mid-island while underwater myself.
I have scuba dived at Madrone Point many times and visited the octopus who squeeze into the eroded sections of a sandstone ledge about 18 metres or 60 feet below the surface. After forty days of mating, the female Giant Pacific Octopus attaches strings of small fertilized eggs to the rocks within these crevices and calls it home for a time — generally five months or 160 days. When I visit, I sometimes bring crab or sea urchin for her to snack on as the mothers guarding these eggs do not leave to hunt, staying ever vigilante protecting their brood from predators.
Octopus are soft-bodied, eight-limbed molluscs of the order Octopoda. The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids.
The oldest fossil octopus at 300 million years old is Pohlsepia mazonensis from Carboniferous Mazon Creek fossil beds in Illinois. The only known specimen resembles modern octopuses with the exception of possessing eight arms and two tentacles (Kluessendorf and Doyle 2000).
Friday, 22 January 2021
DESMOCERAS OF MAHAJANGA
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.
They used their tentacles to snare prey, — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunt today.
Thursday, 21 January 2021
LOTUS FLOWER FRUIT
Lotus Flower Fruit, Nelumbo |
The awesome possums from GRS are based out of North Logan, Utah, USA and have unearthed some world-class specimens. They've found Nelumbo leaves over the years but this is their first fossil specimen of the fruit.
And what a specimen it is! The spectacularly preserved fruit measures 6-1/2" round. Here you can see both the part and counterpart in fine detail. Doug Miller of Green River Stone sent copies to me this past summer and a copy to the deeply awesome Kirk Johnson, resident palaeontologist over at the Smithsonian Institute, to confirm the identification.
There is another spectacular specimen from Fossil Butte National Monument. They shared photos of a Nelumbo just yesterday. Nelumbo is a genus of aquatic plants in the order Proteales found living in freshwater ponds. You'll recognize them as the emblem of India, Vietnam and many wellness centres.
Nelumbo Fruit, Green River Formation |
In the older classification systems, it was recognized under the biological order Nymphaeales or Nelumbonales. Nelumbo is currently recognized as the only living genus in Nelumbonaceae, one of several distinctive families in the eudicot order of the Proteales. Its closest living relatives, the (Proteaceae and Platanaceae), are shrubs or trees.
Interestingly, these lovelies can thermoregulate, producing heat. Nelumbo uses the alternative oxidase pathway (AOX) to exchange electrons. Instead of using the typical cytochrome complex pathway most plants use to power mitochondria, they instead use their cyanide-resistant alternative.
This is perhaps to generate a wee bit more scent in their blooms and attract more pollinators. The use of this thermogenic feature would have also allowed thermo-sensitive pollinators to seek out the plants at night and possibly use the cover of darkness to linger and mate.
So they functioned a bit little like a romantic evening meeting spot for lovers and a wee bit like the scent diffuser in your home. This lovely has an old lineage with fossil species in Eurasia and North America going back to the Cretaceous and represented in the Paleogene and Neogene. Photo Two: Doug Miller of Green River Stone Company
Wednesday, 20 January 2021
SAFFRON GOLD: CROCUS BLOSSOMS
Each crocus flower plucked gently by hand yields three vivid strands of saffron with an acre of laborious work producing only a few pounds.
The challenge of harvesting saffron from crocus and it's high market value dates back to 2100-1600 BC as the Egyptians, Greeks, and the Minoans of Crete all cultivated crocus not as a spice, but as a dye. Roman women used saffron to dye their hair and textiles yellow. The crocus corm has a history of trade throughout Europe that a few pounds of corms served as a loan of gold or jewels. It made it's way into the writing of the Greeks as early as 300 BC where it originated. The precious flower travelled to Turkey and then all the way to Great Britain in the 1500s before making it's way to the rest of the world.
Tuesday, 19 January 2021
INDIGO: NATURAL DYES
Archaeologists have found evidence of textile dyeing dating back to the Neolithic period. In China, dyeing with plants, barks and insects has been traced back more than 5,000 years and looks to be our first attempt at the practice of chemistry.
The essential process of dyeing changed little over time. Typically, the dye material is put in a pot of water and then the textiles to be dyed are added to the pot, which is heated and stirred until the colour is transferred. Sometimes, we use workers with stout marching legs to mix this up.
Traditional dye works still operate in many parts of the world. There is a revival of using natural indigo in modern Egypt — although their indigo dye is mostly imported. The same is true further south in Sudan. They've been importing cloth from Upper Egypt as far back as we have written records and continue the practice of the cloth and dye imports today. Clean white cotton is more the style of western Sudan and Chad, but they still like to throw in a bit of colour.
