Diplomoceras sp. |
Sunday, 4 July 2021
DIPLOMOCERAS OF HORNBY / JA-DAI-AICH
Thursday, 1 July 2021
OH CANADA — CANADA'S PLANNED, FUNDED, HIDDEN & ONGOING GENOCIDE
Murdered & Missing Children Art by Roy Vickers |
You likely know about the Residential School System in Canada — and also the USA. You may have heard the stories of what went on there.
Recently, the media has been flooded by the deaths and unmarked graves of children. We weep for them as a nation.
And you likely feel sadness or outrage for these events that feel like they should be deep in the past — except they weren't.
The 'Indian' Residential Schools were schools built and funded by the government of Canada and run by various religious groups between 1831 (most in western Canada opened around 1860-1870s) and into the 1990s — the last closed in 1997.
The first school to open was the Mohawk Institute Residental School in 1828. They began to receive federal funding in 1831. The last school to close was Kivalliq Hall in Rankin Inlet, in what is now Nunavut, which closed in 1997; it became an IRSSA-recognized school in 2019 following a court ruling, which is why earlier accounts describe the last school closing in 1996.
Yes, recent history. The most important question is not when were these schools built — but why were these schools built?
To answer that we need to think about Canada as a young nation. Canada was meant to be a conquered land under British rule. The 'savages' having served their purpose in the (arguably mutually beneficial) fur trade and providing 'true novelty' in exhibitions like the 1893 Chicago World Fair, now needed to set their (silly, primitive) traditional ways aside and get on with the business of being white — or at least, dressing 'normal', speaking English (or French), adopting Western civilization practices. All primitive 'religious' paraphernalia had been stolen by this point — coppers, masks, etc. — and the practice of potlatch forbidden by law.
The goal by the 1870s was that the Indigenous adults living at that time would be the LAST of the 'savages' and their children would be "educated = assimilated" into Western society. The churches running the schools were completely empowered to "beat them into submission" so that the children would "assimilate or die."
So, to the world in our outward-facing messaging and in our history books, Canada did this kind and generous thing of building and funding schools to give these precious young children a much-needed education. We did this because, we as Canadians, are good guys.
All of this is hard to believe given Canada's global image. We are the quiet, polite folk with the funny accent. What is being described sounds more like the work of the Nazi's extermination pogroms during the Second World War.
You will be surprised to learn, then, that the term "Final Solution" was coined by Indian Affairs Superintended Duncan Campbell back in 1910 as he articulated how he envisioned solving the "Indian Problem" in Canada.
"It is readily acknowledged that Indian children lose their natural resistance to illness by habitating so closely in these schools and that they die at a much higher rate than in their villages. But this alone does not justify a change in the policy of this Department, which is geared towards the final solution of our Indian Program."
That statement was written by Duncan C. Scott in April 1910, in his capacity as the Superintendent of Indian Affairs to General-Major D. McKay, British Columbia's Indian Agent (Department of Indian Affairs Archives, RG 10 series).
Indian Residential Schools operated in Canada from 1831-1996 |
Some children and parents did want their kids to go to school for an education. And some had schools close to home that they could have or would have attended but they could not.
Under the Indian Act of Canada, every First Nation (Metis & Inuit still had to but not under this Act) child had to attend a residential school (built far from home and run by the church) by law.
It was illegal for these same children to attend ANY other educational institution. Why would we care where they were educated? It would actually have been more economical to have them live at home and attend school.
If education was the goal, why have this written into law?
History books will need to be amended to correct the untruths, the systemic re-writing, editing and white-washing of history. It is my hope that they include exact copies of these documents and not a paraphrased interpretation. The original wording is chilling. When you do get the chance to read the original documentation, please do.
So, 150,000 or more 'Indians' — First Nation, Inuit and Metis — were forced to attend these residential schools, not to give them an education but to deliberately strip them of their culture. It wasn't lost as a by-product of attending, it was the sole reason for their attending.
We may find that the number exceeds 150,000 as there are pretty good Census records from that time in Canada's history. Even so, 150,000 is every child they could get their hands on from the age of 4-16 living in our country.
We used to paint a picture that children were lucky to attend and that their parents wanted them to attend. This, too, is a lie. It was illegal not to send your children. Children were beaten, tortured and raped. Beaten for speaking their native tongue.
It was illegal to protest your children being taken. It was illegal to even seek legal advice regarding the matter.
We feel sadness today for the few hundred unmarked graves we are finding. This mild 'there-there, that is tragic, lets put up a nice headstone, take a few silent minutes and enjoy a cup of tea... and move on' attitude by our government is not surprising.
We're Canada. We're used to being the good guys. We wrote our history to be the good guys.
But this was G.E.N.O.C.I.D.E. — organized, premeditated, structured and funded genocide in partnership between the church and the government of Canada.
"Genocide — the deliberate killing of a large number of people from a particular nation or ethnic group with the aim of destroying that nation or group."
Canada was dealing with "the Indian problem" back in the 1800s. Lands were set aside (very similar to how we treat animals in a zoo...) and groups of First Nations, Inuit and Metis were moved onto these 'reserves.'
Now, if you want to wage a successful war, you either need to kill everyone outright (though spare a few as slaves) or inter-marry with the population. Given that the first forays by settlers were to trade, it was the latter strategy that was chosen — except it was too slow.
