Tuesday, 31 August 2021

AIOLOCERAS BESAIRIEI: VIPS COLLECTION

Aioloceras besairiei (Collingnon, 1949)
Beauty is a stimulant that is administered through the eyes.

And just look at this beauty. This gorgeous burnt orange and creamy visual feast is the ammonite Aioloceras besairiei (Collingnon, 1949) from the Upper Cretaceous (Lower Albian) Boeny region of Madagascar. 

This is specimen #00783B in the collections of the Vancouver Palaeontological Society, (VIPS). The chambers have a wonderful calcite filling best viewed by carefully slicing these specimens in two. 

There is a small imperfection near the centre that renders this ammonite its signature mark of perfection. This lovely is in my care as a study specimen. 

Madagascar is an island country is about 400 kilometres off the coast of East Africa in the Indian Ocean and a wonderful place to explore off the beaten track. Exotic, beautiful and geologically interesting — it remains high on my bucket list to explore. 

Madagascar has some of the most pleasing of all the fossil specimens I have ever seen. This beauty is no exception. The shell has a generally small umbilicus, arched to acute centre and falcoid ribs that spring in pairs from the umbilical tubercles then disappear on the outer whorls. Take that magical body plan with its pleasing symmetry and add an infilling with spectacular calcite — spectacular! 

It is rightfully Aioloceras besairiei — and correctly labelled as such by the VIPS — but some specimens I have looked at earlier were marked as a Cleoniceras besairiei. This is impossible, of course, as Cleoniceras and Grycia are not present in Madagascar. This lovely, seen in cross-section, is now far from home and in my collection to enjoy for a time before returning to Courtenay on Vancouver Island. 

Aioloceras besairiei are within beudanticeratinae. Cleoniceras and Grycia are the boreal genera. If you would 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 23 cm. It hails from the youngest or uppermost subdivision of the Lower Cretaceous. I had originally thought this locality was older, but dating reveals it to be from the Lower Albian, approximately 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma. This locality produces ammonites that are beyond measure in their singular beauty. 

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 is 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. So, enjoy your time and wear comfortable shoes. 

If you are 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

Sunday, 29 August 2021

BLUE DRAGON SEA SLUG

This otherwordly fellow, straight out of a novel, is Glaucus atlanticus — the Blue Dragon Sea Slug. And what an amazing wee little dragon this is. Folk sometimes refer to them as sea swallow, blue angel, blue glaucus, dragon slug, blue dragon, blue sea slug and blue ocean slug. 

By any name, they are a very pleasing addition to our planet. Glaucus atlanticus are a species of small, blue sea slug, a pelagic aeolid nudibranch — a shell-less gastropod mollusc in the family Glaucidae.

Nudibranchs likely date back as far as the Early Jurassic, some180 million years ago. This was around the time that the supercontinent of Pangea was breaking apart to form the modern continents and the Atlantic and Indian Oceans. The date is an estimate built upon the evolutionary lineages of their closest relatives, in part because the soft-bodied nature of nudibranchs means they do not fossilize well.

These sea slugs are pelagic — they float upside down by using the surface tension of the water to stay up near the surface where they drift along, carried by the winds and ocean currents. Glaucus atlanticus makes use of countershading: the blue side of their body faces upwards, blending in with the blue of the water. The silver/grey side of the sea slugs faces downwards, blending in with the sunlight reflecting on the ocean's surface when viewed facing upwards underwater, helping them avoid becoming a tasty snack.

Glaucus atlanticus feed on other pelagic creatures, including the Portuguese man o' war and other venomous siphonophores. This sea slug stores stinging nematocysts from the siphonophores within its own tissues as a defence against predators. Humans handling the slug may receive a very painful and potentially dangerous sting. Good on you little Dragon!

Saturday, 28 August 2021

SERENE SIRENIA

This adorable aquatic vacuum is a dugong. I had always grouped the dugongs and manatees together. There are slight differences between these two but both belong to the order Sirenia. 

They shared a cousin in the Steller's sea cow, Hydrodamalis gigas, but that piece of their lineage was hunted to extinction by our species in the 18th century. 

Dugongs have tail flukes with pointed tips — similar to whales — and manatees have paddle-shaped tails, similar to a Canadian Beaver.

