At the end of the 1960s, while the
superpowers of our planet were
preoccupied with escaping Earth's
gravity and reaching the moon, 900
million km away, a small, distant comet
fell foul of a much larger gravitational
force.
The 5 km wide body had probably been
flung inwards from the Kyper belt
surrounding the solar system. But
instead of spiraling around the sun's
vast gravity well, it passed close
enough to Jupiter to be captured in
orbit around the gas giant. From then
on, the comet's fate was sealed, but it
would be another 2 and 1/2 decades
before it eventually met its end.
Schumag Levi 9 was named after the
scientists who first spotted it in 1993.
But by then it was no longer a single
icy body. It had already broken up into
a series of fragments, ranging from
hundreds of meters to up to 2 km across.
Simulations revealed that the comet had
been ripped apart by Jupiter's gravity a
year earlier when its orbit had brought
it within just 40,000 km of the gas
giant's cloud tops. The next orbit, the
researchers predicted, would bring the
pieces on a collision course with the
planet.
And so in July 1994, under the watchful
eye of ground and space-based
telescopes, the pieces of Shoemaker Levy
9 impacted Jupiter at over 200,000 kmh.
Over a period of 6 days, there were 21
separate impacts, releasing energy
equivalent to 6 million megatons of TNT.
Each collision producing a fireball that
rose up to 3,000 km above the Jovian
clouds.
And despite the gas giants fluid out of
surface, the scars from the impacts
remained visible on Jupiter's surface
for months after the event. The largest
of these scars was almost the same
diameter as the entire Earth. And for a
time, they were more visible than the
planet's famed red spot. Indeed, for
many years after, Jupiter experienced
chemical and structural changes as a
result of the comet's near miss and
eventual demise. Within the planet's
atmosphere, new chemical species were
produced by the violent collisions and
persisted for many years. The changes to
Jupiter were surprisingly prominent and
long-asting considering the small
original size of Shoemaker Levy 9. The
fact that the comet didn't impact
directly onto the surface, but instead
experienced a near miss undoubtedly
helped to shape its eventual impacts.
But what if the interplanetary traveler
had been larger or denser? What if it
had approached from an angle that would
have preserved its fragmented orbit for
longer? Then we might not have witnessed
the destruction of a satellite, but
rather the genesis of a new ring system
around Jupiter. It may seem far-fetched,
but this is almost certainly how Saturn
obtained its rings less than 100 million
years ago. And there is growing evidence
that our own planet turned a near miss
into a glittering accessory, at least
for a time, some 450 million years ago.
And the story of how the earth came to
have rings, what happened to them, and
what they did for our world is a tale
that spans tens of millions of years,
almost the entire orivision period, and
may well have changed the course of
animal evolution forever.
[Music]
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[Music]
For the residents of Barwell in
Leicester in England, Christmas 1965
came with a bang followed by a thud and
thousands of pounds worth of damage.
It started, appropriately enough for
Christmas Eve with a bright light in the
sky. But this star didn't hang in place
for long. It strear
that heralded its coming with a
shuddering sonic boom. Moments later,
countless bangs and crashes sounded
across the village and surrounding
fields as the Christmas visitor fell to
Earth.
But this was no heavenly messenger. It
was a meteor which had traveled millions
of miles before tearing through the
Earth's atmosphere and breaking into
hundreds of pieces. Shortly after the
brief sound and night show, carol
singers making their way through the
town noticed gravel-sized pieces
crunching under foot, but thought
nothing of it. It wasn't until the sun
rose on Christmas morning that the
extent of the meteorite fall was
revealed. Fragments of rock had crashed
into the tarmac, leaving pits and
craters behind. One piece even smashed
into a brand new car. And when the owner
tried to claim for the damage on his
insurance, the company told him they
couldn't pay since it was caused by an
act of God. Soon, word got out about the
remarkable rockfall, and over the next
few days, Barwell was inundated with
people hoping to find a piece of fresh
space rock for themselves. Money was
offered for meteorite fragments, and
Barwell experienced its own mini gold
rush for this exotic rock. All that
searching helped to confirm the Barwell
meteorite as the biggest ever seen to
fall in the UK. In the end, more than 40
kg of space rock was recovered from in
and around the village originating from
an asteroid which predated the Earth
itself at around 4.55
billion years old.
Of course, today finds like this are
rare and valuable. Indeed, a nearly 1
kilo chunk fetched £8,000 in auction in
2009. But there was a time in our
planet's history when rocks just like
the Barwell meteorite may have been
much, much more common.
The Thorsburg quarry near Kinukle in
southern Sweden produces fine limestone
for flooring, tiles, and architectural
stone. The rock dates to the Order of
Vision when calcium carbonate
precipitated out onto the warm tropical
sea floor. But in 1988, workers at the
quarry found something unexpected when
they sliced open their reddish rock.
