A team of International scientists have announced the discovery of a new species of human relative.

The new species, named Homo naledi, has surprisingly human-like features and was discovered in a remote cave 30 miles north-west of Johannesburg, South Africa.

With a brain the size of an orange, a slender body, ape-like shoulders and feet almost identical to humans, the find provides a unique insight into our human past.

 Standing at approximately 5ft tall and weighing almost 100lbs, scientists claim the ancestor's skull shows a marked similarity to our own.

The 1,550 fossil elements excavated from the cave are believed to be parts of at least 15 infants, children, adults and elderly of the same species - and are just a small fraction of the fossils discovered.

Announced by the University of the Witwatersrand, the National Geographic Society and the South African Department of Science and Technology, the discovery sheds light on the origins and diversity of human ancestry.

 Lee Berger, research professor in the Evolutionary Studies Institute at the University of the Witwatersrand, led the two expeditions that discovered and recovered the fossils.

Professor Berger said: "With almost every bone in the body represented multiple times, Homo naledi is already practically the best-known fossil member of our lineage."

 The fossils lay in a chamber about 90 metres from the cave entrance, accessible only through a chute just 18-centimetres wide.

In the first expedition, over a period of 21 days, more than 60 cavers and scientists worked together to remove the fossils from the chamber.

The task required a special team of slender cavers dubbed 'underground astronauts' to remove the material.

Marina Elliott, one of the excavating scientists, described the process as "some of the most difficult and dangerous conditions ever encountered in the search for human origins".

John Hawks of the University of Wisconsin-Madison, said: "Overall, Homo naledi looks like one of the most primitive members of our genus, but it also has some surprisingly human-like features, enough to warrant placing it in the genus Homo.

"H. naledi had a tiny brain, about the size of an average orange, perched atop a very slender body."

 H. naledi's teeth are described as similar to those of the earliest-known human relatives, as are most features of the skull but the shoulders are more similar to those of apes.

Dr Tracy Kivell of the University of Kent, in the UK, said: "The hands suggest tool-using capabilities.

"Surprisingly, H. naledi has extremely curved fingers, more curved than almost any other species of early hominin, which clearly demonstrates climbing capabilities."

Dr William Harcourt-Smith of Lehman College, City University of New York, and the American Museum of Natural History, who led the study of H. naledi's feet described them as "virtually indistinguishable from those of modern humans."

 "The feet, combined with its long legs, suggest that the species was well-suited for long-distance walking," he said.

Professor Berger added: "The combination of anatomical features in H. naledi distinguishes it from any previously known species."

The researchers believe the most remarkable aspect of the find is that the primitive-looking discovery may have practiced a form of behaviour thought to be unique to humans - depositing bodies of its dead in a remote cave chamber.

Dr Paul Dirks, of James Cook University in Queensland, Australia, said: "That room has always been isolated from other chambers and never been open directly to the surface.

 "What's important for people to understand is that the remains were found practically alone in this remote chamber in the absence of any other major fossil animals."

Despite the dramatic revelation researchers claim a lot remains to be discovered from the cave.

Professor Berger said: "This chamber has not given up all of its secrets.

"There are potentially hundreds if not thousands of remains of H. naledi still down there."