The Cabrières Biota: an Ordovician Snapshot

Christian McCall's/Prehistorica Art's illustration of the Cabrières Biota, detail. (2024?)When I saw “epic importance” and “fossils” in the same headline, I figured whatever’d been found would be at least somewhat out of the ordinary. I’ve learned to take journalistic puffery with at least a few grains of salt.

But this time, the fossils really were something important: exceptionally well-preserved samples from a 470,000,000 year old biome.


“Epic Importance”, Fabulous Fossils, and a Calamitous Crisis

Christian McCall's/Prehistorica Art's illustration of the Cabrières Biota. (2024?) via ResearchGate, used w/o permission. A row of Ampyx (trilobites). Behind the trilobites, a lobopodian, a chelicerate, cnidarians (blue), sponges (green), thin branching algae (red and green) and hemichordate tubes (purple), along with some molluscs. Bivalved arthropods inhabit the water column along with graptolites.'
Christian McCall’s illustration: the Cabrières Biota.

Fossils from the Cabrières Biota probably do have “worldwide importance”, at least to folks who study long-gone ecosystems.

What got my attention, though, after the headlines, was the “place of refuge for animals escaping global warming” angle in these — or this — story. The good news is that I finally backed out of that rabbit hole.

Amateur Paleontologists Discover Site of Epic Importance—400 Fossils from 470M Years Ago Amid Global Warming
Good News Network (February 10, 2024)

“Two amateur paleontologists have discovered a site of ‘worldwide importance’ in France containing nearly 400 fossils that date back 470 million years.

“The exceptionally well-preserved fossils provide evidence that this site was a place of refuge for animals escaping global warming….”

Amateur paleontologists find 400 fossils dating back millions of years ago
Isobel Williams via SWNS, Talker News; NBC Right Now (February 9, 2024)

“Two amateur paleontologists have discovered a site of ‘worldwide importance’ in France containing nearly 400 fossils that date back 470 million years.

“The exceptionally well-preserved fossils provide evidence that this site was a place of refuge for animals escaping global warming….”

Before I get into why finding a bunch of Ordovician fossils is a big deal — and, for that matter, what “Ordovician” is — a little reassurance and explanation.

Scott Adam's 'Dilbert' strip: Dogbert's Good News Show. ('We'll all die!')I’m not going to rant — well, maybe just a little — about “global warming”.

Basically, I don’t think we’re all gonna die. But I won’t try convincing you that conditions in California and New York City are just simply fabulous.

I am, however, going to talk a little about news outlets.

Down a Rabbit Hole —

John Tenniel's 'The White Rabbit' from 'Lewis Carroll's 'The Nursery Alice.' (1890) from the British Library, via WikipediaArticles about the recent fossil find weren’t identical on NBC Right Now and Good News Network.

Each had its own headline, and (somewhat) different text after the first two paragraphs.

After noticing that the Good News Network’s author was listed as “Good News Network”, I got curious about who actually wrote the article.

Particularly since the NBC Right Now’s author was “Isobel Williams” and “Talker News”, and the NBC Right Now’s dateline was a day earlier that Good News Network’s.

Eventually, I found another “fossil” article by Isobel Williams: datelined last month.

Some of world’s oldest fossils found are 565 million years old
By Talker News, Isobel Williams via SWNS (January 15, 2024, updated January 15, 2024)

“Some of the world’s oldest fossils found in Wales have been precisely dated for the first time at 565 million years old.

“Scientists say the remains of the first complex multicellular life capture a key moment in the evolution of life on Earth.

“The fossils are helping to track the pivotal moment in history when the seas began teeming with new lifeforms — after four billion years of containing only single-celled organisms.

“The fossils were found by researchers in the countryside of South West Wales in the Coed Cochion Quarry….”

Then I noticed that the January fossil article was about fossils found in South West Wales, not France. So I backed out of the ‘where did this/these article(s) come from’ rabbit hole.

By that time, it was Wednesday afternoon.

I’m guessing that “the Coed Cochion Quarry” isn’t coeducational, but I am not going to get distracted by Welsh language, landforms, and nomenclature.

