FOSSILS AND FAUNA OF MADAGASGAR

Aioloceras besairiei (Collingnon, 1949)

A stunning example of the internal suturing with calcite infill in this sliced Aioloceras besairiei (Collingnon, 1949) ammonite from the Upper Cretaceous (Lower Albian) Boeny region of Madagascar. 

This island country is 400 kilometres off the coast of East Africa in the Indian Ocean and a wonderful place to explore off the beaten track.

Madagascar has some of the most spectacular of all the fossil specimens I have ever seen. This beauty is no exception. The shell has a generally small umbilicus, arched to acute venter, and typically at some growth stage, falcoid ribs that spring in pairs from umbilical tubercles, usually disappearing on the outer whorls. I had originally had this specimen marked as a Cleoniceras besairiei, except Cleoniceras and Grycia are not present in Madagascar. 

This lovely, seen in cross-section, is now far from home and in the collection of a wonderful friend. It is an especially lovely example of the ammonite, Aioloceras besairiei, making it a beudanticeratinae. Cleoniceras and Grycia are the boreal genera. If you'd like to see (or argue) the rationale on the name, consider reading Riccardi and Medina's riveting work from back in 2002, or Collingnon from 1949.

The beauty you see here measures in at a whopping 22 cm, so quite a handful. This specimen is from the youngest or uppermost subdivision of the Lower Cretaceous. I'd originally thought this locality was older, but dating reveals it to be from the Lower Albian, so approximately 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma.

Aioloceras are found in the Cretaceous of Madagascar at geo coordinates 16.5° S, 45.9° E: paleo-coordinates 40.5° S, 29.3° E.; and in four localities in South Africa: at locality 36, near the Mzinene River at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E. 

We find them near the Mziene River, at a second locality north of Hluhluwe where the Mzinene Formation overlies the Aptian-Albian Makatini Formation at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E; and at Haughton Z18, on the Pongola River in the Albian III, Tegoceras mosense beds at 27.3° S, 32.2° E: paleo-coordinates 48.0° S, 7.8° E.

If you happen to be trekking to Madagascar, know that it's big. It’s 592,800 square kilometres (or  226,917 square miles), making it the fourth-largest island on the planet — bigger than Spain, Thailand, Sweden and Germany. The island has an interesting geologic history.

Although there has been a geological survey, which was active extending back well into French colonial times, in the non-French-speaking world our geological understanding of the island is still a bit of a mystery. 

Plate tectonic theory had its beginnings in 1915 when Alfred Wegener proposed his theory of "continental drift." 

Wegener proposed that the continents ploughed through the crust of ocean basins, which would explain why the outlines of many coastlines (like South America and Africa) look like they fit together like a puzzle. Half a century after Wegener there is still no agreement as to whether in continental reconstructions Madagascar should be placed adjacent to the Tanzanian coast to the north (e.g., McElhinny and Embleton,1976), against the Mozambique-Natal coast (Flores 1970), or basically left where it is (Kent 1974, Nairn 1978).

There have been few attempts apart from McKinley’s (1960) comparison of the Karoo succession of southwestern Tanzania with that of Madagascar to follow the famous geological precept of “going to sea.” One critical reason is that although there may be a bibliography of several thousand items dealing with Madagascan geology as Besairie (1971) claims, they are items not generally available to the general public. The vital information gained of the geology of the offshore area by post-World War II petroleum exploration has remained largely proprietary. 

Without this data to draw upon, our understanding remains incomplete. I don't actually mind a bit of a mystery here. It is interesting to speculate on how these geologic puzzle pieces fit together and wait for the big reveal. Still, we have good old Besairie from his 1971, Geologie de Madagascar, and a later précis (Besairie, 1973).

We do know that Madagascar was carved off from the African-South American landmass early on. The prehistoric breakup of the supercontinent Gondwana separated the Madagascar–Antarctica–India landmass from the Africa–South America landmass around 135 million years ago. Madagascar later split from India about 88 million years ago, during the Late Cretaceous, so the native plants and animals on the island evolved in relative isolation. 

It is a green and lush island country with more than its fair share of excellent fossil exposures. Along the length of the eastern coast runs a narrow and steep escarpment containing much of the island's remaining tropical lowland forest. If you could look beneath this lush canopy, you'd see rocks of the Precambrian age stretching from the east coast all the way to the centre of the island. The western edge is made up of sedimentary rock from the Carboniferous to the Quaternary.

Red-Tailed Lemurs, Waiwai & Hedgehog

Madagascar is a biodiversity hotspot. Just as Darwin's finches on the Galápagos were isolated, evolving into distinct species (hello, adaptive radiation), over 90% of the wildlife from Madagascar is found nowhere else. 

