‘Zombie’ worms found in Mediterranean fossil

Date:

Share post:

Traces of bizarre, bone-eating ‘zombie’ worms have been found on a three million year old fossil whale bone from Tuscany in Italy. 

A computer-generated reconstruction of the Osedax worm responsible for borings found in a fossil whale bone in the Mediterranean, showing its root-like tissues used for feeding [Credit: Image courtesy of University of Leeds]

It is the first time the genus Osedax has been found in the Mediterranean, and suggests Osedax were widespread throughout the world’s oceans 6 million years ago. 

The new find, published in the journal Historical Biology, confirms what scientists have long suspected – that Osedax were likely responsible for erasing parts of the fossil record by destroying bones before they could become fossils. 

Worms from the Osedax genus do not have a mouth or gut but consume the bone by growing root-like tissues, which dissolve the bone as they grow. 

Lead scientist Nicholas Higgs discovered tell-tale traces of Osedax in the Mediterranean last year using micro-CT (Computed Tomography) scanning technology as part of his PhD at the University of Leeds and the Natural History Museum. 

He says: “After several promising leads came to a dead end, the scans from the final sample looked different and I knew that I was on to something.” 

Osedax were first discovered alive in 2002 in Monterey Bay, California, where they were living on the bones of a decaying gray whale. 

Since then, scientists have been curious about how the worms might have affected fossil records, but understanding when Osedax evolved and where they lived in the past has until now remained a problem because actual remains of soft-bodied Osedax do not preserve as fossils. 

The only way to tell where and when Osedax have been at work is by distinctive bulb-shaped cavities that they leave behind in a bone – and it is these borings that have finally been recognised by Higgs. 

His research shows how widespread Osedax were millions of years ago. 

The only other known evidence of Osedax from the past is in whale bones from the Pacific coast of Washington State in the US – about as far away as it is possible to get from the Mediterranean in terms of ocean connectedness. 

When Mediterranean dried up almost six million years ago most deep sea animals were killed. About half a million years later the sea re-flooded from the Atlantic. 

Higgs says: “So finding out that Osedax were feeding on this whale bone three million years ago tell us that their ancestors must have also been living in the Atlantic as well, because the Mediterranean was re-colonised 5.5 million years ago from the Atlantic.” 

It is now almost certain that the Mediterranean is currently host to undiscovered, living Osedax species, Higgs says. 

“There are 20 different species in Monterey, California alone, so it’s almost certain there are many more out there. If Osedax were living the Mediterranean three million years ago there’s no reason why they aren’t living there now.” 

Last year, Higgs travelled to California to examine living Osedax and their borings to help understand and identify the full range of known species.  

Source: University of Leeds [November 01, 2011]

ADVERTISEMENT

spot_img

Related articles

Fossil find gives hope for animal life in ‘lost cities’

The world’s oceans could be littered with thousands of undiscovered ‘lost cities’ housing communities of creatures that thrive...

Debate on dating ‘Little Foot’ continues

Wits University Palaeontologist, Professor Francis Thackeray says he stands by the original findings regarding dating Australopithecus fossil, Little...

Supervolcanoes likely triggered externally, study finds

Supervolcanoes, massive eruptions with potential global consequences, appear not to follow the conventional volcano mechanics of internal pressure...

La Brea Tar Pit fossil research shows climate change drove evolution of Ice Age predators

Concerns about climate change and its impact on the world around us are growing daily. New scientific studies...

Archaeological works on Greek island of Thassos get coveted prize

One of the most coveted prizes in the archaeological field was awarded to the French School at Athens...

Researchers propose new way to chart the cosmos in 3D

If only calculating the distance between Earth and far-off galaxies was as easy as pulling out the old...

Women were fashion conscious 10,500 years ago

Researchers have discovered seals with geometric motifs that women stamped their bodies with and beads that they put...

High CO2 spurs wetlands to absorb more carbon

Under elevated carbon dioxide levels, wetland plants can absorb up to 32 percent more carbon than they do...