Alongside the usual Shelly fossils,
there was a large chunk of a different
kind of stone. Blackish green with a
glassy flaked outer edge. Geologists
soon realized that this intrusion was as
exotic as they come. It was a fossil
meteorite, just like the pieces that
rained down in Barwell, except this rock
had fallen while the Thorsburg limestone
was still being deposited 467 million
years ago. This remarkable discovery
sparked a search for more of the same.
And over the next decade, researchers
found a total of 40 fossil meteorites in
this quarry alone, over an area barely
larger than a football field. Unlike the
barwell rocks, which are numerous
because they all came from a single
fragmented meteor fall, these space
rocks were scattered through the
different strata of the Thorsburg
limestone without any evidence of the
meteorites having been eroded out and
redeposited.
And dating of the limestone layers
surrounding the exotic rocks show that
they fell at various times over 2
million years in at least 12 separate
rockfalls.
The majority of them are small and
together they total less than 8 kg. But
it is their sheer concentration that
makes them remarkable. At current rates
of meteor fall, you wouldn't expect more
than one or two rocks in an area the
size of the Thorsburg quarry. So to find
40 meteorites in just 2 million years,
something out of the ordinary must have
happened.
And not only that, but every single
extraterrestrial rock trapped in the
Swedish limestone appears to have the
same original chemistry.
In general, meteorites are classified as
one of three bulk compositions.
Iron thought to be derived from the
cores of ancient planet tessimals.
Stony, derived from those planetesses
crusts and mantles, or from smaller
rocks that never developed an iron core.
and stony iron which are a combination
of the two coming from the core mantle
boundaries of now destroyed
planetessimals.
Among the stony meteorites there are
finer subdivisions distinguished by the
texture and chemistry of the minerals
that make up those extraterrestrial
rocks and among those the so-called
condrites are the most numerous. They
are made up of tiny fused spheres which
represent individual droplets of
solidified rock which accreted early in
the solar systems history. The condrites
themselves are further distinguished by
how much iron they contain. Iron rich
specimens are called H condondrites for
high iron while L condrites have low
concentrations of iron between 4 and
10%. And the chemical similarity of
these rocks, regardless of where or when
they are found, implies that they all
originated from the same place. In fact,
scientists consider it likely that they
all originate from the same original
asteroid or planet. Indeed, today around
80% of all meteorites that fall to Earth
are L condrites, as was the Barwell
meteorite and the distributed orivision
rock falls.
And so all of this evidence points
towards a startling conclusion. All of
these rocks may be the lingering debris
from an ancient cataclysm that saw an
entire planet shattered into millions of
pieces.
This planet dubbed the El Condrid planet
would have begun much like our own
roughly 4 and a half billion years ago.
In a thin disc around our sputtering
newborn sun, dust consolidated into
grains which accreted into first
pebbles, then boulders and ultimately
into planet-sized rocks that became
rounded by their own rotation. Among
these would have been the Earth, Venus,
Mars, and Mercury, as well as Thea,
which would ultimately collide with the
Earth to create the moon. But there must
have been countless other rocks and baby
planets swinging around the sun on
chaotic orbits, tugged this way and that
by the shifting gravity of their larger
cousins. The early solar system was a
dangerous place for a baby planet, and
impacts between these semiolton
planetessimals would have been common.
like water balloons colliding midair.
Their combined momentum would have sent
droplets of iron depleted molten rock
spraying through space where those
droplets would freeze, accrete, and
begin the process all over again.
Indeed, it was only after a few more
million years when the hottest
radioactive elements became depleted
that the final accretions of molten
droplets wouldn't have remelted.
Instead, the frozen droplets kept their
shape as condrils and became fused
together, at least in the planet
decessimal's outer layers. 100 million
years afterwards, the small L condrite
planet with its grally texture and
uniform chemistry belying its tumultuous
past would have cooled sufficiently and
found a safe enough orbit for it to
stand the test of time.
And so we think it remained for roughly
the next 4 billion years.
But of course, nothing is safe forever
because around 500 million years ago,
this unassuming planet met a
catastrophic end
whose effects would be felt across the
inner solar system.
Scientists believe that the El Condrite
planet would have resided somewhere
between the orbits of Mars and Jupiter
within what is now the asteroid belt.
However, as the giant planet Jupiter
lunges around the sun, its gravity can
fling smaller objects off upon
unpredictable orbits, wreaking havoc in
collisional chain reactions. This is how
many asteroids in the belt came to be
and is the source of much of the
interplanetary debris that clutters the
inner solar system today. The Alcondrite
planet would have done well to avoid
this fate for 4 billion years, but it
eventually succumbed and either the
whole planet Tessimal or many of its
fragments were hurled inwards towards
the Earth.
And had this ancient planet or one of
its larger fragments collided directly
with the Earth, the result would have
been catastrophic. Similar to the
dinosaur killing impact at the end of
the Cretaceous.
But we see no extinction event, no
single calamitous episode in the
planet's geological record. Instead, it
seems the Earth received a drawn out
pummeling.
