AMMOLITE: LOVE, GREED AND GLORY

Ammolite from the Bearpaw Formation

Ammolite is an opal-like organic gemstone found primarily along the eastern slopes of the Rocky Mountains of North America. 

The mining of ammolite is a serious business. I happened upon a locality while in search of fossilized oysters along the St. Mary's River in Alberta. It was one of the few times that I have ever been shot at. 

They sunk the wee boat I was using as a raft to haul my finds but I will give them credit for firing warning shots and not actually trying to hit me. With that, I can safely say that ammolite inspires strong emotions amongst fossil collectors — love, greed and glory. 

It is made of the fossilized shells of ammonites, which in turn are composed primarily of aragonite, the same mineral contained in shell nacre, with a microstructure inherited from the shell. It is one of few biogenic gemstones along with amber and pearl.

The chemical composition of ammolite is variable. Aside from aragonite, it may include a mix of calcite, silica, pyrite or wee bits and pieces of other minerals. The shell itself may contain a number of trace elements based on the chemical composition of the original sediments where it was fossilized and chemical goodies carried in from groundwater. Most anything can be found in the mix, but primarily we see aluminium, barium, chromium, copper, iron, magnesium, manganese, strontium, titanium, and vanadium. 

Its crystallography is orthorhombic, a seven-sided crystal system. Its hardness is 3.5–4.5, and its specific gravity is 2.60–2.85. The refractive index of Canadian material (as measured via sodium light, 589.3 nm) is as follows: α 1.522; β 1.672–1.673; γ 1.676–1.679; biaxial negative. Under ultraviolet light, ammolite may fluoresce a mustard yellow.

Ammolite comes from the fossil shells of the Upper Cretaceous disk-shaped ammonites Placenticeras meeki and Placenticeras intercalare, and to a lesser degree, the cylindrical baculite, Baculites compressus. The ammonites that form our Alberta ammolite inhabited a prehistoric, inland subtropical sea that bordered the Rocky Mountains — the Cretaceous Western Interior Seaway. 

As the cephalopods died, they sank to the bottom and were buried by layers of bentonitic mud that eventually became shale. Many gem-quality ammonites are found within siderite concretions. These sediments preserved the aragonite of the shells, preventing them from converting to calcite.

Ammolite: Colourful Microstructure of Aragonite

An iridescent opal-like play of colour is shown in fine specimens in shades of yellow, orange, red, green and gold. 

The iridescence is due to the microstructure of the aragonite: unlike most other gems, whose colours come from light absorption, the iridescent colour of ammolite comes from interference with the light that rebounds from stacked layers of thin platelets that make up the aragonite. 

The thicker the layers, the more reds and greens are produced; the thinner the layers, the more blues and violets predominate. Reds and greens are the most commonly seen colours, owing to the greater fragility of the finer layers responsible for the blues. 

When freshly quarried, these colours are not especially dramatic; the material requires polishing and other treatments to reveal the specimen's full-colour potential.

Ammolite itself is quite thin, generally 0.5–0.8 millimetres (0.02–0.03 inches) thick. This thin coating covers a matrix typically made up of grey to brown shale, chalky clay, or limestone. Truly, when you find these ammonites in the field, they do not look like much. They are perhaps a nice shape but often matte grey and unappealing until prepared.  

Frost shattering of these specimens is common. If left exposed to the elements the thin ammolite tends to crack and flake. Prolonged exposure to sunlight can also lead to bleaching of the generally intense colouration. The cracking results in a tessellated appearance, sometimes described as a "dragon skin" or referred to as a stained glass window pattern. 

Ammolite mined from deeper deposits may be entirely smooth or with a rippled surface. Occasionally a complete ammonite shell is recovered with its structure well-preserved: fine, convoluted lines delineate the shell chambers, and the overall shape is suggestive of a nautilus. While these shells may be as large as 90 centimetres (35.5 inches) in diameter, the iridescent ammonites — as opposed to the pyritized variety — are typically much smaller. Most fossilized shells have had their aragonite pseudomorphously replaced by calcite or pyrite, making the presence of ammolite particularly uncommon.

In 1981, ammolite was given official gemstone status by the World Jewellery Confederation (CIBJO), the same year commercial mining of ammolite began. It was designated the official gemstone of the City of Lethbridge, Alberta in 2007.

Ammolite is also known as aapoak — Kainah for "small, crawling stone" — gem ammonite, calcentine, and Korite. The latter is a Trade name given to the gemstone by the Alberta-based mining company Korite. Roughly half of all ammolite deposits are contained within the Kainah (Kainaiwa) reserve, and its inhabitants play a major role in ammolite mining. Marcel Charbonneau and his business partner Mike Berisoff were the first to create commercial doublets of the gem in 1967. They went on to form Ammolite Minerals Ltd.

BELEMNITES: SQUID-LIKE CEPHALOPODS

Lower Jurassic Belemnites, Photo: Georg Laki

Belemnitida is an extinct order of squid-like cephalopods that swam our ancient seas from the Late Triassic to Late Cretaceous. 

Unlike squid, belemnites had an internal skeleton that made up the cone and it is this hard part that we often find fossilized. 

The parts are, from arms to tip: the tongue-shaped pro-ostracum, the conical phragmocone, and the pointy guard.  

When you find these as fossils, it is not intuitive as to what kind of animal they came from. This is the internal hard part of a rather soft, squishy squid-like fellow. 

Because the softer bits are often scavenged and decay, we rarely see them fossilized. Instead, we get what looks like a pointy selection of cigar-shaped goodies that are all that is left of these marine cephalopods. 

We find this fossil in many places around the world. Some friends shared where they have personally found them which I thought might be of interest to you. Arno Martini has found them in northern California, Anne Glenn finds them in Wyoming, Marco Valentin has an enviable collection from Hannover, Misburg, Germany, Juanjo Ugalde Robledo finds them in La Rioja, Spain, Barbara Hnb finds them in Normandy, Patrick Buster finds them in the Navesink Formation of New Jersey, Kim Pervis shared a monograph on Mississippian Belemnites by Rousseau. 

Georg Laki has collected many of their number in the Early Jurassic (Sinemurian/Pliensbachian) of South Luxembourg at Gasperich. I included a photo of Georg's belemnites (with permission) here for you to enjoy. He has a lovely collection that shows the variety of these fossils. 

Anatomy of a Belemnite Fossil

Other notable finds are from Scott Carpenter and his daughter who collect them on the Jurassic Coast, Gabriel Santos who collects them in Peniche, Portugal and Rossi Franco shared a belemnite he found in the building materials used to construct the Bank of Italy in Genoa. 