I have more direct quotes that I will dig out to share with you about our governments' views on "the Indian Problem" and the deliberate 'assimilate or die pogrom' as delivered through the Residential School System — think of it as Smallpox 2.0 (infected people and blankets were sent into communities to infect and kill).
We feel sad for the #215 and the hundreds of unmarked graves we are finding. I think the death toll exceeds 50,000. Not all of those graves will be unmarked. Some of those children are in local cemeteries, some were cremated in Indian Hospitals (where medical experimentation was done), some in unmarked graves, but I truly think we are just at the tip of the iceberg.
Realistically, it may be as high as 75,000. There are newspaper reports from way back in the day that speak to a 50% death rate at the schools. Yes, 50%.
That is just the number of dead and buried. What about abused and tortured? Raped and beaten? That number is at or near — or exceeds — 150,000.
So, what happens now? There will be apologies. There will be an inquiry. Many people will buy and wear orange shirts as an act of solidarity — and I thank those who do. For a few weeks, it will saturate the news.
Canada will try to sidestep their active participation and coordination of genocide. Canadian political groups may use this tragedy to help bolster their image for re-election. Good for them. I don't really care why they do the right thing just that they do the right thing.
"This was a sad part of our history (trying to put it in the past) for which we apologize (on behalf of folk long dead so what can we really do about it?) and move forward as a nation (with some parades and emotionally charged solidarity)...
But this doesn't go away with an apology and a kumbaya.
So, the Canadian government will continue to apologize again and again — AND try to slide the blame over to the church, particularly the Catholic Church as they operated about 70% of all of these assimilation centres and because they are perceived to be immune to the law, in many cases above the law, and incredibly well-funded — plus they are well-known bastards with a long history of being hated — the perfect pre-made scapegoat.
So, records will be slow to be produced. Records that support a narrative of this being 'all the churchs' fault" will likely be more readily found and produced than those which directly implicate our government. Some of the records found will be destroyed.
But the truth will come out. Survivor stories will be told.
And it is not just the Catholic Church — though they are a particularly vicious organization with a very long history of abuse and paedophilia — exactly who you would NOT want to entrust with children. These are the same self-righteous charmers who brought us the Inquisition, an infamous history of torture and persecution that goes back to the 12th century. I am not a fan.
I have Christian and Catholic friends whom I love. I love individuals but not institutions who do not hold themselves to account. Love them or hate them, these organizations will be thrown under the bus as they deserve.
If you read canadahistory.ca, you'll see "Western Canada's Treaties were intended to provide frameworks for respectful coexistence."
In Canada, Treaties represent the source of First Nation's peoples' unique nation-to-nation relationship with the Crown. When I first read that 'the treaties were meant as a means of respectful coexistence,' I thought, 'that sounds about right.' Then I thought more of the histories. It sounds great, but it is not true.
I do not know if Canada is capable of honestly dealing with this shame, and guilt as a nation.
Groups protect their own. I worry that those that do come across evidence may destroy it 'for the collective good.' Destruction of evidence is a very common practice. I think we need to acknowledge that we cannot be trusted as a nation to investigate this on our own. I would like the UN as a neutral third party to work with us as a nation as we uncover our historical truths.
What will not happen — though I would very much love it to — is for every church involved to have their church property revoked (not burned to the ground as is happening in our country), all of their records confiscated and made public (as appropriate) and all of the known abusers still working with them abusing the next generation of children, brought to justice.
Every Canadian should read the Truth and Reconciliation Commission's Final Report. This should be taught in schools. Groups should be brought together to discuss this as a nation and work together to plan the next steps.
Folk around the world should read it, too. Canada has a long history of missing and murdered women and children. The Murdered and Missing Indigenous Women and Girls Inquiry did good work and produced 231 Calls to Justice.
These recent news stories will finally be the boot to the neck of Canada to acknowledge the hidden history of this planned, funded genocide by the government of Canada. These recently discovered remains will be the final pebble that creates an avalanche.
This is a powerful time in our history. This is our chance to do what is right — what is just. This is a chance to truly listen and take steps to collectively mend ourselves as a nation of nations. Sadness and outrage are natural responses to this truth. I hope you, too, feel a passionate desire for justice — for Truth & Reconciliation.
Thank you to Roy Vickers for sharing this powerful image to help gain awareness and create dialogue for lasting change.
Wednesday, 30 June 2021
FOSSILS, TEXTILES AND URINE
Yorkshire Coast |
The Yorkshire Museum was given this important ichthyosaur fossil back in 1857 when alum production was still a necessary staple of the textile industry. Without that industry, many wonderful specimens would likely never have been unearthed.
These quarries are an interesting bit of British history as they helped shape the Yorkshire Coast, created an entirely new industry and gave us more than a fixative for dyes. With them came the discovery of many remarkable fossil specimens and, oddly, local employment in the collection of urine.
In the 16th century, alum was essential in the textile industry as a fixative for dyes.
Fashion in Medieval Livonia (1521): Albrecht Dürer |
This century saw the rise of the ruff, which grew from a mere ruffle at the neckline to immense, slightly silly, cartwheel shapes. They adorned the necklines of the ultra-wealthy and uber-stylish men and women of the age.
At their most extravagant, ruffs required wire supports and were made of fine Italian reticella, a cutwork linen lace.
