The tree-climbing girl who turns the history of man on its head

 

The fragile remains of a three-year-old girl who died about 3.3 million years ago in East Africa have revealed that our early human ancestors still spent much of their time in the trees long after they had fully mastered the art of walking on two legs.

The discovery appears to have finally ended the debate over whether this bipedal hominid still continued to climb trees, much like their earlier ape ancestors.

The fossilised shoulder blades and arm sockets belonging to Selam, meaning "peace", indicate that she and her family continued to climb trees like modern apes even though her lower body was perfectly adapted to upright walking.

Scientists believe that the upward angle of her arm sockets and ape-like shoulder blades suggest that she was an active tree climber. This means that humanity's earliest ancestors abandoned an arboreal existence far later in our evolutionary history than previously thought.

Selam is a remarkably well-preserved specimen of the species Australopithecus afarensis, an important forerunner of the human lineage. Her almost-complete skull and skeleton, embedded in sandstone rock, was discovered in 2000 in the Dikika region of northeast Ethiopia and it has taken years of painstaking work for scientists to extract the fossilised bones from the stone.

The latest study, published in the journal Science, reveals the first complete set of shoulder blades of Australopithecus afarensis.

"The question as to whether Australopithecus afarensis was strictly bipedal or if they also climbed trees has been intensely debated for more than 30 years," said Professor David Green, curator in anthropology at the California Academy of Sciences and one of the authors of the study.

"These remarkable fossils provide strong evidence that these individuals were still climbing at this stage in human evolution," Professor Green said.

Trees were probably still an important refuge from the many large predators that roamed the land at the time. Trees were especially important for females nursing infants, especially at night.

Humans and apes shared their last common ancestor about 6.5 million years ago. The discovery in the same region of Ethiopia in 1974 of the first Australopithecus skeleton, a female called Lucy, showed that upright walking on two legs had evolved more than 3 million years ago, long before the emergence of the human genus "Homo" about a million years later.

Zeresenay Alemseged of the California Academy of Scientists, the scientist who first discovered Selam, has spent the past 11 years trying to extricate the bones, especially her fragile shoulder blades, from their sandstone tomb.

"Because shoulder blades are paper thin they rarely fossilise, and when they do they are almost always fragmentary. So finding both shoulder blades completely intact and attached to a skeleton of a known and pivotal species was like hitting the jackpot," Dr Alemseged said.

"This study moves us a step closer toward answering the question 'when did our ancestors abandon climbing behaviour?' It appears that this happened much later than many researchers have previously suggested," he said.

Descending from the trees and learning to walk upright on two legs is considered one of the defining moments in human evolutionary history that set our distant ancestors on the path towards sophisticated took making, the control of fire and complex social behaviour.

"This new find confirms the pivotal place that Lucy and Selam's species occupies in human evolution. While [they were] bipedal like humans, A. afarensis was still a capable climber. Though not fully human. A. afarensis was clearly on its way," Dr Alemseged said.

Although chimps and modern humans shared their last common ancestor about 6.5m years ago, it was only just over 2m years ago that the first humans emerged in the form of Homo habilis, or "handy man",  a tool-making species with half the brain size of modern man.

News
peopleFrankie Boyle responds to referendum result in characteristically offensive style
News
news
Life and Style
Couples have been having sex less in 2014, according to a new survey
life
New Articles
i100... with this review
PROMOTED VIDEO
Voices
Holly's review of Peterborough's Pizza Express quickly went viral on social media
Sport
footballTim Sherwood: This might be th match to wake up Manchester City
Arts and Entertainment
musicHow female vocalists are now writing their own hits
New Articles
i100
News
ebooksAn unforgettable anthology of contemporary reportage
News
news
Arts and Entertainment
musicBiographer Hunter Davies has collected nearly a hundred original manuscripts
News
Blahnik says: 'I think I understand the English more than they do themselves'
people
Arts and Entertainment
Michelle Dockery as Lady Mary Crawley in Downton Abbey
TVInside Downton Abbey series 5
Life and Style
The term 'normcore' was given the oxygen of publicity by New York magazine during the autumn/winter shows in Paris in February
fashionWhen is a trend a non-trend? When it's Normcore, since you ask
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

Marketing Manager - Leicestershire - £35,000

£30000 - £35000 per annum: Ashdown Group: Marketing Manager (CIM, B2B, MS Offi...

Marketing Executive (B2B and B2C) - Rugby, Warwickshire

£22000 - £25000 per annum: Ashdown Group: A highly successful organisation wit...

SEN Coordinator + Teacher (SENCO)

£1 per day: Randstad Education Leeds: Job Purpose To work closely with the he...

Research Manager - Quantitative/Qualitative

£32000 - £42000 Per Annum: Clearwater People Solutions Ltd: Our client is curr...

Day In a Page

Scottish referendum: The Yes vote was the love that dared speak its name, but it was not to be

Despite the result, this is the end of the status quo

Boyd Tonkin on the fall-out from the Scottish referendum
Manolo Blahnik: The high priest of heels talks flats, Englishness, and why he loves Mary Beard

Manolo Blahnik: Flats, Englishness, and Mary Beard

The shoe designer who has been dubbed 'the patron saint of the stiletto'
The Beatles biographer reveals exclusive original manuscripts of some of the best pop songs ever written

Scrambled eggs and LSD

Behind The Beatles' lyrics - thanks to Hunter Davis's original manuscript copies
'Normcore' fashion: Blending in is the new standing out in latest catwalk non-trend

'Normcore': Blending in is the new standing out

Just when fashion was in grave danger of running out of trends, it only went and invented the non-trend. Rebecca Gonsalves investigates
Dance’s new leading ladies fight back: How female vocalists are now writing their own hits

New leading ladies of dance fight back

How female vocalists are now writing their own hits
Mystery of the Ground Zero wedding photo

A shot in the dark

Mystery of the wedding photo from Ground Zero
His life, the universe and everything

His life, the universe and everything

New biography sheds light on comic genius of Douglas Adams
Save us from small screen superheroes

Save us from small screen superheroes

Shows like Agents of S.H.I.E.L.D are little more than marketing tools
Reach for the skies

Reach for the skies

From pools to football pitches, rooftop living is looking up
These are the 12 best hotel spas in the UK

12 best hotel spas in the UK

Some hotels go all out on facilities; others stand out for the sheer quality of treatments
These Iranian-controlled Shia militias used to specialise in killing American soldiers. Now they are fighting Isis, backed up by US airstrikes

Widespread fear of Isis is producing strange bedfellows

Iranian-controlled Shia militias that used to kill American soldiers are now fighting Isis, helped by US airstrikes
Topshop goes part Athena poster, part last spring Prada

Topshop goes part Athena poster, part last spring Prada

Shoppers don't come to Topshop for the unique
How to make a Lego masterpiece

How to make a Lego masterpiece

Toy breaks out of the nursery and heads for the gallery
Meet the ‘Endies’ – city dwellers who are too poor to have fun

Meet the ‘Endies’ – city dwellers who are too poor to have fun

Urbanites are cursed with an acronym pointing to Employed but No Disposable Income or Savings
Paisley’s decision to make peace with IRA enemies might remind the Arabs of Sadat

Ian Paisley’s decision to make peace with his IRA enemies

His Save Ulster from Sodomy campaign would surely have been supported by many a Sunni imam