Both of these lovelies from the order Sirenia went from terrestrial to marine, taking to the water in search of more prosperous pastures, as it were. 

We find dugongs today in waters near northern Australia and parts of the Indian and Pacific Oceans. 

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

They favour locations where seagrass, their food of choice, grows plentiful and they eat it roots and all. While seagrass low in fibre, high in nitrogen, and easily digestible is preferred, dugongs will also dine on lower grade seagrass, algae, and invertebrates should the opportunity arise. They have been known to eat jellyfish, sea squirts, and shellfish over the course of their long lives. 

Some of the oldest dugongs have been known to live 70+ years, which is another statistic I find surprising. They are large, passive, have poor eyesight, and look pretty tasty floating in the water; a defenceless floating buffet. Their population is in decline and yet they live on.

Friday, 27 August 2021

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

Wednesday, 25 August 2021

SHORE CRAB: CARCINUS MAENAS / KU'MIS

European Green Shore Crab / Carcinus maenas
The adaptable European Green Shore Crab, Carcinus maenas, lives in a wide range of environments from fully marine to brackish estuaries.

In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, this brave fellow is ḵ̓u'mis — and in Norwegian, he is called krabbe.

They make a living off the seafloor, dining on worms, molluscs, small crustaceans and any number of bits and pieces that fall their way.

Shore Crabs are euryhaline, meaning they can tolerate a wide range of salinities (4 to 52 %), and survive in temperatures of zero to 30 °C (32 to 86 °F). This adaptability gives them a very wide range and competitive edge. This fellow is from the chilly waters of central Norway. The ability to eat pretty near anything and survive in extremely cold climates means he'll do quite well beneath the ice this winter.

Tuesday, 24 August 2021

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.

Sunday, 22 August 2021

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.

Saturday, 21 August 2021

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.

Friday, 20 August 2021

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.

Thursday, 19 August 2021

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.

Wednesday, 18 August 2021

TITANITES: THE FERNIE AMMONITE

Titanites occidentalis, Fernie Ammonite
The Fernie ammonite, Titanites occidentalis, from outcrops on Coal Mountain near Fernie, British Columbia, Canada. 

This beauty is the remains of a carnivorous cephalopod within the family Dorsoplanitidae that lived and died in a shallow sea some 150 million years ago.

If you would like to get off the beaten track and hike up to see this ancient beauty, you will want to head to the town of Fernie in British Columbia close to the Alberta border. 

There was some active logging along the hillside in 2021, so if you are looking at older directions on how to get to the site be mindful that many of the trailheads have been altered and a fair bit of bushwhacking will be necessary to get to the fossil site proper. That being said, the loggers did give the ammonite a wide berth and have left it intact.

Driving to the trail base is along an easy access road just east of town along Fernie Coal Road. There are some nice exposures of Cretaceous plant material on the north side (left-hand side) of the road as you head from Fernie towards Coal Creek. I recently drove up to Fernie to look at Cretaceous plant material and locate the access point to the now infamous Late Jurassic (Tithonian) Titanites (S.S. Buckman, 1921) site. While the drive out of town is on an easy, well-maintained road, the slog up to the ammonite site is a steep 3-hour push.

Fernie, British Columbia, Canada
The first Titanites occidentalis was about one-third the size and was incorrectly identified as Lytoceras, a fast-moving nektonic carnivore. The specimen you see here is significantly larger at 1.4 metres (about four and a half feet) and rare in North America. 

Titanites occidentalis, the Western Giant, is the second known specimen of this extinct fossil species. The first was discovered in 1947 in nearby Coal Creek by a British Columbia Geophysical Society mapping team. When they first discovered this marine fossil high up on the hillside, they could not believe their eyes — both because it is clearly marine at the top of a mountain and the sheer size of this ancient beauty.

In the summer of 1947, a field crew was mapping coal outcrops for the BC Geological Survey east of Fernie. One of the students reported finding “a fossil truck tire.” Fair enough. The similarity of size and optics are pretty close to your average Goodridge. 

A few years later, GSC Paleontologist Hans Frebold described and named the fossil Titanites occidentalis after the large Jurassic ammonites from Dorset, England. The name comes from Greek mythology. Tithonus, as you may recall, was the Prince of Troy. He fell in love with Eos, the Greek Goddess of the Dawn. Eos begged Zeus to make her mortal lover immortal. Zeus granted her wish but did not grant Tithonus eternal youth. He did indeed live forever — ageing hideously. Ah, Zeus, you old trickster. It is a clever play on time placement. Dawn is the beginning of the day and the Tithonian being the latest age of the Late Jurassic. Clever Hans!

