Massive trove of Canadian fossils gives near-unprecedented glimpse of Cambrian explosion

A site in the Kootenay National Park has proved a fantastic source of fossils from the Cambrian explosion, 542 million years ago.

In 2012, geologists discovered a major haul of fossils in Canada’s Kootenay National Park, in the Rocky Mountains near Calgary, Alberta. The find looked like it could shed further light on one of the most critical periods in the history of life on Earth, the Cambrian explosion, 542 million years ago - and the first study of its specimens, published in the journal Nature Communications, reveals that the find will “increase our understanding of early animal evolution” in an almost unparalleled way.

While there is evidence that life existed on Earth at least 3.5 billion years ago, life as we know it - multi-cellular and adapted to almost every part of the planet - appeared in what is called the Cambrian explosion, 542 million years ago. This was the era before animals colonised land, and indeed this period coincided with the first era of algae-like plants adapting to survive above water on the edges of bodies of water.

Over the course of around 80 million years the rate of evolution accelerated vastly, and the ancestors of almost all of the major phyla we see today first emerged. Quite why this happened is the subject of debate among scientists - it could have been any number of environmental or genetic factors - but there seemed to have been a relative frenzy of evolutionary competition.

The previously-dominant Ediacarans, which looked a bit like large floating sacks, were usurped and made extinct by the emergence of creatures that developed physical characteristics we still see today, like internal layering that separates digestive tracts from other organs, or having distinct “fronts” and “backs” (a trait known as bilateral symmetry). For an idea of what creatures exist today that missed out on all this, look to jellyfish.

In the rush to try and fill each new ecological niche, there were thousands of experiments that resemble nothing like anything that lives today. There was the spiky grazer Orthrozanclus and the superhero shrimp Stanleycaris; the bristleworm Insolicorypha and the arthopod Marrella, with huge spines on its head. There were also trilobites, thousands and thousands of different trilobites.

But these creatures lived in the sea, and were usually no more than a few centimetres in length at most. When they died - as they no doubt did by the million - they will have been eaten by other scavenging animals within a short time of settling on the sea floor. Our fossil record is dependent entirely on what were ancient landslides, when massive amounts of rock fell into the sea to crush entire shorelines, fossilising them. The few sites where this has happened, with whole ecosystems frozen in stone, are amazing - and none is better than the Burgess Shale. Nowhere else are the soft bodies of the ancient Cambrian explosion better-preserved, with detail so fine it’s possible to make out individual antennae or legs.

The original Burgess Shale find was in 1909, in the Yoho National Park, by palaeontologist Charles Walcott. It was formed by what’s known as a Lagerstätte formation, a particular kind of sedimentary preservation that happens so quickly not even microbes have time to break the tissue down, which is key to preserving as much detail as possible. Walcott spent decades gathering more than 65,000 fossils from the site, with its major significance only realised in the 1960s. And, while the Shale itself extends beyond the Yoho National Park, the best fossils were always found at Walcott’s original site.

However, it appears that the site in Kootenay National Park now rivals it for importance. The team of researchers - from institutes including the Royal Ontario Museum, the University of Toronto, and Uppsala University - gathered as many as 3,000 fossil specimens representing 50 different species in only 15 days.

The study’s lead author, Jean-Bernard Caron from the Royal Ontario Museum, said: "This new discovery is an epic sequel to a research story that began at the turn of the previous century, and there is no doubt in my mind that this new material will significantly increase our understanding of early animal evolution. The rate at which we are finding animals – many of which are new – is astonishing, and there is a high possibility that we'll eventually find more species here than at the original Yoho National Park site, and potentially more than from anywhere else in the world.”

Some of the preservation is so good that internal organs are visible. There’s also further evidence to support that hypothesis that Pikaia gracilens - a 4cm-long creature that looks a bit like an eel with tentacles - is the earliest known creature with the characteristics of vertebrates. It could even be the common ancestor of all vertebrates alive today.

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

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The best Instagram accounts to follow if you love space

As new space findings hit the news on an almost daily basis, the app offers an alternative window onto the universe.

If there’s anything that can break us away from the humdrum monotony of modern life, it’s space. It renders us awe-struck and captures our imagination with its vastness and surreal imagery, and as astronomy-related research expands, cosmic mysteries continue to unfold.

Whether it’s the occurrence of rare celestial events, the discovery of exoplanets that could potentially harbour life, or the confirmation of gravitational waves that ripple through the space-time continuum, it seems that there are new findings propelled onto our newsfeeds daily.  

