In the summer of 1956, a teenage girl named Tina  Negus stumbled upon an utterly impossible fossil.

She was visiting Charnwood Forest - a hilly  and rugged landscape in Leicestershire,   England, with some of the oldest  exposed rocks in the country.

They date back to the Precambrian, with  some more than 600 million years old.

And, while exploring an old quarry in the  forest, Tina found herself at the right   place at the right time to spot something  in the wrong place at the wrong time.

A fossil - and a pretty beautiful one at that  - kind of shaped like the frond of a fern.

But there was just one problem.

It was almost   a geological law that rocks this  old could never contain fossils.

Because it was common knowledge that  multicellular organisms with complex body   plans only emerged later, in the Cambrian  explosion around 541 million years ago.

Yet here was a fossil that would  eventually make us reconsider   much of what we thought we knew  about the earliest complex life.

And it wouldn’t be the last  big find in the forest.

More than 60 years later, another  discovery would shine a light on an   adaptation that today we take for granted -  but it might have been a first for its time.

Hidden in the rocks once thought  too old to contain complex life,   we may have found the animal  kingdom’s oldest known predator.

Sadly, Tina would never get credit for spotting  that frond-shaped fossil.

Her report was dismissed   by her geography teacher’s emphatic claim that  “there are no fossils in Precambrian rocks!” The credit would go instead to another local kid   named Roger Mason who came across  the same fossil the following year.

He made a rubbing of the imprint and finally  convinced a local geology professor that it   really was a Precambrian fossil - the  first one ever recognized as such.

It was named Charnia masoni, after  both Charnwood Forest and Roger Mason,   who would grow up to become  a geology professor himself.

It dates to around 570 million years ago,   and it sparked a revolution of our  understanding of Precambrian life.

Before the discovery of Charnia, scientists  thought that life in this period was basically   all microbial - too small, simple, and squishy  to leave behind any real fossil evidence.

Even Sir David Attenborough, who grew  up nearby, had avoided looking in these   particular rocks while fossil hunting in his  youth.

He assumed that they were just too old.

But almost as soon as Charnia was officially  described, researchers began to realize that other   finds from around the world were also fossilized  macro-scale organisms from the Precambrian.

In some cases, these finds had previously  been dismissed as patterns created by   ancient geological forces, rather  than being biological in origin.

Others had been recognized as fossils,  but the rocks they were in hadn't been   reliably dated.

So, they were assumed  to be from the Cambrian because…well,   all fossils could only be as  old as the Cambrian, right?

But the news of Charnia triggered a  radical reassessment of many of our   old assumptions.

Suddenly, the concept of  a Precambrian world of complex lifeforms   went from being impossible to  being impossible to ignore.

And in the years since then, many  more of these weirdos have been   described from around the world -  from Canada to Namibia to Australia.

This collection of ancient creatures became  known as the ‘Ediacaran Biota,’ named for   the geological period they inhabited  – the one right before the Cambrian.

They’ve revealed to us a previously  unknown chapter in the history of   life.

One in which groups of complex, macroscopic,   and bizarre organisms diversified and  thrived well before the Cambrian explosion.

And Charnwood Forest has continued to  be an exceptionally valuable window   into the life forms of this period.

Many of the oldest and best-preserved   fossils from the Ediacaran have been found there.

Some of the most abundant belong to a group  called the Rangeomorphs, which includes Charnia.

Like most Ediacaran life,   these soft-bodied organisms were  totally unlike anything alive today.

They were bound to the sea floor via  a holdfast and didn’t move around.

And they had a fern-like frond structure  that branched off their central stem that   gave them a plant like-appearance.

But they weren't plants at all.

They lived too deep for much light to  reach them, so they didn’t photosynthesize.

But they also lacked a clear mouth, gut,  or any other kind of feeding apparatus.

In fact, they don't seem to have  actively done anything to feed.