HIKING TO THE FERNIE AMMONITE

From the town of Fernie, British Columbia, head east along Coal Creek Road towards Coal Creek. The site is 3.81 km from the base of Coal Creek Road to the trailhead as the crow flies. I have mapped it here for you in yellow and added the wee purple GPS marker for the ammonite site proper. There is a nice, dark grey to black roadcut exposure of Cretaceous plants on the north side of the dirt road that is your cue to pull over and park.  

You access what is left of the trailhead on the south side of the road. You will need to cross the creek to begin your ascent. There is no easy way across the creek and you'll want to tackle this one with a friend when the water level is low. 

The beginning of the trail is not clear but a bit of searching will reveal the trailhead with its telltale signs of previous hikers. This is a 1-2 hour moderate 6.3-kilometre hike up & back bushwhacking through scrub and fallen trees. Heading up, you will make about a 246-metre elevation gain. You will likely not have a cellular signal up here but if you download the Google Map to your mobile, you will have GPS to guide you. The area has been recently logged so much of the original trail has been destroyed. There may now be easier vehicle access up the logging roads but I have not driven them since the logging and new road construction.

If you are coming in from out of town, the closest airport is Cranbrook. Then it is about an hour and change to Fernie and another 15-minutes or so to park near the site.

You will want to leave your hammers with your vehicle (no need to carry the weight) as this site is best enjoyed with a camera. 

This is a site you will want to wear hiking boots to access. Know that these will get wet as you cross the creek. 

If you would like to see the ammonite but are not keen on the hike, a cast has been made by fossil preparator Rod Bartlett is on display at the Courtenay Museum in Courtenay, Vancouver Island, Canada. 

As your feet move up the hillside, you can imagine this land 10,000 years ago, rising above great glaciers. Where footfalls trace the steps of those that came before you. This land has been home to the Ktunaxa or Kukin ʔamakis First Nations whose oral history have them living here since time immemorial. Like them, take only what you need and no more than the land offers — packing out anything that you packed in. 

Fernie Ammonite Palaeo Coordinates: 49°29'04"N 115°00'49"W

Tuesday, 17 August 2021

AMMONITE: INDEX FOSSILS AS TIME KEEPERS

Argonauticeras besairei, José Juárez Ruiz
An exceptional example of the fractal building of an ammonite septum, in this clytoceratid Argonauticeras besairei from the awesome José Juárez Ruiz.

Ammonites were predatory, squidlike creatures that lived inside coil-shaped shells.

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 am sure you know. But the 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.

They were a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. 

These molluscs, commonly referred to as ammonites, are more closely related to living coleoids — octopuses, squid, and cuttlefish) than they are to shelled nautiloids such as the living Nautilus species.

The Ammonoidea can be divided into six orders:

  • Agoniatitida, Lower Devonian - Middle Devonian
  • Clymeniida, Upper Devonian
  • Goniatitida, Middle Devonian - Upper Permian
  • Prolecanitida, Upper Devonian - Upper Triassic
  • Ceratitida, Upper Permian - Upper Triassic
  • Ammonitida, Lower Jurassic - Upper Cretaceous

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. If they are geometric with numerous undivided lobes and saddles and eight lobes around the conch, we refer to their pattern as goniatitic, a characteristic of Paleozoic ammonites.

If they are ceratitic with lobes that have subdivided tips; giving them a saw-toothed appearance and rounded undivided saddles, they are likely Triassic. For some lovely Triassic ammonites, take a look at the specimens that come out of Hallstatt, Austria and from the outcrops in the Humboldt Mountains of Nevada.

Hoplites bennettiana (Sowby, 1826) Christophe Marot
If they have lobes and saddles that are fluted, with rounded subdivisions instead of saw-toothed, they are likely Jurassic or Cretaceous. If you'd like to see a particularly beautiful Lower Jurassic ammonite, take a peek at Apodoceras. Wonderful ridging in that species.