There are also some wonderfully preserved plates of multiple Jurassic belemnites from Mistelgau, Germany you may want to take a boo at. Imagine slate grey to honey brown Youngibelus and Paxillosus clusters on a beige matrix. Quite stunning. 

I have found them around British Columbia, as has Lloyd Rempel, including at Harrison Lake, British Columbia, Canada. 

UPPER CRETACEOUS TOOTHED BIRDS IN SOUTH AMERICA

70-Million-Year-Old Toothed Enantiornithes Bird Beak

Teeth and jaws, beaks and claws — all species adapt and change over time based on survival. One of the key features of being alive is needing to eat. Depending on what is on the menu, we adapt accordingly. 

I had been thinking about this from a very mammal-centric perspective, but it is true for all animals — birds included.

When we think of our feathered friends, we think of beaks and feathers. True, birds descend from the mighty lineage of dinosaurs, but our experience of them is of their modern forms. 

This modern viewpoint of their characteristics makes beaks with teeth seemingly more fantasy than reality — except this has not always been the case. 70 million years ago, birds flying our Cretaceous skies in what would become South America, Europe and Asia had teeth embedded in their beaks.

The discovery of polyphyodonty and dental replacement in toothed stem birds dates back to the nineteenth century. Marsh reported replacement teeth inside resorption pits in the Late Cretaceous Hesperornis and Ichthyornis.

Enantiornithine Birds & Cladogram

The birds that inhabit the current biomes do not have teeth, but the primitive birds found as fossils in the Upper Cretaceous of Brazil certainly did. 

These ancient relatives to our modern fauna had teeth embedded in their jaw-beaks, clawed fingers and a long tail. 

Both these ancient birds and their modern cousins are descended from the dinosaurs, more specifically the Maniraptora, that clade of coelurosaurian dinosaurs characterized by long arms and three-fingered hands — reduced or fused in some lineages — and semi-lunate or half-moon shaped bone in their wrists you will know as the carpus. 

As with all the dinosaurs in this clad, they had teeth and lots of them.

William Nava, head of the Marília Museum of Paleontology, São Paulo, Brazil, uncovered an outcrop in the city of Presidente Prudente with abundant fossilized bird bones. 

Bird bones are a rare thing as they are delicate, often scavenged before burial and hollow, making them poor candidates for preservation. While bird bones preserved as fossils are generally rare, this was not the case at William's Quarry. The site was a smorgasbord of bones from a number of primitive bird species that lived at the end of the Cretaceous. 

The birds belong to the group of Enantiornithes who looked very much like our modern birds on the outside, but internally they had clawed fingers on each wing and teeth which they replaced in a similar fashion to most reptiles. 

Two other sites have exceptionally preserved Enantiornithes bones. Since most Enantiornithes bones are fragmentary, some species are only known from a piece of a single bone. We are luckier at some sites than others. Almost all complete, fully articulated fossil specimens with soft tissue preserved were known from Las Hoyas in Cuenca, Spain and the Jehol group in Liaoning, China. But the fossil outcrops in the Adamantina Formation, Bauru Group of Brazil can now be added to that very short list.  

If you fancy a read, check out their publication, Dental replacement in Mesozoic birds: evidence from newly discovered Brazilian enantiornithines.” The team included Yun-Hsin Wu and Luis M. Chiappe of the Natural History Museum of Los Angeles County, David J. Bottjer of the University of Southern California, William Nava from the Marília Museum of Paleontology, and Agustín G. Martinelli from the Vertebrate Paleontology Section of the Bernardino Rivadavia Argentine Museum of Natural Sciences.

Publication link: https://www.nature.com/articles/s41598-021-98335-8

Images: Photographs of the enantiornithine specimens MPM-90, MPM-373, and MPM-351, and a simplified cladogram highlighting the stem avian taxa discussed in this study. MPM-373: (a) dorsal view; (b) right lateral view; (c) left lateral view. MPM-90: (d) dorsal view; (e) right lateral view. MPM-351: (f) left lateral view. En external nares, Fp frontal process. With an embedded illustration of a reconstruction of Sinornis santensis by McBlackneck. There is some mice type used so feel free to click the image to see if full size.

The studied specimens consist of two sets of premaxillae (MPM-90 and MPM-373) and an incomplete left dentary (MPM-351) exquisitely preserved in three dimensions. These specimens are housed at the Museu de Paleontologia de Marília (MPM), São Paulo State, Brazil.

CADOCHAMOUSSETIA: FROM RUSSIA WITH LOVE

From Russia with love. This lovely inflated ammonite is the female macroconch, Cadochamoussetia tschernyschewi (Sokolov, 1912) from the Jurassic, Lower Callovian, Elatmae Zone, Subpatruus Subzone, Stupachenkoi Horizon, Unzha River, Makarev-Manturovo, Kostroma Region, Russia.

This beautiful — fully Бомба — specimen is courtesy of Emil Black and one of the finest in his collection. 

It has a chunkiness that reminds me of the Cadoceras we find in the Pacific Northwest, particularly the macroconch Cadoceras comma from the Callovian Mysterious Creek Formation near Harrison Lake in British Columbia.

In the last decade, the Siberian zonal scale of the Callovian has been considerably revised because of new ammonite collections from the Callovian reference sections in Siberia. Species of Cadoceratinae thought of as exclusively European were recorded for the first time in Siberia. 

Both these newly recovered specimens and recent studies have considerably expanded our knowledge on the taxonomic composition of genera and species of Callovian ammonites and revision of the generic classification and stratigraphic position of genera and species of the family Cardioceratidae. The proposed Lower Callovian ammonite scale largely coincides with the East European scale and correlates with the scales of East Greenland, Arctic Canada, and Alaska (Kniazev et al., 2009, 2010, 2011, 2015; Nikitenko et al., 2013).

Jurassic deposits crop out on the right bank of the

Anabar River between the mouths of the Srednyaya

and Sodiemykha rivers, over a length of about 24 km.

During recent fieldwork at the Middle-Upper Jurassic of the Anabar River basin, a lovely representative ammonite collection was assembled, amongst which was the Early Callovian genus Cadochamoussetia (Mitta, 1996). 

Cadochamoussetia is widespread in East European sections but these beauties were the first recorded specimen of this chunky species from the Anabar.

The genus Cadochamoussetia (Mitta, 1996) was established in European Russian (Gerasimov et al., 1996) and later in England (Navarro et al., 2005).

In the lower Callovian of European Russia, beds with Cadochamoussetia were originally considered part of the Cadochamoussetia subpatruus upper subzone of the Cadoceras elatmae Zone (Mitta, 2000). 

