Strange fossil defies grouping

[Blackleaf]

A strange 525 million-year-old fossil creature is baffling scientists because it does not fit neatly into any existing animal groups.

The animal, from the early Cambrian Period, might have belonged to a now extinct mollusc-like phylum, academics from America and China say.

Other researchers have suggested the creature could represent an early annelid or arthropod.

Details are published in Proceedings of the Royal Society B.

The 5-10cm-long (2-4 inch) fossil, from Anning in China, had a flattened body and horizontal fins which, researchers think, could have been used to support it as it moved along the sea floor. It also had well developed senses, including a pair of eyes on stalks.

The trouble is the animal, named Vetustodermis planus, did not possess a set of features, or characters, which placed it clearly within any known group.

When it was first described in 1979, Vetustodermis was included in the annelid category. Later researchers argued against this classification, saying it was, in fact, either an arthropod or a mollusc.

Flat foot

According to the latest study, the weird creature seems closest to molluscs, primarily because it had a snail or slug-like flat foot. However, the researchers say, it does not sit happily in this group.

"Phyla are defined by an organism having a set of features called characters, and currently there are no animals that we know of which contain the set of characters that Vetustodermis has," co-author David Bottjer, of the University of Southern California, US, told the BBC News website.

Vetustodermis planus does not fit comfortably within any known phylum

"The phylum with which it shares the most characters is the Mollusca, but squeezing Vetustodermis into the mollusca is a somewhat messy job."

Since Vetustodermis requires some "pushing and pulling" to force it into any known phylum, Professor Bottjer and his colleagues are tempted to speculate it belonged to a different group entirely; one which flourished and faded within the Cambrian.

"We have always been intrigued by the many molluscan features of these fossils, but in the great menagerie of organisms that have inhabited Earth through life's long history, we may come to conclude that Vetustodermis indeed represents a new phylum," he said.

Jonathan Todd, a palaeontologist from the Natural History Museum, London, UK, is also mystified by the baffling animal.

"It is an intriguing beast," he told the BBC News website. "It is another strange thing from the Cambrian. It doesn't look much like an arthropod and I don't find its molluscan affinities particularly convincing."

Evolutionary tree

However, Dr Todd is reluctant to create a whole new phylum to accommodate Vetustodermis; that, he thinks, would be premature.

"Some scientists have thought that there were so many distinct phyla in the Cambrian," he said. "They came to that conclusion because they were not thinking in the phylogenetic sense, they were thinking 'hey, that is a unique set of features - it must be a distinct phylum'."

So rather than creating new phyla every time something doesn't fit an existing one, the really interesting exercise, Dr Todd thinks, is to establish just how Vetustodermis slotted into the greater evolutionary tree.

If, indeed, it did belong to a different phylum, how did that group connect to the molluscs, annelids and arthropods?

"We don't really know the phylo-genetic relationships between the extant phyla," he said. "Molecular genetics has only gone so far. But recent phyla have got to connect somehow. These fossils really offer the opportunity to tie together recent phyla."

news.bbc.co.uk

[Cody lee Williams]

It looks like a mix between a cockroach and a squid

[isis-999]

It looks more like a slug to me..A very ugly slug..

[marduk]

an exctinct unclassfiable rock

[isis-999]

Naaa.. a ugly slug, with metal on it if you ask me..

[DJ_Quinn]

It looks cool. I want one.

[isis-999]

Then we shall have too find you one. If someone can tell us what it really is.

[Mr Supertypo]

it reminds me the HALLUCIGENIA another unclassificable fossiles. With seven tentacles on it back and with sharp swordlike legs.

Scientisist have been for years unable to find out what it was uintil they found out htey were holding the fossile upside down

just search on google the word hallucigenia and have a laugh

[isis-999]

OMG LUX>>> That was so funny, it just goes to show even great mind's get it wrong, if they look at it from one side only.

[theSOURCE]

It's a fossil of Trunko!

[Yelekiah]

Which Einstein thought it was an early annelid???

[LarryOldtimer]

It looks more like a slug to me..A very ugly slug..

Is there any other kind?

[LarryOldtimer]

Sort of reminds me of:

Six Wise Men of Hindustan

There were six men of Hindustan,

to learning much inclined,

Who went to see an elephant,

though all of them were blind,

That each by observation

might satisfy his mind.

The first approached the elephant,

and happening to fall

Against his broad and sturdy side,

at once began to bawl,

"This mystery of an elephant

is very like a wall."

The second, feeling of the tusk,

cried, "Ho, what have we here,

So very round and smooth and sharp?

To me 'tis mighty clear,

This wonder of an elephant

is very like a spear."

The third approached the elephant,

and happening to take

The squirming trunk within his hands,

thus boldly up and spake,

"I see," quoth he,

"the elephant is very like a snake."

The fourth reached out an eager hand,

and felt above the knee,

"What this most wondrous beast

is like is very plain" said he,

"'Tis clear enough the elephant

is very like a tree."

The fifth who chanced to touch the ear

said, "E'en the blindest man

Can tell what this resembles most;

deny the fact who can;

This marvel of an elephant

is very like a fan."

The sixth no sooner had begun

about the beast to grope,

Than seizing on the swinging tail

that fell within his scope;

"I see," said he, "the elephant

is very like a rope."

So six blind men of Hindustan

disputed loud and long,

Each in his own opinion

exceeding stiff and strong;

Though each was partly in the right,

they all were in the wrong!

[muddyfrog]

Thats awesome larry...

Who wrote it?

[JoeBean24]

Hmm well even if it doesnt fit into any known group im sure certain groups have long since vanished from this planet.