16th Century Fashion / Ruff Collars and Finery |
The Pope held a tidy monopoly on the industry, supplying both alum and the best dyes. He also did a nice trade in the colourful and rare pigments for painting. And for a time, all was well with dandy's strutting their finery to the local fops in Britain.
All that changed during the Reformation. Great Britain, heathens as they were, were cut-off from their Papal source and found themselves needing to fend for themselves.
The good Thomas Challoner took up the charge and set up Britain's first Alum works in Guisborough. Challoner looked to paleontology for inspiration. Noticing that the fossils found on the Yorkshire coast were very similar to those found in the Alum quarries in Europe, he hatched a plan to set-up an alum industry on home soil. As the industry grew, sites along the coast were favoured as access to the shales and subsequent transportation was much easier.
Alum House, Photo: Joyce Dobson and Keith Bowers |
At the peak of alum production, the industry required 200 tonnes of urine every year. That's the equivalent of all the potty visits of more than 1,000 people. Yes, strange but true.
The steady demand was hard to keep up with and urine became an imported resource from markets as far away as London and Newcastle upon Tyne in the northeast of England. Wooden buckets were left on street corners for folk to do their business then carted back to the south to complete the alum extraction process. The urine and alum would be mixed into a thick liquid. Once mixed, the aromatic slosh was left to settle and then the alum crystals were removed.
I'm not sure if this is a folktale or plain truth, but as the story goes, one knows when the optimum amount of alum had been extracted as you can pop an egg in the bucket and it floats on its own.
Alum House. Photo: Ann Wedgewood and Keith Bowers |
There are many sites along the Yorkshire Coast which bear evidence of the alum industry. These include Loftus Alum Quarries where the cliff profile is drastically changed by extraction and huge shale tips remain.
Further South are the Ravenscar Alum Works, which are well preserved and enable visitors to visualize the processes which took place. The photos you see here are of Alum House at Hummersea. The first shows the ruin of Alum House printed on a postcard from 1906. The second (bottom) image shows the same ruin from on high with Cattersty Point in the background.
The good folk at the National Trust in Swindon are to thank for much of the background shared here. If you'd like to learn more about the Yorkshire area or donate to a very worthy charity, follow their link below.
Reference: https://www.nationaltrust.org.uk/yorkshire-coast/features/how-alum-shaped-the-yorkshire-coast
Tuesday, 29 June 2021
TEMNODONTOSAURUS CRASSIMANUS
Temnodontosaurus crassimanus |
The fellow you see here is the Type Specimen for the species and he lives on display in the Yorkshire Museum. As the reference specimen for the species, all hopeful specimens that may belong to this species are checked against the Type Specimen to see if they share diagnostic features.
The Yorkshire Museum was given this important ichthyosaur fossil back in 1857, albeit in bits and pieces. The first bits of fossil bones were found near Whitby on the North Yorkshire coast by workmen quarrying alum. They recognized the bones as belonging to a fossilized reptile and alerted local authorities who in turn alerted the good Master Owen.
It was quite an undertaking to recover as it was found in more than fifty pieces in massive shale blocks and the alum quarry was active at the time. Alum quarrying helped share the Yorkshire Coast as an important staple of the textile industry going back to the 16th-century. By the 1860s, alum quarrying was slowing down. The ability to manufacture synthetic alum by 1855 had shifted the industry and it died out entirely by 1871. Lucky for us, the last years of alum production gifted us this well-preserved eight-metre specimen, one of the largest ichthyosaurs ever discovered in the UK.
Paleo-coordinates: 54.5° N, 0.6° W: paleocoordinates 42.4° N, 9.3° E
Monday, 28 June 2021
CAMBRIAN MYSTERIES OF THE CANADIAN ROCKIES
Mount Stephen, Canadian Rockies |
Here, for more than a century, palaeontologists have been exploring over a dozen geologic outcrops that speak of a world when arthropods ruled the seas.
The rocks we walk across are made of shale, thin-bedded limestone, and siltstone deposited during the Middle Cambrian — 513 to 497 million years ago. And these are no ordinary rocks for what they contain — exceptionally preserved soft-bodied fossils of the Burgess Shale biota.
Charles Doolittle Walcott will be forever remembered for his extraordinary 1909 discovery of the Middle Cambrian Burgess Shale of Yoho National Park in southern British Columbia — delivering to the world one of the most important biota of soft-bodied organisms in the fossil record. Here we find a fairly complete look at an ancient ecosystem with algae, grazers and filter feeders, scavengers and active predators. Remarkably, soft-bodied organisms make up 98% of individuals and 85% of the genera. These animals lived and died in the deep waters at the base of what would later become the Cathedral Escarpment.
In 1908, Walcott wrote, "Nearly every fragment of shale found on the slopes from 2000 to 2600 feet above Field has fossils upon it; not only fragments but usually entire specimens of trilobites.” It was for this reason he returned the following year to collect and the rest, as they say, is history.
The sheer volume and level of preservation were unknown at the time. Walcott's material came from a single section on the west side of the ridge between Mount Wapta and Mount Field and was collected from the main quarry in the Phyllopod bed and the smaller Raymond quarry some 23 m above.
