They were going to build a rubbish dump on the site until palaeontologists found 83 fragments of bone which have turned out to be a key discovery for the theory of evolution. The missing link between man and large apes has been found in Barcelona; it is a new species, lived 13 million years ago, and has been christened "Pau." Scientists believe Pau to be an example of a species which opens the window on the period between four-legged monkeys and human bi-peds.

The discovery was made last year in Anoia (Barcelona), and following a year of investigations, scientists Salvador Moyá and Meike Koler, have just published their conclusions. Pau was less than a metre tall and weighed less than 35kg. With his hands stretched above his head, he could stand on his hind legs and swing from the lower branches of trees quite easily as the bones of his hand and arm were joined by a sole articulation, which allowed him to perform previously impossible movements. 

They have assigned it to an entirely new family and species: Pierolapithecus catalaunicus. Great apes are thought, on the basis of genetic and other evidence, to have separated from another primate group known as the lesser apes some time between 11 and 16 million years ago.

It is fascinating, therefore, for a specimen like Pierolapithecus to turn up right in this window. Scientists think the creature lived after the lesser apes went their own evolutionary way, but before the great apes began their own diversification into different forms such as orang-utans, gorillas, chimps and, of course, humans. "Pierolapithecus probably is, or is very close to, the last common ancestor of great apes and humans," said Professor Moyà. The new ape's ribcage, lower spine and wrist display signs of specialised climbing abilities that link it with modern great apes, say the researchers.