In 2005 and 2009, proposals were made to move these beds from subzone to zone (Gulyaev, 2005, 2009). However, the Unified Regional Stratigraphic Scheme of Jurassic Deposits of the East European Platform (2012), suggested it remained a subzone. The Anabar section contains two species of Сadochamoussetia, which were used as the basis of the Сadochamoussetia tschernyschewi Zone.

In previous papers (Kniazev et al., 2010), considered the composition of the genus Cadoceras as it was interpreted in (Treatise, 1957). 

Several groups of species are now recognized within the genus: Cadoceras elatmae group, including C. frearsi, C. harveyi, C. sublaeve, including species widespread in the Arctic C. tolype, C. emelianzevi, C. septentrionale, C. durum, etc. 

Kniazev et al. proposed assigning a group of Bathonian species Catacadoceras laptievi, C. barnstoni, C. perrarum, C. subcatastoma, and C. nageli.

Photos: Cadochamoussetia tschernyschewi (12 cm) graciously shared by the deeply awesome of Emil Black. He has shared many wonderful specimen photos and stories with me over the years and I am honoured by his generosity in doing so. It is because of him that I am able to share these with all of you! So a collective, Спасибо, мой друг. Spasibo, moy drug. 

I have placed views of this lovely Cadochamoussetia tschernyschewi into a teaching tool that includes the specimen name, length and provenance.

References:

• The Early Callovian genus Сadochamoussetia (Ammonoidea, Cardioceratidae) in the lower reaches of the Anabar River, Northern Central Siberia; Original Russian Text © V.G. Kniazev, S.V. Meledina, A.S. Alifirov, B.L. Nikitenko, 2017, published in Stratigrafiya, Geologicheskaya Korrelyatsiya, 2017, Vol. 25, No. 4, pp. 26–41.
• Kniazev, V.G., Meledina, S.V., Alifirirov, A.S., and Kutygin, R.V., The Middle Callovian stage of evlution of Siberian cardioceratids, in Sovremennye problemy izucheniya golovonogikh mollyuskov. Morfologiya, sistematika, evolyutsiya, ekologiya i biostratigrafiya. Vyp. 4 (Current Problems in Study of Cephalopods: Morphology, Systematics, Evolution, Ecology, and Biostratigraphy. Iss. 4), Moscow: Paleontol. Inst. Ross. Akad. Nauk, 2015, pp. 40–45.
• Meledina, S.V, Correlation of the Bajocian and Bathonian zones in light of new paleontological data, Stratigr. Geol. Correl., 2014, vol. 22, no. 6, pp. 594–605.
• Kniazev, V.G., Meledina, S.V., Alifirirov, A.S., and Kutygin, R.V., The Middle Callovian stage of evlution of Siberian cardioceratids, in Sovremennye problemy izucheniya golovonogikh mollyuskov. Morfologiya, sistematika, evolyutsiya, ekologiya i biostratigrafiya. Vyp. 
• If you do not speak Russian that roughly translates to: Current Problems in Study of Cephalopods: Morphology, Systematics, Evolution, Ecology, and Biostratigraphy. Iss. 4, Moscow: Paleontol. Inst. Ross. Akad. Nauk, 2015, pp. 40–45.
• Meledina, S.V, Correlation of the Bajocian and Bathonian zones in light of new paleontological data, Stratigr. Geol. Correl., 2014, vol. 22, no. 6, pp. 594–605.
• Treatise on Invertebrate Paleontology. Pt. L. Mollusca 4, Cephalopoda, Ammonoidea, N.Y. Lawrence: Geol. Soc. Amer., Univ. Kansas Press, 1957, vol. 4. TSCreatorProvisualization of Enhanced Geologic Time Scale 2004 database (Vers. 6.2, 2014). http://www.tscreator. org, 2014.
• Treatise on Invertebrate Paleontology. Pt. L. Mollusca 4, Cephalopoda, Ammonoidea, N.Y. Lawrence: Geol. Soc. Amer., Univ. Kansas Press, 1957, vol. 4. TSCreatorProvisualization of Enhanced Geologic Time Scale 2004 database (Vers. 6.2, 2014). http://www.tscreator. org, 2014.

ETHELDRED'S HOPLITES

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 a 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 that contained the second-highest number of contributed fossils of the day, many of 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 Kyiv 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 speciality 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 Benett was born 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 for 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 palaeontologist, 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 we gained a clearer understanding of the Lower Cretaceous sedimentary rocks of Southern England.

In many ways, Mantell was drawn to Benett as his ideas went against 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 and the social interactions of the small connected community of the scientific social elite — pure 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. Bits of her collection made their way into British museums. Leeds City Museum, the British Museum in London, Bristol Museum and the University of St. Petersburg all house her specimens. These collections contain many of the first fossils found of their kind — some with the soft tissues preserved. When Benett died in 1845, it was Mantell who penned her obituary for the London Geological Journal.

Etheldred Benett (1776-1845)

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.

https://www.strangescience.net/ebenett.htm

FOSSIL HUNTRESS PODCAST

The first episode of the Fossil Huntress Podcast was October 12, 2020. It started with a bang of 47 episodes in the first season. 

Since then, I have slowed down a bit to deliver 85 episodes over the course of this past year. 

The podcast has gained a broad audience globally with over 10,000 listens from 65 countries. It attracts those who love the realm of palaeontology with its sexy ammonites, trilobites and dinosaurs, but also a general science audience of those who love the natural world. 

The podcast has changed the way I interact with those who read my work and made me a better storyteller — though, in truth, I am still learning. 

With a large part of my listeners speaking English as their second, third or fourth language, it has made me aware of the many idioms and gambits so common in our English tongue. I have added a translate button to the ARCHEA blog so folk can read it in their language of choice as much of what I share on the podcast is also shared via the blog — only with pictures instead of descriptions.  

DORSET LYTOCERAS

A superbly prepped and extremely rare Lytoceras (Suess, 1865) ammonite found as a green ammonite nodule by Matt Cape in the Lower Lias of Dorset. 

Lytoceras are rare in the Lower Lias of Dorset — apart from the Belemnite Stone horizon — so much so that Paul Davis, whose skilled prep work you see here, initially thought it might be a Becheiceras hidden within the large, lumpy nodule. 

One of the reasons these lovelies are rarely found from here is that they are a Mediterranean Tethyian genus. The fossil fauna we find in the United Kingdom are dominated by Boreal Tethyian genera. 

We do find Lytoceras sp. in the Luridum subzone of the Pliensbachian showing that there was an influx of species from the Mediterranean realm during this time. This is the first occurrence of a Lytoceras that he has ever seen in a green nodule and Paul's seen quite a few. 

