The no-prisoner Naledi wars

Mail & Guardian

09-05-2025

The discovery of a new species of human relative, Homo Naledia was unveiled at The Cradle of Human Kind at Maropeng in Johannesburg, South Africa. Naledi was discovered in a hard to reach chamber in the Rising Star Cave which has led scientists to believe that the Hominids had a understanding of the finality of death. Naledi stood about 1,5m high, had a unique mix of primitive and modern features with a tiny brain about the size of an orange, a slender body and unusually curved fingers. (Photo by Denzil Maregele/Foto24/)
It's hard to think of another scientific discovery that has caused so much ill-will.
The geo picks were out almost as soon as the Homo naledi fossils were unearthed in the Cradle of Humankind's Rising Star cave system in 2013.
Remarkably young for a creature with a brain half the size of ours, the fossils have been dated to between 335 000 and 236 000 years before present.
For University of California palaeoanthropologist Tim White the dates were irrelevant, however, as Naledi was merely a primitive, smaller version of the long-known hominin Homo erectus.
By creating a new branch of the Homo tree, Rising Star team leader Lee Berger — another American and a long-standing theoretical foe — was guilty of 'artificial species inflation'.
Leading the counter-charge was Berger's American collaborator, John Hawks, who argued that despite similarities, the two species were a poor fit.
Hawks accused senior palaeoanthropologists of 'being accustomed to secretive practices' and White, by name, for clutching details of a fossil hominin to his breast for many years.
'These [researchers] might think people would trust their authoritative pronouncements about fossil remains because no one will ever see the data.'
At stake was more than specific names. White was accusing Berger of prematurely thrusting flimsy claims into the public domain and using the media to supercharge them.
'Making sure you've got things right is … of critical importance, particularly in a science in which there are so few specimens,' he told
The Guardian
. 'Rushing things, in particular to suit film-makers, is very dangerous.'
In 2023, senior South African palaeoanthropologists Robyn Pickering and Dipuo Kgotleng doubled down on the theme. Berger, they protested, had exploited the new online publishing platform
eLife
'to launch … a carefully curated media campaign around an unreviewed narrative' that Naledi buried its dead, used stone tools and made rock art.
After a 'high-impact' journal — apparently
Nature
— stonewalled his submission, Berger switched to
eLife
. In June 2023, he posted three manuscripts as pre-prints, and before the peer reviews were out, lit up the sky with a pyrotechnic media montage including a Netflix documentary flighted in more than 20 countries.
When they landed later that year, the
eLife
peer reviews almost universally disparaged Berger's case as unproven.
This was the crisp issue — not the use of
eLife
or ready popular access to scientific data, but the launch of a media blitz based on unreviewed theories.
Pickering said she had never seen such unanimous scientific rejection of a research paper.
The outrage boiled over when two South African hominin fossils, one from Naledi, were blasted into space on a Virgin Galactic flight, carried by a white businessman who owns half the land in the Cradle.
Berger defended the move, which he cleared with the authorities, as a golden opportunity to showcase local research; critics brushed it off as a worthless gimmick that could have damaged scientific endeavour and national heritage that was not his to dispose of.
The American has an instinct for the media sweet spot. He could, for example, have picked some slightly-built male cavers to help navigate the Rising Star narrows — for stunt value, some contend, he chose only women. One source complained that there were no South Africans in his initial cohort of 'underground astronauts'.
The publicity campaign also opened up an acrimonious racial-political divide. In their blistering comment in the
South African Journal of Science
, Pickering and Kgotleng targeted a 'neo-colonial' mentality they saw as dominating local evolutionary studies, pointing out that most top scientists — who control funding and the research agenda — have been white, male and often foreign-born.
Reinforcing the bias, Pickering said in an interview, were the summer excavations by visiting American and Australian students, with a 'token' sprinkling of locals.
'There's suspicion of palaeoanthropology in our country as seeking to show black people come from monkeys. You've got to have peer reviews and local acceptance.'
American publishing behemoths like
National Geographic
(of which Berger is now 'explorer in residence' after effectively quitting academia), Netflix, Disney and CNN eagerly boarded Berger's publicity juggernaut.
This doubtless helped capitalise the Naledi exploration — but perceptions of premature media involvement and overblown headlines caused widespread disquiet.
Berger, who works through a PRO, was approached for an interview weeks ago. By the time of writing he had not replied.