One of my favourite Cretaceous ammonites is the ammonite, Hoplites bennettiana (Sowby, 1826). This beauty is from Albian deposits near Carrière de Courcelles, Villemoyenne, near la région de Troyes (Aube) Champagne in northeastern France.

At the time that this fellow was swimming in our oceans, ankylosaurs were strolling about Mongolia and stomping through the foliage in Utah, Kansas and Texas. Bony fish were swimming over what would become the strata making up Canada, the Czech Republic and Australia. Cartilaginous fish were prowling the western interior seaway of North America and a strange extinct herbivorous mammal, Eobaatar, was snuffling through Mongolia, Spain and England.

In some classifications, these are left as suborders, included in only three orders: Goniatitida, Ceratitida, and Ammonitida. Once you get to know them, ammonites in their various shapes and suturing patterns make it much easier to date an ammonite and the rock formation where it is found.

Ammonites first appeared about 240 million years ago, though they descended from straight-shelled cephalopods called bacrites that date back to the Devonian, about 415 million years ago, and the last species vanished in the Cretaceous–Paleogene extinction event.

They were prolific breeders that evolved rapidly. If you could cast a fishing line into our ancient seas, it is likely that you would hook an ammonite, not a fish. They were prolific back in the day, living (and sometimes dying) in schools in oceans around the globe. We find ammonite fossils (and plenty of them) in sedimentary rock from all over the world.

In some cases, we find rock beds where we can see evidence of a new species that evolved, lived and died out in such a short time span that we can walk through time, following the course of evolution using ammonites as a window into the past.

For this reason, they make excellent index fossils. An index fossil is a species that allows us to link a particular rock formation, layered in time with a particular species or genus found there. 

Generally, deeper is older, so we use the sedimentary layers of rock to match up to specific geologic time periods, rather like the way we use tree rings to date trees. A handy way to compare fossils and date strata across the globe.

References: Inoue, S., Kondo, S. Suture pattern formation in ammonites and the unknown rear mantle structure. Sci Rep 6, 33689 (2016). https://doi.org/10.1038/srep33689

https://www.nature.com/articles/srep33689?fbclid=IwAR1BhBrDqhv8LDjqF60EXdfLR7wPE4zDivwGORTUEgCd2GghD5W7KOfg6Co#citeas

Photos: Argonauticeras besairei from the awesome José Juárez Ruiz.

Photo: Hoplites bennettiana from near Troyes, France. Collection de Christophe Marot

Monday, 16 August 2021

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.

Sunday, 15 August 2021

BUMBLEBEE: HAMDZALAT'SI

This fuzzy yellow and black striped fellow is a bumblebee in the genus Bombus sp., family Apidae. We know him from our gardens where we see them busily lapping up nectar and pollen from flowers with their long hairy tongues.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, bumblebees are known as ha̱mdzalat̕si — though I wonder if this is actually the word for a honey bee, Apis mellifera, as ha̱mdzat̕si is the word for beehive.

I have a special fondness for all bees and look for them both in the garden and in First Nation art.

Bumblebees habit of rolling around in flowers gives us a sense that these industrious insects are also playful. In First Nation art they provide levity — comic relief along with their cousins the mosquitoes and wasps — as First Nation dancers wear masks made to mimic their round faces, big round eyes and pointy stingers. A bit of artistic license is taken with their forms as each mask may have up to six stingers. The dancers weave amongst the watchful audience and swoop down to playfully give many of the guests a good, albeit gentle, poke. 

Honey bees actually do a little dance when they get back to the nest with news of an exciting new place to forage — truly they do. Bumblebees do not do a wee bee dance when they come home pleased with themselves from a successful foraging mission, but they do rush around excitedly, running to and fro to share their excitement. They are social learners, so this behaviour can also signal those heading out to join them as they head back to the particularly good patch of wildflowers. 

Bumblebees are quite passive and usually sting in defence of their nest or if they feel threatened. Female bumblebees can sting several times and live on afterwards — unlike honeybees who hold back on their single sting as its barbs hook in once used and their exit shears it off, marking their demise.

They are important buzz pollinators both for our food crops and our wildflowers. Their wings beat at 130 times or more per second, literally shaking the pollen off the flowers with their vibration. 

And they truly are busy bees, spending their days fully focussed on their work. Bumblebees collect and carry pollen and nectar back to the nest that may be as much as 25% to 75% of their body weight. 