— And Out again

Nicholas Konrad's illustration for The New Yorker's 'Is the Media Prepared for an Extinction-Level Event?', using photographs from Alamy / Getty
Nicholas Konrad’s illustration for “Is the Media Prepared…”, The New Yorker. (detail) (February 10, 2024)

After this dire digression, I’ll get back to fossils and science. Really.

Is the Media Prepared for an Extinction-Level Event?
Clare Malone, The New Yorker (February 10, 2024)

“Ads are scarce, search and social traffic is dying, and readers are burned out. The future will require fundamentally rethinking the press’s relationship to its audience.

“My first job in media was as an assistant at The American Prospect, a small political magazine in Washington, D.C., that offered a promising foothold in journalism….”

Clare Malone’s piece in The New Yorker discussed quite a few factors involved in what the author calls mass media and the current calamitous crisis. Did a pretty good job, too.

Brian H. Gill's 'Totally Depressing News Network: TDNN'.But, even now, I suspect that at least some folks might take The News more seriously, if reporters and editors would consider the possibility that:

  • “Chaotic”, “complicated”, and “fast” are not synonyms
  • Everything is not an “unprecedented” crisis

Oh, boy. After emerging from this week’s rabbit hole, here’s what I learned about my sources for the “400 fossils” article(s) —

NBC Right Now is a “Tri-Cities/Yakima News | Nonstop Local News” station in Kennewick, Washington.

SWNS is a content provider of some sort. I hadn’t run across it before this week.

Good News Network is an outfit that shows up in my news feed occasionally.

Here’s what Good News Now and SWNS say about themselves.

About GNN
OUR MISSION, OUR PASSION
“…good news itself is not in short supply; the broadcasting of it is….
“…Thomas Jefferson said the job of journalists was to portray accurately what was happening in society. GNN was founded because the media was failing to report the positive news. In the 1990’s while homicide rates in the U.S. plummeted by 42 percent, television news coverage of murders surged more than 700%, according to the Center for Media and Public Affairs.”

SWNS
“Original. Verified. Engaging.
“…SWNS is proud to be supported by Digital News Innovation Fund (DNI) Fund, a European programme that’s part of the Google News Initiative, an effort to help journalism thrive in the digital age. Our syndication platform SWNS.rocks was one of the first projects to be awarded funding.”

An ‘up’ side I see there is that the folks at GNN apparently acknowledge that we aren’t living in the worst of all possible worlds. And SWNS either regards verifying what they hear as a good idea: or think that their subscribers feel that way.

So: on the whole, good news.

Plus, those “400 fossils” articles included specific details. Those details helped me find what Dr. Farid Saleh and others wrote about the Cabrières Biota.


Welcome to the Cabrières Biota

Christian McCall's/Prehistorica Art's illustration of the Cabrières Biota, detail. (2024?) via ResearchGate, used w/o permission. 'In the foreground, a row of Ampyx (trilobites). Behind the trilobites, a lobopodian....'
Christian McCall’s illustration, detail: trilobites and a lobopodian. “The Cabrières Biota…”, Figure 6

Christian McCall's/Prehistorica Art's illustration of the Cabrières Biota, detail. (2024?) via ResearchGate, used w/o permission.What first caught my eye about that illustration was the conga line of spiny critters in the foreground. I’ll get back to them, after this caption from the Farid Saleh and company paper.

The Cabrières Biota (France) provides insights into Ordovician polar ecosystems
Farid Saleh, Lorenzo Lustri, Pierre Gueriau, Gaëtan J-M Potin, et al.
Nature Ecology & Evolution (February 2024)

Fig. 6 | Artistic reconstruction of the Cabrières Biota. In the foreground, a row of Ampyx (trilobites) and various shelly organisms, including brachiopods and a hyolith (bottom left corner). Behind the trilobites, a lobopodian, a chelicerate, cnidarians (blue), sponges (green), thin branching algae (red and green) and hemichordate tubes (purple), along with some molluscs. Bivalved arthropods inhabit the water column along with graptolites. Credit: Christian McCall (Prehistorica Art).”