The Thorsburg limestone records a pulse
of small scattered meteorites. All of
the same composition but spread out over
2 million years. And this isn't the only
evidence of impact from this time. All
around the world, the researchers find
fossil impact craters that suggest that
during the early Order of Vision, the
flux of space rocks to Earth was 10 to
100 times higher than it is today. And
it wasn't just full-sized meteorites
either. Micrometeorites are constantly
raining down on our planet. Unnoticed,
but for the characteristically
extraterrestrial particles, they scatter
like salt through accumulating
sediments. Like their larger
counterparts, the flux of
micrometeorites is relatively constant
through time. Except throughout the
Order of Vision, it was as much as
10,000 times higher than at any other
point in history. This comparatively
torrential rain of space dust began
around 467 million years ago and lasted
albeit diminishingly for some 30 million
years.
Now, the key thing to know is that the
way extraterrestrial material is
delivered to Earth hasn't changed over
the last 500 million years, and there is
no known mechanism that can keep sending
meteors and their associated debris
across interplanetary space so
consistently and for so long. Not only
that, but the drizzling bombardment that
our planet received does not seem to
have affected our planetary neighbors.
Naturally, our sampling is limited, but
there is no conclusive evidence of
orivision age cratering or meteoritic
bombardment on either the moon or Mars.
If meteorite material had been flung out
of the asteroid belt and in towards the
inner solar system, then of course
there's an even chance of that material
hitting any of the planets within that
neighborhood. That only the Earth should
be affected while the other bodies were
spared seems vanishingly unlikely.
How then are we to explain the uniquely
targeted but drawn out assault that our
planet received throughout the Order of
Vision? It is clear that there must be
another twist at the end of the El
Condrite planet story.
And in solving this mystery, a crucial
piece of evidence came to light in 2024.
The 100fold increase in meteorite falls
during the period in question means that
there are some 20 or more impact
remnants preserved from this time in
locations ranging from modern-day Canada
to Australia, India, and northern
Europe. Today, those locations are
scattered across the globe. But when
researchers reconstructed plate motions
over the last 450 million years to map
the position of the orivision
continents, they revealed a remarkable
pattern. These impact craters weren't
distributed randomly as you might expect
from an interplanetary bombardment
originating in the asteroid belt.
Rather, they were concentrated in a band
around the equator.
And it is this along with the other
seemingly inexplicable features of the
Orivision meteorite bombardment that has
led scientists to a single surprising
conclusion.
All of this meteorite material was
derived from a ring of rock and dust
that encircled the Earth.
[Music]
And so this may well have been the fate
of the El Condrite planet.
[Music]
Either the whole planet or a large
fragment of it would have been launched
out of the asteroid belt by the orbital
chaos within that region of space. It
crosses the interplanetary distance,
making a direct line for the Earth. But
instead of colliding, it misses by the
narrowest of margins. Had it been
further away, the fragment may have been
captured and ins snared into orbit as a
second moon, similar to how Mars
acquired its two moons. But in this
scenario, the Elondrid fragment comes
closer. So close, in fact, that the
Earth's gravitational forces rip it
apart, just as Jupiter had done for
Shoemaker Levy 9.
Orbital calculations place the
Elcondrite planets near miss at
somewhere less than 15,000 km which is
less than 4% of the distance to the moon
and well within the orbits of our modern
geostationary satellites. The breakup of
the rocky planet Tessimal would have
left behind a scattered field of debris
spinning around the planet with its
original momentum forming a ring system
like that which adorns Saturn today. The
difference is that this ring would be
made of rock rather than ice and would
be somewhat more compact like the
missing Saturn's ring's characteristic
stripes. Over the next 40 million years
or so, the pieces that make up the ring
would slow and descend, caught by the
Earth's tenuous upper atmosphere and
de-orbiting like decommissioned
satellites.
Meteorites large and small would rain
down as ever so gradually the rings
disintegrate and fall to Earth.
While they would have persisted,
however, the sight must have been a
spectacular one.
From the surface, a darkened arc of dust
and debris would hang motionless in the
sky, shading the sun during the day and
reflecting it during the night, lighting
the night sky in a way similar to, but
more intensely than the full moon.
At the equator, the ring would be barely
visible as a thin line passing directly
overhead. At the poles, it would hug the
horizon. But in the middle latitudes,
the debris ring would permanently
dominate a large swave of the sky,
changing only as the Earth's shadow
swept across its surface.
This all may seem like science fiction,
but at the moment, it is the only
explanation that scientists have found
to tie together all of the conflicting
meteorite evidence from this time.
Accessorized with a rocky debris ring,
our planet would have looked remarkably
alien, even while the ancestors of all
living animals and plants thrived on its
surface. But a closer look at the
geological record reveals that the
surface of the planet itself was far
from familiar.
[Music]
In ways both unrelated and also perhaps
heavily influenced by the planet's odd
cosmic events. Throughout the orivition,
the Earth was also experiencing one of
its most extreme and bizarre phases.
