The Lazarus Effect: rodent 'missing' for 11 million years is discovered in Laos

A bizarre rodent that was discovered last year in a remote region of south-east Asia has turned out to belong to a family of mammals that was thought to have gone extinct more than 11 million years ago, a study has found.

A new analysis of the rodent's remains indicates that it is a striking example of the "Lazarus effect", when members of a species thought to be extinct are found living in an isolated part of the world.

The animal, called Laonastes aenigmamus, was identified last year by scientists who recognised it as a new species from dead specimens trapped in the wild and sold as food in the markets of Laos.

Laonastes was so unusual - not quite a rat or squirrel but not a guinea pig - that it was classified as the only living member of an entirely new mammal family, a rare honour in zoology.

However, Mary Dawson and Chris Beard at the Carnegie Museum of Natural History have looked deep into the mouth of Laonastes and found that its teeth are remarkably similar to those belonging to a family of Asian mammals called Diatomyidae which went extinct 11 million years ago.

"We knew exactly what we were looking at. The teeth were the most telling sign. We were sure we were looking at living Diatomyidae," Dr Beard said.

It is unusual for scientists to identify a living member of an extinct group of animals. The most famous example of the Lazarus effect was the capture of a live prehistoric fish called a coelacanth by fishermen off the east coast of South Africa in 1938.

Dr Dawson said that placing Laonastes in the Diatomyidae family of rodents is just as unusual given that the Lazarus effect in mammals only usually extends back no more than a few thousand years.

"It is an amazing discovery and it's the coelacanth of rodents. It's the first time in the study of mammals that scientists have found a living fossil of a group that's thought to be extinct for roughly 11 million years," Dr Dawson said. "That's quite a gap. Previous mammals had a gap of only a few thousand to just over a million years," she said.

The study, published in the journal Science, found that Laonastes and Diatomyidae share dental features such as molars with four roots and incisors with unusual microscopic structures etched into the enamel.

Paula Jenkins, the mammal specialist at the Natural History Museum in London, who initially described Laonastes, said the new research is fascinating, important and supported by convincing evidence.

"The idea of Laonastes as an example of the Lazarus effect is incredibly exciting and inspiring. It is very rare for a species believed to be extinct to show the Lazarus effect," Dr Jenkins said.

The identification of Laonastes was done with the help of the remains of 15 specimens which had all been collected by local hunters. There were also five skull fragments retrieved from regurgitated owl pellets.

"I would expect these specimens of Laonastes to be studied again and again and for their evolutionary relationships to be subjected to intense scrutiny," she said. "It would be surprising if the theory advanced in this paper were to remain unchallenged in future years, but that is what is so exciting about science."

Laonastes, known locally as Kha-Nyou, has never been observed in the wild and is believed to be a shy, nocturnal creature whose way of life is under threat. "It's the sole survivor of a very distinctive family of rodents with deep evolutionary roots in Asia. Every effort should be made to protect and preserve the living Laonastes," Dr Beard said.

Back from the dead

COELACANTH - Thought to have become extinct 80 million years ago. Found again in 1938

MADEIRAN LAND SNAIL (Discus guerinianus) - Extinct in 1996. Found again in 1999

FERNANDINA RICE RAT (Nesoryzomys fernandinae) - Extinct in 1996. Found again in late 1990s

IVORY-BILLED WOODPECKER (Campephilus principalis) - Extinct in 1944. Sighted in 1999, found again in 2005.

MOUNT DIABLO BUCKWHEAT (Eriogonom truncatum) - Extinct around 1935. Found again in 2005

JERDON'S COURSER WADER (Rhinoptilus bitorquatus) from India, assumed extinct until 1986.

LORD HOWE ISLAND STICK INSECT (Dryococelus australis) - Thought extinct from about 1918, rediscovered in 2001.

BAVARIAN PINE VOLE (Microtus bavaricus) - Rediscoverd in Austria in 2001.