Now, about those spiny critters. They’re trilobites: Ampyx trilobites. Ampyx is a genus of trilobites that survived the Late Ordovician mass extinction: which happened some 25, 000,000 years after these Cabrières Biota critters lived and died.

Scientists have found adult Ampyx fossils lined up more-or-less the way Christian McCall shows these: neatly lined up. Odds are very good that those trilobites were going somewhere in a conga line or peloton.1

Lobsters Do It, Maybe Trilobites Did It

We know that spiny lobsters line up in a peloton when they’re going somewhere.

Maybe Ampyx lined up because it helped them get from point A to point B. Or maybe they lined up as part of their mating routines. Since we don’t have living trilobites, Ampyx or otherwise, working out their behavior takes a great deal of data and analysis.

Lobopodians and Other Seriously Weird Critters

Farid Saleh et al.'s figure 4 a, b '...Incomplete armoured lobopodians UCBL-FSL713616 (b) and UCBL-FSL713617 (c) exhibiting two sclerite plates along an elongated soft body with annulations. A lateral extension in b possibly represents remains of the proximal part of a lobopod (?lo)....' (2024)
Incomplete fossils from the Cabrières Biota: armored lobopodians,

Exactly what Lobopodia, and Lobopodians, are depends on who you ask.

Basically, they’re Panarthropods, which — if the definition gets traction — is a clade including arthropods, tardigrades, velvet worms, and Burgess Shale critters like Opabinia and Hallucigenia.

A clade is a phylogenetic taxonomic category: and something I won’t even try discussing right now. I like science, big words, and definitions. But this week I’ll be doing well to show you some of the ‘gee whiz’ items I found.

A fair number of scientists call Opabinia, Hallucigenia, and other instances of Cambrian and Ordovician weirdness, Lobopodia: arthropod-worm-things with many pairs of more-or-less-squishy legs.

Some Lobopodians, like Cabrières Biota specimens UCBL-FSL713616 and UCBL-FSL713617, apparently grew armor on at least parts of their bodies.2

Cabrières Biota Fossils: What’s the Big Deal?

Björn Kröger's, David Evans' map of some fossil sites in France: from Fossil Record. (February 2011)
Some Cambrian and Ordovician fossil sites in France. (Björn Kröger, David Evans; 2011)
Farid Saleh et al. maps, showing location of Cabrières, France. From 'The Cabrières Biota (France) provides insights into Ordovician polar ecosystems', Nature Ecology and Evolution (February 2024)
Maps showing location of Cabrières, France. (Farid Saleh et al.)

Scientists who speak my language, English, call exceptionally well-preserved fossil deposits like the Burgess Shale and the Cabrières Biota spot in France a lagerstätte. Don’t bother trying to remember that. There won’t be a test.

The Cabrières Biota is, or was, back in the Ordovician, near where Cabrières Village is today: in the southern Montagne Noire, in France. If it was in Germany, it’d be Schwarzer Berg. Here in Minnesota we’d call it Black Mountain.

What’s outstanding about the Cabrières Biota fossils is that there’s almost 400 of them, and that they’re so well-preserved that scientists are finding traces left by soft tissue.

That, and that the rocks were very near Earth’s south pole when those critters were alive.3


Heraclitus and Life in a Changing World

Plate tectonic map of Middle Ordovician (plates position as of 472 Ma). Mollweide projection. Modified from Golonka (2012). 1 - oceanic spreading center and transform faults, 2 - subduction zone, 3 - thrust fault, 4 - normal fault, 5 - transform fault.
Earth’s continental plates 472,000,000 years ago, map by Golonka Jan and Aleksandra Gawęda.

“Everything changes and nothing stands still.”
(“πάντα χωρεῖ καὶ οὐδὲν μένει”, quoted by Plato in “Cratylus“)
(Heraclitus, Wikiquote)

Earth’s climate hasn’t been stable since the North American Craton was part of Rodinia. Neither, for that matter, have Earth’s continents.

One of these days, maybe I’ll talk about continental drift, plate tectonics, and what we’ve learned about Earth’s shifting surface since the mid-1960s. But not today.