The island's diverse ecosystems, like so many on this planet, are threatened by Earth's most deadly species, homo sapien sapiens. 

We arrived back in 490 CE and have been chopping down trees and eating our way through the island's tastier populations ever since. Still, they have cuties like this Red-Tailed Lemur. Awe, right?

Today, beautiful outcrops of wonderfully preserved fossil marine fauna hold appeal for me. The material you see from Madagascar is distinctive — and prolific.

Culturally, you'll see a French influence permeating the language, architecture and legal process. There is a part of me that pictures these lovely Lemurs chatting away in French. "Ah, la vache! Regarde le beau fossile, Hérissonne!"

We see the French influence because good 'ol France invaded sleepy Madagascar back in 1883, during the first Franco-Hova War. Malagasy (the local Madagascarian residents) were enlisted as troops, fighting for France in World War I.  During the Second World War, the island was the site of the Battle of Madagascar between the Vichy government and the British. By then, the Malagasy had had quite enough of colonization and after many hiccuping attempts, reached full independence in 1960. Colonization had ended but the tourist barrage had just begun. You can't stop progress.

If you're interested in learning more about this species, check out the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). R.C. Moore (ed). Geological Soc of America and Univ. Kansas Press (1957), p L394. Or head over to look at the 2002 paper from Riccardi and Medina. 2002. Riccardi, A., C. & Medina, F., A. The Beudanticeratinae and Cleoniceratinae (Ammonitina) from the Lower Albian of Patagonia in Revue de Paléobiologie - 21(1) - Muséum d’Histoire Naturelle de la ville de Genève, p 313-314 (=Aioloceras besairiei (COLLIGNON, 1949). You have Bertrand Matrion to thank for the naming correction. Good to have friends in geeky places!

Collignon, M., 1933, Fossiles cenomaniens d’Antmahavelona (Province d’ Analalave, Madagascar), Ann. Geol. Serv. Min. Madagascar, III, 1934 Les Cephalopods du Trias inferieur de Madagascar, Ann. Paleont. XXII 3 and 4, XXII 1.

Besairie, H., 1971, Geologie de Madagascar, 1. Les terrains sedimentaires, Ann. Geol. Madagascar, 35, p. 463.

J. Boast A. and E. M. Nairn collaborated on a chapter in An Outline of the Geology of Madagascar, that is very readable and cites most of the available geologic research papers. It is an excellent place to begin a paleo exploration of the island.

If you happen to parle français, check out: Madagascar ammonites: http://www.ammonites.fr/Geo/Madagascar.htm

URSUS NURSERY: BLACK BEARS / TLA'YI

Look at how this protective mamma bear holds her cub in her arms to give him a bit of a wash. 

Her gentle maternal care is truly touching. This mamma has spent late Autumn to Spring in a cave, having birthed them while still hibernation and staying in the den to feed them on her milk.

Black bear cubs stay with their mamma for the first one to three years of their lives while she protects them and teaches them how to thrive in the wild using their keen sense of smell, hearing, vision and strength. Once they are old enough, they will head off into the forest to live solo until they are ready to mate and start a family of their own. 

Mating is a summer affair with bears socializing shoulder to shoulder with potential mates. Once they have mated, black bears head off on their own again to forage and put on weight for their winter hibernation. If the black bear lives in the northern extent of their range, hibernation lasts longer — they will stay in their dens for seven to eight months longer than their southern counterparts. For those that enjoy the warmer climes in the south, hibernation is shorter. If food is available year-round, the bears do not hibernate at all.

The American black bear, Ursus americanus, is native to North America and found in Canada and the United States. 

They are the most common and widely distributed of the three bear species found in Canada. 

There are roughly 650,000 roaming our forests, swamps and streams — meaning there is a good chance of running into them if you spend any amount of time in the wild. 

Full-grown, these fuzzy monkeys will be able to run 48 kilometres (30 miles)  an hour and smell food up to 32 kilometres (20 miles) away.

With their excellent hearing, black bears usually know you are near well before you realize the same and generally take care to avoid you. Those that come in contact with humans often tend to want to check our garbage and hiking supplies for tasty snacks — hey, a free meal is a free meal.    

In British Columbia, we share our province with nearly half of all black bears and grizzly bears that reside in Canada. The 120,000 - 150,000 black bears who live in the province keep our Conservation Officers busy. They account for 14,000 - 25,000 of the calls the service receives each year. Most of those calls centre around their curiosity for the tasty smells emanating from our garbage. They are omnivores with vegetation making up 80-85% of their diet, but they are flexible around that — berries and seeds, salmon or Doritos — bears eat it all. 

