Thursday 4 June 2020

BASILEMYS FORELIMB

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

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

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

Wednesday 3 June 2020

BASILEMYS: FRESHWATER TURTLE

In April of 2018, Jordan Mallon and Donald Brinkman described a new species of nanhsiungchelyid turtle, Basilemys morrinensis, from a nearly complete shell from the Horsethief Member, lower Maastrichtian, Horseshoe Canyon Formation of Alberta.

You'll recall we've found Basilemys in the Sustut Basin of northern British Columbia. These two finds allow us to make some correlations on what was happening during the Upper Cretaceous in BC and Alberta.

The species Mallon and Brinkman wrote up is intermediate in age between the Campanian forms B. variolosa and B. gaffneyi and the upper Maastrichtian forms B. sinuosa and B. praeclara. It is also intermediate in its morphology, possessing a unique suite of both plesiomorphic — divided extragulars — and derived, square epiplastral beak, pygal wider than long, traits.

The Horseshoe Canyon specimen also boasts an autapomorphic square cervical scale. Phylogenetic analysis assuming parsimony recovers B. morrinensis in a polytomy with B. variolosa and B. gaffneyi, outside the clade formed by the upper Maastrichtian forms B. sinuosa and B. praeclara. The holotype of Basilemys morrinensis provides the first evidence that this genus reached a fairly large size, sometimes over a meter in length in the Horseshoe Canyon Formation, so not as small as previously thought based on less complete shell material.

Although Basilemys is usually regarded as terrestrial based on its skull and limb morphology, this specimen has a shell with a low profile — a derived hydrodynamic feature usually indicative of an aquatic mode of life.

The Horseshoe Canyon specimen was found with well-preserved fossils of Equisetum or horsetail. The Basilemys from Sustut was also found in association with plant fossils. So, aquatic, yes. But swampy freshwater aquatic. Or perhaps wet woods and the peripheries of water bodies — lakes, rivers, ponds. We know horsetails prefer a moist location and it appears our dear Basilymys did also. 

Image One: Basilemys morrinensis, CMN 57059, shell, in A, dorsal, B, ventral, C, right lateral, and D, anterior views. Photo: Donald B. Brinkman

Image Two: Depositional context of CMN 57059. Segmented stalks of Equisetum cf. E. perlaevigatum (marked by arrowheads) found associated with shell. B, CMN 57059 as it was originally uncovered in the field (CMN negative #61554). Scale bar equals 8 cm (A).  Photo: Donald B. Brinkman

Mallon, J. C., and D. B. Brinkman. 2018. Basilemys morrinensis, a new species of nanhsiungchelyid turtle from the Horseshoe Canyon Formation (Upper Cretaceous) of Alberta, Canada. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1431922.

Wednesday 27 May 2020

BOTTLENOSE DOLPHINS

These delightfully friendly and super smart fellows are Bottlenose dolphins. They are marine mammals who live in our world's oceans and breathe air at the surface, similar to humans.

They have lungs, inhaling and exhaling through a blowhole at the top of their heads instead of a through their nose.

Dolphins are social mammals and very playful. You may have seen them playing in the water, chasing boats or frolicking with one another. Humpback whales are fond of them and you'll sometimes see them hanging out together. They are also quite vocal, making a lot of interesting noises in the water. They squeak, squawk and use body language — leaping from the water while snapping their jaws and slapping their tails on the surface. They love to blow bubbles, will swim right up to you for a kiss and cuddle. Each individual dolphin has a signature sound, a whistle that is uniquely theirs. Dolphins use this whistle to tell one of their friends and family members from another.

Tuesday 26 May 2020

GRAY WHALES: ESCHRICHTIUS ROBUSTUS

Young Gray Whale, Eschrichtius robustus
The lovely fellow you see here is a young Gray Whale, Eschrichtius robustus, with a wee dusting of barnacles and his mouth ajar just enough to show his baleen.

Two Pacific Ocean populations are known to exist: one of about 200 individuals whose migratory route is presumed to be between the Sea of Okhotsk off Russia's south coast and southern Korea, and a larger one with a population of about 27,000 individuals in the eastern Pacific.

This second group are the ones we see off the shores of British Columbia as they travel the waters from northernmost Alaska down to Baja California. Gray whale mothers make this journey accompanied by their calves, hugging the shore in shallow kelp beds and providing rare but welcome glimpses of this beauty.

The gray whale is traditionally placed as the only living species in its genus and family, Eschrichtius and Eschrichtiidae, but an extinct species was discovered and placed in the genus in 2017 — the Akishima whale, E. akishimaensis. Some recent DNA analyses suggest that certain rorquals of the family Balaenopteridae, such as the humpback whale, Megaptera novaeangliae, and fin whale, Balaenoptera physalus, are more closely related to the gray whale than they are to some other rorquals, such as minke. Still, others place gray whales as outside the rorqual clade, a kissing cousin if you will.

John Edward Gray placed it in its own genus in 1865, naming it in honour of physician and zoologist Daniel Frederik Eschricht. The common name of the whale comes from its colouration. The subfossil remains of now-extinct gray whales from the Atlantic coasts of England and Sweden were used by Gray to make the first scientific description of a species then surviving only in Pacific waters. The living Pacific species was described by American palaeontologist, Edward Drinker Cope as Rhachianectes glaucus in 1869.

Fin Whale, Balaenoptera physalus
Skeletal comparisons showed the Pacific species to be identical to the Atlantic remains in the 1930s, and Gray's naming has been generally accepted since. Although identity between the Atlantic and Pacific populations cannot be proven by anatomical data, its skeleton is distinctive and easy to distinguish from that of all other living whales.

In 1993, a twenty-seven million-year-old specimen was discovered in deposits in Washington state that represents a new species of early baleen whale. It is especially interesting as it is from a stage in the group’s evolutionary history when baleen whales transitioned from having teeth to filtering food with baleen bristles.

Visiting researcher Carlos Mauricio Peredo studied the fossil whale remains, publishing his research to solidify Sitsqwayk cornishorum (pronounced sits-quake) in the annals of history. The earliest baleen whales clearly had teeth, and clearly still used them. Modern baleen whales have no teeth and have instead evolved baleen plates for filter feeding. Look to the rather good close-up of this young Gray Whale here to see his baleen where once there was a toothy grin.

The baleen is the comb-like strainer that sits on the upper jaw of baleen whales and is used to filter food. We have to ponder when this evolutionary change —moving from teeth to baleen — occurred and what factors might have caused it. Traditionally, we have sought answers about the evolution of baleen whales by turning to two extinct groups: the aetiocetids and the eomysticetids.

The aetiocetids are small baleen whales that still have teeth, but they are very small, and it remains uncertain whether or not they used their teeth. In contrast, the eomysticetids are about the size of an adult Minke Whale and seem to have been much more akin to modern baleen whales; though it’s not certain if they had baleen. Baleen typically does not preserve in the fossil record being soft tissue; generally, only hard tissue, bones and teeth are fossilized.

Sunday 24 May 2020

USING BARNACLES TO TRACK ANCIENT WHALES

We can trace the lineage of barnacles back to the Middle Cambrian. That's half a billion years of data to sift through. But if you divide that timeline in half yet again, we begin to understand barnacles and their relationship to other sea-dwelling creatures and their migration patterns.

It is through the study of fossil barnacles that are roughly 270,000 million years old that help track ancient whale migrations. University of California Berkeley doctoral student Larry Taylor, the lead author of the study, published March 25, 2019, in the peer-reviewed journal Proceedings of the National Academy of Sciences published on some clever findings. 

Taylor's research showed used fossil barnacles that hitched a ride on the backs of humpback and gray whales to reconstruct the migrations of whale populations millions of years ago.

The barnacles not only record details about the whales’ yearly travels but also retain this information after they become fossilized. By following this barnacle trail, Taylor et al. were able to reconstruct migration routes of whales from millions of years in the past.

Today, Humpback whales come from both the Southern Hemisphere (July to October with over 2,000 whales) and the Northern Hemisphere (December to March about 450 whales along Central America) to Panama (and Costa Rica). They undertake annual migrations from polar summer feeding grounds to winter calving and nursery grounds in subtropical and tropical coastal waters.

One surprise find is that the coast of Panama has been a meeting ground for humpback whales going back at least 270,000 years.