A phase that would have rendered the
planet at the center of those rocky
rings all but unrecognizable.
[Music]
The wind was the first to arrive.
Palm trees whipped and bent at
infeasible angles, while the branches of
tropical hardwoods and pines were ripped
from their trunks and sent crashing
through the village. Rain fell and soon
became a deluge, turning the red earth
underfoot to sticky mud and submerging
everything as water pulled faster than
it could drain. Houses were cut off from
one another and the souls who huddled
inside them isolated by several feet of
rushing water hammering past their
doors. Sails furled, lines tort, and
cargo strapped with every available
piece of rope as the three wooden ships
morowed offshore were tossed about like
toy boats. Gradually at first, and then
all at once, Christopher Columbus'
flagship disappeared beneath the
tempestuous waves.
[Music]
When Columbus set out to discover the
Americas at the end of the 15th century,
he was already an accomplished seaman,
but he couldn't know what awaited him on
the other side of the Atlantic Ocean.
Throughout his initial voyages, the
explorer and his fleets visited the
Caribbean islands, including Hispanola,
home to modern-day Heiti and the
Dominican Republic, where he encountered
the native Tino people, and set about
establishing Spanish settlements to
stake the nation's claim on the
discovered lands. But the Tino knew much
about their homelands, the Columbus did
not. And while he could only helplessly
watch as two of his three ships
shattered and sunk, the natives had long
abandoned the coast and retreated to the
mountains. They had recognized the signs
of the oncoming storm, which they
attributed to their vengeful god,
Huracan, and had sought shelter far
inland. But to his credit, Columbus
swallowed his pride and took the lesson
from the Tino. And 7 years later, when
his fleet was passing the new settlement
of Santa Domingo, he saw the changes
they had taught him to watch for. A
reddened sun, higher swells on the sea
and the irregular behavior of animals
more sensitive to the natural
environment than man. Columbus sailed
his ships to the west of the island to
protect them from the worst of the
storm. But another Spanish fleet was not
so lucky. When the storm struck the next
day, the Tino's guard claimed 25 of
their 30 treasure laden ships along with
the lives of 500 sailors and untold
numbers of slaves.
The wisdom of the Tino came from their
experience. Since the island of
Hispanola along with all of the
Caribbean islands have weathered storms
like this since there have been islands
in this part of the world. Their god
Huracan eventually gave its name to
these uniquely destructive storms in the
northern hemisphere and hurricanes
continue to shape the history of the
western Atlantic. Warm temperatures over
the tropical ocean, combined with
large-scale circulation within the
atmosphere, conspire to brew unstoppable
spiraling storms that wreak havoc across
all that stand in their path. Island
nations are especially cruy affected
since their small land masses do little
to diminish the storm's energy. And
indeed, as global temperatures continue
to soar in modern times, even the Tino's
wisdom may not be enough to withstand
the fury of Hurricane.
[Music]
And yet, however destructive the
Atlantic hurricanes may become, they
will pale in comparison to the tempests
that ripped across the Earth beneath the
shadow of its transient rings 450
million years ago.
By this point in the earth's history,
the stable centers of many of our modern
continents were already established. The
large continent of Gonduana dominated in
the southern hemisphere stretching from
the equator to the south pole and
containing much of what is now Africa,
South America, Antarctica, and
Australia. The rest of the continents,
Lentia, containing modern-day North
America, Baltica, and much of northern
Europe, and Siberia, now found in the
center of Russia, was still distinct,
separated from Gonduana by some 8,000
km. The Paleotethis Ocean lay in
between, about twice the width of the
modern Atlantic, but also studded with
many smaller islands around the edges of
the larger continents like the Caribbean
with large. These so-called ribbon
microcontinents were a product of the
state of plate tectonics during the
orivition.
Plates move over the earth's surface
constantly. Sometimes their slow
grinding movements crush continents
inexraably together. Other times land
masses are mercilessly ripped apart. But
around 450 million years ago, all of the
action was taking place in the oceans.
At some distance from the existing
continents, ocean crust subducted
beneath ocean crust. Trapped water was
released from buried slabs of rock,
causing the crust above to melt,
creating magma, which itself rose up and
created new volcanic islands parallel
with but just behind the subducting
ocean trench. All along the trench, new
island formation took place, forming an
interrupted ribbon of land mirroring the
larger continental edges.
But with all land masses together south
of the equator, there was nothing but
featureless blue to the north. Ocean
reign supreme.
Winds blew uninterrupted, diverted only
by the corololis forces from the
spinning globe itself. And beneath the
surface, water currents followed suit.
This pantholacic ocean was one of the
Earth's great super oceans, covering
more than half of the globe, nearly
double that of the Pacific Ocean today.
Embarking north from the equator, an
ordivision submarine could travel some
20,000 kilometers under the sea, passing
across the pole before they encountered
land again.