The Burgess Shale section occurs in the lower two-thirds of the Stephen Formation where the basinal shales abut against the steep face of the adjacent dolomite reef of the Cathedral Formation. The conditions necessary for the preservation of the soft parts of the organisms appear to have been controlled by the proximity of this reef front. Away from the reef front, exceptional preservation is less common.
A view to Mount Stephen, Canadian Rockies |
Des Collins speculated that more localities of soft-bodied fossils might be found in the basinal shales near these contacts, and, indeed, a few indications were later reported by Aitken and McIlreath (1981) along the line of the Escarpment.
In 1981 and 1982, we expanded our knowledge of the region. Des Collins and others organized fieldwork that led to the discovery of about a dozen new localities, which Collins et al. published in 1983.
The most promising of the new localities occurred in a large in situ block of pale grey-blue siliceous shale about 1500 m southwest of the outcrop of the Cathedral Escarpment on the north shoulder of Mount Stephen.
This is about 5 km almost directly south of the Burgess Shale quarries. The site was excavated by a Royal Ontario Museum party in the summer of 1983. Further fieldwork in 1986 led to the discovery of the arthropod Sanctacaris was first described by Briggs and Collins in 1988.
Sanctacaris uncata, Mount Stephen Fossil Beds |
The stratigraphic level where the block occurred is characterized by the trilobite, Glossopleura, which is the local zone fossil for the basal part of the basinal Stephen Formation (Fritz, 1971).
In the Stephen Formation section of about 1000 m to the north on Mount Stephen measured by Fritz, the top of the Glossopleura Zone is 40 m below the level equivalent to the main Burgess Shale quarry.
The block excavated was at least 40 m below the top of the Glossopleura Zone. This puts it 80 m or more stratigraphically below the level of the Burgess Shale Phyllopod bed.
The faunal assemblage from the block is dominated by the arthropods, Alalcomenaeua and Branchiocaris, which are very rare in the Burgess Shale. Many other Burgess Shale animals were found (Collins et al. 1983) but surprisingly not the most common — Marrella. They did find many new forms and published their finds in 1986 (Collins, 1986). By all accounts, this fauna is distinct from those in the Burgess Shale — and a shade older.
But as we learn and gain insight, we also realize how much we have yet to learn. These outcrops help us to gain an understanding of the biology, ecology, diversity and evolution of Cambrian animals in a way that other Cambrian sites cannot. Without this insight, we would have a very limited view of the Cambrian Explosion and see only the shelly fossil assemblages. The unique conditions in the Burgess Shale record species that under typical circumstances, would never have fossilized and would be lost to us forever.
There has been no end of mysteries and riddles to be solved in the designating and correlating units within the Stephen Formation, Burgess Shale Formation, and the Cathedral Formation. Much of the controversy stems from the extensive faulting in the area and especially from environmental (facies) differences between the stratigraphic units.
There are shelf platform sequences that include shallow water inner detrital belt, middle carbonate belt, and carbonate shelf edge facies, as well as deeper water (basinal) outer detrital belt facies. These have all have posed problems in correlation and descriptions of the formations in the area.
What used to be known as the Stephen Formation is now restricted to what was known as the "thin" Stephen Formation. The Stephen Formation now includes the Narao and Wapituk Members. What was formerly the "thick" Stephen Formation (basinal Stephen) is now called the Burgess Shale Formation.
Pirania sp., extinct sea sponges, Burgess Shale |
The Burgess Shale is a UNESCO World Heritage site. The Burgess Shale and Stephen Formations outcrop mainly in Banff and Yoho National Parks in the Alberta-British Columbia border area. All known outcrops are in Canada's Rocky Mountain Parks, so collecting is strictly forbidden.
While you cannot collect in the parks, you can join in on a guided tour to hike, explore, capturing the beautiful scenery and fossils with your camera and through rubbings. If you fancy a hike to these exalted cliffs, follow the link below.
If an armchair visit is more your thing, pick up a copy of, A Geoscience Guide To The Burgess Shale. This illustrated guide immerses the reader in the history, geology, environment and, most importantly, fossils of the Burgess Shale in an easy-to-read, concise summary of life as it was over 500 million years ago. Excellent colour images of 3D interpretations of the organisms and photos of the fossils make this resource a must-have for anyone interested in the Burgess Shale.
Burgess Shale Hikes: https://www.burgess-shale.bc.ca/burgess-shale-hikes/ / Toll free: 1 (800) 343-3006; Tel: 1 (250) 343-6006; Email: info@burgess-shale.bc.ca
A Burgess Shale Primer: History, Geology and Research Highlights; Jean-Bernard Caron & Dave Rudkin: https://www.rom.on.ca/sites/default/files/imce/burgess_shale_primer.pdf
References: Palaeontology, Vol 31, Part 3. 1988, pp 779-798, pls 71-73) was discovered by Collins (1986),http://palaeontology.palass-pubs.org/pdf/Vol 31/Pages 779-798.pdf
Image: Reconstruction of Sanctacaris uncata, a Cambrian Habeliidan arthropod (stem-Chelicerata: Habeliida). by Junnn11 @ni075; Pirania sp. & photos: @Fossil Huntress
Sunday, 27 June 2021
IN PRAISE OF FOSSIL LAGERSTÄTTEN
A Lagerstätte is a sedimentary deposit with extraordinary fossils with exceptional preservation — sometimes preserving soft tissues when we are very lucky.