And they are courteous — as they harvest each flower, they mark them with a particular scent to help others of their group know that the nectar is gone. 

The food they bring back to the nest is eaten to keep the hive healthy but is not used to make honey as each new season's queen bees hibernate over the winter and emerge reinvigorated to seek a new hive each Spring. She will choose a new site, primarily underground depending on the bumblebee species, and then set to work building wax cells for each of her fertilised eggs. 

Bumblebees are quite hardy. The plentiful hairs on their bodies are coated in oils that provide them with natural waterproofing. They can also generate more heat than their smaller, slender honey bee cousins, so they remain productive workers in cooler weather.    

We see the first bumblebees arise in the fossil record 100 million years ago and diversify alongside the earliest flowering plants. Their evolution is an entangled dance with the pollen and varied array of flowers that colour our world. 

We have found many wonderful examples within the fossil record, including a rather famous Eocene fossil bee found by a dear friend and naturalist who has left this Earth, Rene Savenye.

His namesake, H. Savenyei, is a lovely fossil halictine bee from Early Eocene deposits near Quilchena, British Columbia — and the first bee body-fossil known from the Okanagan Highlands — and indeed from Canada. 

It is a fitting homage, as bees symbolize honesty, playfulness and willingness to serve the community in our local First Nation lore and around the world — something Rene did his whole life.

Saturday, 14 August 2021

SEA ANEMONES: CNIDARIA

These colourful beauties are sea anemones. They are familiar inhabitants of rocky shores and coral reefs around the world — with some of their brethren found at very low depths in our oceans. They are one of the wonderful examples of the diversity that radiated out of the Cambrian Explosion.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, sea anemones are known as 'mis'ma̱t̕sa. 

These beautiful predatory animals are a common site in tide pools all along the Pacific Coast. They form a large part of many special memories of exploring the tide pools along Storey's Beach on the east side of Vancouver Island as a child. 

Touching their soft tentacles is hypnotic and highly entertaining but our human skin is coated in oils and bacteria that may damage these delicate organisms. 

We sometimes see them turn up in First Nation's art — particularly in association with Kumugwe' or the Copper-Maker, Chief of the undersea world and the one to thank for the rising and ebbing of the tides.

At first glance, they look like beautiful and delicate marine flowers. If you have discovered them in tidepools, you will know that they retract or pull into themselves with the lightest touch. These would-be flowers are predatory marine animals of the order Actiniaria that have graced our oceans for over half a billion years. 

They are named after anemones — Anemonastrum, a genus of flowering plants in the family Ranunculaceae — because of their colourful flower-like appearance. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. 

As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and Hydra. Jellyfish have a complex life cycle that includes both sexual and asexual phases, with the medusa being the sexual stage in most instances. 

A typical sea anemone is a single polyp attached to a hard surface by its base, but some species live in soft sediment and a few float near the surface of the water. The polyp has a columnar trunk topped by an oral disc with a ring of sticky tentacles that fold in towards its central mouth. If they have stung and paralyzed a tasty snack, it is pulled towards the gaping mouth to be consumed. 

The tentacles can be retracted or pulled back inside the body cavity or stretched out and expanded to catch passing prey. They are armed with cnidocytes or stinging cells. In many species, nourishment comes from a symbiotic relationship with single-celled dinoflagellates — zooxanthellae or with green algae, zoochlorellae, that live within the cells. Some species of sea anemone live in association with hermit crabs, small fish or other animals to their mutual benefit.

Most actinarians are sessile — that is, they live attached to rocks or other substrates and do not move, or move only very slowly by contractions of the pedal disk. 

A number of anemones burrow into sand, and a few can even swim short distances, by bending the column back and forth or by "flapping" their tentacles. In all, there are about 1000 species of sea anemone in the world's oceans — including those who live amongst the mythic sea lions that form the posts and beams of Kumugwe''s undersea home.

Sea anemones breed by releasing sperm and eggs through their mouth into the surrounding ocean. The fertilized eggs develop into wee planula larvae that live as tiny planktonic bits floating in the sea. Eventually, they settle on the seafloor and develop directly into juvenile polyps. Sea anemones can also breed asexually. They do this by breaking in half or into smaller pieces that regenerate into polyps.

We sometimes see these beauties kept in saltwater aquariums. I can understand the appeal but it comes with a price. The global trade in marine ornamentals threatens our lovely sea anemone populations. 

