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. 

Megalosaurus

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.

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/

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.

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.

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

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

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.

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.

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.

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.

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.

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

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.