Yet one of the best ways of keeping up to date with the latest research and projects at the frontier of space is on Instagram, the social media platform. Here are some of the accounts you should be following to get the greatest insight into space:

1. SpaceX (@spacex)

The aerospace company SpaceX designs spacecrafts and reusable rockets in the hope that their technology can one day make human life multi-planetary. Spearheaded be CEO Elon Musk, the company has the lofty ambition of one day colonising Mars. Below is a spectacular image of the company’s Falcon 9 rocket in its first-stage entry:

 

Photographer unexpectedly captures Falcon 9 second stage burn and first stage entry @slowcountrylife

A photo posted by SpaceX (@spacex) on

 

2. International Space Station (@iss)

The International Space Station, a habitable satellite whirling around the Earth approximately 16 times per day in low orbit, has an Instagram feed displaying the equipment on board as well as stunning pictures of the Earth from a distance. Here’s a picture from the station 250 miles above earth depicting the Earth as an azure blue marble:

 

The blue of the #bahamas can't be mistaken, even from 250 miles above. #YearInSpace #nasa #space #spacestation : @stationcdrkelly

A photo posted by International Space Station (@iss) on

 

3. Tim Peake (@astro_timpeake)

Currently aboard the International Space Station is Tim Peake, a British astronaut. As he has carried out his work on Expedition 46/47 on the station, he has shared a range of photos of Earth that he has shot with his Nikon D4 from the vantage point of space, from reefs off the coast of Mozambique to the glint of sun highlighting Vancouver Island. Here we have a clear image of the Pacific “Ring of Fire”:

 

3/3: The Pacific ‘Ring of Fire’ clear to see amongst the volcanoes of Kamchatka, Russia

A photo posted by Tim Peake (@astro_timpeake) on

 

4. Scott Kelly (@stationcdrkelly)

Scott Kelly is an engineer and a retired American astronaut who recently spent a year commanding the International Space Station, travelling 143,846,525 miles around our globe in the process. A quick scroll through his profile will demonstrate just how profound his experience must have been at the shores of space, and includes a host of images of the aurora borealis:

 

#GoodMorning #aurora and the Pacific Northwest! #YearInSpace #northernlights #beautiful #morning #space #spacestation #iss

A photo posted by Scott Kelly (@stationcdrkelly) on

 

5. Nasa Goddard (@nasagoddard)

Nasa’s Goddard Space Flight Centre was the company’s very first flight centre. It’s the largest of its kind, and the official Instagram account for the centre serves as a highlight reel for everything NASA is working on. There are behind-the-scenes looks at the James Webb Space Telescope under construction, computer-simulated images of supermassive black holes, and clear views of distant galaxies captured by the Hubble Space Telescope:

 

Observations by the NASA/ESA Hubble Space Telescope have taken advantage of gravitational lensing to reveal the largest sample of the faintest and earliest known galaxies in the universe. Some of these galaxies formed just 600 million years after the big bang and are fainter than any other galaxy yet uncovered by Hubble. The team has determined for the first time with some confidence that these small galaxies were vital to creating the universe that we see today. An international team of astronomers, led by Hakim Atek of the Ecole Polytechnique Fédérale de Lausanne, Switzerland, has discovered over 250 tiny galaxies that existed only 600-900 million years after the big bang— one of the largest samples of dwarf galaxies yet to be discovered at these epochs. The light from these galaxies took over 12 billion years to reach the telescope, allowing the astronomers to look back in time when the universe was still very young. Although impressive, the number of galaxies found at this early epoch is not the team’s only remarkable breakthrough, as Johan Richard from the Observatoire de Lyon, France, points out. “The faintest galaxies detected in these Hubble observations are fainter than any other yet uncovered in the deepest Hubble observations.” By looking at the light coming from the galaxies the team discovered that the accumulated light emitted by these galaxies could have played a major role in one of the most mysterious periods of the universe’s early history — the epoch of reionization. Reionization started when the thick fog of hydrogen gas that cloaked the early universe began to clear. Ultraviolet light was now able to travel over larger distances without being blocked and thus the universe became transparent to ultraviolet light. Credit: NASA/ESA #nasagoddard #Hubble #HST #space #galaxy

A photo posted by NASA Goddard (@nasagoddard) on

 

6. Roscosmos (@roscosmosofficial)

Roscosmos is the Russian Federal Space Agency at the heart of all space endeavours in Russia. The agency is involved in the maintenance and progression of the International Space Station, and is working on its own research projects such as a planned robotic mission to one of Mars’s moons.  Here’s the launch of a rocket from the Vostochny Cosmodrome which is under construction:

 

7. Nasa (@nasa)

Over the years, Nasa has firmly committed to pushing the boundaries of space exploration, and, as its 12.3m Instagram acolytes would agree, it has been successful. As part of the Frontier Fields campaign investigating galaxy clusters, a recent deep field image from the Hubble revealed bounds of galaxies in the constellation of Leo:

 

Nearly as deep as the Hubble Ultra Deep Field, which contains approximately 10,000 galaxies, this incredible image from the Hubble Space Telescope reveals thousands of colorful galaxies in the constellation of Leo (The Lion). This vibrant view of the early universe was captured as part of the Frontier Fields campaign, which aims to investigate galaxy clusters in more detail than ever before, and to explore some of the most distant galaxies in the universe. Galaxy clusters are massive. They can have a tremendous impact on their surroundings, with their immense gravity warping and amplifying the light from more distant objects. This phenomenon, known as gravitational lensing, can help astronomers to see galaxies that would otherwise be too faint, aiding our hunt for residents of the primordial universe. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt #nasa #hubble #astronomy #science #space #galaxy #galaxies

A photo posted by NASA (@nasa) on