Sunday 30 April 2017

THE BIRTHPLACE OF LIFE

For millennia, we've sat at the edge of the world, taking in the impossible magnitude of the ocean.

Her beauty, her storms, such abundance and diversity of life amidst both the tranquillity and unforgiving power that this immensely deep and mostly unexplored frontier hold for us.

Our distant relatives and even those who meditate on these vast pools of blue and green today see the ocean as the birthplace of life. It's the story we tell our children, and they, in turn, tell their children's children. It's a reasonable conclusion. Upwelling currents bring cold, nutrient-rich water from the bottom to the surface. In this primordial soup, vitally important organic and inorganic compounds mix ceaselessly and give us the perfect conditions for photosynthesis, and by all accounts, the basic building blocks of life.

But, rather than the birthplace, I postulate that the ocean is simply the mixing ground for the expansion of life that began elsewhere. It is also possible, as yet we do not know, that these two streams ran in tandem. The delight of science is that we may one day know for sure.

From the oceans, it's just a slow crawl, evolutionarily speaking, from the sea to the terrestrial life we see today. So where to look for the beginnings. That story is a much harsher one. We find microbes of the Domain Archaea, prokaryotic single-celled microorganisms, distinct from bacteria and eukaryotes, living in some of the world's most unlikely and inhospitable places.

Extremely adaptable, Archaea not only survive but thrive in harsh environments, hot, cold, brutally acidic, you name it. But beyond the hot pools and salt lakes, they have also been found in rather pedestrian habitats, in soils, marshlands, and our oceans.

You may be surprised to learn that at this very moment, they are living in your colon, oral cavity, and skin. The methanogens that inhabit our guts have a symbiotic role, helping us with digestion.

Archaea possess genes and several metabolic pathways that allow for transcription and translation. They are able to access more energy sources than their wee microorganism peers, making use of sugars, ammonia, metal ions and hydrogen gas.

The salt-tolerant, Haloarchaea, uses sunlight as an energy source. All reproduce asexually by binary fission, fragmentation or budding and have been doing so for a very long time. Much to our surprise, Archaea have been found making their home in granite more than 3 kilometres beneath the Earth's surface. Well-preserved Archaea microfossils can be found between the quartz sand grains of the oldest known beach on Earth at Strelley Pool, about 1,500 km north of Perth, Australia. They were thriving here over 3.4 billion years ago in an oxygen-free world, metabolizing sulphur-based compounds and giving rise to the life we see today.

But there are also tubelike fossils, stromatolites, possible ancient microbial mats found in 3.77 billion-year-old rocks. Are these the birth of life? The court's still out. Plate tectonics is the Earth's greatest recycling program with only a handful of outcrops older than 3 billion years. Combine that with baking, cooling, subduction and pressure and it makes solving this ancient mystery even more challenging. So, the birthplace of life? So far, the best contender are the wee beasties from the planet's oldest beach.



Saturday 29 April 2017

Friday 28 April 2017

Tuesday 25 April 2017

ENHYDRA LUTRIS INSIDENTE GALEAE

Sea Otter / Enhydra lutris / Vancouver Island
Sea otters are playful, marine mammals with webbed hind feet and water-repelling fur perfectly adapted to the chilly seas in which they live. 

Sunday 23 April 2017

EOCENE PLANT & MAMMAL SITE

Reinforcing the block to safely transport the fossil trackway

Wednesday 19 April 2017

Monday 10 April 2017

TECTONIC SHIFTING: BAJA BC

Some 270 million plus years ago, had one wanted to buy waterfront property in what is now British Columbia, you’d be looking somewhere near Kakwa Provincial Park between Prince George and the Alberta border. 

The rest of the province had yet to arrive but would be made up of over twenty major terranes from around the Pacific. 

The rocks that would eventually become the Cariboo Mountains were far out in the Pacific Ocean, down near the equator.

With tectonic shifting, these rocks drifted north-eastward, riding their continental plate, until they collided with and joined the Cordillera in what is now British Columbia. Continued pressure and volcanic activity helped create the tremendous slopes of the Cariboo Range we see today with repeated bouts of glaciation during the Pleistocene carving their final shape.

Friday 7 April 2017

FARALLON PLATE

The Farallon Plate took a turn north some 57 million years ago, sweeping much of western coastal Oregon along with it. 

By the middle Oligocene, the Cascadia Subduction Zone was in full force with growing pressure erupting volcanoes along the Western Cascades, a pattern that was to continue well into the Miocene. 

The soft ocean sediments of Oregon contain beautifully preserved gastropods, bivalves and cephalopods.