When you see a specimen and it makes you go 'whoah' — that is a good indication that you are likely seeing one of the wonderfully preserved goodies from these marvellous sites.
There are about 50 sites we collectively describe as Lagerstätten — though there are many more sites that could reasonably be argued for — and they are. The list below gives you a place to start but it is by no means exhaustive and will grow as more sites are found and explored.
If you are curious about checking out these wonderfully preserved sites, pay a visit to @FossilBonanza, the Twitter home of Andy, an educator at NHMU. On both his @FossilBonanza Twitter stream and his podcast of the same name, Andy gushes about Lagerstätten from around the globe.
He's also created a rather clever interactive map of the world’s Lagerstätten divided by time period. You can visit here: https://maphub.net/FossilBonanza/Lagerstatte. To listen to the Fossil Bonanza Podcast: https://podcasts.apple.com/.../fossil-bonanza/id1535645906
Saturday, 26 June 2021
CAMBRIAN BIVALVED ARTHROPODS
The image you see here is a composite from many publications that have been pulled together into a full composite with scaling by the talented Alejandro Izquierdo, an evolutionary biologist fast-tracking his way to a PhD at the University of Toronto's Invertebrate Palaeontology lab. The Canadaspis shadow you see here is from Derek Brigg's 1975 reconstruction. I have modified the image further still and you are welcome to use it as a teaching tool — but please do credit Alejandro as he did all the heavy lifting in putting it together.
I caught up with Alejandro this week to ask about the origins of this image — which I have modified a bit further still — and to talk about Pakucaris apatis and Fibulacaris nereidis — two recent additions to our knowledge of bivalved arthropods. Both show us how "bizarre" some of these animals can be. Pakucaris presents different features — frontal filaments, a pygidium — which may be important in the future to understand early arthropod evolution.
Beyond his research into our Cambrian friends, Alejandro is a science writer and prog-rock aficionado. Should you want to catch up with him, find him on Twitter @trichodes or for all sorts of yummy evolutionary biology goodness seek out the site he co-runs with Marc Riera, an ecologist and PhD student looking at biological invasions at CREAF — a public research centre that exists as a consortium between different public entities — administrations, universities, and research centres and institutes. You can find Marc @bitoptera and their combined work at @ElephaBacteria.
Do visit their delightful website — On elephants and bacteria — a feast of interdisciplinary topics that gather evolutionary biology, astronomy, history with a mission to advance scientific thinking. It is well worth exploring. Here is the link: https://onelephantsandbacteria.net/
Friday, 25 June 2021
CHELICERATES: EURYPTERIDS, SPIDERS AND HORSESHOE CRABS
Sanctacaris uncata, (Briggs & Collins, 1988) |
Sanctacaris is proof positive that chelicerates, although rare, were present in our Middle Cambrian seas.
Even at this early stage of evolution, Sanctacaris had the number and type of head appendages found — though in modified form — in eurypterids and xiphosurids, the major Palaeozoic groups that succeeded it. Even more interesting is that Sanctacaris had all the characteristics of later chelicerates except chelicerae — placing this early arthropod in a primitive sister group of all other chelicerates.
An extinct marine creature half a billion years old may sound otherworldly, but you know some of their more well-known marine brethren — sea spiders, the sexy eurypterids, chasmataspidids and horseshoe crabs — and some of their terrestrial cousins — spiders, scorpions, harvestmen, mites and ticks.
They are grouped together because, like all arthropods, they have a segmented body and segmented limbs and a thick chitinous cuticle called an exoskeleton. Add those characteristics to a body system with two body segments — a cephalothorax and an abdomen.
Like all arthropods, chelicerates' bodies and appendages are covered with a tough cuticle made mainly of chitin and chemically hardened proteins.Since this cannot stretch, the animals must moult to grow. In other words, they grow new but still soft cuticles, then cast off the old one and wait for the new one to harden.
Until the new cuticle hardens the animals are defenceless and almost immobilized.
This also helps to explain why you find so many cephalons or moulted head shields — or whatever else our good arthropod friends shed and regrow — in the field and far fewer body fossils of the whole animal.
Some chelicerate are predatory animals that patrol the warm waters near thermal vents. They can be found feeding upon other predators and fish. Although the group were originally solely predatory, they have diversified to use all sorts of feeding strategies: predation, parasitism, herbivory, scavenging and dining on bits of decaying organic matter.
Although harvestmen can digest solid food it is more akin to a mashed pulp by the time they do. The guts of most modern chelicerates are too narrow to digest solid food, instead, they generally liquidize their chosen meal by grinding it with their chelicerae and pedipalps then flooding it with digestive enzymes.
To conserve water, air-breathing chelicerates excrete waste as solids that are removed from their blood by Malpighian tubules, structures that also evolved independently in insects — another case of convergent evolution.
The evolutionary origins of chelicerates from the early arthropods have been debated for decades. And although there is considerable agreement about the relationships between most chelicerate sub-groups, the inclusion of the Pycnogonida in this taxon has recently been questioned and the exact position of scorpions is still controversial — though they have long been considered the most primitive or basal of the arachnids.
We still have much to explore to sort out their evolutionary origins and placement within the various lineages but we will get there in time.