To see how the barnacles have travelled through the migration routes of ancient whales, the team used oxygen isotope ratios in barnacle shells and measured how they changed over time with ocean conditions. Did the whale migrate to warmer breeding grounds or colder feeding grounds? Barnacles retain this information even after they fall off the whale, sink to the ocean bottom, and become fossils. As a result, the travels of fossilized barnacles can serve as a proxy for the journeys of whales in the distant past.

Barnacles can play an important role in estimating paleo-water depths. The degree of disarticulation of fossils suggests the distance they have been transported, and since many species have narrow ranges of water depths, it can be assumed that the animals lived in shallow water and broke up as they were washed down-slope. The completeness of fossils, and nature of the damage, can thus be used to constrain the tectonic history of regions.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, barnacles are known as k̕wit̕a̱'a and broken barnacle shells are known as t̕sut̕su'ma.

Friday 22 May 2020

MANATEES AND DUGONGS

I had always grouped the dugongs and manatees together. There are slight differences between these two groups. Both groups belong to the order Sirenia.

They shared a cousin in the Steller's sea cow, Hydrodamalis gigas, but that piece of their lineage was hunted to extinction by our species in the 18th century. Dugongs have tail flukes with pointed tips and manatees have paddle-shaped tails, similar to a Canadian Beaver.

Both of these lovelies from the order Sirenia went from terrestrial to marine, taking to the water in search of more prosperous pastures, as it were. They are the extant and extinct forms of the oddball manatees and dugongs.

We find dugongs today in waters near northern Australia and parts of the Indian and Pacific Oceans. They inhabit rivers and shallow coastal waters, making the best use of their fusiform bodies that lack dorsal fins and hind limbs. I have been thinking about them in the context of some of the primitive armoured fish we find in the Chengjiang biota of China, specifically those primitive species that were also fusiform.

They favour locations where seagrass, their food of choice, grows plentiful and they eat it roots and all. While seagrass low in fibre, high in nitrogen, and easily digestible is preferred, dugongs will also dine on lower grade seagrass, algae, and invertebrates should the opportunity arise. They've been known to eat jellyfish, sea squirts, and shellfish over the course of their long lives. Some of the oldest dugongs have been known to live 70+ years, which is another statistic I find surprising. They are large, passive, have poor eyesight, and look pretty tasty floating in the water; a defenceless floating buffet. Their population is in decline and yet they live on.

Wednesday 20 May 2020

ANTHOZOA: CORALS

Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically live in compact colonies of many identical individual polyps.

Corals are important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.

A coral "group" is a colony of a myriad of genetically identical polyps. Each polyp is a sac-like animal typically only a few millimetres in diameter and a few centimetres in length. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which when mature settles to form a new colony.

Although some corals are able to catch plankton and small fish using stinging cells on their tentacles, most corals obtain the majority of their energy and nutrients from photosynthetic unicellular dinoflagellates of the genus Symbiodinium that live within their tissues. These are commonly known as zooxanthellae and gives the coral colour. Such corals require sunlight and grow in clear, shallow water, typically at depths less than 60 metres (200 ft). Corals are major contributors to the physical structure of the coral reefs that develop in tropical and subtropical waters, such as the Great Barrier Reef off the coast of Australia. These corals are increasingly at risk of bleaching events where polyps expel the zooxanthellae in response to stress such as high water temperature or toxins.

Other corals do not rely on zooxanthellae and can live globally in much deeper water, such as the cold-water genus Lophelia which can survive as deep as 3,300 metres (10,800 ft). Some have been found as far north as the Darwin Mounds, northwest of Cape Wrath, Scotland, and others off the coast of Washington State and the Aleutian Islands.

Tuesday 19 May 2020

CANGREJO FÓSIL: COSTACOPLUMA

If you take a peek at this well-preserved fossilized crab, you can see the back section of his carapace composed of highly mineralized chitin.

Chitin is a polysaccharide — a large molecule made of many smaller monosaccharides or simple sugars, like glucose. It's handy stuff, forming crystalline nanofibrils or whiskers.

Chitin is actually the second most abundant polysaccharide after cellulose. It's interesting as we usually think of these molecules in the context of their sugary context but they build many other very useful things in nature — not the least of these are the hard outer shells or exoskeletons of our crustacean friends. There have been some wonderful studies published of late on the cuticular structure of crabs and in particular the Late Maastrichtian crab, Costacopluma mexicana, from deposits near the town of from near Paredón, Ramos Arizpe in what is now southern Coahuila (formerly Coahuila de Zaragoza), in north-eastern Mexico. We see this same species in the Upper Cretaceous Moyenne of Northeast Morocco and from the Pacific slope, Paleocene of California, USA. This beauty is in the collection of José F. Ventura‎.

While the crustacean cuticle has been the subject of study for over 250 years (Reaumur, 1712, in Drach, 1939), the focus of that early work has been the process of moulting. Because crabs and other crustaceans have a hard outer shell (the exoskeleton) that does not grow, they must shed their shells through a process called moulting. Just as we outgrow our shoes, crabs outgrow their shells.

In 1984, Roer and Dillaman took a whole new approach, instead looking at the exoskeleton as a mineralized tissue. The integument of decapod crustaceans consists of an outer epicuticle, an exocuticle, an endocuticle and an inner membranous layer underlain by the hypodermis. The outer three layers of the cuticle are calcified.

The mineral is in the form of calcite crystals and amorphous calcium carbonate. In the epicuticle, the mineral is in the form of spherulitic calcite islands surrounded by the lipid-protein matrix. In the exo- and endo-cuticles the calcite crystal aggregates are interspersed with chitin-protein fibres which are organized in lamellae. In some species, the organization of the mineral mirrors that of the organic fibres, but such is not the case in certain cuticular regions in the xanthid crabs.

Control of crystal organization is a complex phenomenon unrelated to the gross morphology of the matrix. Since the cuticle is periodically moulted to allow for growth, this necessitates a bidirectional movement of calcium into the cuticle during post-moult and out during premolt resorption of the cuticle.

These movements are accomplished by active transport affected by a Ca-ATPase and Na/Ca exchange mechanism. The epi- and exo-cuticular layers of the new cuticle are elaborated during pre-moult but do not calcify until the old cuticle is shed. This phenomenon also occurs in vitro in the cuticle devoid of living tissue and implies an alteration of the nucleating sites of the cuticle in the course of the moult.

We're still learning about the relationship between the mineral and the organic components of the cuticle, both regarding the determination of crystal morphology and about nucleation. While the Portunidae offers some knowledge of the mechanisms and pathways for calcium movement, we know nothing concerning the transport of carbonate. These latter areas of investigation will prove fertile ground for future work; work which will provide information not only on the physiology of Crustacea but also on the basic principles of mineralization. I'm interested to see what insights will be revealed in the years to come. Certainly, the bidirectional nature of mineral transport and the sharp temporal transitions in the nucleating ability of the cuticular matrix provide ideal systems in which to study these aspects of calcification.

Torrey Nyborg, Francisco J. Vega and Harry F. Filkorn, Boletín de la Sociedad Geológica Mexicana, Vol. 61, No. 2, Número especial XI Congreso Nacional de Paleontología, Juriquilla 2009 (2009), pp. 203-209. Coahuila paleo coordinates:25°32′26″N 100°57′2″W

Monday 18 May 2020

CRABS AND CHITIN

Crabs are decapod crustaceans of the Phyllum Arthopoda. They inhabit all the world's oceans, many of our freshwater lakes and streams, and a call a few places on land home.

Crabs build their shells from highly mineralized chitin. Chitin gets around. It is the main structural component of the exoskeletons of many of our crustacean and insect friends. Shrimp, crab, and lobster all use it to build their exoskeletons.

Chitin is a polysaccharide — a large molecule made of many smaller monosaccharides or simple sugars, like glucose. It's handy stuff, forming crystalline nanofibrils or whiskers. Chitin is actually the second most abundant polysaccharide after cellulose. It's interesting as we usually think of these molecules in the context of their sugary context but they build many other very useful things in nature — not the least of these are the hard shells or exoskeletons of our crustacean friends.

Sunday 17 May 2020

PROTOEASTER NODOSUS

If you happen to be swimming in the warm, shallow waters of the Indo-Pacific region, you may encounter one of the most charming of all the sea stars, Protoeaster nodosus.