This absolutely cracking specimen was found and is in the collections of the awesome Matt Cape. Matt recognized that whatever was hidden in the nodule would take skilled and careful preparation using air scribes. Indeed it did. It took more than five hours of time and skill to unveil the lovely museum-worthy specimen you see here. 

We find Lytoceras in more than 1,000 outcrops around the globe ranging from the Jurassic through to the Cretaceous, some 189.6 to 109.00 million years ago. Once this specimen is fully prepped with the nodule material cut or scraped away, you can see the detailed crinkly growth lines or riblets on the shell and none of the expected coarse ribbing. 

Lytoceras sp. Photo: Craig Chivers

If you imagine running your finger along these, you would be tracing the work of decades of growth of these cephalopods. 

While we cannot know their actual lifespans, but we can make a healthy guess. 

The nautilus, their closest living cousins live upwards of 20 years — gods be good — and less than three years if conditions are poor.

The flanges, projecting flat ribs or collars, develop at the edge of the mouth border on the animal's mantle as they grow each new chamber. 

Each delicate flange grows over the course of the ammonites life, marking various points in time and life stages as the ammonite grew. There is a large variation within Lytoceras with regards to flanges. They provide both ornamentation and strength to the shell to protect it from water pressure as they moved into deeper seas.

The concretion prior to prep

This distinctive genus with its evolute shells are found in the Cretaceous marine deposits of: 

Antarctica (5 collections), Austria (19), Colombia (1), the Czech Republic (3), Egypt (2), France (194), Greenland (16), Hungary (25), Italy (11), Madagascar (2), Mexico (1), Morocco (4), Mozambique (1), Poland (2), Portugal (1), Romania (1), the Russian Federation (2), Slovakia (3), South Africa (1), Spain (24), Tanzania (1), Trinidad and Tobago (1), Tunisia (25); and the United States of America (17: Alaska, California, North Carolina, Oregon).

We also find them in Jurassic marine outcrops in:

Austria (15), Canada (9: British Columbia), Chile (6), France (181), Germany (11), Greenland (1), Hungary (189), India (1), Indonesia (1), Iran (1), Italy (50), Japan (14), Kenya (2), Luxembourg (4), Madagascar (2), Mexico (1), Morocco (43), New Zealand (15), Portugal (1), Romania (5), the Russian Federation (1), Slovakia (1), Spain (6), Switzerland (2), Tunisia (11), Turkey (12), Turkmenistan (1), Ukraine (5), the United Kingdom (12), United States (11: Alaska, California) — in at least 977 known collections. 

References:

Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2008-05-07. Retrieved 2017-10-18.

Paleobiology Database - Lytoceras. 2017-10-19.

Systematic descriptions, Mesozoic Ammonoidea, by W.J Arkell, Bernhard Kummel, and C.W. Wright. 1957. Treatise on Invertebrate Paleontology, Part L. Geological Society of America and University of Kansas press.

SHORT-BEAKED ECHIDNA

This chunky monkey is a Short-beaked Echidna, Tachyclossus aculeatus, which grows to about the size of an overweight cat. They are native to Australia and New Guinea. 

Echidnas are sometimes called spiny anteaters and belong in the family Tachyglossidae (Gill, 1872). They are monotremes, an order of egg-laying mammals. 

There are four species of echidnas living today. They, along with the platypus, are the only living mammals who lay eggs and the only surviving members of the order Monotremata. 

Superficially, they resemble the anteaters of South America and other spiny mammals like porcupines and adorable hedgehogs. They are usually a mix of brown, black and cream in colour. While rare, there have been several reported cases of albino echidnas, their eyes pink and their spines white. Echidnas have long, slender snouts that act as both nose and mouth for these cuties. The Giant Echidna we see in the fossil record had beaks more than double this size.  

Like the platypus, they are equipped with electro sensors, but while the platypus has 40,000 electroreceptors on its bill, the long-beaked echidna has only 2,000. The short-beaked echidna, which lives in a drier environment, has no more than 400 at the tip of its snout.

Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. Their ancestors were aquatic, but echidnas have adapted to life on land. Today, they weigh in at about 7 kg today but back in the Pleistocene, they were much larger. The Giant Echnida, Megalibwilia ramsayi was about 10% larger at 10 kg and Zaglossus hacketti was a whopping 30 kg. 

Fossil remains are relatively rare and sadly, incomplete, but they tell us potentially two other species of Echidna thriving in the Pleistocene. We also find Robust Echidna, Zaglossus robustus, in slightly older Miocene aged outcrops in a goldmine in Australia. The Giant Echnida's we find in the fossil record are relatives of the Long-Beaked Echidnas who live in New Guinea today.      

ICE AGE MANATEES

Manatees do not live year-round in Texas, but these gentle sea cows are known to occasionally visit, swimming in for a summer vacation and returning to warmer waters for the winter. 

Interestingly, we have recently found fossil evidence for manatees along the Texas coast dating back to the most recent ice age. 

The discovery raises questions about whether manatees have been visiting for thousands of years, or if an ancient population of ice age manatees once called Texas home.

The findings were published in Palaeontologia Electronica by lead author Christopher Bell, a professor at the UT Jackson School of Geosciences with co-authors Sam Houston State University Natural History Collections curator William Godwin and SHSU alumna Kelsey Jenkins — now a graduate student at Yale University — and SHSU Professor Patrick Lewis.

The eight fossils described in the paper include manatee jawbones and rib fragments from the Pleistocene, the geological epoch of the last ice age. Most of the bones were collected from McFaddin Beach near Port Arthur and Caplen Beach near Galveston during the past 50 years by amateur fossil collectors who donated their finds to the SHSU collections.

The Jackson Museum of Earth History at UT holds two of the specimens. A lower jawbone fossil, which was donated to the SHSU collections by amateur collector Joe Liggio, jumpstarted the research.

Manatee jawbones have a distinct S-shaped curve that immediately caught Godwin's eye. But Godwin said he was met with scepticism when he sought other manatee fossils for comparison. He recalls reaching out to a local fossil enthusiast who told him point-blank, "there are no Pleistocene manatees in Texas."

But an examination of the fossils by Bell and Lewis proved otherwise. The bones belonged to the same species of manatee that visits the Texas coast today, Trichechus manatus. An upper jawbone donated by U.S. Rep. Brian Babin was found to belong to an extinct form of the manatee, Trichechus manatus bakerorum.

The age of the manatee fossils is based on their association with better-known ice age fossils and paleo-Indian artefacts that have been found on the same beaches.