Traditional Dye Vats |
My guide took me to the top of a building so I could look down on rows and rows of coloured vats. In every other one was a man marching in place to work the dye into the wool. Their legs took on the colour from their daily march in place in huge tubs of liquid dye and sheared wool. This wool would be considered textile fibre dyed before spinning — dyed in the wool — but most textiles are yarn-dyed or piece-dyed after weaving.
Many natural dyes require the use of chemicals called mordants to bind the dye to the textile fibres; tannin from oak galls, salt, natural alum, vinegar, and ammonia from stale urine were staples of the early dyers.
Many mordants and some dyes themselves produce strong odours. Urine is a bit stinky. Not surprisingly, large-scale dyeworks were often isolated in their own districts.
Woad, Isatis tinctoria |
Dyes such as cochineal and logwood, Haematoxylum campechianum, were brought to Europe by the Spanish treasure fleets, and the dyestuffs of Europe were carried by colonists to America.
Throughout history, people have dyed their textiles using common, locally available materials, but scarce dyestuffs that produced brilliant and permanent colours such as the natural invertebrate dyes. Crimson kermes became highly prized luxury items in the ancient and medieval world. Red, yellow and orange shades were fairly easy to procure as they exist as common colourants of plants. It was blue that people sought most of all and purple even more so.
Indigofera tinctoria, a member of the legume or bean family proved just the trick. This lovely plant — named by the famous Swedish botanist Carl Linneaus, the father of formalized binomial nomenclature — grows in tropical to temperate Asia and subtropical regions, including parts of Africa.
The plants contain the glycoside indican, a molecule that contains a nitrogenous indoxyl molecule with some glucose playing piggyback. Indigo dye is a product of the reaction of indoxyl by a mild oxidizing agent, usually just good old oxygen.
To make the lovely blue and purple dyes, we harvest the plants and ferment them in vats with urine and ash. The fermentation splits off the glucose, a wee bit of oxygen mixes in with the air (with those sturdy legs helping) and we get indigotin — the happy luxury dye of royalty, emperors and kings.
While much of our early dye came from plants — now it is mostly synthesized — other critters played a role. Members of the large and varied taxonomic family of predatory sea snails, marine gastropod mollusks, commonly known as murex snails were harvested by the Phoenicians for the vivid dye known as Tyrian purple.
While the extant specimens maintained their royal lineage for quite some time; at least until we were able to manufacture synthetic dyes, it was their fossil brethren that first captured my attention. There are about 1,200 fossil species in the family Muricidae. They first appear in the fossil record during the Aptian of the Cretaceous.
Their ornate shells fossilize beautifully. I'd first read about them in Addicott's Miocene Gastropods and Biostratigraphy of the Kern River Area, California. It's a wonderful survey of 182 early and middle Miocene gastropod taxa.
George E.Radwin and Anthony D'Attilio: The Murex shells of the World, Stanford University press, 1976, ISBN 0-8047-0897-5
Pappalardo P., Rodríguez-Serrano E. & Fernández M. (2014). "Correlated Evolution between Mode of Larval Development and Habitat in Muricid Gastropods". PLoS ONE 9(4): e94104. doi:10.1371/journal.pone.0094104
Miocene Gastropods and Biostratigraphy of the Kern River Area, California; United States Geological Survey Professional Paper 642 This article incorporates text from this source, which is in the public domain.
Monday, 18 January 2021
Sunday, 17 January 2021
GONDWANA: DEEP TIME
Gondwana was a supercontinent that existed from the Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic (about 180 million years ago), with the final stages of a breakup, including the opening of the Drake Passage separating South America and Antarctica occurring during the Eocene.
Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. Gondwana dominated the southern hemisphere for more than 400 million years. It took until 1861 for us to recognize the clues in our modern placement of rocks and fossils
Saturday, 16 January 2021
OIL IN WATER BEAUTY
Euhoplites is an extinct ammonoid cephalopod from the Lower Cretaceous, characterized by strongly ribbed, more or less evolute, compressed to inflated shells with flat or concave ribs, typically with a deep narrow groove running down the middle.
In some, ribs seem to zigzag between umbilical tubercles and parallel ventrolateral clavi. In others, the ribs are flexious and curve forward from the umbilical shoulder and lap onto either side of the venter.
Its shell is covered in the lovely lumps and bumps we associate with the genus. The function of these adornments are unknown. I wonder if they gave them greater strength to go deeper into the ocean to hunt for food.
They look to have been a source of hydrodynamic drag, likely preventing Euhoplites from swimming at speed. Studying them may give some insight into the lifestyle of this ancient marine predator. Euhoplites had shells ranging in size up to a 5-6cm.