These beauties are commonly known as Horned Sea Stars or, my personal favorite, Chocolate Chip Sea Stars.

They are part of the class Asteroidea (starfish or sea stars) one of the most diverse groups within the phylum Echinodermata and have a lengthy lineage in the fossil record stretching all the way back to the Triassic. These echinoderms make a living on near-shore sandy bottoms or lurk in the seagrass meadows of some of our most beautiful waters.

Chocolate Chip Sea Stars live in the waters off the Philippine Sea, off the coast of Australia and New Guinea. Their range extends to the Marshall Islands through central and southeastern Polynesia, past Easter Island and all the way up to Hawaii. Pretty much pick any of the top contenders for a warm, tropical vacation and they've beaten you to it!

This species of sea star has black rows of "horns" or "spines" meant to scare off predators. A noble deterrent for his fishy friends but I find this signature decoration rather fetching. These fellows like to graze on choice corals and sponges. They are also happy to make a meal of snails and bitter sea urchins when these ambrosial treats are presented. And they are social, both to mate, gathering in groups to aid in fertilization and acting as a softcover for shrimp, wee brittle stars and juvenile leatherjackets or filefish, who tuck in and enjoy the protective cover of those dark nodes.

Friday 15 May 2020

SOUTH AMERICAN TAPIR

South American Tapir, Tapirus terrestris
This little sweetie with his brown fur stripped and dotted with bits of white is a South American tapir, Tapirus terrestris.

He's a water baby and a relative of the rhinoceros. Tapir love the water. They play, swim, dive, and use it to protect themselves from predators.

Their feet are specially designed for swimming and walking on muddy shores. Each of their front feet has four splayed toes, a bit like having a fin or snowshoe on your feet. Their back feet have a similar design but with three toes. They nap and hide in the forest during the day and then head out at night to munch on leaves, shoots, fruit, and other green goodies in the Amazon Rainforest and the River Basin in South America, east of the Andes.

They can be found in Venezuela, Colombia, and the Guianas in the north to Brazil, Argentina, and Paraguay in the south, to Bolivia, Peru, and Ecuador in the west. Three species of Tapir call Columbia home and much of the scientific research is focussed on this area. They're also hiring if you'd like to get more involved. While many find them adorable, sadly, they are also appreciated for their beautiful coats. Their dwindling numbers are largely due to poaching for their meat and hide, as well as habitat destruction. If I had the means, I'd buy up a big chunk of land where they could roam free. Some folks are helping and you can, too. There is a Tapir Preservation Fund set-up to aid these cuties with additional habitat. I'll pop the link here so you can check them out. They have a Facebook page and on it, there is the sweetest video of a Tapir sitting in the waves watching the sunset. Do check it out. It's very sweet.

Tapir Specialist Group: https://tapirs.org/conservation/tsgcf/
TSG Brazil: Rua Lindóia, 79046-150 Campo Grande, Brazil / +55 67 3344-0240

Thursday 14 May 2020

DRIFTWOOD CANYON: FOSSIL TAPIRS, HEDGEHOGS, BIRDS & FLOWERS

Early Eocene Tapir from Driftwood Canyon
Driftwood Canyon in British Columbia is known for its beautiful early Eocene plants. It's not surprising to find wonderful wee mammals making a living in this warm, wet, steamy rainforest setting 51 million years ago.

Today, Driftwood Provincial Park is about halfway between Prince George and Prince Rupert near the town of Smithers. The rocks that make up the strata here started out further to the south, riding geologic plates to their current location.

Along with the Tapir and a rather sweet hedgehog, we also find birds, insects, and a huge variety of fossil plants in these outcrops. Fossils of plant remains are rare but include up to 29 genera. The most common plant fossils found are leafy shoots of the dawn redwood, Metasequoia, and the floating fern Azolla primaeva as mats of plants or as isolated fossils.

Fossil fish from Driftwood Canyon in the Canadian Museum of Nature includes specimens collected in the 1930s; however, Driftwood Canyon fossils have only been studied since the 1950s.

The Driftwood Canyon fossil beds are best known for the abundant and well-preserved insect and fish fossils (Amia, Amyzon, and Eosalmo). The insects are particularly diverse and well preserved and include water striders (Gerridae), aphids (Aphididae), leafhoppers (Cicadellidae), green lacewings (Neuroptera), spittlebugs (Cercopidae), march flies (Bibionidae), scorpionflies (Mecoptera), fungus gnats (Mycetophilidae), snout beetles (Curculionidae), and ichneumon wasps.

A fossil species of green lacewing (Neuroptera, Chrysopidae) was recently named Pseudochrysopa harveyi to honour the founder of the park, Gordon Harvey. Fossil feathers are sometimes found and rare rodent bones are sometimes found in fish coprolites. Most recently, fossil palm beetles (Bruchidae) were described from the beds, confirming the presence of palms (Arecaceae) in the local environment in the early Eocene.

Alder, Alnus sp., still common today are also found, as well as the leaves or needles and seeds of pines, Pinus sp., the golden larch, Pseudolarix sp., cedars, Chamaecyparis and/or Thuja spp., redwood Sequoia sp., and rare Ginkgo and sassafras, Sassafras hesperia, leaves. A lovely permineralized pine cone Pinus driftwoodensis and associated 2-needle foliage were described from the site in the 1980s.

Rare flowers and the seeds of flowering plants have been collected, including Ulmus, Florissantia, and Dipteronia, a genus of trees related to maples, Acer. spp., that today grows in eastern Asia.

If you fancy a trip to Driftwood Canyon Provincial Park, follow Driftwood Road from Provincial Highway 16. A car park just off the road access leads to an interpretive sign and a bridge across Driftwood Creek. A short interpretive trail leads visitors to a cliff-face exposure of Eocene shales. Signate speaks to how these beds were deposited in an inter-montane lake. Interbedded within the shales are volcanic ash beds, the result of area volcanoes that were erupting throughout the life of the Eocene lake that produced the shales.

Wednesday 13 May 2020

WOLVERINE RIVER DINOSAUR TRACKS

Jen Becker, British Columbia Paleontological Alliance Field Trip
In the summer of 2005, I joined Jen Becker, and fellow delegates from the British Columbia Paleontological Symposium for an impromptu late-night tour of Wolverine River, one of many prolific research sites of Lisa Buckley, a vertebrate paleontologist working in the Tumbler Ridge area of British Columbia.

There are two types of footprints at the Wolverine River Trackside –theropods (at least four different sizes) and ankylosaurs. The prints featured in this photo were laid down by some lumbering ankylosaurs out for a stroll in soft mud. Many of the prints are so shallow that they can only be recognized by the skin impressions pressed into the mud. We'd been up to the fossil sites in the day but wanted to come back in the evening to see them by lamplight. After a lovely dinner, we hiked up to Wolverine in the dark. We filled the tracks with water and lit them with warm yellow lamplight. Some clever soul brought a sound system and played spooky animal calls to add prehistoric ambiance. A truly amazing evening.

Tuesday 12 May 2020

DARWIN AND THE GREAT DEBATE

Oxford University Museum of Natural History was established in 1860 to draw together scientific studies from across the University of Oxford.

On 30 June 1860, the Museum hosted a clash of ideologies that has become known as the Great Debate.

Even before the collections were fully installed, or the architectural decorations completed, the British Association for the Advancement of Science held its 30th annual meeting to mark the opening of the building, then known as the University Museum. 

It was at this event that Samuel Wilberforce, Bishop of Oxford, and Thomas Huxley, a biologist from London, went head-to-head in a debate about one of the most controversial ideas of the 19th century – Charles Darwin's theory of evolution by natural selection.

Notable collections include the world's first described dinosaur,  Megalosaurus bucklandii, and the world-famous Oxford Dodo, the only soft tissue remains of the extinct dodo. Although fossils from other areas have been assigned to the genus, the only certain remains of Megalosaurus come from Oxfordshire and date to the late Middle Jurassic. 

In 1824, Megalosaurus was the first genus of non-avian dinosaur to be validly named. The type species is Megalosaurus bucklandii, named in 1827.

In 1842, Megalosaurus was one of three genera on which Richard Owen based his Dinosauria. On Owen's direction, a model was made as one of the Crystal Palace Dinosaurs, which greatly increased the public interest for prehistoric reptiles. 