It is assumed that the cooler ice age climate would have made Texas waters even less hospitable to manatees than they are today. But the fact that manatees were in Texas — whether as visitors or residents — raises questions about the ancient environment and ancient manatees. The Texas coast stretched much farther into the Gulf of Mexico and hosted wider river outlets during the ice age than it does today. Either the coastal climate was warmer than is generally thought, or ice age manatees were more resilient to cooler temperatures than manatees of today.

Subsurface imaging of the now flooded modern continental shelf reveals both a greater number of coastal embayments and the presence of significantly wider channels during ice age times.

If there was a population of ice age manatees in Texas, it is entirely plausible that they would have ridden out winters in these warmer river outlets similar to how they do today in Florida and Mexico.

Reference: Christopher Bell, William Godwin, Kelsey Jenkins, Patrick Lewis. First fossil manatees in Texas: Trichechus manatus bakerorum in the Pleistocene fauna from beach deposits along the Texas Coast of the Gulf of Mexico. Palaeontologia Electronica, 2020; DOI: 10.26879/1006

GULLS: TSIK'WI

A gull cries in protest at not getting his share of a meal

Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. 

The Laridae are known from not-yet-published fossil evidence from the Early Oligocene — 30–33 million years ago. 

Three gull-like species were described by Alphonse Milne-Edwards from the early Miocene of Saint-Gérand-le-Puy, France. 

Another fossil gull from the Middle to Late Miocene of Cherry County, Nebraska, USA, has been placed in the prehistoric genus Gaviota. 

These fossil gulls, along with undescribed Early Oligocene fossils are all tentatively assigned to the modern genus Larus. Among those of them that have been confirmed as gulls, Milne-Edwards' "Larus" elegans and "L." totanoides from the Late Oligocene/Early Miocene of southeast France have since been separated in Laricola.

Gulls are most closely related to the terns in the family Sternidae and only distantly related to auks, skimmers and distantly to waders. 

A historical name for gulls is mews, which is cognate with the German möwe, Danish måge, Swedish mås, Dutch meeuw, Norwegian måke/måse and French mouette. We still see mews blended into the lexicon of some regional dialects.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, gulls are known as t̕sik̕wi. Most folk refer to gulls from any number of species as seagulls. This name is a local custom and does not exist in the scientific literature for their official naming. Even so, it is highly probable that it was the name you learned for them growing up.

If you have been to a coastal area nearly everywhere on the planet, you have likely encountered gulls. They are the elegantly plumed but rather noisy bunch on any beach. You will recognize them both by their size and colouring. 

Gulls are typically medium to large birds, usually grey or white, often with black markings on the head or wings. They typically have harsh shrill cries and long, yellow, curved bills. Their webbed feet are perfect for navigating the uneven landscape of the foreshore when they take most of their meals. 

Most gulls are ground-nesting carnivores that take live food or scavenge opportunistically, particularly the Larus species. Live food often includes crab, clams (which they pick up, fly high and drop to crack open), fish and small birds. Gulls have unhinging jaws which allow them to consume large prey which they do with gusto. 

Their preference is to generally live along the bountiful coastal regions where they can find food with relative ease. Some prefer to live more inland and all rarely venture far out to sea, except for the kittiwakes. 

The larger species take up to four years to attain full adult plumage, but two years is typical for small gulls. Large white-headed gulls are typically long-lived birds, with a maximum age of 49 years recorded for the herring gull.

Gulls nest in large, densely packed, noisy colonies. They lay two or three speckled eggs in nests composed of vegetation. The young are precocial, born with dark mottled down and mobile upon hatching. Gulls are resourceful, inquisitive, and intelligent, the larger species in particular, demonstrating complex methods of communication and a highly developed social structure. Many gull colonies display mobbing behaviour, attacking and harassing predators and other intruders. 

Certain species have exhibited tool-use behaviour, such as the herring gull, using pieces of bread as bait with which to catch goldfish. Many species of gulls have learned to coexist successfully with humans and have thrived in human habitats. Others rely on kleptoparasitism to get their food. Gulls have been observed preying on live whales, landing on the whale as it surfaces to peck out pieces of flesh. They are keen, clever and always hungry.

CAVE BEAR: URSUS URALENSIS

This glorious and slightly terrifying skull is from a fossil cave bear, Ursus uralensis, from Pleistocene deposits in Russia.

Both the cave bear and the brown bear are thought to be descended from the Plio-Pleistocene Etruscan bear, Ursus etruscus, that lived about 5.3 Mya to 100,000 years ago. 

The last common ancestor of cave bears and brown bears lived between 1.2–1.4 Mya. The immediate precursor of the cave bear was probably Ursus deningeri, the Deninger's bear — a species restricted to Pleistocene Europe about 1.8 Mya to 100,000 years ago. 

The transition between Deninger's bear and the cave bear is given as the last interglacial, although the boundary between these forms is arbitrary, and intermediate or transitional taxa have been proposed, Ursus spelaeus deningeroides, while other authorities consider both taxa to be chronological variants of the same species.

Cave bears found in different regions vary in age, thus facilitating investigations into evolutionary trends. The three anterior premolars were gradually reduced, then disappeared, possibly in response to a largely vegetarian diet. 

In a fourth of the skulls found in the Conturines, the third premolar is still present, while more derived specimens elsewhere lack it. The last remaining premolar became conjugated with the true molars, enlarging the crown and granting it more cusps and cutting borders. This phenomenon, called molarization, improved the mastication capacities of the molars, facilitating the processing of tough vegetation. This allowed the cave bear to gain more energy for hibernation while eating less than its ancestors.

A lone Grizzly Bear / Na̱ndzi

In 2005, scientists recovered and sequenced the nuclear DNA of a cave bear that lived between 42,000 and 44,000 years ago. 

The procedure used genomic DNA extracted from one of the animal's teeth. Sequencing the DNA directly (rather than first replicating it with the polymerase chain reaction), the scientists recovered 21 cave bear genes from remains that did not yield significant amounts of DNA with traditional techniques.

This study confirmed and built on results from a previous study using mitochondrial DNA extracted from cave bear remains ranging from 20,000 to 130,000 years old. 

Both show that the cave bear was more closely related to the brown bear and polar bear than it was to the American black bear, but had split from the brown bear lineage before the distinct eastern and western brown bear lineages diversified and before the split of brown bears and polar bears. The divergence date estimate of cave bears and brown bears is about 1.2–1.4 Mya. However, a recent study showed that both species had some hybridization between them.

We are blessed to have them living amongst us today on the rugged west coast of British Columbia. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, this big fellow is na̱ndzi — a lovely, large peaceful bear.

MUSKOX: CAPRINAE

Look at this soulful fellow. He is a muskox who spends his days slowly meandering through these gorgeous fields eating his fill of nutritious plants on the open tundra. They are social animals, moving together in large herds. 