We find them in Lower Cretaceous, middle to upper Albian age strata. Euhoplites has been found in Middle and Upper Albian beds in France where it is associated respectively with Hoplites and Anahoplites, and Pleurohoplites, Puzosia, and Desmoceras; in the Middle Albian of Brazil with Anahoplites and Turrilites; and in the Cenomanian of Texas.
This species is the most common ammonite from the Folkstone Fossil Beds in southeastern England where a variety of species are found, including this 37mm beauty from the collections of José Juárez Ruiz.
Friday, 15 January 2021
FOLKSTONE GAULT CLAY AMMONITES
This matrix you see here is the Gault Clay, known locally as the Blue Slipper. This fine muddy clay was deposited 105-110 million years ago during the Lower Cretaceous (Upper and Middle Albian) in a calm, fairly deep-water continental shelf that covered what is now southern England and northern France.
Lack of brackish or freshwater fossils indicates that the gault was laid down in open marine environments away from estuaries. The maximum depth of the Gault is estimated 40-60m a figure which has been reached by the presence of Borings made by specialist Algal-grazing gastropods and supported by a study made by Khan in 1950 using Foraminifera. Estimates of the surface water temperatures in the Gault are between 20-22°c and 17-19°c on the seafloor. These estimates have been reached by bulk analysis of sediments which probably register the sea surface temperature for calcareous nanofossils.
It is responsible for many of the major landslides around Ventnor and Blackgang the Gault is famous for its diverse fossils, mainly from mainland sites such as Folkestone in Kent.
Folkestone, Kent is the type locality for the Gault clay yielding an abundance of ammonites, the same cannot be said for the Isle of Wight Gault, however, the south-east coast of the island has proved to be fossiliferous in a variety of ammonites, in particular, the Genus Hoplites, Paranahoplites and Beudanticeras.
While the Gault is less fossiliferous here on the island it can still produce lovely marine fossils, mainly ammonites and fish remains from these muddy mid-Cretaceous seas. The Gault clay marine fossils include the ammonites (such as Hoplites, Hamites, Euhoplites, Anahoplites, and Dimorphoplites), belemnites (such as Neohibolites), bivalves (notably Birostrina and Pectinucula), gastropods (including the lovely Anchura), solitary corals, fish remains (including shark teeth), scattered crinoid remains, and crustaceans (look for the crab Notopocorystes).
Occasional fragments of fossil wood may also be found. The lovely ammonite you see here is from the Gault Clays of Folkstone. Not all who name her would split the genus Euhoplites. There’s a reasonable argument for viewing this beauty as a very thick form of E. loricatus with Proeuhoplites being a synonym of Euhoplites.
Jack Wonfor shared a wealth of information on the Gault and has many lovely examples of the ammonites found here in his collections. If you wish to know more about the Gault clay a publication by the Palaeontological Association called 'Fossils of the Gault clay' by Andrew S. Gale is available in Dinosaur Isle's gift shop.
There is a very good website maintained by Fred Clouter you can look at for reference. It also contains many handy links to some of the best fossil books on the Gault Clay and Folkstone Fossil Beds. Check it out here: http://www.gaultammonite.co.uk/
Thursday, 14 January 2021
NAOMICHELYS SPECIOSA OF THE HASLAM
Naomichelys speciosa, a new Helochelydrid turtle from the Trent River |
Naomichelys is known from numerous specimens throughout western North America, most notably the holotype partial shell from the Early Cretaceous Cloverly Formation of Montana and a complete skeleton from the Antlers Formation of Texas.
The Cloverly Formation includes a number of vertebrate fossils including a diverse assemblage of dinosaur fossils. the site was designated as a National Natural Landmark by the National Park Service in 1973.
Naomichelys is a member of the family Helochelydridae. We find their fossilized remains in Late Jurassic to Late Cretaceous deposits in North America and Europe. Within North America, only the species Naomichelys speciosa is known from relatively complete material which makes comparisons between specimens from other localities challenging. Phil Currie along with co-authors Matthew J. Vavrek, Derek W. Larson, Donald B. Brinkman and Joe Morin described a new species of Helochelydrid terrestrial turtle found on the Trent River near Courtenay, British Columbia.
The new genus and species of helochelydrid turtle were based on a relatively complete shell from the marine Haslam Formation (Santonian) of Vancouver Island, British Columbia, Canada.
The new species is characterized by several distinctive shell features, notably a forward curving process on the anterior portion of the hyoplastra, strongly distinguishing it from N. speciosa. The shell is relatively small but does appear to be from a fully grown individual, suggesting that the species was generally much smaller than other known helochelydrids.