Image One: Reconstruction of Sanctacaris uncata, a Cambrian Habeliidan arthropod (stem-Chelicerata: Habeliida). by Junnn11 @ni075; Image Two: Chelicerata by Fossil Huntress
Aria C, Caron JB (December 2017). "Mandibulate convergence in an armoured Cambrian stem chelicerate". BMC Evolutionary Biology. 17 (1): 261. doi:10.1186/s12862-017-1088-7. PMC 5738823. PMID 29262772.
Legg DA (December 2014). "Sanctacaris uncata: the oldest chelicerate (Arthropoda)". Die Naturwissenschaften. 101 (12): 1065–73. doi:10.1007/s00114-014-1245-4. PMID 25296691.
Briggs DE, Collins D (August 1988). "A Middle Cambrian chelicerate from Mount Stephen, British Columbia" (PDF). Palaeontology. 31 (3): 779–798. Archived from the original (PDF) on July 16, 2011. Retrieved April 4, 2010.
Briggs DE, Erwin DH, Collier FJ (1995). Fossils of the Burgess Shale. Washington: Smithsonian Institution Press. ISBN 1-56098-659-X. OCLC 231793738.
Thursday, 24 June 2021
FIBULACARIS NEREIDIS: A NEW BIVALVED CAMBRIAN ARTHROPOD
Fibulacaris nereidis / Artwork by Danielle Dufault @MesozoicMuse |
The origin of the arthropod carapace, an enlargement of cephalic tergites, can be traced back to the Cambrian period. Even so, its disparity and evolution are still not fully understood. It is the detailed study of species such as this new ‘bivalved’ arthropod, Fibulacaris nereidis gen. et sp. nov., that will help us get closer to the truth.
Interpretive Cladogram |
The laterally compressed carapace covers most of the body. It is fused dorsally and merges anteriorly into a conspicuous postero-ventrally recurved rostrum as long as the carapace and positioned between a pair of backwards-facing pedunculate eyes.
The body is homonomous, with approximately 40 weakly sclerotized segments bearing biramous legs with elongate endopods, and ends in a pair of small flap-like caudal rami. Fibulacaris nereidis is interpreted as a suspension feeder possibly swimming inverted, in a potential case of convergence with some branchiopods.
A Bayesian phylogenetic analysis places it within a group closely related to the extinct Hymenocarina. Fibulacaris nereidis is unique in its carapace morphology and overall widens the ecological disparity of Cambrian arthropods and suggests that the evolution of a ‘bivalved' carapace and an upside-down lifestyle may have occurred early in stem-group crustaceans.
Fibulacaris nereidis contributes to the increasing morphological, functional, ecologic and taxonomic diversity of bivalved arthropods known from the Cambrian period. The shape of the carapace, with its single posteriorly directed ventral rostrum, appears to be morphologically unique not only among Cambrian and other fossil species but similarly rare across extant crustaceans or other arthropods. The carapace, including the rostrum, most probably had a protective role, but as in other extant arthropods, could have contributed to swimming performance and the creation of feeding currents.
F. nereidis may have moved through our ancient seas swimming in an inverted position — rare across arthropods and analogous to that observed in anostracans and some cladocerans. This highlight the importance of the carapace morphology in palaeo-ecological reconstructions and show that the arthropod carapace was already both a morphologically and functionally diverse character in the Cambrian period.
Bivalved Cambrian Arthropods / Alejandro Izquierdo-López |
Their phylogenetic analysis reveals a potential new group of mandibulate deposits and suspension feeders with homonomous legs and segments — some lacking certain mandibulate characters, such as antennae or mandibles — which may be related to an adaptation to this ecological niche and further illustrate a case of convergent evolution with some branchiopod taxa.
These results suggest that the bivalved carapace could have been a basal trait for all Mandibulata or may even have had an earlier origin if this and the bivalved carapace of the Isoxyiidae were found to be homologous.
Homologies between arthropod carapaces, bivalved or not, and structures such as radiodont shields, non-crustaceomorph univalved carapaces (e.g. Burgessia, Naraoia) and head shields (e.g. fuxianhuiids, habeliids, nauplius) are still quite poorly understood. We will need to find more examples to fully flesh out a comprehensive evolutionary analysis on this trait.
Besides, new data and morphological revisions on key bivalved arthropods could reshape the present phylogenetic analyses. Nonetheless, Cambrian bivalved arthropods certainly show a high ecological and taxonomic disparity, that is increasingly contributing to the understanding of the evolution of early arthropods and the Cambrian period as a whole.
Top Image by the talented Danielle Dufault @MesozoicMuse. Composite Bivalved Cambrian Arthropods by Alejandro Izquierdo-López.
Illustration: Interpretative cladogram based on a consensus tree from a Bayesian analysis using a Markov k model on a morphological dataset with 90 taxa and 213 characters. There is some interpretation here. Numbers next to nodes are posterior probabilities. The yellow box indicates the new monophyletic group to which Fibulacaris belongs. The green box highlights the group Hymenocarina.
Reference link: A Burgess Shale mandibulate arthropod with a pygidium: a case of convergent evolution. https://onlinelibrary.wiley.com/doi/abs/10.1002/spp2.1366
Wednesday, 23 June 2021
PAKUCARIS APATIS: A PAC-MAN-LIKE-CRAB OF THE GODDESS OF DECEIT
Pakucaris apatis. Illustration by Danielle Dufault, ROM |
In it, Alejandro Izquierdo-López and Jean-Bernard Caron untangle the evolutionary mysteries of Cambrian bivalved arthropods — a polyphyletic group of carapace-bearing arthropods that includes stem euarthropods, stem mandibulates and crustaceans.