Most Actiniaria do not form hard parts that can be recognized as fossils, but a few fossils of sea anemones have been found. The bag-like — almost sea cucumber-like — Mackenzia, from the Middle Cambrian, Stephen Formation in the Canadian Rockies of British Columbia and Alberta, is the oldest fossil identified as a sea anemone. These ancient sea anemones attached themselves to hard surfaces, such as brachiopod shells in a similar fashion to their modern sessile cousins. 

Mackenzia costalis, Walcott 1911
Fourteen specimens of Mackenzia costalis are known from the Greater Phyllopod bed, where they make up less than <0.1% of the fossil community. Mackenzia was originally described by Charles Walcott in 1911 — but as a holothurian echinoderm, which was a reasonable assumption at the time. Once additional specimens had been found and studied, Mackenzia costalis was reclassified as a cnidarian and the great grandparent of our modern sea anemones.

Some fossil sea anemones have also been found from the Lower Cambrian of China. The new find lends support to genetic data that suggests anthozoans — anemones, corals, octocorals and their kin — were one the first Cnidarian groups to diversify. We will likely find more of these rare fossils over time and perhaps get a better view of their long lineage.

Photo: Charles Doolittle Walcott - Charles D. Walcott: Middle Cambrian Holothurians and Medusae. Smithsonian Miscellaneous Collections Volume 57, Number 3 (Publication 2011). City of Washington. Published by the Smithsonian Institution. June 13, 1911. 

References:  

Caron, Jean-Bernard; Jackson, Donald A. (October 2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS. 21 (5): 451–65. doi:10.2110/palo.2003.P05-070R. JSTOR 20173022.

 Durham, J. W. (1974). "Systematic Position of Eldonia ludwigi Walcott". Journal of Paleontology. 48 (4): 750–755. JSTOR 1303225.

Conway Morris, S. (1993). "Ediacaran-like fossils in Cambrian Burgess Shale–type faunas of North America". Palaeontology. 36 (31–0239): 593–635.


Friday, 13 August 2021

THE CALL OF THE WILD: ANTARCTIC FUR SEALS

This little cutie is an Antarctic fur seal pup. He and his Mamma belong to the species Arctocephalus gazella — pinnipeds that live in dense colonies alongside King Penguins. 

These two call the South Georgia islands home, as do 95% of the world's fur seal population.  

Though a wee pup, he can already recognize her voice from all the other lovely Mammas in his busy, noisy colony. Little ones left on the rocky shores while their mother is out hunting will raise their heads and listen for their mother's voice. They can distinguish its vocal pitch over the loud calls of all the other busy Mammas and penguins of the colony. If you look closely, you can see his wee little ears. Antarctic fur seals, unlike some other seal species, have visible ears.  

Seal pups stay with their mother, relying on her lactation milk to help them fatten up and grow healthy and strong. For the first four months of their lives, their mother will feed them on her rich milk, then head out to sea to forage for food. 

Once she is back, she will call out to him and then give him a good sniff upon their reunion, the final confirmation for both parties that the right match has been made. The interaction between mother and pup is tender and heartbreakingly sweet to watch. She only gives birth to one pup (two is rare) each October to December. Pups are born with a sheen of fur and grow their waterproof fur during their first months of life. 

When this little fellow grows up, he will dine on fish, birds (including his penguin pals), squid and krill. Krill are small crustaceans of the order Euphausiacea that look like tiny shrimp. They look similar and are both crustaceans but shrimp hail from the suborder Natantia, order Decapoda and their hearts are located in their heads.

Krill live in all the world's oceans and sadly for them, they make a handy and tasty snack. They form an important part of the oceanic food chain. The krill feed on phytoplankton and zooplankton and then larger animals feed on the krill. 

Krill is Norwegian for small fry of fish. And they are small, indeed — but also tasty, nutritious and easy to catch. Once this little pinniped pup is out hunting on his own, krill will make up the majority of his adult diet. He will need our help to make sure he gets a steady supply. Krill are one of the casualties of ocean acidification from climate change. Hopefully, we will do better so they can, too.