And, as with all wild animals, diet is regional. In Labrador, the local black bear population lives mostly on caribou, rodents and voles. In the Pacific Northwest, salmon and other fish form a large part of the protein in their diet versus the bees, yellow jackets and honey others prefer. The braver of their number have been known to hunt elk, deer and moose calves — and a few showy bears have taken on adults of these large mammals. 

Bears hold a special place within our culture and in First Nation mythology in particular — celebrated in art, dance and song. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, the word for black bear is t̕ła'yi — mother is a̱bas and łaxwa̱lap̓a means to love each other. 

Kermode or Spirit Bear, Ursus americanus kermodei

From the photos here you can see that black bears are not always black —  ranging in colour from cinnamon to brown, tan, blonde, red — and even white. 

The Kermode or Spirit Bear, Ursus americanus kermodei, a subspecies of black bear found only in British Columbia — and our official provincial mammal — is a distinctive creamy white. 

They are not albinos, their colouring stems from a recessive mutant gene — meaning that if they receive two copies it triggers a single, nonsynonymous nucleotide substitution that halts all melanin production. Well, not all. They have pigmented eyes and skin but no colour in their fur. The white colour is an advantage when you are hunting salmon by day. Salmon will shy away from their black cousins knowing their intention is to enjoy them as a tasty snack. 

Spirit Bears live in the Great Bear Rainforest on British Columbia's north and central coast alongside the Kitasoo/Xai’xais First Nation who call the Kermode moskgm’ol or white bear.

The Kitasoo/Xai’xais have a legend that tells of Goo-wee, Raven making one in every ten black bears white to remind us of the time glaciers blanketed the land then slowly retreated — their thaw giving rise to the bounty we harvest today.  

Black bears of any colour are a wee bit smaller than their brown bear or grizzly bear cousins, with males weighing in at 45 to 400 kilograms (100 to 900 pounds) and females ranging from 38 to 225 kilograms (85 to 500 pounds). 

Small by relative standards but still very large animals. And they are long-lived or at least can be. Bears in captivity can live up to 30 years but those who dwell in our forests tend to live half as long or less from a mixture of local hazards and humans. 

Reference: Wild Safe BC: https://wildsafebc.com/species/black-bear/

FROM FISH TO TETRAPODS: ELPISTOSTEGE WATSONI

Elpistostege watsoni

In the late 1930s, our understanding of the transition of fish to tetrapods — and the eventual jump to modern vertebrates — took an unexpected leap forward. The evolutionary a'ha came from a single partial fossil skull found on the shores of a riverbank in Eastern Canada. 

Meet the Stegocephalian, Elpistostege watsoni, an extinct genus of finned tetrapodomorphs that lived during the Late Givetian to Early Frasnian of the Late Devonian — 382 million years ago. 

Elpistostege watsoni — perhaps the sister taxon of all other tetrapods — was first described in 1938 by British palaeontologist and elected Fellow of the Royal Society of London, Thomas Stanley Westoll. Westoll's research interests were wide-ranging. He was a vertebrate palaeontologist and geologist best known for his innovative work on Palaeozoic fishes and their relationships with tetrapods. 

As a specialist in early fish, Westoll was asked to interpret that single partial skull roof discovered at the Escuminac Formation in Quebec, Canada. His findings and subsequent publication named Elpistostege watsoni and helped us to better understand the evolution of fishes to tetrapods — four-limbed vertebrates — one of the most important transformations in vertebrate evolution. 

Hypotheses of tetrapod origins rely heavily on the anatomy of but a few tetrapod-like fish fossils from the Middle and Late Devonian, 393–359 million years ago. These taxa — known as elpistostegalians — include Panderichthys, Elpistostege and Tiktaalik — none of which had yet to reveal the complete skeletal anatomy of the pectoral fin. 

Elpistostege watsoni

None until 2010 that is, when a complete 1.57-metre-long articulated specimen was found and described by Richard Cloutier et al. in 2020. 

The specimen helped us to understand the origin of the vertebrate hand. Stripped from its encasing stone, it revealed a set of paired fins of Elpistostege containing bones homologous to the phalanges (finger bones) of modern tetrapods and is the most basal tetrapodomorph known to possess them. 

Once the phalanges were uncovered, prep work began on the fins. The fins were covered in wee scales and lepidotrichia (fin rays). The work was tiresome, taking more than 2,700 hours of preparation but the results were thrilling. 