As a member of the subfamily Caprinae of the family Bovidae, the muskox is more closely related to sheep and goats than to oxen. It has been placed in its own genus, Ovibos — Latin for sheep-ox. It is one of the two largest extant members of Caprinae, along with the similarly sized takin.

While the takin and muskox were once considered possibly closely related, the takin lacks common ovibovine features, such as the muskox's specialized horn morphology, and genetic analysis shows that their lineages actually separated early in caprine evolution. 

Instead, the muskox's closest living relatives appear to be the gorals of the genus Naemorhedus, nowadays common in many countries of central and east Asia. The vague similarity between takin and muskox must therefore be considered an example of convergent evolution.

The modern muskox is the last member of a line of ovibovines that first evolved in temperate regions of Asia and adapted to a cold tundra environment late in its evolutionary history. They lived alongside our lovely Mammoths and would have competed for the same plant resources as those much larger beasts. 

Muskox ancestors with sheep-like high-positioned horns — horn cores being mostly over the plane of the frontal bones, rather than below them as in modern muskoxen — first left the temperate forests for the developing grasslands of Central Asia during the Pliocene, expanding into Siberia and the rest of northern Eurasia. 

Later migration waves of Asian ungulates, including the high-horned muskox, reached Europe and North America during the first half of the Pleistocene. The first well-known muskox, the "shrub-ox" Euceratherium, crossed to North America over an early version of the Bering Land Bridge two million years ago and prospered in the American southwest and Mexico. Euceratherium was larger yet more lightly built than modern muskoxen, resembling a giant sheep with massive horns, and preferred hilly grasslands.

A genus with intermediate horns, Soergelia, inhabited Eurasia in the early Pleistocene, from Spain to Siberia, and crossed to North America during the Irvingtonian (1.8 million years to 240,000 years ago), soon after Euceratherium. Unlike Euceratherium, which survived in America until the Pleistocene-Holocene extinction event, Soergelia was a lowland dweller that disappeared fairly early, displaced by more advanced ungulates, such as the "giant muskox" Praeovibos (literally "before Ovibos"). 

The low-horned Praeovibos was present in Europe and the Mediterranean 1.5 million years ago, colonized Alaska and the Yukon one million years ago and disappeared half a million years ago. Praeovibos was a highly adaptable animal that appears associated with cold tundra (reindeer) and temperate woodland (red deer) faunas alike. 

During the Mindel glaciation 500,000 years ago, Praeovibos was present in the Kolyma river area in eastern Siberia in association with many Ice Age megafauna that would later coexist with Ovibos, in the Kolyma itself and elsewhere, including wild horses, reindeer, woolly mammoth and stag-moose. 

It is debated, however, if Praeovibos was directly ancestral to Ovibos, or both genera descended from a common ancestor since the two occurred together during the middle Pleistocene. Defenders of ancestry from Praeovibos have proposed that Praeovibos evolved into Ovibos in one region during a period of isolation and expanded later, replacing the remaining populations of Praeovibos.

Two more Praeovibos-like genera were named in America in the 19th century, Bootherium and Symbos, which are now identified as the male and female forms of a single, sexually dimorphic species, the "woodland muskox", Bootherium bombifrons. Bootherium inhabited open woodland areas of North America during the Late Pleistocene, from Alaska to Texas and maybe even Mexico, but was most common in the Southern United States, while Ovibos replaced it in the tundra-steppe to the north, immediately south of the Laurentian ice sheet.

Modern Ovibos appeared in Germany almost one million years ago and were common in the region through the Pleistocene. Muskoxen had also reached the British Isles. Both Germany and Britain were just south of the Scandinavian ice sheet and covered in the tundra during cold periods, but Pleistocene muskoxen are also rarely recorded in more benign and wooded areas to the south like France and Green Spain, where they coexisted with temperate ungulates like red deer and aurochs. Likewise, the muskox is known to have survived in Britain during warm interglacial periods.

Today's muskoxen are descended from others believed to have migrated from Siberia to North America between 200,000 and 90,000 years ago, having previously occupied Alaska (at the time united to Siberia and isolated periodically from the rest of North America by the union of the Laurentide and Cordilleran Ice Sheets during colder periods) between 250,000 and 150,000 years ago. 

After migrating south during one of the warmer periods of the Illinoian glaciation, non-Alaskan American muskoxen would be isolated from the rest in the colder periods. The muskox was already present in its current stronghold of Banks Island 34,000 years ago, but the existence of other ice-free areas in the Canadian Arctic Archipelago at the time is disputed.

Along with the bison and the pronghorn, the muskox was one of a few species of Pleistocene megafauna in North America to survive the Pleistocene/Holocene extinction event and live to the present day. The muskox is thought to have been able to survive the last glacial period by finding ice-free areas (refugia) away from prehistoric peoples.

Fossil DNA evidence suggests that muskoxen were not only more geographically widespread during the Pleistocene, but also more genetically diverse. During that time, other populations of muskoxen lived across the Arctic, from the Ural Mountains to Greenland. By contrast, the current genetic makeup of the species is more homogenous. Climate fluctuation may have affected this shift in genetic diversity: research indicates colder periods in Earth's history are correlated with more diversity and warmer periods with more homogeneity.

ORIGINS OF THE WOOLLY MAMMOTHS

Woolly Mammoths, Mammuthus primigenius,  have always held wonder for me. These massive, hairy — and likely very smelly beasts — lived alongside us for a time. 

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 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 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 hard work to get at as much of his world was covered in ice and snow during his reign.

We first see Woolly Mammoths in northeastern Siberia dating back 700,000 years. We find them in East Asia as far back as 800,000 years ago. They arose from the massive steppe mammoths, Mammuthus trogontherii, slowly evolving traits we see in this older species to the mammoths we think of today. 

Over time, their body size shrank and their teeth and tusks evolved to take advantage of the tough vegetation available to those few animals who could chew their way through ice and snow and work these tundra grasses into a digestible form. 

The enamel plates of their cheek teeth multiplied while the enamel itself became thinner. Tusks slowly took on more of a curved to act as ploughs for the snow. 

Those smaller than their predecessors, they were still formidable. Their size offered protection against predators once full grown. Sadly for the juveniles, they offered tasty prey to big cats like Homotherium who roamed these ancient grasslands alongside them.

The Mammoths of the Steppe spread to the northern areas of Eurasia, down through Europe, into the British Isles to Spain and crossed over to populate North America via the Bering Isthmus. It was the lowered sea levels during the last Ice Age that exposed dry land between Asia and the Americas. Here in this flat, grassy treeless plain known as the Bering Land Bridge or Isthmus, animals, including humans, could migrate from Europe west into North America.