They describe Pakucaris apatis gen. et sp. nov., a new stem mandibulate bivalved arthropod from the middle Cambrian, Wuliuan Stage, Burgess Shale at Marble Canyon, Kootenay National Park, British Columbia, Canada.
This new half a billion-year-old Burgess Shale mandibulate arthropod is the first we are seeing with a pygidium — an exciting case of convergent evolution.
In Pakucaris, the pygidium — the plate-like region formed by the fusion of posterior body segments — has limbs similar to the preceding thorax/trunk. In this case, it convergently evolved between trilobites, mollisoniids and Pakucaris apatis — though Kylinxia also had a pygidium.
Pakucaris apatis, a new Cambrian bivalved arthropod |
The authors note that the number of segments in the thorax and pygidium of Pakucaris apatis increase at the same rate.
If this occurs — as it does in trilobites — then the rate of segment generation in the pygidium must have exactly matched the rate of segment release.
In our new friend, Pakucaris apatis only a few specimens have ever been found, so we have only two morphotypes of this wee arthropod from 11.6–26.6 mm long, which differ mainly in their size and number of segments — possibly reflecting sexual dimorphism (the differences between male and female of a species) or different anamorphic stages.
Most specimens are around ~1 cm long but a single specimen is ~3 cm long. Given the limited number of specimens, we cannot yet speculate if we are seeing differences between males and females or post-embryonic growth and moulting stages within the species as seen in proturans and millipedes. Either possibility could be the case. We will hopefully find more of these lovelies within the Burgess Shale and elsewhere as a base of comparison.
Pakucaris apatis Alejandro Izquierdo @trichodes |
Around 20% of the posterior-most body segments and limbs are covered by a large spine-bearing shield. The head bears a pair of eyes, a possible pair of unsegmented appendicular projections and two pairs of segmented appendages.
The thorax is multisegmented, homonomous, with weakly sclerotized segments bearing biramous limbs, composed of a stenopodous endopod with c. 20 podomeres and a paddle-shaped exopod.
Pakucaris is interpreted as a nektobenthic suspension feeder. Bayesian phylogenetic analysis implies a position within Hymenocarina as stem mandibulates.
The posterior shield is regarded as a pygidium and represents a case of morphofunctional convergent evolution between mandibulates, artiopodans and mollisoniids.
Trilobite Anatomy for Comparison |
Many of our Cambrian arthropod friends faced similar living conditions and challenges — and adapted to them in similar means. Is this what we are seeing in Pakucaris? Maybe.
Pakucaris does have a rather fetching posterior shield, which may be analogous to a trilobite pygidium — the plate-like fused segments used for protection and sometimes enrolment. Arthropods have evolved this feature multiple times convergently. And many crustaceans technically go through a pygidium phase — the oddity there being retaining it into adulthood.
This study not only increases our understanding of the early evolution of mandibulates but also illustrates a unique case of early evolutionary convergence during the Cambrian Explosion.
The name Pakucaris apatis means Pac-Man-like crab of the goddess of deceit Apate. Maryam A., the collection managers at the Royal Ontario Museum suggested it after noting the resemblance to the videogame character. She was a huge contribution to the team pulling this paper together.
Bivalved Cambrian Arthropods / Alejandro Izquierdo |
Overall, Pakucaris shows us how different Cambrian bivalved arthropods can be — making our current phylogenies more difficult to clarify — and presents different features (frontal filaments, pygidium) which may be important as we look to understand early arthropod evolution.
Their paper was made possible by the University of Toronto and Royal Ontario Museum along with la Asociación de Becarios de la Caixa — funding research that expands our knowledge of nature. So far Pakucaris is classified in Hymenocarina — stem-crustaceans or mandibulates with bivalved carapaces — joining other Cambrian arthropods like Waptia fieldensis — but there is still much we do not know about this group and additional research — and research funding — will help us solve these mysteries.
Photos / Illustrations: Alejandro Izquierdo, University of Toronto. Art by Danielle Dufault, Palaeo-Scientific Ilustrator, Research Assistant at the Royal Ontario Museum, Host of Animalogic
References: A Burgess Shale mandibulate arthropod with a pygidium: a case of convergent evolution. https://onlinelibrary.wiley.com/doi/10.1002/spp2.1366
Tuesday, 22 June 2021
MEET ACICULOLENUS ASKEWI: A NEW UPPER CAMBRIAN TRILOBITE
The Dream Team at Fossil Site #15, East Kootenays, August 2, 2020 |
Chris New, pleased as punch atop Upper Cambrian Exposures |
Monday, 21 June 2021
GUT TRILOBITE: TAGMOSIS IN AGLASPIDID ARTHROPODS
Orygmaspis (Parabolinoides) contracta with gut structure |
And what is most exciting about this specimen is that there is clear preservation of some of the gut structures preserving this trilobite's last meal.
Documentation of non- or weakly biomineralizing animals that lived during the Furongian is essential for a comprehensive understanding of the diversification of metazoans during the early Palaeozoic.