Thursday, 12 August 2021

PLAYFUL WATERBABIES: PORPOISE

Dall's Porpoise
These delightfully friendly and super smart fellows are Dall's porpoise. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, a blowhole is known as a ka̱'was, whether on a dolphin (porpoise) or whale and a porpoise is known as a k̓ulut̕a

In the Pacific Northwest, we see many of their kind — the shy, blunt-nosed harbour porpoise, the social and herd-minded Pacific white-sided dolphin and the showy and social Dall's porpoise.  

Of these, the Dall's porpoise is a particular favourite. These speedy muscular black and white showboats like to ride the bow waves of passing boats — something they clearly enjoy and a thrill for everyone on board the vessel. If you slow down, they will often whisk away, but give them a chance to race you and they may stay with you all afternoon. 

Harbour porpoises are the complete opposite. You are much more likely to see their solid black bodies and wee fin skimming through the waves across the bay as they try to avoid you entirely. Harbour porpoise prefer quiet sheltered shorelines, often exploring solo or in small groups of two or three. 

We sometimes see these lovely marine mammals represented in the art of the First Nations in the Pacific Northwest, particularly along the coast of British Columbia. You will know them from their rather rectangular artistic depiction with a pronounced snout and lacking teeth (though they have them) used to portray killer whales or orca. 

As a group, even considering the shy Harbour porpoise, these marine mammals are social and playful. Humpback whales are fond of them and you will sometimes see them hanging out altogether in the bays and inlets or near the shore. 

They are quite vocal, making lots of distinctive and interesting noises in the water. They squeak, squawk and use body language — leaping from the water while snapping their jaws and slapping their tails on the surface. They love to blow bubbles, will swim right up to you for a kiss and cuddle. 

Each individual has a signature sound, a whistle that is uniquely their own. They use these whistles to tell one of their friends and family members from another.

Porpoise are marine mammals that live in our world's oceans. If it is salty and cold, you can be pretty sure they are there. They breathe air at the surface, similar to humans, using their lungs and inhaling and exhaling through a blowhole at the top of their heads instead of through their snouts. 



Wednesday, 11 August 2021

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.

Tuesday, 10 August 2021

HUMPBACK WHALES: MEGAPTERA NOVAENGLIAE

Look deep into the knowing eye of this magnificent one. He is a Humpback whale, Megaptera novaeangliae, a species of baleen whale for whom I hold a special place in my heart. 

Baleens are toothless whales who feed on plankton and other wee oceanic tasties that they consume through their baleens, a specialised filter of flexible keratin plates that frame their mouth and fit within their robust jaws.

Baleen whales, the mysticetes, split from toothed whales, the Odontoceti, around 34 million years ago. The split allowed our toothless friends to enjoy a new feeding niche and make their way in a sea with limited food resources. There are fifteen species of baleen whales who inhabit all major oceans. Their number include our humbacks, grays, right whales and the massive blue whale. Their territory runs as a wide band running from the Antarctic ice edge to 81°N latitude. These filter feeders

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, whales are known as g̱wa̱'ya̱m. Both the California grey and the Humpback whale live on the coast. Only a small number of individuals in First Nation society had the right to harpoon a whale. It was generally only the Chief who was bestowed this great honour. Humpback whales like to feed close to shore and enter the local inlets. Around Vancouver Island and along the coast of British Columbia, this made them a welcome food source as the long days of winter passed into Spring.

Humpback whales are rorquals, members of the Balaenopteridae family that includes the blue, fin, Bryde's, sei and minke whales. The rorquals are believed to have diverged from the other families of the suborder Mysticeti during the middle Miocene. 

While cetaceans were historically thought to have descended from mesonychids— which would place them outside the order Artiodactyla— molecular evidence supports them as a clade of even-toed ungulates — our dear Artiodactyla. 

It is one of the larger rorqual species, with adults ranging in length from 12–16 m (39–52 ft) and weighing around 25–30 metric tons (28–33 short tons). The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. It is known for breaching and other distinctive surface behaviours, making it popular with whale watchers.

Both male and female humpback whales vocalize, but only males produce the long, loud, complex "song" for which the species is famous. Males produce a complex soulful song lasting 10 to 20 minutes, which they repeat for hours at a time. I imagine Gregorian Monks vocalizing their chant with each individual melody strengthening and complimenting that of their peers. All the males in a group produce the same song, which differed in each season. Its purpose is not clear, though it may help induce estrus in females and bonding amongst the males.