The woolly mammoth coexisted with our ancestors who made good use of their bones and tusks for tools, housing, art and food. The last of their lineage died out relatively recently on Wrangel Island until 4,000 years ago — a time when we were making our first harps and flutes in Egypt, dams, canals and stone sculptures in Sumer, using numbers for the first time and using tin to make tools.

DUGONG: SEA COW

One of the most delightful creatures to ever grace this planet is the dugong — a species of sea cow found throughout the warm latitudes of the Indian and western Pacific Oceans. 

It is one of four living species of the order Sirenia, which also includes three species of manatees — their large, fully aquatic, mostly herbivorous marine mammal cousins.

The closest living relatives of sirenians are elephants. Manatees evolved from the same land animals as elephants over 50 million years ago. 

If not for natural selection, we might have a much more diverse showing of the Sirenia as their fossil lineage shows a much more diverse group of sirenians back in the Eocene than we have today. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow, was hunted to extinction in the 18th century. 

While only one species of the dugong is alive today – a second, the Steller's sea cow only left this Earth a few years ago. Sadly, it was hunted to extinction within 27 years of its discovery – about 30 species have been recovered in the fossil record

The first appearance of sirenians in the fossil record was during the early Eocene, and by the late Eocene, sirenians had significantly diversified. Inhabitants of rivers, estuaries, and nearshore marine waters, they were able to spread rapidly.

The most primitive sirenian known to date, Prorastomus, was found in Jamaica, not the Old World; however, more recently the contemporary Sobrarbesiren has been recovered from Spain. The first known quadrupedal sirenian was Pezosiren from the early Eocene. 

The earliest known sea cows, of the families Prorastomidae and Protosirenidae, are both confined to the Eocene and were about the size of a pig, four-legged amphibious creatures. 

By the time the Eocene drew to a close, the Dugongidae had arrived; sirenians had acquired their familiar fully aquatic streamlined body with flipper-like front legs with no hind limbs, powerful tail with horizontal caudal fin, with up and down movements which move them through the water, like cetaceans.

The last of the sirenian families to appear, Trichechidae, apparently arose from early dugongids in the late Eocene or early Oligocene. The current fossil record documents all major stages in hindlimb and pelvic reduction to the extreme reduction in the modern manatee pelvis, providing an example of dramatic morphological change among fossil vertebrates.

Since sirenians first evolved, they have been herbivores, depending on seagrasses and aquatic angiosperms, tasty flowering plants of the sea, for food. To the present, almost all have remained tropical — with the notable exception of Steller's Sea Cow — marine, and angiosperm consumers. Sea cows are shallow divers with large lungs. They have heavy skeletons to help them stay submerged; the bones are pachyostotic (swollen) and osteosclerotic (dense), especially the ribs which are often found as fossils.

Eocene sirenians, like Mesozoic mammals but in contrast to other Cenozoic ones, have five instead of four premolars, giving them a 3.1.5.3 dental formula. Whether this condition is truly primitive retention in sirenians is still under debate.

Although cheek teeth are relied on for identifying species in other mammals, they do not vary to a significant degree among sirenians in their morphology but are almost always low-crowned —brachyodont — with two rows of large, rounded cusps — bunobilophodont. The most easily identifiable parts of sirenian skeletons are the skull and mandible, especially the frontal and other skull bones. With the exception of a pair of tusk-like first upper incisors present in most species, front teeth — incisors and canines — are lacking in all, except the earliest sirenians.

PSEUDOTHURMANNIA PICTETI

Pseudothurmannia is a genus of extinct cephalopods belonging to the subclass Ammonoidea and included in the family Crioceratitidae of the ammonitid superfamily Ancylocerataceae.

Ammonites have intricate and complex patterns on their shells called sutures. The suture patterns differ across species and tell us what time period the ammonite is from.

We can see from the suture patterns shown here and by comparing it to others that are similar that this fast-moving nektonic carnivore lived in the Cretaceous, from the Hauterivian to the Barremian.

Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. They used these tentacles to snare prey — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunt today.

Catching a fish with your hands is no easy feat, as I'm sure you know. Ammonites were skilled and successful hunters. They caught their prey while swimming and floating in the water column. 

Within their shells, they had a number of chambers, called septa, filled with gas or fluid that were interconnected by a wee air tube. By pushing air in or out, they were able to control their buoyancy in the water column. They lived in the last chamber of their shells, continuously building new shell material as they grew. As each new chamber was added, the squid-like body of the ammonite would move down to occupy the final outside chamber.

Shells of Pseudothurmannia can reach a diameter of about 4–12 centimetres (1.6–4.7 in). They show flat or slightly convex sides, with dense ribs and a subquadrate whorl section.

We find fossils of Pseudothurmannia in Cretaceous outcrops in Antarctica, Czechoslovakia, France, Hungary, Italy, Japan, Morocco, Spain, Russia and the United States. The specimen you see here is in the collection of the deeply awesome Manuel Peña Nieto from Córdoba, Spain and is from the Lower Cretaceous of Mallorca.

TRACKING WHALES WITH BARNACLES

We can trace the lineage of barnacles back to the Middle Cambrian. That is half a billion years of data to sift through. 

If you divide that timeline in half yet again, we begin to understand barnacles and their relationship to other sea-dwelling creatures — with a lens that reveals ancient migration patterns.

Barnacles are in the infraclass Cirripedia in the class Maxillopoda. They are marine arthropods related to crabs and lobsters. 

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. Unless scraped off, barnacles live on one single sturdy object for their entire lives — 8 to 20 years — while chowing down on tasty snacks like plankton and algae they absorb from the surrounding water.

One of the most interesting aha moments in palaeontology came from the study of 270,000 million-year-old k̕wit̕a̱'as. These sticky wee crustaceans have enabled us to trace the course of ancient whale migration. 

University of California Berkeley doctoral student Larry Taylor published some clever findings on how fossil barnacles hitched a ride on the backs of humpback and grey whales millions of years ago and used this data to reconstruct the migrations of ancient whale populations.

The barnacles record details about the whales’ yearly travels in the fossil record. 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 with 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. 

Barnacles have few predators. Their one nemesis is the whelk. It seems that catching a lifetime's ride on a passing whale would have extended their ability to feed on plankton in a variety of settings whelk-free and likely live longer than they might have cemented to something closer to the seafloor.

CONLINOCERAS TARRANTENSE

Previously Calycoceras Tarrantense, this ammonite is now called Conlinoceras tarrantense after J.P. Conlin, a famous early 20th-century fossil collector from Texas, USA.

