Sunday 10 June 2018

Wednesday 6 June 2018

AMMONITE: PART AND COUNTERPART

Ammonites 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 rock to match up to specific geologic time periods, rather the way we use tree-rings to date trees.

Sunday 3 June 2018

CaCO3 + CO2 + H2O → Ca (HCO3)2

 
Those of you who live near the sea understand the compulsion to collect shells. They add a little something to our homes and gardens.

With a strong love of natural objects, my own home boasts several stunning abalone shells conscripted into service as both spice dish and soap dish.

As well as beautiful debris, shells also played an embalming role as they collect in shell middens from coastal communities. Having food “packaging” accumulate in vast heaps around towns and villages is hardly a modern phenomenon.

Many First Nations sites were inhabited continually for centuries. The discarded shells and scraps of bone from their food formed enormous mounds, called middens. Left over time, these unwanted dinner scraps transform through a quiet process of preservation.

Time and pressure leach the calcium carbonate, CaCO3, from the surrounding marine shells and help “embalm” bone and antler artifacts that would otherwise decay. Useful this, as antler makes for a fine sewing tool when worked into a needle. Much of what we know around the modification of natural objects into tools comes from this preservation.

Calcium carbonate is a chemical compound that shares the typical properties of other carbonates. CaCO3 is common in rocks and shells and is a useful antacid for those of you with touchy stomachs. In prepping fossil specimens embedded in limestone, it is useful to know that it reacts with stronger acids, releasing carbon dioxide: CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

For those of you wildly interested in the properties of CaCO3, may also find it interesting to note that calcium carbonate also releases carbon dioxide on when heated to greater than 840°C, to form calcium oxide or quicklime, reaction enthalpy 178 kJ / mole: CaCO3 → CaO + CO2.

Calcium carbonate reacts with water saturated with carbon dioxide to form the soluble calcium bicarbonate. Bone already contains calcium carbonate, as well as calcium phosphate, Ca2, but it is also made of protein, cells and living tissue.

Decaying bone acts as a sort of natural sponge that wicks in the calcium carbonate displaced from the shells. As protein decays inside the bone, it is replaced by the incoming calcium carbonate, making makes the bone harder and more durable.

The shells, beautiful in their own right, make the surrounding soil more alkaline, helping to preserve the bone and turning the dinner scraps into exquisite scientific specimens for future generations.

Monday 21 May 2018

ORCA: MAX'INUX

Orca, Black Fish or Killer Whale — these toothed whales in the oceanic dolphin family are one of the most recognized species in the world.

These large marine mammals are easily distinguished by their black-and-white colouration, large dorsal fin and a sleek, streamlined body. You can often get a peek at their top fin and just enough of their distinctive white eye patch to id

Their genus name Orcinus means "of the kingdom of the dead."

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, orca or killer whales are known as max̱'inux̱.

Saturday 12 May 2018

ELEPHANT

When an elephant drinks, it sucks as much as 2 gallons (7.5 liters) of water into its trunk at a time. Then it curls its trunk under, sticks the tip of its trunk into its mouth, and blows. Out comes the water, right down the elephant's throat.

Since African elephants live where the sun is usually blazing hot, they use their trunks to help them keep cool. 

First they squirt a trunkful of cool water over their bodies. Then they often follow that with a sprinkling of dust to create a protective layer of dirt on their skin. Elephants pick up and spray dust the same way they do water—with their trunks.

Elephants also use their trunks as snorkels when they wade in deep water. An elephant's trunk is controlled by many muscles. Two fingerlike parts on the tip of the trunk allow the elephant to perform delicate manoeuvres such as picking a berry from the ground or plucking a single leaf off a tree. 

Elephants can also use their trunk to grasp an entire tree branch and pull it down to its mouth and to yank up clumps of grasses and shove the greenery into their mouths.

When an elephant gets a whiff of something interesting, it sniffs the air with its trunk raised up like a submarine periscope. If threatened, an elephant will also use its trunk to make loud trumpeting noises as a warning.

Elephants are social creatures. They sometimes hug by wrapping their trunks together in displays of greeting and affection. Elephants also use their trunks to help lift or nudge an elephant calf over an obstacle, to rescue a fellow elephant stuck in mud, or to gently raise a newborn elephant to its feet. And just as a human baby sucks its thumb, an elephant calf often sucks its trunk for comfort. One elephant can eat 300 pounds (136 kilograms) of food in one day.

People hunt elephants mainly for their ivory tusks. Adult females and young travel in herds, while adult males generally travel alone or in groups of their own.

HUA MOUNTAINS


Friday 11 May 2018

QUENSTEDTOCERAS WITH PATHOLOGY

What you are seeing here is a protuberance extruding from the venter of Quenstedtoceras cf. leachi (Sowerby). It is a pathology in the shell from hosting immature bivalves that shared the seas with these Middle Jurassic, Upper Callovian, Lamberti zone fauna from the Volga River basin. The collecting site is the now inactive Dubki commercial clay quarry and brickyard near Saratov, Russia. 

The site has produced thousands of ammonite specimens. A good 1,100 of those ended up at the Black Hills Institute of Geological Research in Hill City, South Dakota. 

Roughly 1,000 of those are Quenstedtoceras (Lamberticeras) lamberti and the other 100 are a mix of other species found in the same zone. These included Eboraciceras, Peltoceras, Kosmoceras, Grossouvria, Proriceras, Cadoceras and Rursiceras

What is especially interesting is the volume of specimens — 167 Quenstedtoceras (Lamberticeras) lamberti and 89 other species in the Black Hills collection — with healed predation injuries. It seems Quenstedtoceras (Lamberticeras) lamberti are the most common specimens found here and so not surprisingly the most common species found injured. Of the 1,000, 655 of the Quenstedtoceras (Lamberticeras) lamberti displayed some sort of deformation or growth on the shell or had grown in a tilted manner. 