Via
eLife
and the internet, he argues that the evidence of 'funerary caching', tool-making, cave scratchings and fire point to a Naledi 'culture', rather than natural vectors such as water transport and geological change.
Naledi could turn the field on its head by challenging human 'exceptionalism', making culture the 'null hypothesis' — basic causal assumption — and refocusing explorers on the cultural creativity of early Homo.
One outcome could be the re-examination of known South African sites: the Rising Star landscape, for example, was littered with stone tools traditionally traced to Middle Stone Age humans once regarded as the only hominins around. With its human-like wrists and hands, could Naledi have fashioned them?
Berger cites the old find of a hair in a hyena coprolite, interpreted as human. With hindsight broadened by the Naledi breakthrough, could it be the digested remnant of the newly discovered species?
In large part, the hypothesis rests on the charge that science has wrongly fixated on brain size as the decisive marker of human evolutionary development.
The idea that brain organisation is key, and that Naledi's diminutive brain was structured like ours, has allegedly been strengthened by endocranial studies of imprints on the skull interior.
This, he said, called for a new look at small-brained hominins unearthed and historically classed as Erectus elsewhere in Africa. Might they be Naledi, or Naledi-like?
Berger's grand idea is that a 'new Age of Discovery' is dawning in sub-equatorial Africa, where palaeo-climatic and other factors in such areas as the Kgalagadi and Lake Malawi basin favoured hominin evolution.
Given that the first Age of Discovery entailed Europe's colonial subjugation of the world, this is perhaps an unfortunate metaphor.
But the conception is a refreshing shift from the self-aggrandising pronouncements of American scientists such as Don Johanson — who discovered the fossil hominin 'Lucy' — that South Africa is an evolutionary dead end, with the real action in his and White's stamping ground of north-east Africa.
The trouble is, as one source put it, that extraordinary claims require extraordinary evidence. Berger's case is undermined by inexplicable holes in the basic research, highlighted by specialists such as Maria Martinon, director of a major Spanish research centre.
He has suggested that charcoal found in Rising Star points to controlled fire-use.
Radiocarbon dating works for organic materials up to 60 000 years old — has it been dated for recency? Sceptics insist wildfires were common in caves.
Then there is the 'tool' supposedly found close to a skeletal Naledi hand. Martinon asks why it has not been extracted from its matrix and inspected for wear, flaking and 'bulbs of percussion' to test the idea of manufacture.
How can Berger be sure that its solitary presence in the cave was not caused by rock exfoliation?
He interprets the geometric angularity of scratches on the cave wall, such as cross-hatching, as 'meaning making'. For the non-specialist this seems plausible — until one sees Martinon's photographs of near-identical, but indisputably non-human, markings on other cave walls and across the dolomitic bedrock.
In 2017, the discovery of a second bone deposit in the 'Lesedi Chamber', 140m from the original excavation, strengthened the deliberate burial idea.
But it was later dealt a heavy blow by American geologist Kim Foecke, whose team, including Pickering, tried to replicate research intended to show the jumbling of sediments in and near supposed 'burial pits' in Rising Star.
They could find no meaningful variation.
Foecke's merciless judgment was that there was no geo-archaeological evidence for funerary practice and red-flag issues at every level of the research 'from design, acquisition of data and method choice, to data analysis, visualisation and interpretation'.
In this year's revision of Berger's paper, much of geochemical 'evidence' — a pillar of his original case — has allegedly been dropped.
Naledi could be much older than the fossil remains — in one scenario, its primitive traits place its origins near the base of the Homo family, implying little-changed survival over aeons, like the Indonesian 'Hobbit' (Homo floresiensis).
Alternatively, its 'derived' (more evolved) traits, such as feet, hands and lower limbs, may suggest a distant cousin of large-brained hominins such as Erectus and ourselves.
Gene transfer through 'introgression' is a complicating factor — instead of the linear ascent of successive species, evolution is increasingly seen as a moving tapestry of hybridisation.
Fired by a political animus and what constitutes good science, the 'Naledi Wars' show no immediate sign of abating. Sequencing its genome would lay some of the dust, but alas, the DNA seems hopelessly degraded.
In a field successively transformed over 50 years by technical leaps, enter 'palaeo-proteomics', the analysis of ancient proteins in crystalline tissue such as tooth enamel.
Could this unlock the Naledi riddle — and write the next chapter in the story of where we came from?