Origin of the Vertebrate Hand

We could now clearly see that the skeleton of the pectoral fin has four proximodistal rows of radials — two of which include branched carpals — as well as two distal rows organized as digits and putative digits. 

Despite this skeletal pattern — which represents the most tetrapod-like arrangement of bones found in a pectoral fin to date blurring the line between fish and land vertebrates — the fin retained lepidotrichia (those wee fin rays) distal to the radials. 

This arrangement confirmed an age-old question — showing us for the first time that the origin of phalanges preceded the loss of fin rays, not the other way around.

E. watsoni is very closely related to Tiktaalik roseae found in 2004 in the Canadian Arctic — a tetrapodomorpha species also known as a Choanata. These were advanced forms transitional between fish and the early labyrinthodonts playfully referred to as fishapods — half-fish, half-tetrapod in appearance and limb morphology. 

Up to that point, the relationship of limbed vertebrates (tetrapods) to lobe-finned fish (sarcopterygians) was well known, but the origin of major tetrapod features remained obscure for lack of fossils that document the sequence of evolutionary changes — until Tiktaalik. While Tiktaalik is technically a fish, this fellow is as far from fish-like you can be and still be a card-carrying member of the group. 

Tiktaalik roseae

Complete with scales and gills, this proto-fish lacked the conical head we see in modern fish but had a rather flattened triangular head more like that of a crocodile. 

Tiktaalik had scales on its back and fins with fin webbing but like early land-living animals, it had a distinctive flat head and neck. He was a brawny brute. The shape of his skull and shoulder look part fish and part amphibian.

The watershed moment came as Tiktaalik was prepped. Inside Tiktaalik's fins, we find bones that correspond to the upper arm, forearm and even parts of the wrist — all inside a fin with webbing — remarkable! 

Its fins have thin ray bones for paddling like most fish, but with brawny interior bones that gave Tiktaalik the ability to prop itself up, using his limbs for support. I picture him propped up on one paddle saying, "how you doing?" 

Six years after Tiktaalik was discovered by Neil Shubin and team in the ice-covered tundra of the Canadian Arctic on southern Ellesmere Island, a team working the outcrops at Miguasha on the Gaspé Peninsula discovered the only fully specimen of E. watsoni found to date — greatly increasing our knowledge of this finned tantalizingly transitional tetrapodomorph. 

E. watsoni fossils are rare — this was the fourth specimen collected in over 130 years of hunting. Charmingly, the specimen was right on our doorstop — extracted but a few feet away from the main stairs descending onto the beach of Miguasha National Park. 

L'nu Mi’gmaq First Nations of the Gespe’gewa’gi Region

Miguasha is nestled in the Gaspésie or Gespe’gewa’gi region of Canada — home to the Mi’gmaq First Nations who self-refer as L’nu or Lnu. The word Mi’gmaq or Mi’kmaq means the family or my allies/friends in Mi'kmaw, their native tongue (and soon to be Nova Scotia's provincial first language). They are the people of the sea and the original inhabitants of Atlantic Canada having lived here for more than 10,000 years. 

The L'nu were the first First Nation people to establish contact and trade with European explorers in the 16th and 17th centuries — and perhaps the Norse as early as the turn of the Millenium. Sailing vessels filled with French, British, Scottish, Irish and others arrived one by one to lay claim to the region — settling and fighting over the land. As each group rolled out their machinations of discovery, tensions turned to an all-out war with the British and French going head to head. I'll spare you the sordid details but for everyone caught in the crossfire, it went poorly.

North America Map 1775 (Click to Enlarge)

Cut to 1760, the British tipped the balance with their win at the Battle of the Restigouche, the last naval battle between France and England for possession of the North American continent — Turtle Island. 

The bittersweet British victory sparked the American War of Independence. 

For the next twenty years, the L'nu would witness and become embroiled in yet another war for these lands, their lands — first as bystanders, then as American allies, then intimidated into submission by the British Royal Navy with a show of force by way of a thirty-four gun man-of-war, encouraging L'nu compliance — finally culminating in an end to the hostilities with the 1783 Treaty of Paris. 

The peace accord held no provisions for the L'nu, Métis and First Nations impacted. None of these newcomers was Mi'kmaq — neither friends nor allies.

It was to this area some sixty years later that the newly formed Geological Survey of Canada (GSC) began exploring and mapping the newly formed United Province of Canada. Geologists in the New Brunswick Geology Branch traipsed through the rugged countryside that would become a Canadian province in 1867. 

It was on one of these expeditions that the Miguasha fossil outcrops were discovered. They, too, would transform in time to become Miguasha National Park or Parc de Miguasha, but at first, they were simply the promising sedimentary exposures on the hillside across the water —  a treasure trove of  Late Devonian fauna waiting to be discovered.