Instead, I’ll just note that the core of North America used to be west of what would become Siberia, and both were on Earth’s equator. That was around 472,000,000 years ago, two million years before the Cabrières Biota left us those remarkable fossils.4

You’ll find “Siberia” marked on that map, next to the Paleoasian Ocean: but the North American craton is called Laurentia. I’m not sure why, and that’s another topic.

Ordovician Climate and Getting a Grip

Maps of from Extended Data Fig. 1 | Distribution of Ordovician Lagerstätten. 'The Cabrières Biota (France) provides insights into Ordovician polar ecosystems', Farid Saleh et al., Nature Ecology and Evolution. (February 2024) used w/o permission
Maps from “The Cabrières Biota…”, Extended Data Fig. 1 | Distribution of Ordovician Lagerstätte.

Dragons flight's chart: a half-billion years of climate change, based on oxygen isotope ratios. (2005)Anyway, both the NBC Right Now and Good News Network versions of Isobel Williams’ article say that the Cabrières Biota “was a place of refuge for animals escaping global warming”.

In a way, they’re right.

470,000,000 years ago, Earth was a lot warmer than it is now. But it had been even warmer 15,400,000 years earlier — give or take a few hundred thousand. Make that a lot hotter: compared to the ice age we’re living in.

Or maybe it’s the ice age that ended about a dozen millennia back.

I’d better explain something.

I don’t ‘believe in’ global warming.

I don’t ‘not believe in’ global warming.

Earth’s surface temperature has been going up, on average and in general, for the century or so that we’ve had instruments in place and been keeping consistent records.5 Some of that change probably came from large-scale coal burning.

Cleaning up the mess left by uncontrolled industrial processes strikes me as a good idea.

Having screaming conniptions over global warming, climate change, and the dreadfully dire threat of the other political party — profoundly does not.

Illustration from a review of 'The World Without Us', by Alan Weisman: 'New York City 15,000 years after people.' (2007) from urbanghostsmedia.com, used w/o permission.Maybe the current ice age really is the former ice age. The last I checked, scientists weren’t all convinced that we’re not in an interglacial period.

I know: double negative.

The point I’m groping for is that learning about Earth’s climate looks like a good idea. Maintaining a state of blind panic does not.

Back to critters that stopped living long before the 24-hour news cycle began.

Two Biota and Increasing Diversity

Farid Saleh et al., from 'The Cabrières Biota (France) provides insights into Ordovician polar ecosystems', Nature Ecology and Evolution (February 2024 ): 'Extended Data Fig. 3 | Taxonomic abundances in the Cabrières Biota and their comparison with the Early Ordovician Fezouata Biota. The Cabrières Biota showcases a notably higher abundance of algae and sponges, while echinoderms are remarkably scarcer in comparison to the Fezouata Biota. Other animal taxa display relatively comparable representation between the two Lagerstätten. It is important to note that this data is highly probable to evolve with forthcoming fossil discoveries. Hence, it should be used only as an initial comparative reference. The Fezouata Biota dataset derives from the Marrakesh collections.'
Comparison: taxonomic abundances in the Cabrières Biota and the Early Ordovician Fezouata Biota.

The Ordovician geologic period lasted some 41,600,000 years. Quite a bit happened during that span of time, but I’ll try summing it up in a few sentences.

Scientists define the Ordovician’s beginning as the Cambrian-Ordovician extinction event. Basically, a whole lot of critters died when Earth’s ocean ran low on oxygen. Sea level changed, too. But life went on.

Our name for the Ordovician’s first stage is the Tremadocian. It was really hot, but Earth was cooling off: and would keep cooling during the rest of the Ordovician.

Next came the Floian stage, which was transitioning into the Dapingian when the Cabrières Biota was current events.

Again, never mind these names, there won’t be a test. I’m mentioning them mainly because the Cabrières Biota paper mentions the Fezouata formation.

Fossils from the Fezouata formation formed during the Tremadocian and Floian.

The Fezouata formation fossils — try saying that fast, five times — are lagerstätte. Very well-preserved, in other words.

