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of the fossil slabs have a rough, stippled texture like elephant skin, the remnant of the slimy bacterial
mats that were draped over the Ediacaran seafloor. A few years ago Jim realized that these mats also
helped preserve a record of the Ediacaran fossils.
The idea came from an old image. As a child, Jim was flicking through an encyclopedia when he
saw a picture of the death mask taken from the corpse of the notorious outlaw of the Australian Out-
back, Ned Kelly. Jim can still remember the imprint that Kelly's eyelashes had left behind, and the
shape of his chin. And when Jim was studying the fossil slabs, he realized that the slimy mats would
have provided each Ediacaran with a death mask just like Kelly's.
As soon as the Ediacarans died, bacteria would have rushed to cover them, greedily absorbing
their nutrients, and extruding chemicals that bound the sand above into a tough, yellow mineral of
iron called pyrite. Even when the soft body rotted away, this pyrite shell would have stood firm. Now,
hundreds of millions of years later, that same iron crust survives on the underside of each sandstone
slab; it has rusted now to red iron oxide, but still provides a faithful mold of the creature that once lay
beneath. 5
This means of preservation captured not just individuals, but a slice of life, a snapshot of the Edi-
acaran seafloor. Unfortunately the sand also squashed many of its victims before their death masks
formed. This has left Jim and his colleagues with a quandary. Some Ediacarans were born flat, some
became flat; how do you tell the difference? Interpreting the impressions of these crushed bodies is
certainly an art—hence the business earlier with the coke can. (“Arm-wrestle for it!” one exasperated
onlooker told the researchers who had spent most of a field trip wrangling pointlessly about the ap-
pearance—when alive—of a particularly smudgy fossil.) But there are clues in the rocks, if you know
how to read them. Are the fossils ever folded over? Then they must have been flat when they were
alive. Are they all lying in the same orientation? Then perhaps they were bound into the seafloor, and
all swaying in the same current, when the deadly sandstorm hit.
From this kind of analysis, some things have become clear. The Ediacarans were definitely
alive—no geological process can make shapes like theirs. They were also much larger than the micro-
scopic creatures of Slimeworld. And though some look like nothing on Earth, others are uncannily like
more modern animals—starfish, jellyfish, sponges and sea pens. These resemblances have led many
researchers—Jim among them—to believe that at least some of the Ediacarans were direct ancestors of
the complex animals we see today. But everyone admits that shapematching isn't enough. Though the
fossils look complicated, they could still be some strange aggregation of simpler creatures. Over the
years people have speculated that each Ediacaran could have been one giant single cell, quilted into
many fluid-filled compartments, like an air mattress; or perhaps even some exceptionally coordinated
colonies of bacteria, banding together into deceptively complex shapes. 6
As it turns out, they are neither of these. We now know that Ediacarans truly were the first com-
plex, multicellular animals. The proof has emerged only in the past couple of years, and it comes not
from the shape of the fossils, but from their trails .
I N HIS collection at the Institute of Palaeontology in Moscow, Misha Fedonkin has some of the best
Ediacaran fossils in the world. Misha is a dapper man in his early fifties, with a short, tidy moustache
and jet-black hair. His English, like his manner, is fluent. He is charming and suave, often animated
but never, ever ruffled. After decades of doing science in Russia, he is also in-finitely resourceful. That
doesn't just apply to fieldwork. Put him in the residential part of an unfamiliar city, and he will im-
mediately find you a delightful little bar, club or restaurant, just around the corner. When Misha was
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