Subsequently, over fifty other species would be classified under the genus, originally because dinosaurs were not well known, but even during the 20th century after many dinosaurs had been discovered. 

Today it is understood these additional species were not directly related to M. bucklandii, which is the only true Megalosaurus species. Because a complete skeleton of it has never been found, much is still unclear about its build.

The Museum is as spectacular today as when it opened in 1860. As a striking example of Victorian neo-Gothic architecture, the building's style was strongly influenced by the ideas of 19th-century art critic John Ruskin. Ruskin believed that architecture should be shaped by the energies of the natural world, and thanks to his connections with a number of eminent Pre-Raphaelite artists, the Museum's design and decoration now stand as a prime example of the Pre-Raphaelite vision of science and art.

Sunday 10 May 2020

CRETACEOUS HADROSAUR FROM ALBERTA

A rare and very beautifully preserved Cretaceous Hadrosaur Tooth. This lovely specimen is from one of our beloved herbivorous "Duck-Billed" dinosaurs from 68 million-year-old outcrops near Drumheller, Alberta, Canada, and is likely from an Edmontosaurus.

When you scour the badlands of southern Alberta, most of the dinosaur material you'll find are from hadrosaurs. These lovely tree-less valleys make for excellent-searching grounds and have led us to know more about hadrosaur anatomy, evolution, and paleobiology than for most other dinosaurs.

We have oodles of very tasty specimens and data to work with. We've got great skin impressions and scale patterns from at least ten species and interesting pathological specimens that provide valuable insights into hadrosaur behaviour. Locally, we have an excellent specimen you can visit in the Courtenay and District Museum on Vancouver Island, Canada. The first hadrosaur bones were found on Vancouver Island a few years back by Mike Trask, VIPS, on the Trent River near Courtenay.

The Courtenay hadrosaur is a first in British Columbia, but our sister province of Alberta has them en masse. Given the ideal collecting grounds, many of the papers on hadrosaurs focus on our Canadian finds. These herbivorous beauties are also found in Europe, South America, Mexico, Mongolia, China, and Russia. Hadrosaurs had teeth arranged in stacks designed for grinding and crushing, similar to how you might picture a cow munching away on the grass in a field. These complex rows of "dental batteries" contained up to 300 individual teeth in each jaw ramus. But even with this great number, we rarely see them as individual specimens.

They didn't appear to shed them all that often. Older teeth that are normally shed in our general understanding of vertebrate dentition, were resorped, meaning that their wee osteoclasts broke down the tooth tissue and reabsorbed the yummy minerals and calcium.

As the deeply awesome Mike Boyd notes, "this is an especially lucky find as hadrosaurs did not normally shed so much as a tooth, except as the result of an accident when feeding or after death. Typically, these fascinating dinosaurs ground away their teeth... almost to nothing."

In hadrosaurs, the root of the tooth formed part of the grinding surface as opposed to a crown covering over the core of the tooth. And curiously, they developed this dental arrangement from their embryonic state, through to hatchling then full adult.

There's some great research being done by Aaron LeBlanc, Robert R. Reisz, David C. Evans and Alida M. Bailleul. They published in BMC Evolutionary Biology on work that looks at the histology of hadrosaurid teeth analyzing them through cross-sections. Jon Tennant did a nice summary of their research. I've included both a link to the original journal article and Jon Tennant's blog below.

LeBlanc et al. are one of the first teams to look at the development of the tissues making up hadrosaur teeth, analyzing the tissue and growth series (like rings of a tree) to see just how these complex tooth batteries formed.

They undertook the first comprehensive, tissue-level study of dental ontogeny in hadrosaurids using several intact maxillary and dentary batteries and compared them to sections of other archosaurs and mammals. They used these comparisons to pinpoint shifts in the ancestral reptilian pattern of tooth ontogeny that allowed hadrosaurids to form complex dental batteries.

References:

LeBlanc et al. (2016) Ontogeny reveals function and evolution of the hadrosaurid dinosaur dental battery, BMC Evolutionary Biology. 16:152, DOI 10.1186/s12862-016-0721-1 (OA link)

To read more from Jon Tennant, visit: https://blogs.plos.org/paleocomm/2016/09/14/all-the-better-to-chew-you-with-my-dear/

Photo credit: Derrick Kersey. For more awesome fossil photos like this from Derrick, visit his page: https://www.facebook.com/prehistoricexpedition/

Thursday 7 May 2020

ANCIENT SWAMPS AND SOLAR FLARES

If fossil fuels are made from fossils, are oil, gas and coal made from dead dinosaurs? Well, no, but they are made from fossils. We do not heat our homes or run our cars on dead hadrosaurs. Instead, we burn very old plants and algae. 

It sounds much less exciting, but the process by which algae and other plant life soak up the Sun's energy, store it for millions of years, then give it all up for us to burn as fuel is a pretty fantastic tale.

Fossil fuel is formed by a natural process — the anaerobic decomposition of buried dead organisms. These plants and algae lived and died many millions of years ago, but while they lived, they soaked up and stored energy from the sun through photosynthesis. Picture ancient trees, algae and peat soaking up the sun, then storing that energy for us to use millions of years later. These organisms and their resulting fossil fuels are millions of years old, sometimes more than 650 million years. That's way back in the day when Earth's inhabitants were mostly viruses, bacteria and some early multi-cellular jelly-like critters.

Fossil fuels consist mainly of dead plants – coal from trees, and natural gas and oil from algae, a diverse group of aquatic photosynthetic eukaryotic organisms I like to think of as pond scum. These deposits are called fossil fuels because, like fossils, they are the remains of plants and animals that lived long ago.

If we could go back far enough, we'd find that our oil, gas, and coal deposits are really remnants of algal pools, peat bogs and ancient muddy swamps. Dead plants and algae accumulate and over time, the pressure turns the mud mixed with dead plants into rock. Geologists call the once-living matter in the rock kerogen. If they haven't been cooked too badly, we call them fossils.

Kerogen is the solid, insoluble organic matter in sedimentary rocks and it is made from a mixture of ancient organic matter. A bit of this tree and that algae all mixed together to form a black, sticky, oily rock. The Earth’s internal heat cooks the kerogen. The hotter it gets, the faster it becomes oil, gas, or coal. If the heat continues after the oil is formed, all the oil turns to gas. The oil and gas then seep through cracks in the rocks. Much of it is lost. We find oil and gas today because some happened to become trapped in porous, sponge-like rock layers capped by non-porous rocks. We tap into these the way you might crack into a bottle of olive oil sealed with wax.

Fossil fuel experts call this arrangement a reservoir and places like Alberta, Iran and Qatar are full of them. A petroleum reservoir or oil and gas reservoir is a subsurface pool of hydrocarbons contained in porous or fractured rock formations. Petroleum reservoirs are broadly classified as conventional and unconventional reservoirs. In the case of conventional reservoirs, the naturally occurring hydrocarbons, such as crude oil or natural gas, are trapped by overlying rock formations with lower permeability. In unconventional reservoirs, the rocks have high porosity and low permeability which keeps the hydrocarbons trapped in place, so these unconventional reservoirs don't need a rock cap.

Coal is an important form of fossil fuel. Much of the early geologic mapping of Canada — and other countries — was done for the sole purpose of mapping the coal seams. You can use it to heat your home, run a coal engine or sell it for cold hard cash. It's a dirty fuel, but for a very long time, most of our industries used it as the sole means of energy. But what is so bad about burning coal and other fossil fuels? Well, many things...

Burning fossil fuels, like oil and coal, releases large amounts of carbon dioxide and other gases into the atmosphere. They get trapped as heat, which we call the greenhouse effect. This plays havoc with global weather patterns and our world does not do so well when that happens. 

The massive end-Permian extinction event, the worst natural disaster in Earth's history — when 90% of all life on Earth died —  was caused by massive volcanic eruptions that spewed gas and lava, covering the Earth in volcanic dust, then acid rain. Picture Mordor times ten. This wasn't a culling of the herd, this was full-on decimation. I'll spare you the details, but the whole thing ended poorly.