Previously most records of helochelydrids in North America had been assigned to N. speciosa, regardless of actual diagnosable characters. The presence of an additional species of helochelydrid from North America indicates that a greater diversity of the taxon was present than was previously recognized. While the interspecific relationships of helochelydrids remain difficult to fully assess, due to the lack of well-preserved specimens, this new species provides additional geographic and phylogenetic data that aids our understanding of this enigmatic group.
Monday, 11 January 2021
Sunday, 10 January 2021
SWIMMING TRIASSIC SEAS: ALBERTONIA
Triassic Fossil Fish, Albertonia sp. |
Specimens of this beauty have been found in the Vega-Phroso Siltstone Member of the Sulphur Mountain Formation near Wapiti Lake in British Columbia and the Lower Triassic Montney Formation of Alberta.
Early Triassic fish have been described from several outcrops in the Western Canada Sedimentary Basin of the Rocky Mountains. The best known and most prolific of these are from sites near Wapiti Lake in northeastern British Columbia. Here specimens of bony fish with their heavy ganoid and cosmoid scales are beautifully preserved. Four genera of Early Triassic fishes — the ray-finned actinopterygians Albertonia, Bobasatrania, Boreosomus, and the lobe-finned coelacanth (sarcopterygian), Whiteia — are found in abundance in the Wapiti Lake exposures.
This particular species is one of my favourites. Albertonia is a member of the ganoid fish family Parasemionotidae, which is amongst the most advanced and abundant of Triassic subholostean families of fish. The preservation here really shows the beauty of form of this species who likely died and was preserved in sediment at the bottom of an ocean with an anoxic environment.
These fellows lived in deep marine waters, dining on plankton & other small organisms. Most specimens are 35-40cm in length. They have a large, sail-shaped dorsal fin and rather smallish ventral fins. Their pectoral fins were incredibly long compared to the rest of the body, and they too resembled sails. The preservation here is quite remarkable with each square-shaped scale preserved in minute detail.
Friday, 8 January 2021
Thursday, 7 January 2021
NORTH SEA DOLPHIN VERT
Brown Bank, North Sea, Pleistocene Dredging Area |
It has long been suspected that the southern North Sea plain may have been home to thousands of people, and chance finds by fishermen over many decades support this theory.
A concentration of archaeological material, including worked bone, stone and human remains, has been found within the area around the Brown Bank, roughly 100 km due east from Great Yarmouth and 80 km west of the Dutch coast. The quantities of material strongly suggest the presence of a prehistoric settlement. As such the Brown Bank provides archaeologists with a unique opportunity to locate a prehistoric settlement in the deeper and more remote areas of the North Sea, known today as Doggerland.
Until sea levels rose at the end of the last Ice Age, between 8-10,000 years ago, an area of land connected Great Britain to Scandinavia and the continent. It has long been suspected that the southern North Sea plain was home to thousands of people, and chance finds by fishermen over many decades support this theory.
Over the past decades a concentration of archaeological material, including worked bone, stone and human remains, has been found within the area around the Brown Bank, roughly 100 km due east from Great Yarmouth and 80 km west of the Dutch coast.Prospecting for such a settlement within the North Sea is a challenging activity. Multiple utilities cross the area, bad weather is frequent, and visibility underwater is often limited. Given these challenging conditions, researchers on the Belgian vessel, RV Belgica, used acoustic techniques and physical sampling of the seabed to unravel the topography and history of the areas chosen for the survey.
During the survey, the team used a novel parametric echosounder from the Flanders Marine Institute (VLIZ). This uses sonar technology to obtain images of the sub-bottom with the highest possible resolution and was combined with the more traditional “sparker” seismic source to explore deeper sediments. On the Brown Bank, the Belgica also deployed a grab and a Gilson dredge for sampling near-surface stratigraphy. Video footage was collated using VLIZ’s dedicated video frame and a simpler GoPro mounted on the Gilson dredge. A video showing the equipment in operation on the expedition can be seen at https://youtu.be/sGKfyrDCtmw
Additional reading: http://www.vliz.be/en/press-release/update-research-prehistoric-settlements-North-Sea
Wednesday, 6 January 2021
PREDATORY OLIGOCENE DOLPHIN
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, a parvorder or suborder of cetaceans that includes dolphins, porpoise and our toothed whale friends and includes all the whales which eat prey larger than plankton. This toothy group includes sperm whales, beaked whales, river and oceanic dolphins, pilot whales and their cetacean brethren with teeth rather than the baleens we find in Mysticeti whales.
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 tailstock, 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