Start your day with The Independent, sign up for daily news emails
Voices
There will be a chance to bid for a rare example of the SAS Diary, collated by a former member of the regiment in the aftermath of World War II but only published – in a limited run of just 5,000 – in 2011
charity appealTime is running out to secure your favourite lot as our auction closes at 2pm today
News
people
News
Elton John and David Furnish exchange marriage vows
peopleSinger posts pictures of nuptials throughout the day
News
File: James Woods attends the 52nd New York Film Festival at Walter Reade Theater on September 27, 2014
peopleActor was tweeting in wake of NYPD police shooting
PROMOTED VIDEO
Sport
Martin Skrtel heads in the dramatic equaliser
SPORTLiverpool vs Arsenal match report: Bandaged Martin Skrtel heads home in the 97th-minute
Arts and Entertainment
The Lord of the Rings and The Hobbit director Peter Jackson with his star on the Hollywood Walk of Fame
film
News
people
News
Billie Whitelaw was best known for her close collaboration with playwright Samuel Beckett, here performing in a Beckett Trilogy at The Riverside Studios, Hammersmith
people'Omen' star was best known for stage work with Samuel Beckett
Arts and Entertainment
Mark Wright has won The Apprentice 2014
tvThe Apprentice 2014 final
News
i100
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Manufacturing Manager

£35000 - £38000 per annum: Recruitment Genius: This is a rare opportunity for ...

Recruitment Genius: Conveyancing Fee Earner / Technical Support

£20000 - £30000 per annum: Recruitment Genius: An experienced Fee Earner/Techn...

Recruitment Genius: Receptionist

Negotiable: Recruitment Genius: This law firm is seeking a happy, helpful and ...

The Jenrick Group: Production Supervisor

£26000 - £29000 per annum + Holidays & Pension: The Jenrick Group: Production ...

Day In a Page

Surrounded by high-rise flats is a little house filled with Lebanon’s history - clocks, rifles, frogmen’s uniforms and colonial helmets

Clocks, rifles, swords, frogmen’s uniforms

Surrounded by high-rise flats is a little house filled with Lebanon’s history
Return to Gaza: Four months on, the wounds left by Israel's bombardment have not yet healed

Four months after the bombardment, Gaza’s wounds are yet to heal

Kim Sengupta is reunited with a man whose plight mirrors the suffering of the Palestinian people
Gastric surgery: Is it really the answer to the UK's obesity epidemic?

Is gastric surgery really the answer to the UK's obesity epidemic?

Critics argue that it’s crazy to operate on healthy people just to stop them eating
Homeless Veterans appeal: Christmas charity auction Part 2 - now LIVE

Homeless Veterans appeal: Christmas charity auction

Bid on original art, or trips of a lifetime to Africa or the 'Corrie' set, and help Homeless Veterans
Pantomime rings the changes to welcome autistic theatre-goers

Autism-friendly theatre

Pantomime leads the pack in quest to welcome all
The week Hollywood got scared and had to grow up a bit

The week Hollywood got scared and had to grow up a bit

Sony suffered a chorus of disapproval after it withdrew 'The Interview', but it's not too late for it to take a stand, says Joan Smith
From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?

Panto dames: before and after

From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?
Thirties murder mystery novel is surprise runaway Christmas hit

Thirties murder mystery novel is surprise runaway Christmas hit

Booksellers say readers are turning away from dark modern thrillers and back to the golden age of crime writing
Anne-Marie Huby: 'Charities deserve the best,' says founder of JustGiving

Anne-Marie Huby: 'Charities deserve the best'

Ten million of us have used the JustGiving website to donate to good causes. Its co-founder says that being dynamic is as important as being kind
The botanist who hunts for giant trees at Kew Gardens

The man who hunts giants

A Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there
The 12 ways of Christmas: Spare a thought for those who will be working to keep others safe during the festive season

The 12 ways of Christmas

We speak to a dozen people who will be working to keep others safe, happy and healthy over the holidays
Birdwatching men have a lot in common with their feathered friends, new study shows

The male exhibits strange behaviour

A new study shows that birdwatching men have a lot in common with their feathered friends...
Diaries of Evelyn Waugh, Virginia Woolf and Noël Coward reveal how they coped with the December blues

Famous diaries: Christmas week in history

Noël Coward parties into the night, Alan Clark bemoans the cost of servants, Evelyn Waugh ponders his drinking…
From noble to narky, the fall of the open letter

From noble to narky, the fall of the open letter

The great tradition of St Paul and Zola reached its nadir with a hungry worker's rant to Russell Brand, says DJ Taylor
A Christmas ghost story by Alison Moore: A prodigal daughter has a breakthrough

A Christmas ghost story by Alison Moore

The story was published earlier this month in 'Poor Souls' Light: Seven Curious Tales'