Dirty or no, coal is still pretty cool. It is wild to think that a lump of coal has the same number of atoms in it as the algae or material that formed it millions of years ago. Yep, all the same atoms, just heated and pressurized over time. When you burn a lump of coal, the same number of atoms are released when those atoms dissipate as particles of soot. You may wonder what makes a rock burn. It's not intuitive that it would be possible, and yet there it is. Coal is combustible, meaning it is able to catch fire and burn. Coal is made up mostly from carbon with some hydrogen, sulphur — which smells like rotting eggs — oxygen and nitrogen thrown in.

It is just that the long-ago rain forest was far less dense than the coal you hold in your hand today, and so is the soot into which it dissipates once burned. The energy was captured by the algal pool or rain forest by way of photosynthesis, then that same energy is released when the coal is burnt. So the energy captured in gravity and released billions of years later when the intrinsic gravity of the coal is dissipated by burning. It's enough to bend your brain.

The Sun loses mass all the time because of its process of fusion of atomic content and radiating that energy as light. Our ancient rain forests and algal pools on Earth captured some of it. So maybe our energy transformations between the Earth and the Sun could be seen more like ping-pong matches, with energy, as the ball, passing back and forth.

As mass sucks light in (hello, photosynthesis), it becomes denser, and as mass radiates light out (hello, heat from coal), it becomes less dense. Ying, yang and the beat goes on.

Wednesday 6 May 2020

ZENASPIS PODOLICA OF THE UKRAINE

A Devonian bony fish mortality plate showing a lower shield of Zenaspis podolica (Lankester, 1869) from Lower Devonian deposits of Podolia, Ukraine.

Podolia or Podilia is a historic region in Eastern Europe, located in the west-central and south-western parts of Ukraine, in northeastern Moldova. Podolia is the only region in Ukraine where 420 million-year-old remains of ichthyofauna can be found near the surface, making them accessible to collection and study. Zenaspis is an extinct genus of jawless fish which thrived during the early Devonian. Being jawless, Zenaspis was probably a bottom feeder, snicking on debris from the seafloor similar to how flounder, groupers, bass and other bottom-feeding fish make a living.

For the past 150 years, vertebrate fossils have been found in more than 90 localities situated in outcrops along banks of the Dniester River and its northern tributaries, and in sandstone quarries. At present, the faunal list of Early Devonian agnathans and fishes from Podolia number seventy-two species, including 8 Thelodonti, 39 Heterostraci, 19 Osteostraci, 4 Placodermi, 1 Acanthodii, and 1 Holocephali (Voichyshyn 2001a).

In Podolia, the Lower Devonian Redbeds strata (the Old Red Formation or Dniester Series) are 1800 metres thick and range from Lochkovian to Eifelian in age (Narbutas 1984; Drygant 2000, 2003).

In their lower part, the Ustechko and Khmeleva members of the Dniester Series, they consist of lovely multicoloured, mainly red, fine-grained cross-bedded massive quartz sandstones and siltstones with seams of argillites (Drygant 2000).

We see fossils of Zenaspis in the early Devonian of Western Europe. Both Zenaspis pagei and Zenaspis poweri can be found up to 25 centimetres long in Devonian outcrops of Scotland.

Reference: Voichyshyn, V. 2006. New osteostracans from the Lower Devonian terrigenous deposits of Podolia, Ukraine. Acta Palaeontologica Polonica 51 (1): 131–142. Photo care of the awesome Fossilero Fisherman.

Tuesday 5 May 2020

CARCHARODON MEGALODON CHUBUTENSIS

Carcharocles chubutensis, which roughly translates to the "glorious shark of Chubut," from the ancient Greek is an extinct species of prehistoric mega-toothed sharks in the genus Carcharocles.

These big beasties lived during Oligocene to Miocene. This fellow is considered to be a close relative of the famous prehistoric mega-toothed shark, C. megalodon, although the classification of this species is still disputed.

Swiss naturalist Louis Agassiz first identified this shark as a species of Carcharodon in 1843. In 1906, Ameghino renamed this shark as C. chubutensis. In 1964, shark researcher, L. S. Glikman recognized the transition of Otodus obliquus to C. auriculatus. In 1987, shark researcher, H. Cappetta reorganized the C. auriculatus - C. megalodon lineage and placed all related mega-toothed sharks along with this species in the genus Carcharocles.

At long last, the complete Otodus obliquus to C. megalodon progression began to look clear. Since then, C. chubutensis has been re-named into Otodus chubutensis, also the other chronospecies of the Otodus obliquus - O. megalodon lineage. Chubutensis appears at the frontier Upper Oligocene to Lowest Miocene (evolving from O. angustidens which has stronger side cusps) and turns into O. megalodon in the Lower to Middle Miocene, where the side cusps are already absent. Despite previous publications, there is no chubutensis in the Pliocene.

Victor Perez and his team published on the transition between Carcharocles chubutensis and Carcharocles megalodon (Otodontidae, Chondrichthyes): lateral cusplet loss through time in March of 2018. In their work, they look at the separation between all the teeth of Carcharocles chubutensis and Carcharocles megalodon and published that it is next to impossible to divide them up as a complex mosaic evolutionary continuum characterizes this transformation, particularly in the loss of lateral cusplets.

A modern shark after a tasty snack
The cuspleted and uncuspleted teeth of Carcharocles spp. are designated as chronomorphs because there is wide overlap between them both morphologically and chronologically.

In the lower Miocene Beds (Shattuck Zones) 2–9 of the Calvert Formation (representing approximately 3.2 million years, 20.2–17 Ma, Burdigalian) both cuspleted and uncuspleted teeth are present, but cuspleted teeth predominate, constituting approximately 87% of the Carcharocles spp. teeth represented in their samples.

In the middle Miocene Beds 10–16A of the Calvert Formation (representing approximately 2.4 million years, 16.4–14 Ma, Langhian), there is a steady increase in the proportion of uncuspleted Carcharocles teeth.

In the upper Miocene Beds 21–24 of the St. Marys Formation (approx. 2.8 million years, 10.4–7.6 Ma, Tortonian), lateral cusplets are nearly absent in Carcharocles teeth from our study area, with only a single specimen bearing lateral cusplets. The dental transition between Carcharocles chubutensis and Carcharocles megalodon occurs within the Miocene Chesapeake Group. Although their study helps to elucidate the timing of lateral cusplet loss in Carcharocles locally, the rationale for this prolonged evolutionary transition remains unclear.

The specimen you see here is in the Geological Museum in Lisbon. The photo credit goes to the deeply awesome Luis Lima who shared some wonderful photos of his recent visit to their collections.
If you'd like to read the paper from Perez, you can find it here:
https://www.tandfonline.com/doi/full/10.1080/02724634.2018.1546732

Monday 4 May 2020

SOLAR WINDS: THE MAGNETOSPHERE

The Earth has a magnetic field with north and south poles. The magnetic field of the Earth is surrounded by the magnetosphere that keeps most of the particles from the Sun from hitting the Earth.

Some of these particles from the solar wind enter the atmosphere at one million miles per hour. We see them as one of the most beautiful of all natural phenomena -- Earth's polar lights, the aurora borealis in the north and the aurora australis, near the south pole.

The auroras occur when highly charged electrons from the solar wind interact with elements in the Earth's atmosphere and become trapped in the Earth's magnetic field.

We see them as an undulating visual field of red, yellow, green, blue and purple dancing high in the Earth's atmosphere -- about 100 to 400 kilometers above us. This image shows the parts of the magnetosphere. 1. Bow shock. 2. Magnetosheath. 3. Magnetopause. 4. Magnetosphere. 5. Northern tail lobe. 6. Southern tail lobe. 7. Plasmasphere.

Photo credit: Magnetosphere_Levels.jpg: Dennis Gallagherderivative work: Frédéric MICHEL - Magnetosphere_Levels.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=9608059

Sunday 3 May 2020

SUNLIGHT & OUR SOLAR SYSTEM

Solar flares, sunlight, what are they actually? Yes, it's light from the Sun but so much more than that. Sunlight is both light and energy. Once it reaches Earth, we call this energy, "insolation," a fancy term for solar radiation. The amount of energy the Sun gives off changes over time in a never-ending cycle.

Solar flares (hotter) and sunspots (cooler) on the Sun's surface impact the amount of radiation headed to Earth. These periods of extra heat or extra cold (well, cold by Sun standards...) can last for weeks, sometimes months.