Again, some of the Q. lamberti had small depressions in the centre likely due to a healed bite and hosting infestations of the immature bivalve Placunopsis and some Ostrea

The bivalves thrived on their accommodating hosts and the ammonites carried on, growing their shells right up and over their bivalve guests. This relationship led to some weird and deformities of their shells. They grow in, around, up and over nearly every surface of the shell and seem to have lived out their lives there. It must have gotten a bit unworkable for the ammonites, their shells becoming warped and unevenly weighted. Over time, both the flourishing bivalves and the ammonite shells growing up and over them produced some of the most interesting pathology specimens I have ever seen.    

In the photo here from Emil Black, you can see some of the distorted shapes of Quenstedtoceras sp. Look closely and you see a trochospiral or flattened appearance on one side while they are rounded on the other. 

All of these beauties hail from the Dubki Quarry near Saratov, Russia. The ammonites were collected in marl or clay used in brick making. The clay particles suggest a calm, deep marine environment. One of the lovely features of the preservation here is the amount of pyrite filling and replacement. It looks like these ammonites were buried in an oxygen-deficient environment. 

The ammonites were likely living higher in the water column, well above the oxygen-poor bottom. An isotopic study would be interesting to prove this hypothesis. There's certainly enough of these ammonites that have been recovered to make that possible. It's estimated that over a thousand specimens have been recovered from the site but that number is likely much higher. But these are not complete specimens. We mostly find the phragmocones and partial body chambers. Given the numbers, this may be a site documenting a mass spawning death over several years or generations.

If you fancy a read on all things cephie, consider picking up a copy of Cephalopods Present and Past: New Insights and Fresh Perspectives edited by Neil Landman and Richard Davis. Figure 16.2 is from page 348 of that publication and shows the hosting predation quite well. 

Photos: Courtesy of the deeply awesome Emil Black. These are in his personal collection that I hope to see in person one day. 

It was his sharing of the top photo and the strange anomaly that had me explore more about the fossils from Dubki and the weird and wonderful hosting relationship between ammonites and bivalves. Thank you, my friend!

MORRAINE LAKE


Wednesday 9 May 2018

Thursday 3 May 2018

AGASSIZ

A wonderful replica of Furo Philpotae (Agassiz) fossil fish from the Jurassic of Lyme Regis, UK by Natural Selection Fossils.

The original specimen that this replica is made from is the most complete ever found and considered the best preserved in the world. This beauty with a ton of exquisite detail measures approximately 87 cm in length.

Monday 30 April 2018

Saturday 21 April 2018

GINKO BILOBA

Each year, I grow Ginko and Metasequoia to plant on Earth Day. They serve as an homage to the environment and a offering to Gaia for a cleaner, kinder world.

RAIN SHOWERS BRING...


Tuesday 17 April 2018

Thursday 12 April 2018

BONE TO STONE

Calcium carbonate reacts with water saturated with carbon dioxide to form the soluble calcium bicarbonate. Bone already contains calcium carbonate, as well as calcium phosphate, Ca2, but it is also made of protein, cells and living tissue.

Decaying bone acts as a sort of natural sponge that wicks in the calcium carbonate displaced from the shells. As protein decays inside the bone, it is replaced by the incoming calcium carbonate, making the bone harder and more durable.

Wednesday 11 April 2018

Tuesday 10 April 2018

Monday 9 April 2018

Thursday 5 April 2018

AMMONITE BEAUTY

Varying in size from millimeters to meters across, ammonites are prized as both works of art and index fossils helping us date rock. The ammonites were cousins in the Class Cephalopoda, meaning "head-footed," closely related to modern squid, cuttlefish and octopus. Cephalopods have a complex eye structure and swim rapidly. The ones shown here are from a Sinemurian site I visited a few years back high up in the Canadian Rockies.

Ammonites used these evolutionary benefits to their advantage, making them successful marine predators. I shared some ammonites with my wee paleontologist cousins this weekend, Madison and Melaina. They were impressed with the amazing range of species and body styles. Their favorites were the ones from Alberta and England with their original mother of pearl still intact.

Tuesday 3 April 2018

Sunday 18 March 2018

Friday 16 March 2018

LATE OLIGOCENE SOOKE FORMATION

Desmostylus, Royal Ontario Museum Collection
The late Oligocene Sooke Formation outcrops at several coastal localities along the South-west coast of Vancouver Island. The most well-known and most collected of these are the exposures to the west of Muir Creek.

The formation contains marine fossils including a diversity of intertidal and near shore gastropods, bivalves, abundant barnacle (Balanus) plates, and rare coral, echinoid (sand dollar) and mammal (Desmostylus) fossils.

When these fossils were laid down, the Northeastern Pacific had cooled to near modern levels and the taxa that were preserved as fossils bear a strong resemblance to those found living today beneath the Strait of Juan de Fuca. In fact, many of the Sooke Formation genera are still extant.

We find near shore and intertidal genera such as Mytilus (mussels) and barnacles, as well as more typically subtidal predatory globular moon snails, surf clams (Spisula, Macoma), and thin, flattened Tellin clams.

In several places, there are layers thickly strewn with fossils, suggesting that they were being deposited along a strand line. The rock is relatively coarse-grained sandstone, suggesting a high energy environment as would be found near a beach.

The outcrops at Muir Creek make for a great day trip. This is a family friendly site best enjoyed and collected at low tide.

Monday 12 March 2018

Saturday 10 March 2018

Sunday 4 March 2018