From the vantage of the planet's
encircling ring, then the Earth would be
a world of two halves, split almost
perfectly by that alien rocky suthe. To
the south, a tropical paradise of
sparkling turquoise seas dotted with
islands and smoothedged continents. To
the north, an empty expanse of deepest
darkest blue, whipped into huge swells
and cabbed with white spray, but with no
shore to break those towering waves.
It's likely, however, that little of
this remarkable vista would have been
visible for long, for yet another swing
of the Earth system pendulum conspired
to make our planet appear utterly alien.
Throughout this period,
building the ribbon microcontinents that
edged the larger land masses required
immense quantities of lava discorgged
from the boughels of the earth to flow
over the sea floor and over previous
flows until it eventually breached the
water's surface to create new land.
But molten rock wasn't the only thing
that these volcanoes produced. With
every eruption and even between
eruptions, the volcanic vents poured
tons and tons of invisible carbon
dioxide gas into the atmosphere. And
there it behaved just as it does today,
acting as a greenhouse gas, trapping
incoming solar radiation and swaddling
it close to the surface, heating the
air, water, and land surfaces alike.
Indeed, the Lake Cambrian and early
Oivision saw so much volcanism that
atmospheric carbon dioxide levels
soared, reaching levels higher than at
any other time in the Fanneroic,
including today. With around one in
every 200 molecules in the atmosphere
being carbon dioxide, concentrations
were some 15 times higher even than the
modern post-industrial Earth.
[Music]
And so just as high concentrations of
greenhouse gases today are contributing
to elevated global temperatures and
unpredictable climate, these extreme
carbon dioxide levels would have sent
temperatures soaring throughout the
early orivition.
Researchers estimate that on average
surface temperatures reached 10° C
higher than today. No ice could have
survived under such sweltering heat,
even at the poles. And any water that
could have been sequestered there now
flowed freely into the oceans, boosting
sea levels and flooding continental
shelves. Around the new volcanic islands
of the continental fringes, shallow
sunlit seas were as warm as bath water.
But despite this, in reality, this was
no tropical paradise.
Heat translates to energy in the
atmosphere, which must find an outlet
somewhere within the claustrophobic
shell of the planet's surface. Under
such high temperatures, water evaporates
from the sea surface at a terrifying
rate, stuffing the troposphere with
water vapor, building towering
thunderclouds and raising the humidity
to a stifling swelter. Torrential rain
falls daily, but offers little relief
from the torid, sticky heat. Winds blow
constantly, gusting from high to low
pressure systems formed by the
large-scale circulation of the
atmosphere. And more heat means more
energy, which means ever more powerful
winds.
And the hemisphere spanning panthalic
ocean only served to reinforce the
atmospheric tumult and brew perfect
neverending storms across its surface. A
seemingly endless expanse of water and
uninterrupted corololis winds whipped
storm clouds into cyclones thousands of
kilome wide. And with no land on which
to release, these hurricanes build and
build, tracking diagonally across the
globe until eventually hitting higher
latitudes, cooler water, and calmer
conditions.
Near the equator, however, where the
young volcanic islands lie, amid shallow
seas within the maelstrom's path, the
bombardment would be relentless.
Like the Caribbean islands, they would
be exposed to the full force of the
oncoming hurricanes, but would offer
little in the way of resistance or
moderation. The storm surges churn up
the bottoms of their sandy seas,
triggering devastating underwater
landslides before hurling and stranding
water, mud, and marine debris far
inland. And the storms keep coming. For
millions upon millions of years,
hurricanes whip around the globe under
the eerie shadow of a dusty planetary
ring.
This was particularly dangerous
territory for an unbalanced climate
system. With temperatures so high, there
was a real risk of positive feedback in
the Earth system, causing a runaway
greenhouse effect and sending the planet
into an inescapable heat spiral. High
temperatures evaporate more water,
filling the atmosphere with heat,
trapping water vapor and boosting
temperatures further until rivers,
lakes, and eventually the oceans
evaporate away. Indeed, it's likely that
something like this happened to our
planetary neighbor Venus. Being situated
that much closer to the sun made it
easier for greenhouse conditions to turn
critical. But thankfully, however, this
wasn't to be the fate of the orivision
Earth. Despite the colossal carbon
dioxide concentrations,
instead of rising out of control, carbon
dioxide levels and temperatures actually
fell throughout this period. And
scientists believe we have the sun's
youth to thank for our savior.
480 million years ago, the sun gave out
approximately 4% less light and heat,
meaning that there was much less
radiation available for the greenhouse
gases to trap, therefore keeping the
temperature rise extreme, but not
inescapable.
There were other factors at play, of
course, among which the planet's rings
were almost certainly a significant
part. The shadow that this rocky band
cast would have changed throughout each
day from season to season and across the
millennia. But its cooling embrace delus
had a tangible influence on the global
climate and on the conditions that
rained down on the surface.
And that was not all it did. As well as
preventing a runaway climate
catastrophe, the orbiting fragments of
the El Condrite planet may well have
seeded a lasting change on Earth's life
as well. For over the course of the
Orivision period, it's likely that our
alien rings had a guiding hand in one of
the Fanneroic's biggest booms
and one of its biggest crashes.