Predation hadn't been invented yet,   beyond a few Ediacaran groups that may  have grazed on microbial mats and algae.

Actively catching and eating other  organisms only became common with   the rise of modern animal groups in the Cambrian.

Instead, our best guess at the moment is that   they passively absorbed dissolved  organic carbon from the seawater.

But while rangeomorphs like Charnia are  some of the earliest and most abundant   Ediacaran lifeforms, a diverse range of other  weirdos also appeared alongside them later on.

Some lived at other depths, some were mobile,   and they came in a range of shapes and sizes,  including tubes, discs, bags, and quilts.

They’re generally so strange  and alien-looking that it’s   been a real struggle to figure out  both how they relate to each other   and how they relate to later animal groups  that became dominant in the Cambrian.

Some have been tentatively  interpreted as primitive   members of those animal groups -  though not without controversy.

But most seem like entirely separate evolutionary   experiments with no direct link  to any animals living today.

But in that crowd of ancient strangers,  we have seen one familiar face.

In 2022, scientists reported a new out-of-place   fossil from Charnwood Forest that  once again broke all the rules.

It was found preserved  alongside some rangeomorphs,   close to the site where Tina  had found the first Charnia.

And it dated to around 560 million years ago,   nearly 20 million years  before the Cambrian explosion.

While the vast majority of Ediacaran fossils  from this period seemed completely alien,   this one seemed instantly familiar  to some animals living today.

Like the rangeomorphs, it probably anchored  itself to the sea floor.

But unlike those   soft-bodied strangers, it had a skeleton -  the oldest one ever seen in the fossil record.

And it forked into two goblet-shaped  structures that contained dense clusters   of tentacles, a lot like some living animals.

The researchers realized that  this was the earliest Precambrian   fossil to clearly show the body  plan of a modern animal group.

And, potentially, the oldest animal with  direct living descendants in the fossil record.

The researchers concluded that it  was the earliest known cnidarian,   a phylum of animals that includes  anemones, corals, and jellyfish.

Now, cnidarians have long been considered  one of the most ancient animal lineages,   and previous molecular analyses had  hinted that they had already evolved   and begun to diverge prior  to the Cambrian explosion.

But this had never been confirmed,  because unambiguous fossils of   Precambrian cnidarians - or any other modern  animal group - had been missing, until now.

Within that phylum, this new find seemed  to be a member of the subgroup Medusozoa,   making it an ancient jellyfish relative.

It closely resembled a life-cycle  stage common to many medusozoans,   during which they form an immobile stalked  polyp before eventually becoming free-swimming.

Though, whether this ancient critter  also had a free swimming stage,   or if that evolved later, we don’t know yet.

And rather than passively absorbing nutrients  from the water, it likely used its tentacles   for the same thing modern medusozoans use them for  - capturing prey, probably plankton and protists.

This makes it potentially the  oldest animal predator ever found,   pushing back the evolution of  predation by around 20 million years!

The researchers named it  Auroralumina attenboroughii,   meaning Attenborough’s Dawn Lantern,  after the local legend himself.

‘Dawn’ referenced its immense age - the fossil’s,   not Attenborough’s - and ‘lantern’ honored the  cupped tentacles’ resemblance to a flaming torch.

While the discovery of Charnia unexpectedly showed  that large complex life pre-dated the Cambrian,   the discovery of Auroralumina went a step further.

It showed that at least one recognizable animal  group - cnidaria - was also around during   this period, living and diversifying  alongside other Ediacaran weirdos.

And, even this early on, they had already  established a modern cnidarian body plan and   a predatory lifestyle - two innovations that were  previously only known from the Cambrian onwards.

It was an out-of-place fossil in a wider group of  out-of-place fossils.

While those other Ediacaran   species had surprised us by being so weird,  this one surprised us by being so familiar.

More than 60 years after Tina’s discovery,   Charnwood Forest continues to blow our  minds, shift our paradigms, and show us