A couple more words: biota and biome. I gather that in this context, a biota is the plant, animal (and presumably other) life that’s in a particular spot: along with the geology, weather, and other aspects of that spot. A biome is pretty much the same thing.

Farid Saleh et al.’s “The Cabrières Biota…” focuses mainly on describing the fossils.

That’s a vital first step in analyzing the things. They’re the next best thing to having photos and samples from that biota when the critters were alive.

Data from places like the Cabrières Biota and Fezouata formation will help scientists piece together what was happening during the Ordovician.

Assuming that those two points were more-or-less ‘normal’ for their time, it looks like life was getting more diverse back then.6

Gradual Cooling, Occasional Meteor Showers, and an Ice Age

Major trilobite clades summarized. Figure 6, 'The Evolution of Trilobite Body Patterning,' Nigel C. Hughes, Annual Review of Earth and Planetary Sciences (2007)As Heraclitus said, change happens.

About 2,500,000 million years after those Cabrières Biota fossils formed, there was a sharp uptick in the number of L chondrite meteorites hitting Earth. Oddly enough, an extinction event didn’t happen then.

Not that we’ve found, at any rate.

Earth kept cooling off. Then, about 460,000,000 back, another ice age began. Scientists are still debating why glaciers started grinding across our world that time. Might have had something to do with dropping carbon dioxide levels.

Earth’s sea level dropped, too. And so did ocean oxygen levels. Small wonder so many critters stopped living. Toxic metals leaching out of the sea floor, another effect of insufficient oxygen, wouldn’t have helped.

I haven’t dug into it, but at least one physicist said that maybe a hypernova went off near us back then. A hypernova’s gamma ray burst would have played hob with anything near the surface on the side of Earth facing the event.

The hypernova idea is still in play, but hasn’t gotten all that much traction.

Knew I forgot something. Volcanic eruptions. There was an uptick in those: so maybe volcanic sulfur in our atmosphere helped cool things off. Then again, maybe not.

There’s a possible asteroid impact involved, too.

What can I say? Earth is not a serenely unchanging place.

But life kept going. Including, after the Late Ordovician mass extinction, trilobites.

Trilobites thrived throughout the Silurian and Devonian. It took the Great Dying to end them: although they were on the skids by that time.7


Living in a Vast and Ancient Universe

Notary137's photo: Grand Canyon National Park; Indian Garden and Three-mile Resthouse viewed from Bright Angel Trail. (April 22, 2006) via Wikipedia, used w/o permission
Grand Canyon: part of Bright Angel Trail. Photo by Notary137 via Wikipedia, used w/o permission.

Bill and Jeff Keane's 'Family Circus' at the Grand Canyon: a river, a ranger, God and a good question. (August 14, 2021)It’s late Friday afternoon as I write this.

So instead of repeating what I’ve said about being okay with God being God, and not getting upset over the Almighty’s design aesthetic, I’ll repeat what I’ve said about living in this vast and ancient universe.

I like it. I like it a lot.

And I enjoy living in an era where much of the science I learned in school turned out to be just part of a much larger puzzle.

I think it’s been about two and a half years since I talked about God, truth, secondary causes and being human.

Basically, it’s like Pope Leo XIII said: “truth cannot contradict truth”.

If I think God is God, that God creates everything we can see, and that God isn’t a liar: NOTHING we learn about God’s universe can get in the way of an informed faith.

Granted, learning something new often involves reviewing our preconceived notions.

And — yeah. I’ve talked about this sort of thing before. Often:


1 Trilobites, lobsters, an old behavior and a new research paper:

2 Lobopodia and other words you’ll almost never hear in casual conversations:

3 Where to find the Cabrières Biota:

4 Parts of Earth’s long story:

5 Weather, climated, adn the occaional ice age:

6 Mostly miscellania:

7 End of the Ordovician, but not the end of trilobites:

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About Brian H. Gill

I was born in 1951. I'm a husband, father and grandfather. One of the kids graduated from college in December, 2008, and is helping her husband run businesses and raise my granddaughter; another is a cartoonist and artist; #3 daughter is a writer; my son is developing a digital game with #3 and #1 daughters. I'm also a writer and artist.
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