Humpback Whale, Megaptera novaeangliae
Found in oceans and seas around the world, humpback whales typically migrate up to 25,000 km (16,000 mi) each year. 

They feed in polar waters and migrate to tropical or subtropical waters to breed and give birth, fasting and living off their fat reserves. Their diet consists mostly of krill and small fish. 

Humpbacks have a diverse repertoire of feeding methods, including the bubble net technique.

Humpbacks are a friendly species that interact with other cetaceans such as bottlenose dolphins. They are also friendly and oddly protective of humans. You may recall hearing about an incident off the Cook Islands a few years back. In September of 2017, Nan Hauser was snorkeling and ran into a tiger shark. Two adult humpback whales rushed to her aid, blocking the shark from reaching her and pushing her back towards the shore. We could learn a thing or two from their kindness. We have not been as good to them as they have been to us.

Like other large whales, the humpback was a tasty and profitable target for the whaling industry. My grandfather and uncle participated in that industry out of Coal Harbour on northern Vancouver Island back in the 1950s. 

Six whaling stations operated on the coast of British Columbia between 1905 and 1976. Two of these stations were located at Haida Gwaii, one at Rose Harbour and the other at Naden Harbour. Over 9,400 large whales were taken from the waters around Haida Gwaii. The catch included blue whales, fin whales, sei whales, humpback whales, sperm whales and right whales. In the early years of the century, primarily humpback whales were taken. In later years, fin whales and sperm whales dominated the catch. 

Whales were hunted off South Moresby in Haida Gwaii, on the north side of Holberg Inlet in the Quatsino Sound region. It was the norm at the time and a way to make a living, especially for those who had hoped to work in the local coal mine but lost their employment when it shut down. 

While my First Nations relatives hunted whales in small numbers, my Norwegian relatives participated in the hunt on such a scale that it nearly led to the extinction of our lovely Humpbacks before the process was banned back in the 1960s. The Coal Harbour Whaling Station closed in 1967. Once it had closed, my grandfather Einar Eikanger took to fishing and my uncle Harry lost his life when he slipped and fell over the side of the boat. He was crushed between the hull and a Humpback in rough seas. The Gods will have their sacrifice.

Humpback populations have partially recovered to build their population up to 80,000 animals worldwide since the 1960s but entanglement in fishing gear, collisions with ships, and noise pollution continue to negatively impact the species. So be kind if you see them. Turn your engine off and see if you can hear their soulful cries echoing in the water.

I did up a video on Humpback Whales over on YouTube so you could see them in all their majesty. Here is the link: https://youtu.be/_Vbta7kQNoM

Sunday, 8 August 2021

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.

Friday, 6 August 2021

ROCK LOBSTER: HOMARUS

An artfully enhanced example of Homarus hakelensis, an extinct genus of fossil lobster belonging to the family Nephrophidae. Homarus is a genus of lobsters, which include the common and commercially significant species Homarus americanus (the American lobster) and Homarus gammarus (the European lobster).

The Cape lobster, which was formerly in this genus as H. capensis, was moved in 1995 to the new genus Homarinus.

Lobsters have long bodies with muscular tails and live in crevices or burrows on the seafloor. Three of their five pairs of legs have claws, including the first pair, which are usually much larger than the others.

Highly prized as seafood, lobsters are economically important and are often one of the most profitable commodities in coastal areas they populate. Commercially important species include two species of Homarus — which looks more like the stereotypical lobster — from the northern Atlantic Ocean, and scampi — which looks more like a shrimp — the Northern Hemisphere genus Nephrops and the Southern Hemisphere genus Metanephrops. Although several other groups of crustaceans have the word "lobster" in their names, the unqualified term lobster generally refers to the clawed lobsters of the family Nephropidae.

Clawed lobsters are not closely related to spiny lobsters or slipper lobsters, which have no claws or chelae, or to squat lobsters. The closest living relatives of clawed lobsters are the reef lobsters and the three families of freshwater crayfish. 

This cutie was found in Cretaceous outcrops at Hâdjoula. The sub‐lithographical limestones of Hâqel and Hâdjoula, in northwest Lebanon, produce beautifully preserved shrimp, fish, and octopus. The localities are about 15 km apart, 45 km away from Beirut and 15 km away from the coastal city of Jbail.