In the summer of 1842, Abraham Gesner, New Brunswick’s first Provincial Geologist, crossed the northern part of the region exploring for coal. Well, mostly looking for coal. Gesner also had a keen eye for fossils and his trip to the Gaspé Peninsula came fast on the heels of a jaunt along the rocky beaches of Chignecto Bay at the head of the Bay of Fundy and home to the standing fossil trees of the Joggins Fossil Cliffs. 

Passionate about geology and chemistry, he is perhaps most famous for his invention of the process to distil the combustible hydrocarbon kerosene from coal oil — a subject on which his long walks exploring a budding Canada gave him a great deal of time to consider. We have Gesner to thank for the modern petroleum industry. He filed many patents for clever ways to distil the soft tar-like coal or bitumen still in use today.

He was skilled in a broad range of scientific disciplines — being a geologist, palaeontologist, physician, chemist, anatomist and naturalist — a brass tacks geek to his core. Gesner explored the coal exposures and fossil outcrops across the famed area that witnessed the region become part of England and not France — and no longer L'nu.

Following the Restigouche River in New Brunswick through the Dalhousie region, Gesner navigated through the estuary to reach the southern coast of the Gaspé Peninsula into what would become the southeastern coast of Quebec to get a better look at the cliffs across the water. He was the first geologist to lay eyes on the Escuminac Formation and its fossils.

In his 1843 report to the Geologic Survey, he wrote, “...I found the shore lined with a coarse conglomerate. Farther eastward the rocks are light blue sandstones and shales, containing the remains of vegetables. (...) In these sandstone and shales, I found the remains of fish and a small species of tortoise with fossil foot-marks.”

We now know that this little tortoise was the famous Bothriolepis, an antiarch placoderm fish. It was also the first formal mention of the Miguasha fauna in our scientific literature. Despite the circulation of his report, Gesner’s discovery was all but ignored — the cliffs and their fossil bounty abandoned for decades to come. Geologists like Ells, Foord and Weston, and the research of Whiteaves and Dawson, would eventually follow in Gesner's footsteps.

North America Map 1866 (Click to Enlarge)

Over the past 180 years, this Devonian site has yielded a wonderfully diverse aquatic assemblage from the Age of Fishes — five of the six fossil fish groups associated with the Devonian including exceptionally well-preserved fossil specimens of the lobe-finned fishes. 

This is exciting as it is the lobe-finned fishes — the sarcopterygians — that gave rise to the first four-legged, air-breathing terrestrial vertebrates – the tetrapods. 

Fossil specimens from Miguasha include twenty species of lower vertebrates — anaspids, osteostra-cans, placoderms, acanthodians, actinopterygians and sarcopterygians — plus a limited invertebrate assemblage, along with terrestrial plants, scorpions and millipedes.

Originally interpreted as a freshwater lacustrine environment, recent paleontological, taphonomic, sedimentological and geochemical evidence corroborates a brackish estuarine setting — and definitely not the deep waters of the sea. This is important because the species that gave rise to our land-living animals began life in shallow streams and lakes. It tells us a bit about how our dear Elpistostege watsoni liked to live — preferring to lollygag in cool river waters where seawater mixed with fresh. Not fully freshwater, but a wee bit of salinity to add flavour.  

• Photos: Elpistostege watsoni (Westoll, 1938 ), Upper Devonian (Frasnian), Escuminac formation, Parc de Miguasha, Baie des Chaleurs, Gaspé, Québec, Canada. John Fam, VanPS
• Origin of the Vertebrate Hand Illustration, https://www.nature.com/articles/s41586-020-2100-8
• Tiktaalik Illustration: By Obsidian Soul - Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=47401797

References & further reading:

• From Water to Land: https://www.miguasha.ca/mig-en/the_first_discoveries.php
• UNESCO Miguasha National Park: https://whc.unesco.org/en/list/686/
• Office of L'nu Affairs: https://novascotia.ca/abor/aboriginal-people/
• Cloutier, R., Clement, A.M., Lee, M.S.Y. et al. Elpistostege and the origin of the vertebrate hand. Nature 579, 549–554 (2020). https://doi.org/10.1038/s41586-020-2100-8
• Daeschler, E. B., Shubin, N. H. & Jenkins, F. A. Jr. A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. Nature 440, 757–763 (2006).
• Shubin, Neil. Your Inner Fish: A Journey into the 3.5 Billion History of the Human Body.
• Evidence for European presence in the Americas in AD 1021: https://www.nature.com/articles/s41586-021-03972-8