[Music]
Sometime in the Lake Cretaceous, a
fireball streaked across the sky and
struck the Earth.
But this wasn't the city-sized rock that
would bring a cataclysmic end to the
dinosaurs. This was a more modest 1 and
1/2 km wide asteroid fragment that
impacted what would become southern
Finland. And though it may not have been
enough to bring about a global
catastrophe, it was certainly capable of
doing serious damage to everything
within its fateful reach. At the moment
of impact, rock was liquefied and
vaporized, experiencing temperatures of
up to 15,000° C and instantaneous
pressures equivalent to that found at
the center of the Earth. The asteroid
itself was obliterated, and the
collision carved out a crater some 23 km
wide and more than 700 m deep. All
around the impact site, the coniferous
forests were flattened and set a light
as a scorching fireball spread out from
the center. Bucklas dinosaurs, mammal
ancestors, and insects alike were
burned, battered, and buried by debris.
When the dust eventually settled and the
smoke cleared, the crater and its
immediate surroundings were left sterile
and steaming. No living thing, not even
a microbe, survived this local
cataclysm. Even as the seasons changed,
it would be nearly a million years
before this scar in the earth cooled
enough for liquid water to remain.
Then a lake began to pool in the basin,
fed by rain and groundwater, but still
hot and chemically corrupted by the
altered rocks at its base. Nevertheless,
life found a way back into the cratered
wreckage. First came the microorganisms
that could withstand high temperatures
and acidic waters. Hydrothermal microbe
communities, similar to those found
around hot springs, could have turned
the crater lake a rainbow of colors as
they manipulated the water chemistry to
their own ends. Over time, temperatures
in the water cooled enough for the heat
tolerant organisms to be replaced by a
more cosmopolitan community. Spores and
pollen blown on the wind from
surrounding vegetation helped heal the
broken baron ground with fungi, lyken,
and mosses, and the soil they could
create.
At first, the lake and its shores were
tough places to ek out in existence, but
more soil meant larger plants, grazing
animals, and a succession of complex
ecologies. Richer organic soils leech
nutrients into the greater lake, it
becomes capable of supporting large
populations of fish.
But this succession does take time.
Thousands or millions of years may pass
before the scar fully heals. And the
ecosystem it hosts will always be
different from that around it.
And this is a pattern that intelligent
animals, humans are able to exploit. The
greater lake later becomes a hub for
bronze age hunters who seek the animals
that are drawn to the productive
watering hole. And thousands of years
later, it is still a hub. But now for
other human visitors seeking to enjoy
the natural pleasures this diverse
landscape offers. The town of Laayavi
grows on the lake's northern shore,
supporting tourism and fishing, while
the fertile soils of the diverse
surrounding area are plowed for wheat,
rye, and potatoes. In the winter, skiers
visit, riding a ski lift that ascends
the rim of a 77 milliony old impact
crater.
[Music]
And none of this would have been
possible without the late Cretaceous
impact. Had the rock not struck the
earth, then this region of central
Finland would have remained unaltered
ancient Taigga forest without any of the
biological and anthropological richness
that it now boasts. And so the impact
may have been a calamity at the time,
but wiping the slate clean and starting
a fresh allowed a more varied and
productive ecosystem to grow in its
place. In this way, impact events are
unique. They are some of the only
mechanisms capable of disrupting an
ecosystem locally in both space and
time. Crater forming collisions of this
size aren't large enough to affect the
global environment, but they can make a
big difference on a local or regional
scale. Statistically, however, they
don't happen often. Impacts like this
can be expected somewhere on Earth every
2 million years or so. But 450 million
years ago, in the order of vision, such
targeted ecosystem engineering would
have been much more common thanks to the
planet's encircling ring.
The extraordinarily high temperatures at
the beginning of the orivision meant
that none of the Earth's water was
trapped in ice shelves or ice caps and
instead topped up the ocean reservoir.
This combined with the low relief of new
volcanic islands meant that sea levels
were at their highest point for several
hundred million years and only continued
to rise throughout this period. Water
flooded the vast continental shelves,
creating warm, shallow seas all
throughout the southern hemisphere that
were just a few hundred meters deep.
This was a tropical paradise for marine
life, of which the Udivision boasted
plenty. The shelves surrounding each of
the smaller continents created distinct
and separate habitats, allowing seafloor
communities to adapt and diversify in
response to the unique conditions each
one offered.
As a result, the udivision period played
host to one of the most remarkable
periods of biodiversification of the
entire phenorizoic.
The Cambrian explosion some 40 million
years earlier had seen the invention of
most of the modern animal filer. At this
time, the major animal divisions were
carved out based on fundamentally
different body plans. The arropods,
cordates, ainoderms, molllesks among
others. taking their places on the stage
of life.
