Walking for Sex

First ape woman suggests human ancestors may have started walking in pursuit of sex

She lived at the dawn of a new era, when chimps and people began walking (or climbing) along their own evolutionary trails. This is Ardi - the oldest member of the human family tree we've found so far.

Short, hairy and with long arms, she roamed the forests of Africa 4.4million years ago.

Her discovery, reported in detail for the first time today, sheds light on a crucial period when we were just leaving the trees. Some scientists said she could provide evidence that our ancestors first started walking upright in the pursuit of sex.

Conventional wisdom says our earliest ancestors first stood up on two legs when they moved out of the forest and into the open savannas. But this does not explain why Ardi's species was bipedal (able to walk on two legs) while still living partly in the trees.

Owen Lovejoy from Kent State University said the answer could be as simple as food and sex

He pointed out that throughout evolution males have fought with other males for the right to mate with fertile females. Therefore you would expect dominant males with big fierce canines to pass their genes down the generations.

But say a lesser male, with small stubby teeth realised he could entice a fertile female into mating by bringing her some food? Males would be far more successful food-providers if they had their hands free to carry home items like fruit and roots if they walked on two legs.

Mr Lovejoy said this could explain why males from Ardi's species had small canines and stood upright - it was all in the pursuit of sex.

He added that it could also suggest that monogamous relationships may be far older than was first thought.

Ardi - short for Ardipithecus ramidus or 'root of the ground ape' - stood 4ft tall and weighed 110lb.

She lived a million years before the famous Lucy, the previous earliest skeleton of a hominid who was dug up in 1974.

Experts believe Ardi is very, very close to the 'missing link' common ancestor of humans and chimps, thought to have lived five to seven million years ago.

'This is not that common ancestor, but it's the closest we have ever been able to come,' said Dr Tim White, director of the Human Evolution Research Centre at the University of California, Berkeley, who reports the discovery today in Science. The first fossilised and crushed bones of Ardi were found in 1994 in Ethiopia's Afar Rift.

But it has taken an international team of 47 scientists 17 years to piece together, analyse and describe the remains.

Ardi's skeleton had been trampled and scattered, while the skull was crushed to just two inches in height.

Despite this, Dr David Pilbeam, curator of palaeoanthropology at Harvard's Peabody Museum of Archaeology and Ethnology said: 'This is one of the most important discoveries for the study of human evolution.

Researchers have pieced together 125 fragments of bone - including much of her skull, hands, feet, arms, legs and pelvis - which were dated using the volcanic layers of soil above and below the find.

Ardi's feet were rigid enough to allow her to walk upright some of the time, but she still had a grasping big toe for use in climbing trees.

And she had long arms but short palms and fingers which were flexible, allowing her to support her body weight on her palms.

Her upper canine teeth are more like the stubby teeth of modern people than the long, sharp ones of chimps. An analysis of her tooth enamel suggests she ate fruit, nuts and leaves.

Scientists believe she was a female because her skull is relatively small and lightly built. Her teeth were also smaller than other members of the same family that were found later.

Since the discovery, scientists have unearthed another 35 members of the Ardipithecus family.

How Ardipithecus fits into humankind's evolutionary path

He noted that Charles Darwin, whose research in the 19th century paved the way for the science of evolution, was cautious about the last common ancestor between humans and apes.

'Darwin said we have to be really careful. The only way we're really going to know what this last common ancestor looked like is to go and find it. Well, at 4.4 million years ago we found something pretty close to it,' Dr White added.

'And, just like Darwin appreciated, evolution of the ape lineages and the human lineage has been going on independently since the time those lines split, since that last common ancestor we shared.'

The search continues for the 'last common ancestor' from which both modern humans and modern chimpanzees can trace their ancestry. Many experts think the common ancestor lived at least 7 million years ago.

So Knights and Ladies...our thought for today is the four and half million years, at least, that its taken us to reach a point where we can sit and write blogs to each other. So think yourself lucky we've come this far, ( there are people in Dover, PA who won't get to learn this stuff, and if they did , they'll be told not to believe it. )

We are 99% Animal and 1% Human, and its the Human bit that causes all the trouble.

Still its nice to know that the guys back then, were bringing their Ladies Gifts. Some things should never change.

Sir Dayvd ( who now asks the KMSA members, if they were an alcoholic drink, which one would they be ? ....and Hooky before you say "A Large Stiff One"...I said it first. Me? I'd be a Glenfiddich Whiskey ..light,refined and very warming ) of O