The beams that reach us and warm our skin are electromagnetic waves that bring with them heat and radiation, by-products of the nuclear fusion happening as hydrogen nuclei fuse and shift violently to form helium, a process that fires every star in the sky. Our bodies convert the ultraviolet rays to Vitamin D. Plants use the rays for photosynthesis, a process of converting carbon dioxide to sugar and using it to power their growth (and clean our atmosphere!) That process looks something like this: carbon dioxide + water + light energy — and glucose + oxygen = 6 CO2(g) + 6 H2O + photons → C6H12O6(aq) + 6 O2(g).

Photosynthetic organisms convert about 100–115 thousand million metric tonnes of carbon to biomass each year, about six times more power than used us mighty homo sapien sapiens. Our plants, forests and algae soak up this goodness and much later in time, we harvest this energy from fossil fuels.

We've yet to truly get a handle on the duality between light as waves and light as photons. The duality of the two-in-oneness of light; of their waves and alter-ego, particle photons is a physicists delight. Einstein formulated his special theory of relativity in part by thinking about what it would be like to ride around on these waves. What would space look and feel like? How would time occur? It bends the mind to consider. His wave-particle view helped us to understand that these seemingly different forms change when measured. To put this in plain English, they change when viewed, ie. you look them "in the eye" and they behave as you see them.

Light fills not just our wee bit of the Universe but the cosmos as well, bathing it in the form of cosmic background radiation that is the signature of the Big Bang and the many mini-big bangs of supernovae as they go through cycles of reincarnation and cataclysmic death — exploding outward and shining brighter than a billion stars.

In our solar system, once those electromagnetic waves leave the Sun headed for Earth, they reach us in a surprising eight minutes. We experience them as light mixed with the prism of beautiful colours. But what we see is actually a trick of the light. As rays of white sunlight travel through the atmosphere they collide with airborne particles and water droplets causing the rays to scatter.

We see mostly the yellow, orange and red hues (the longer wavelengths) as the blues and greens (the shorter wavelengths) scatter more easily and get bounced out of the game rather early.

Saturday 2 May 2020

NEUTRINOS AND DARK MATTER

Deep inside the largest and deepest gold mine in North America scientists are looking for dark matter particles and neutrinos instead of precious metals. It may not seem exciting on the surface — but it was far below!

The Homestake Gold Mine in Lawrence County, South Dakota was a going concern from about 1876 to 2001.

The mine produced more than forty million troy ounces of gold in its one hundred and twenty-five-year history, dating back to the beginnings of the Black Hills Gold Rush.

To give its humble beginnings a bit of context, Homestake was started in the days of miners hauling loads of ore via horse and mule and the battles of the Great Sioux War. Folk moved about via horse-drawn buggies and Alexander Graham Bell had just made his first successful telephone call.

Wyatt Earp was working in Dodge City, Kansas — he had yet to get the heck outta Dodge — and Mark Twain was in the throes of publishing The Adventures of Tom Sawyer.  — And our dear Thomas Edison had just opened his first industrial research lab in Menlo Park. The mine is part of the Homestake Formation, an Early Proterozoic layer of iron carbonate and iron silicate that produces auriferous greenschist gold. What does all that geeky goodness mean? If you were a gold miner it would be music to your ears. They ground down that schist to get the glorious good stuff and made a tiny wee sum doing so. But then gold prices levelled off — from 1997 ($287.05) to 2001 ($276.50) — and rumblings from the owners started to grow. They bailed in 2001, ironically just before gold prices started up again.

But back to 2001, that levelling saw the owners look to a new source of revenue in an unusual place. One they had explored way back in the 1960s in a purpose-built underground laboratory that sounds more like something out of a science fiction book. The brainchild of chemist and astrophysicists, John Bahcall and Raymond Davis Jr. from the Brookhaven National Laboratory in Upton, New York, the laboratory was used to observe solar neutrinos, electron neutrinos produced by the Sun as a product of nuclear fusion.

Davis had the ingenious idea to use 100,000 gallons of dry-cleaning solvent, tetrachloroethylene, with the notion that neutrinos headed to Earth from the Sun would pass through most matter but on very rare occasions would hit a chlorine-37 atom head-on turning it to argon-37. His experiment was a general success, detecting electron neutrinos,  though his technique failed to sense two-thirds of the number predicted. In particle physics, neutrinos come in three types: electron, muon and tau. Think yellow, green, blue. What Davis had failed to initially predict was the neutrino oscillation en route to Earth that altered one form of neutrino into another. Blue becomes green, yellow becomes blue... He did eventually correct this wee error and was awarded the Nobel Prize in Physics in 2002 for his efforts.

Though Davis’ experiments were working, miners at Homestake continued to dig deep for ore in the belly of the Black Hills of western South Dakota for almost another forty years. As gold prices levelled out and ore quality dropped the idea began to float to re-purpose the mine as a potential site for a new Deep Underground Engineering Laboratory (DUSEL).

A pitch was made and the National Science Foundation awarded the contract to Homestake in 2007.  The mine is now home to the Deep Underground Neutrino Experiment (DUNE) using DUSEL and Large Underground Xenon to look at both neutrinos and dark particle matter. It is a wonderful re-purposing of the site and one that few could ever have predicted. Well done, Homestake. The future of the site is a gracious homage to the now deceased Davis. He would likely be delighted to know that his work continues at Homestake and our exploration of the Universe with it.

Thursday 30 April 2020

HOPLOSCAPHITES

This sweet beauty with lovely oil in water colouring is a Hoploscaphites nebrascensis (Owen, 1852) macroconch. This is the female form of the ammonite, her larger body perfect for egg production by the smaller males, or microconchs of the species.

Hoploscaphites nebrascensis is an upper Maastrichtian species and index fossil. It marks the top of ammonite zonation for the Western Interior. This species has been recorded from Fox Hills Formation in North and South Dakota as well as the Pierre Shale in southeastern South Dakota and northeastern Nebraska.

It is unknown from Montana, Wyoming, and Colorado due to the deposition of coeval terrestrial units. It has possibly been recorded in glacial deposits in Saskatchewan and northern North Dakota, but that is hearsay.

Outside the Western Interior, this species has been found in Maryland and possibly Texas in the Discoscaphites Conrad zone. This lovely one is in the collection of the deeply awesome (and enviable) José Juárez Ruiz. A big thank you to Joshua Slattery for his insights on the distribution of this species.

Wednesday 29 April 2020

LATE JURASSIC PHYLLOCERAS

This lovely creamy beauty is Phylloceras consanguineum (Gemmellaro 1876) a fast-moving carnivorous ammonite from Late Jurassic (Middle Oxfordian) deposits near Sokoja, Madagascar, off the southeast coast of Africa.

This classical Tethyan Mediterranean specimen is very well preserved, showing much of his delicate suturing in intricate detail. Phylloceras were primitive ammonites with involute, laterally flattened shells.

They were smooth, with very little ornamentation, which led researchers to think of them resembling plant leaves and gave rise to their name, which means leaf-horn. They can be found in three regions that I know of.  In the Jurassic of Italy near western Sicily's Rosso Ammonitico Formation, Lower Kimmeridgian fossiliferous beds of Monte Inici East and Castello Inici (38.0° N, 12.9° E: 26.7° N, 15.4° E) and in the Arimine area, southeastern Toyama Prefecture, northern central Japan, roughly, 36.5° N, 137.5° E: 43.6° N, 140.6° E. And in Madagascar, in the example seen here found near Sokoja, Madagascar, off the southeast coast of Africa at 22.8° S, 44.4° E: 28.5° S, 18.2° E.

Tuesday 28 April 2020

HYPHANTOCERAS OF JAPAN

A stunning example of the heteromorph ammonite, Hyphantoceras orientale macroconch. This beauty corresponds to 'Morphotype C' from Aiba (2017). The specimen is a handful at 136 mm and was lovingly prepared by the hand holding it, that of the talented José Juárez Ruiz.

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. The similarity of their shell surface ornamentations and the stratigraphic relationships possibly suggest that H.orientale was derived from H. transitorium. The presumed lineage is likely indigenous to the northwestern Pacific realm in the Santonian–earliest Campanian. Hyphantoceras venustum and H. heteromorphum might stand outside an H. transitorium H. orientale lineage, judging from differences of their shell surface ornamentation.

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.

Monday 27 April 2020

MAMMOTH TUSK: WRANGEL ISLAND

Mammoth Tusk, Wrangel Island, Arctic Ocean
This tusk is from Mammutus primigenius, our beloved Woolly Mammoths, from Wrangel Island in the Arctic Ocean.  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. 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. 

