The skull of Australopithecus Sediba

The skull of Australopithecus Sediba at the UK's Natural history Museum, London.

It is currently the hottest topic in palaeoanthropology, and visitors to London's Natural History Museum can now get to see what all the fuss is about. 

This 1.9-million-year-old creature caused a sensation when the discovery of its fossil remains in South Africa was first announced in 2010.

A. sediba has a curious mix of ape and human features, suggesting it could be one of our direct ancestors.

"This is one of the most exciting and controversial fossil finds of recent years and it's fantastic to have this material at the museum," said Prof Ian Owens, the NHM's director of science.

"Researchers will get to work with it, but also the public will get to see it, and we hope that will really help bring the science alive," he told BBC News.

The replicas are a gift from the government of the Republic of South Africa and the University of the Witwatersrand, which is leading the investigation into the fossils.

The real specimens were found at Malapa in the famous Cradle of Humankind World Heritage Site, just to the northwest of Johannesburg.

They were pulled from a pit - a depression left in the ground by a cave complex that subsequently lost its roof through erosion.

Identified as the remains of an adult female and a juvenile male, the two individuals were quite possibly mother and son.

It seems they died together in some tragic accident that saw them either fall into the cave complex or become stuck in it.

After death, their bodies were washed into a pool and cemented in time along with the skeletons of many other animals - sabre-tooth cats, hyenas, antelope, even birds and mice.

"All of this accumulation happened very, very quickly - in a few days, weeks or months," said lead researcher Prof Lee Berger of the Institute for Human Evolution at Wits University.

"Once we've completed this project, we're going to be able to show a texture of a moment in time that we have never seen before except in maybe the eruption of Mount Vesuvius and the burial of Pompeii."

Scientists are now engaged in an intense debate over the status of A. sediba in the story of our origins.

Prof Berger and his colleagues say the creature's mix of ancient and modern traits probably make it central to that story. They propose that A. sediba could even sit on, or very close to, the line that led directly to us - modern humans (Homo sapiens).

Other scientists remain to be convinced, and argue too little is known about the diversity of ancient human forms this far back in time to make any bold statements.

The United Nations of science: We really need it

The United Nations of science: why we really need it - New Scientist

AS THE disappointment of the Copenhagen climate summit sinks in, you could be forgiven for despairing of science ever being put at the centre of international policy-making. But scientists are not giving up the fight.

This week, an important meeting is taking place at the Royal Society in London. The outcome will determine how the world's finest scientific minds engage collectively with governments worldwide to make sure they have the benefit of the best possible scientific advice.

The meeting is of a body you may never have heard of: the InterAcademy Panel on International Issues (IAP), a global coalition of national science academies from Albania to Zimbabwe. Its task this week is to agree a way forward for scientific advice to government - how the world of science, speaking as one, can reach out to policy-makers to help solve the critical global challenges we now face.

The IAP was founded in New Delhi, India, in 1993 in response to growing concerns about world population. It has since grown in size and reputation as more and more academies have joined its ranks and new ones have been founded. From the Royal Society, the oldest academy in continuous existence, to the academies of Mozambique and Nicaragua, both founded a year ago, the IAP now has 103 members. The most recent member is the Academy of Sciences of Afghanistan. It is the United Nations of science.

IAP has worked on issues as diverse as population growth, ocean acidification and the teaching of evolution. The organisation's ambition is to become the most influential voice for the world's scientists amid the clamour of politicians and lobby groups.