Biomineralization, biologically controlled mineralization, occurs when crystal morphology, growth, composition, and location is completely controlled by the cellular processes of a specific organism. Examples include the shells of invertebrates, such as molluscs and brachiopods. The soft bits of those same animals tend to rot or be scavenged long before mineralization or fossilization can occur — hence, we find less of them.
So, not surprisingly, the fossil record of soft-bodied metazoans is particularly scarce for this critical time interval. To date, the fossils we do have are relatively rare and scattered at a dozen or so localities worldwide.
Location and stratigraphy of the Fossil Locality |
This specimen was found in Upper Cambrian exposures in the Clay Creek section at the top of the left fork of the ravine below Tanglefoot Mountain, 20 km northeast of Fort Steele.
It was the keen eyes of Chris Jenkins who noticed the interesting structures worthy of exploration.
Lerosey-Aubril along with colleagues, Patterson, Gibb and Chatterton, published a great study on this trilobite in Gondwana Research, February 2017.
Their work looked at this new occurrence of exceptional preservation in Furongian (Jiangshanian) strata of the McKay Group near Cranbrook, British Columbia, Canada. Their study followed up on the work of Chatterton et al. studying trilobites with phosphatised guts in this same 10-m-thick interval.
Lerosey-Aubril et al.'s paper looked at two stratigraphically higher horizons with soft-tissue preservation. One yielded a ctenophore and an aglaspidid arthropod, the other a trilobite with a phosphatised gut belonging to a different species than the previously described specimens.
Undetermined ctenophore |
The aglaspidid belongs to a new species of Glypharthrus, and is atypical in having twelve trunk tergites and an anteriorly narrow ‘tailspine’. These features suggest that the tailspine of aglaspidids evolved from the fusion of a twelfth trunk segment with the telson.
They also confirm the vicissicaudatan affinities of these extinct arthropods. Compositional analyses suggest that aglaspidid cuticle was essentially organic with a thin biomineralised (apatite) outer layer.
Macro imagery of the trilobite reveals previously unknown gut features — medial fusion of digestive glands — possibly related to enhanced capabilities for digestion, storage, or the assimilation of food.
These new fossils show that conditions conducive to soft-tissue preservation repeatedly developed in the outer shelf environment represented by the Furongian strata near Cranbrook. Future exploration of the c. 600-m-thick, mudstone-dominated upper part of the section is ongoing by Chris New, Chris Jenkins and Don Askey. There work and collaboration will likely result in more continued discoveries of exceptional fossils.
Glypharthrus magnoculus sp. |
Photo One: Orygmaspis (Parabolinoides) contracta (Trilobita) from the Jiangshanian (Furongian) part of the McKay Group, Clay Creek section, near Cranbrook, British Columbia, Canada. A–D, specimen RBCM.EH2016.031.0001.001, complete dorsal exoskeleton preserved dorsum-down and showing ventral features, such as the in situ hypostome and phosphatised digestive structures.
A, general view, specimen immersed under ethanol; B, detail of the digestive structures, specimen under ethanol; C, same as B, electron micrograph; D, same as B and C, interpretative drawing with digestive tract in blue-purple and digestive glands in pink.
Abbreviations: Dc 1 and 2, cephalic digestive glands 1 and 2, Dt1 and 5, thoracic digestive glands 1 and 5, hyp, hypostome, L2, glabellar lobe 2, LO, occipital lobe, T1 and 5, thoracic segments 1 and 5. Scale bars represent 2 mm (A) and 1 mm (B–D). For interpretation of the references to the colours in this figure legend, you'll want to read the full article in the link below.
Photo Two: Undetermined ctenophore from the Jiangshanian (Furongian) part of the McKay Group, Clay Creek section, near Cranbrook, British Columbia, Canada. A, B, specimen UA 14333, flattened body fragment with oral-aboral axis oriented parallel to bedding; specimen photographed immersed under dilute ethanol with presumed oral region facing to the bottom. A, general view. B, detailed view showing comb rows and ctene. Scale bars represent 1 cm (A) and 5 mm (B). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Photo Three: Glypharthrus magnoculus sp. nov. from the Jiangshanian (Furongian) part of the McKay Group, Clay Creek section, near Cranbrook, British Columbia, Canada. A–H, holotype, UA 14332, almost complete dorsal exoskeleton; photographs (A–C) and electron micrographs (D, backscattered; E–H, secondary) of the specimen in dorsal view with anterior facing to the top. A, B, general view in normal (A) and inverted (B) colours; C, D, detail of posterior trunk region, showing T12 and its contacts with T11 and the spiniform telson (arrows); the core of the fossil is made of a clay mineral and was initially entirely covered by an apatitic thin layer (white areas on D); E, left eye; F, right posterolateral glabellar lobe; G, rounded tubercles on right posterior border of cephalon; H, triangular tubercles pointing backwards (bottom right corner) on trunk axial region. Scale bars represent 5 mm (A, B), 1 mm (C, D), 500 μm (E, F), and 100 μm (G, H).
Link to the paper: https://www.researchgate.net/publication/309549546_Exceptionally-preserved_late_Cambrian_fossils_from_the_McKay_Group_British_Columbia_Canada_and_the_evolution_of_tagmosis_in_aglaspidid_arthropods