Woolly Mammoths, Mammutus primigenius
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.

How did they use their tusks? Likely for displays of strength, protecting their delicate trunks, digging up ground vegetation and in dry riverbeds, digging holes to get at the precious life-giving water. It's a genius design, really. A bit like having a plough on the front of your skull. In the photo above you can see a tusk washed clean in a creek bed on Wrangel Island.

Their size offered protection against other predators once the mammoth was full grown. Sadly for the juveniles, they offered meaty, 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 of Wrangel in the Arctic Ocean. 

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 26 April 2020

HETEROMORPH AMMONITES

Heteromorph Ammonites, Sowerby 1837
Ammonite shells have been collected by people for millennia. These ammonites are known from the Late Triassic and the middle Jurassic but were most abundant and creative in their form in the Cretaceous (Wiedmann, 1969).

The beautiful plate you see here showing two ammonites is from Sowerby (1837) and is one of the very first scientifically accurate studies of heteromorph ammonites. We see similar species to the heteromorphs above in the Nanaimo Group of Vancouver Island, British Columbia.

During medieval times they were believed to be snakes that had been turned into stone and were sold to people going on pilgrimages. They have been found in archaeological sites in many parts of the world. We find them in archaeological remains spanning human history, across cultures and civilizations.

Pictet's Paleontology Second Edition, 1853-57
Ammonites are prized for their scientific and aesthetic value and have been used as building materials, jewelry, amulets, charms to aid in the hunt, religious totems amongst other things. The original discus used by the ancient Greeks in their Olympics was a fossilized ammonite.

The beautiful plate to the left shows some of the heteromorph ammonites from Pictet's Paleontology in its second edition (1853-57). Some of the figures are copied from Astier or d'Orbigny works, not included in the first edition.

Ammonites are pleasing to the eye, usually taking on a planispiral form— although there are some helically spiralled and fully crazy spiralled forms — known as heteromorphs.

The most interesting of all the heteromorphs are the Cretaceous heteromorph ammonites of the suborder Ancyloceratina. The juveniles of this suborder played with every possible variation in their shell shape from regular planispiral and orthoconic to torticonic, hamitoconic and gyroconic.

The adults uncoiled the last whorl of their shell forming the characteristic U-shaped recurved body chamber you see below. A curious form as the aperture faces upward. Ammonites of the suborder Ancyloceratina may have developed a stationary brooding phase that could have several ecological advantages over free-swimming monomorphic ammonites.

Ancyloceras matheronianus
Alexander Arkipkin wrote a great paper on them in the Journal of Molluscan Studies back in 2014 — "Getting hooked: the role of a U-shaped body chamber in the shell of adult heteromorph ammonites."

His focus is on the morphological features of the adult shell in heteromorph ammonites of the suborder Ancyloceratina but does useful comparisons to a vast number of heteromorph ammonites in collections at the Department of Earth Sciences of the Natural History Museum, London.

Heteromorphs come in a variety of shapes and sizes. They must have intrigued and mystified those who were first to find them as they do not have an intuitive shape at all for a marine predator. Do give Arkipkin's paper a read and bask in the wonder of the amazing forms of these ancient cephalopods.

Reference: Getting hooked: the role of a U-shaped body chamber in the shell of adult heteromorph ammonites. Journal of Molluscan Studies, Volume 80, Issue 4, November 2014, Pages 354–364, https://doi.org/10.1093/mollus/eyu019 https://academic.oup.com/mollus/article/80/4/354/1021718

Image 3-5: Ancyloceras matheronianus. A. General view. B. Inner part of vertical shaft with resolved ribs (RR). C. Inner part of U-shaped adult living chamber with less resolved ribs (WR). Abbreviations as in Figure 2. Scale bar = 1 cm.

Saturday 25 April 2020

OCTOPUS: 300 MILLION YEAR OLD LINEAGE

This lovely with her colourful body is an octopus. Like ninety-seven percent of the world's animals, she lacks a backbone.

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 gone scuba diving at Madrona 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. 

On one of those trips, my friend Suzanne Groulx ran into one of the larger males swimming just offshore. I was surfacing as I heard her shriek clear as a bell. Sound moves through water about four times faster than it does through the air — faster than a jet plane. On that day, I suspect Suzanne was neck and neck both in sound and motion. 

Seconds later, she popped up a good three feet above the surf, still screaming. I have never seen anyone surface quite so quickly — dangerous and impressive in equal measure. It was on another of those trips that I met Philip Torrens, with whom I would later co-author, In Search of Ancient BC.     

While the entire coastline is beautiful to explore, it was visiting the octopus that drew me back time and time again. I have seen wee octopus the size of the palm of your hand, large males swimming and feeding and the lovely females tucked into their nursery homes.

After forty days of mating, the female Giant Pacific Octopus attach strings of small fertilized eggs to the rocks within these crevices and call 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. All the while she is here, she gently blows fresh water over the eggs.

And sadly, this will be her only brood. Octopus breed once in their too-short lives. Males die directly after mating and females die once their young have hatched. They live in all the world's oceans and no matter the species, their lifespans are a brief one to five years. I rather hope they evolve to live longer and one day outcompete the humans who like to snack on them.

Octopus are soft-bodied, eight-limbed molluscs of the order Octopoda. They have one hard part, their beaks, which they use to crack open clams, crab and crustaceans. They are ninja-level skilled at squeezing through very tight holes, particularly if it means accessing a tasty snack. The size of their beaks determines exactly how small a hole they can fit through. Looking, you would likely guess it could not be done, but they are amazing — and mesmerizing!

At the Vancouver Aquarium, they have been known to unscrew lids, sneak out of one tank to feed in another then slip back so you do not notice, open simple hooks and latches — burglars of the sea. They can also change the colour and texture of their skin to blend perfectly into their surroundings. You can look for them around reefs and rocky shores. There are 300 species of octopus grouped within the class Cephalopoda, along with squid, 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).

My favourite fossil octopus is the darling Keuppia levante (Fuchs, Bracchi & Weis, 2009), an extinct genus of octopus that swam our ancient seas back in the Cretaceous.

Friday 24 April 2020

ETHELDRED BENETT: SPONGE HUNTRESS

Hoplites (Hoplites) bennettiana (Sowerby, 1826)
A beautiful example of the ammonite, Hoplites (Hoplites) bennettiana (Sowerby, 1826), from Early Albian localities in the Carrière de Courcelles Villemoyenne, Région de Troyes, near Champagne in northeastern France.

The species name is an homage to Etheldred Benett, an early English geologist often credited with being the first female geologist — a fossil collector par excellence.

She was also credited with being a man  —  the Natural History Society of Moscow awarding her membership as Master Etheldredus Benett in 1836. The confusion over her name (it did sound masculine) came again with the bestowing of a Doctorate of Civil Law from Tsar Nicholas I.

The Tsar had read Sowerby's Mineral Conchology, a major fossil reference work which contained the second-highest number of contributed fossils of the day, many the best quality available at the time. Forty-one of those specimens were credited to Benett. Between her name and this wonderous contribution to a growing science, the Russian Tsar awarded the Doctorate to what he believed was a young male scientist on the rise. He believed in education, founding Kiev University in 1834, just not for women. He was an autocratic military man frozen in time — the thought that this work could have been done by a female unthinkable. Doubly charming is that the honour from the University of St Petersburg was granted at a time when women were not allowed to attend St. Pete's or any higher institutions. That privilege arrived in 1878, twenty years after Nicholas I's death.

Benett took these honours (and social blunders) with grace. She devoted her life to collecting and studying fossils from the southwest of England, amassing an impressive personal collection she openly shared with geologist friends, colleagues and visitors to her home. Her specialty was fossils from the Middle Cretaceous, Upper Greensand in the Vale of Wardour — a valley in the county of Wiltshire near the River Nadder.

Etheldred was a local Wiltshire girl. Born Etheldred Benett on 22 July 1775 at Pyt House, Tisbury, Wiltshire, the eldest daughter of the local squire Thomas Benett. Etheldred's interest was cultivated by the botanist Aylmer Bourke Lambert (1761-1842), a founding member of the Linnean Society. Benett's brother had married Lucy Lambert, Aylmer's half-sister. Aylmer was a Fellow of the Royal Society and the Society of the Arts. He was also an avid fossil collector and member of the Geological Society of London. The two met and got on famously.