For example, the trilobytes who could
trace their heritage back to the early
Cambrian had come into their own by the
orivision.
They diversified into nearly 5 12,000
species within 56 families distributed
unequally around the planet and adapted
to an astonishing range of specialized
lifestyles and habitats.
New forms had highly developed eyes on
stalks, pillars, and with shaded brows
to help them perceive danger all around
in the water column. Many trilobyte
shells became better articulated,
allowing the creature to bend and flex,
which would help with both defensive
poses and swimming through open water.
And numerous other species developed
spines, knobs, and other ornaments
around their shells, which may have
helped with sensing, giving traction in
soft sediments, or even as a deterrent
to predators. All of this helped them to
succeed in a wide variety of marine
environments.
And indeed, they weren't alone.
As well as this dominant group of
arthropods, there were plenty more
diverse and disperate marine groups on
the sea floor and in its waters. Large
biologically constructed mounds called
bioerms grew where ocean currents,
nutrients, and sunlight favored them.
Constructed as they were from
overlapping growths of algae, sponges,
and colonial organisms called bryozones,
the ainoderms expanded to include many
branching kryinoids that rooted to the
sea floor or swam freely through the
water, as well as sturdy stemmed
blastoids, now extinct. A related group
of free floating hemicordates became
known for the chalk-like scrolls their
fossils seem to leave in slate and were
named graptalytes. As a result, they
thrived during the period with over 40
different species and molllesks
zealously joined the fry as well with
countless species of clams, snails, and
freeze swimming seephalopods appearing
and proliferating for the first time.
And alongside these invertebrates were
our own ancestors, too. Cordates defined
by a central cord of nerves that would
eventually manifest as a vertebrate
spinal column begin to appear
recognizably fish-like around this time
with eely connodons known mostly for
their teeth and the first bony fossils
of jewelless armored fish related to
hagfish and lampres.
[Music]
And so whether in the water, in the
seafloor, sediment, or anywhere in
between, the oceans teamed with
specialized life, the likes of which had
never before been seen on Earth. But why
did it happen then? What was so special
about this particular time? Oceans have
been warm, seas have been shallow, and
continents have been distributed at
other times in the Earth's history. But
those times have not seen the same
remarkable diversification that defined
the order of vision.
One explanation is related to the
relative immaturity of animal life
itself. Prior to this early stage of the
pharazzoic, there had been no mobile
macroscopic life to speak of. And so the
marine environment had spent the
preceding 4 billion years or so largely
untouched by the biology that inhabited
it. But that changed once animals
started moving around.
An influx of worms and other creatures
burrowing into the sea floor disturbed
chemical reservoirs for the first time,
mixing them up and ultimately altering
the chemical composition of the oceans
and atmosphere. It's thought that this
burrowing initially helped to release
oxygen from the sediments which would
have oxygenated greater expanses of the
oceans and offered more opportunities
for energetic biology. Indeed, during
the orivition, elevated oxygen levels
are correlated with periods of greater
diversification.
However, at other times in Earth's
history, pulses in oxygen haven't
necessarily seen such a boost in
diversity. So, this can't be the whole
story. Instead, researchers are
considering the possibility that this
unique phase of evolution could have
been driven in part by the planet's
unique accessory at this time, its rocky
ring system.
When the Elondrid body experienced its
near miss with the Earth, gravitational
forces and subsequent collisions would
have ripped it into countless fragments
that remained in orbit around the
planet. But these orbits wouldn't have
been stable over the long term. Air
resistance from the top of the
atmosphere, plus other chaotic
collisions within the ring itself, would
have caused pieces of rock to frequently
deorbit and come crashing down to Earth.
Indeed, it was these pieces that were
found in the limestones of Thorsburg
quarry, but we can expect there to have
been countless others. The larger among
them would have struck much like the
Finnish meteor during the Cretaceous,
carving out craters in the earth and
obliterating themselves in the process.
Like that Cretaceous impact, these
collisions would have wre havoc on the
local environment. Everywhere the rocks
struck, water would be vaporized, all
animal life eviscerated, and the crust
locally shattered and superheated.
[Music]
It would have taken thousands of years
for the area around the impact to
recover, but when it did, it would be
subtly different from the environment
that had existed before.
Perhaps the depth was slightly different
or the water chemistry or the way the
ocean currents flowed. But whatever the
difference, it created new opportunities
for the life that recolonized it.
In this way, the minor but persistent
impacts caused by de-orbiting rocks from
Earth's rings could have created a
patchwork of new niches for animals to
adapt to. The global environment wasn't
significantly affected, but existing
ecologies would have been constantly
disrupted, leaving survivors to start
again in new environments and forge new
paths to success.
There is evidence that the planet's ring
system persisted for some 40 million
years. And so, local marine ecosystems
could have been made and remade
countless times within this period. Each
new succession would create new species
which aren't entirely wiped out by the
next impact, resulting in an overall
biodiversity boom, the likes of which
has not been seen before or since.