Ammonite expert Bill Cobban used this collection to describe many Texas Cretaceous ammonites species including this species from Tarrant County, Arlington, Texas.

He was a surveyor by training and kept incredibly detailed notes on the context of his fossils.

Conlin donated his collection to the USGS and we have learned much by studying it along with other specimens from the Lone Star State. Almost a quarter of Texas is covered by Cretaceous strata, much of it fossiliferous. If we stepped back 95 million years, the world and what we now call Texas was a very different place.

95 million years ago, during the Late Cretaceous, a shallow seaway separated North America into separate eastern and western landmasses. We have a pretty complete picture in the fossil record of the western groups of species but relatively little in comparison to their cohorts in the east.

At the time this fellow was swimming our ancient seas, he was sharing the Earth with carnivorous dinosaurs, duck-billed dinosaurs, mammals, crocodilians, turtles, a variety of amphibians, prehistoric bony fish, oddly prolific sea cucumbers, various invertebrates and plants. Many of these sites are just being written up now and contain new species just being discovered.

During the Late Cretaceous Period, a shallow seaway separated North America into separate eastern and western landmasses. The Woodbine Formation in Texas preserves a rare fossil record of this time for the east, but many of these fossils are isolated and incomplete, making interpretations more difficult. Preliminary excavations at the Arlington Archosaur Site (AAS) are providing hints at a more complete ecosystem, preserving similar patterns of change to what we see in the west.

The Arlington Archosaur site contains an extraordinary diversity, abundance, and quality of fossil material, preserving one of the most complete terrestrial ecosystems known for this time period and area.

These outcrops and the fossils they contain have a lot to tell us about Late Cretaceous life in the east. Over 2200 individual specimens have been found belonging to numerous groups including carnivorous dinosaurs, duck-billed dinosaurs, crocodilians, turtles, mammals, amphibians, sharks, bony fish, invertebrates, and plants.

Many of the fossils found here represent brand new species and studying these fossils will help to establish the geographic and environmental forces that shaped Cretaceous ecosystems in North America by providing a necessary comparison to the fossil record of the west.

FOSSILS, TEXTILES AND URINE

Yorkshire Coast

You may recall the eight-metre Type Specimen of the ichthyosaur, Temnodontosaurus crassimanus, found in an alum quarry in Yorkshire, northern England.

The Yorkshire Museum was given this important ichthyosaur fossil back in 1857 when alum production was still a necessary staple of the textile industry. Without that industry, many wonderful specimens would likely never have been unearthed.

These quarries are an interesting bit of British history as they helped shape the Yorkshire Coast, created an entirely new industry and gave us more than a fixative for dyes. With them came the discovery of many remarkable fossil specimens and, oddly, local employment in the collection of urine.

In the 16th century, alum was essential in the textile industry as a fixative for dyes. 

By the first half of the 16th century, the clothing of the Low Countries, German states, and Scandinavia had developed in a different direction than that of England, France, and Italy, although all absorbed the sobering and formal influence of Spanish dress after the mid-1520s. Those fashions held true until the Inquisition when religious persecution, politics and fashion underwent a much-needed overhaul to something lighter.

Fashion in Medieval Livonia (1521): Albrecht Dürer

Elaborate slashing was popular, especially in Germany. In the depiction you see here, an artist pokes a bit of fun at Germanic fashion from the time. Bobbin lace arose from passementerie in the mid-16th century in Flanders, the Flemish Dutch-speaking northern portion of Belgium. Black was increasingly worn for the most formal occasions.

This century saw the rise of the ruff, which grew from a mere ruffle at the neckline to immense, slightly silly, cartwheel shapes. They adorned the necklines of the ultra-wealthy and uber-stylish men and women of the age.

At their most extravagant, ruffs required wire supports and were made of fine Italian reticella, a cutwork linen lace.

16th Century Fashion / Ruff Collars and Finery

In contrast to all that ruff, lace and cutwork linen, folk needed dyed fabrics. And to fix those dyes, they needed Alum. For a time, Italy was the source of that alum.

The Pope held a tidy monopoly on the industry, supplying both alum and the best dyes. He also did a nice trade in the colourful and rare pigments for painting. And for a time, all was well with dandy's strutting their finery to the local fops in Britain.

All that changed during the Reformation. Great Britain, heathens as they were, were cut-off from their Papal source and found themselves needing to fend for themselves.

The good Thomas Challoner took up the charge and set up Britain's first Alum works in Guisborough. Challoner looked to paleontology for inspiration. Noticing that the fossils found on the Yorkshire coast were very similar to those found in the Alum quarries in Europe, he hatched a plan to set-up an alum industry on home soil. As the industry grew, sites along the coast were favoured as access to the shales and subsequent transportation was much easier.

Alum House, Photo: Joyce Dobson and Keith Bowers

Alum was extracted from quarried shales through a large scale and complicated process which took months to complete. The process involved extracting then burning huge piles of shale for 9 months, before transferring it to leaching pits to extract an aluminum sulphate liquor. This was sent along channels to the alum works where human urine was added.

At the peak of alum production, the industry required 200 tonnes of urine every year. That's the equivalent of all the potty visits of more than 1,000 people. Yes, strange but true.

The steady demand was hard to keep up with and urine became an imported resource from markets as far away as London and Newcastle upon Tyne in the northeast of England. Wooden buckets were left on street corners for folk to do their business then carted back to the south to complete the alum extraction process. The urine and alum would be mixed into a thick liquid. Once mixed, the aromatic slosh was left to settle and then the alum crystals were removed.

I'm not sure if this is a folktale or plain truth, but as the story goes, one knows when the optimum amount of alum had been extracted as you can pop an egg in the bucket and it floats on its own.

Alum House. Photo: Ann Wedgewood and Keith Bowers

The last Alum works on the Yorkshire Coast closed in 1871. This was due to the invention of manufacturing synthetic alum in 1855, then subsequently the creation of aniline dyes that contained their own fixative.

There are many sites along the Yorkshire Coast which bear evidence of the alum industry. These include Loftus Alum Quarries where the cliff profile is drastically changed by extraction and huge shale tips remain.

Further South are the Ravenscar Alum Works, which are well preserved and enable visitors to visualize the processes which took place. The photos you see here are of Alum House at Hummersea. The first shows the ruin of Alum House printed on a postcard from 1906. The second (bottom) image shows the same ruin from on high with Cattersty Point in the background.

The good folk at the National Trust in Swindon are to thank for much of the background shared here. If you'd like to learn more about the Yorkshire area or donate to a very worthy charity, follow their link below.

Reference: https://www.nationaltrust.org.uk/yorkshire-coast/features/how-alum-shaped-the-yorkshire-coast