Aylmer kindled an interest in natural history in both of Benett's daughters. Etheldred had a great fondness in geology, stratigraphy and all things paleo, whilst her sister concentrated on botany. Etheldred had a distinct advantage over her near contemporary, the working-class Mary Anning (1799-1847), in that Benett was a woman of independent wealth who never married — and didn't need to — who could pursue the acquisition and study of fossils for her own interest.

While Anning was the marine reptile darling of the age, she was also greatly hindered by her finances. "She sells, seashells by the seashore..." while chanted in a playful spirit today, was not meant kindly at the time. Aylmer's encouragement emboldened Etheldred to go into the field to collect for herself — and collect she did. Profusely.

Benett’s contribution to the early history of Wiltshire geology is significant. She corresponded extensively with the coterie of gentlemen scientists of the day —  Gideon Mantell, William Buckland, James Sowerby, George Bellas Greenough and, Samuel Woodward. She also consorted with the lay folk and had an ongoing correspondence with William Smith, whose stratigraphy work had made a favourable impression on her brother-in-law, Aylmer.

Her collections and collaboration with geologists of the day were instrumental in helping to form the field of geology as a science. One colleague and friend, Gideon Mantell, British physician, geologist and paleontologist, who discovered four of the five genera of dinosaurs and Iguanadon, was so inspired by Benett's work he named this Cretaceous ammonite after her — Hoplites bennettiana.

Benett's fossil assemblage was a valuable resource for her contemporaries and remains so today. It contains thousands of Jurassic and Cretaceous fossil specimens from the Wiltshire area and the Dorset Coast, including a myriad of first recorded finds. The scientific name of every taxon is usually based on one particular specimen, or in some cases multiple specimens. Many of the specimens she collected serve as the Type Specimen for new species.

Fossil Sponge, Polypothecia quadriloba, Warminster, Wiltshire
Her particular interest was the collection and study of fossil sponges. Alcyonia caught her eye early on. She collected and recorded her findings with the hope that one of her colleagues might share her enthusiasm and publish her work as a contribution to their own.

Alas, no one took up the helm — those interested were busy with other pursuits (or passed away) and others were less than enthusiastic or never seemed to get around to it.

To ensure the knowledge was shared in a timely fashion, she finally wrote them up and published them herself. You can read her findings in her publication, ‘A Catalogue of Organic Remains of the County of Wiltshire’ (1831), where she shares observations on the fossil sponge specimens and other invert goodies from the outcrops west of town.

She shared her ideas freely and donated many specimens to local museums. It was through her exchange of observations, new ideas and open sharing of fossils with Gideon Mantell and others that a clearer understanding of the Lower Cretaceous sedimentary rocks of Southern England was gained.

In many ways, Mantell was drawn to Benett as his ideas went against the majority opinion. At a time when marine reptiles were dominating scientific discoveries and discussions, he pushed the view that dinosaurs were terrestrial, not amphibious, and sometimes bipedal. Mantell's life's work established the now-familiar idea that the Age of Reptiles preceded the Age of Mammals. Mantell kept a journal from 1819-1852, that remained unpublished until 1940 when E. Cecil Curwen published an abridged version. (Oxford University Press 1940). John A. Cooper, Royal Pavilion and Museums, Brighton and Hove, published the work in its entirety in 2010.

I was elated to get a copy, both to untangle the history of the time and to better learn about the relationship between Mantell and Benett. So much of our geologic past has been revealed since Mantell's first entry two hundred years ago. The first encounter we share with the two of them is a short note from March 8, 1819. "This morning I received a letter from Miss Bennett of Norton House near Warminster Wilts, informing me of her having sent a packet of fossils for me, to the Waggon Office..." The diary records his life, but also the social interactions of the day and the small connected community of the scientific social elite. It is a delight!

Though a woman in a newly evolving field, her work, dedication and ideas were recognized and appreciated by her colleagues. Gideon Mantell described her as, "a lady of great talent and indefatigable research," whilst the Sowerbys noted her, "labours in the pursuit of geological information have been as useful as they have been incessant."

Benett produced the first measured sections of the Upper Chicksgrove quarry near Tisbury in 1819, published and shared with local colleagues as, "the measure of different beds of stone in Chicksgrove Quarry in the Parish of Tisbury.” The stratigraphic section was later published by naturalist James Sowerby without her knowledge. Her research contradicted many of Sowerby’s conclusions.

She wrote and privately published a monograph in 1831, containing many of her drawings and sketches of molluscs and sponges. Her work included sketches of fossil Alcyonia (1816) from the Green Sand Formation at Warminster Common and the immediate vicinity of Warminster in Wiltshire.

Echinoids and Bivalves. Collection of Etheldred Benett (1775-1845)
The Society holds two copies, one was given to George Bellas Greenough, and another copy was given to her friend Gideon Mantell. This work established her as a true, pioneering biostratigrapher following but not always agreeing with the work of William Smith.

If you'd like to read a lovely tale on William's work, check out the Map that Changed the World: William Smith and the Birth of Modern Geology by Simon Winchester. It narrates the intellectual context of the time, the development of Smith's ideas and how they contributed to the theory of evolution and more generally to a dawning realization of the true age of the earth.

The book describes the social, economic or industrial context for Smith's insights and work, such as the importance of coal mining and the transport of coal by means of canals, both of which were a stimulus to the study of geology and the means whereby Smith supported his research. Benett debated many of the ideas Smith put forward. She was luckier than Smith financially, coming from a wealthy family, a financial perk that allowed her the freedom to add fossils to her curiosity cabinet at will.

Most of her impressive collection was assumed lost in the early 20th century. It was later found and purchased by an American, Thomas Bellerby Wilson, who donated it to the Academy of Natural Sciences of Philadelphia. Small parts of it made their way into British museums, including the Leeds City Museum, London, Bristol and to the University of St. Petersburg. These collections contain many type specimens and some of the very first fossils found — some with the soft tissues preserved. When Benett died in 1845, it was Mantell who penned her obituary for the London Geological Journal.

In 1989, almost a hundred and fifty years after her death, a review of her collection had Arthur Bogen and Hugh Torrens remark that her work has significantly impacted our modern understanding of Porifera, Coelenterata, Echinodermata, and the molluscan classes, Cephalopoda, Gastropoda, and Bivalvia. A worthy legacy, indeed.

Her renown lives on through her collections, her collaborations and through the beautiful 110 million-year-old ammonite you see here, Hoplites bennettiana. The lovely example you see here is in the collection of the deeply awesome Christophe Marot.

Spamer, Earle E.; Bogan, Arthur E.; Torrens, Hugh S. (1989). "Recovery of the Etheldred Benett Collection of fossils mostly from Jurassic-Cretaceous strata of Wiltshire, England, analysis of the taxonomic nomenclature of Benett (1831), and notes and figures of type specimens contained in the collection". Proceedings of the Academy of Natural Sciences of Philadelphia. 141. pp. 115–180. JSTOR 4064955.

Torrens, H. S.; Benamy, Elana; Daeschler, E.; Spamer, E.; Bogan, A. (2000). "Etheldred Benett of Wiltshire, England, the First Lady Geologist: Her Fossil Collection in the Academy of Natural Sciences of Philadelphia, and the Rediscovery of "Lost" Specimens of Jurassic Trigoniidae (Mollusca: Bivalvia) with Their Soft Anatomy Preserved.". Proceedings of the Academy of Natural Sciences of Philadelphia. 150. pp. 59–123. JSTOR 4064955.

Photo credit: Fossils from Wiltshire.  In the foreground are three examples of the echinoid, Cidaris crenularis, from Calne, a town in Wiltshire, southwestern England, with bivalves behind. Caroline Lam, Archivist at the Geological Society, London, UK. http://britgeodata.blogspot.com/2016/03/etheldred-benett-first-female-geologist_30.html

Photo credit: Fossil sponges Polypothecia quadriloba, from Warminster, Wiltshire. The genus labels are Benett’s, as is the handwriting indicating the species. The small number, 20812, is the Society’s original accession label from which we can tell that the specimen was received in April 1824. The tablet onto which the fossils were glued is from the Society’s old Museum.