[Music]
However, this storm of success was not
to last. While the rings may have been a
boon to biology in the beginning, they
may also have been instrumental to its
demise by the end of the uh division.
Because no sooner had this Paleozoic
biodiversity blossomed, it was struck
down once again. And to this day,
scientists aren't sure why.
Throughout the early Odivision, carbon
dioxide levels, temperatures, and sea
levels remained high. But abruptly
around 445 million years ago, CO2
dropped and global temperatures
plummeted, leading to a sudden
glaciation and oceanic changes that
would wreak havoc on the warm marine
Eden that had dominated for the last 40
million years.
Sudden cold temperatures caused ice caps
to grow over the part of Gonduana that
lay over the South Pole, sequestering
water as continental ice caused sea
levels to drop, draining the shallow
shelves at the edges of the land masses,
drastically reducing the habitats for
seafloor dwelling organisms. Even those
who were spared exposure to the air
would have found themselves subjected to
ocean waters far colder than they were
adapted to, as well as pulses of
suffocating anoxia as ocean circulation
changed.
[Music]
The result was catastrophic to the new
granular diversity of the orivision
seas. Shallow water foreigners were
especially impacted with many groups of
brachopods, trilobytes, brizzoans, and
kroidoids disappearing for good.
Overall, with around 85% of all species,
up to 60% of all generally
founded families becoming extinct, the
end or division mass extinction ranks
second in the so-called big five mass
extinctions in terms of the percentage
of marine families affected. Indeed, it
was twice as damaging as the dinosaur
ending extinction at the end of the
Cretaceous.
While the link between glaciation and
oxia and extinction is fairly clear,
what's less clear is the cause of the
glaciation in the first place. Some
researchers have suggested a natural
cycling of carbon dioxide through
weathering and volcanic output. But the
abruptness of the event causes problems
for this explanation. It may be that
biology had a role in its own demise,
but other scientists have invoked more
extraterrestrial influences to explain
this remarkable event.
[Music]
One theory suggests that the Earth was
hit by an energetic gamma ray burst
released by colliding black holes
somewhere close by within our galaxy.
These damaging cosmic rays could have
irdiated shallow water animals and
created a photochemical haze in the
atmosphere that brought on cooling and
glaciation.
But the evidence for such a dramatic
galactic event is lacking. And perhaps
we don't need to look so far a field to
find an alien agent of destruction.
Perhaps it was orbiting Earth all along.
The rocky debris from the break up of
the El Condrite planet would have
dispersed in a thin but wide ring around
the Earth. While this ring would be all
but invisible from the equator,
elsewhere on the planet, it would have
been a significant and constant feature
of the sky, following a similar arc to
that of the sun itself. As such,
depending on the ring's density, it may
have offered significant shading to the
surface below, helping to regulate some
of the greenhouse heating and
potentially eventually ushering in a
devastating ice age.
Of course, there's still much we don't
know about the ring system. How large it
was, how dense it was, and how it
evolved through time would all
significantly affect the degree of
shading and cooling it could cause and
consequently how big a role it played in
the Woodishian mass extinction. But the
timing at least seems to be consistent.
The heightened rate of Elondrite meteors
falling to the earth begins around 467
million years ago and the onset of the
Endor division glaciation and extinction
occurs more than 20 million years later.
It's therefore possible that a small but
consistent cooling effect could have
accumulated over that period to help
usher in the mass extinction.
And there is one further possibility.
Recently, researchers mapping the
gravitational field throughout
southeastern Australia found something
big and unexpected buried beneath the
surface.
Across a region some thousand km wide is
an area of dense compacted rock that
appears to have been created by a
gigantic planetary impact.
The Deniloquin mega impact structure as
it's known consists of multiple
overlapping crater rings surrounded by
hills that were wrinkled up by massive
deformation.
Overall, the structure is some 10 times
wider than the Chichelab crater left by
the dinosaur killing impact and would
have been created by a collision that
released as much energy as a 100 billion
megat tons of TNT, releasing
catastrophic global tsunamis and
sunblocking dust clouds. And while the
dating of the buried craters isn't
particularly precise, it does cover the
order of vision when the Earth's
presumed rings dominated and the ensuing
extinction.
And so is this deniloquin structure
related to the orivision glaciation and
extinction? And was it a fateful product
of Earth's transient ring system?
Perhaps a larger fragment that escaped
disintegration and persisted as a micro
moon before crashing cataclysmically to
Earth.
[Music]
Ultimately, we still know too little
about it, but it's a tantalizing
possibility. Should we discover
meteorite fragments of the right
chemical composition embedded in damaged
rocks of the right time period, then we
would have our smoking gun to link the
El Condrite planet to the udivision
ringbearing era of boom and bust.
And so while a rocky ring system around
the earth would have been a remarkable
sight both from the earth and from
space, those rings had the potential to
deal fortune and fatality to life on our
planet. They may have decided what
animal groups lived and died and thereby
shaped the future of all animal
evolution.
[Music]
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