Category Archives: SOUTH AFRICA

Ancient Footprints Offer Evidence Humans Wore Shoes 148,000 Years Ago

Ancient Footprints Offer Evidence Humans Wore Shoes 148,000 Years Ago

A new analysis of ancient footprints in South Africa suggests that the humans who made these tracks might have been wearing hard-soled sandals.

Ancient Footprints Offer Evidence Humans Wore Shoes 148,000 Years Ago

Ichnological evidence from three palaeosurfaces on the Cape Coast, in conjunction with a neoichnological study, suggests that humans may indeed have worn footwear while traversing dune surfaces during the Middle Stone Age.

The study is published in the journal Ichnos.

While researchers are reluctant to shoehorn in any firm conclusions regarding the use of footwear in the distant past, the prints’ unusual characteristics may provide the oldest evidence yet that people used shoes to protect their feet from sharp rocks in the Middle Stone Age.

No direct dates have been assigned to the well-preserved markings found on stone slabs at three different sites along the Cape Coast, according to the study’s authors.

However, the researchers hypothesize that tracks discovered at a location known as Kleinkrantz may be between 79,000 and 148,000 years old based on the age of other nearby rocks and sediments.

The footprints show no toes, discerning it from barefoot markings, and instead displayed “rounded anterior ends, crisp margins, and possible evidence of strap attachment points.’ Similar markings that are estimated to have been left between 73,000 and 136,000 years ago were located at a site called Goukamma.

These prints can offer evidence early humans wore footwear 150,000 years ago.

The study authors wrote: “In all cases the purported tracks have dimensions that are broadly consistent with those of hominin tracks.” They added that the “track sizes appear to correspond to the tracks either of juvenile track-makers, or else small-adult hominin track-makers.”

To test this conclusion, the researchers made their own footprints wearing sandals resembling two different pairs of shoes used historically by the Indigenous San people of southern Africa, both of which are currently housed in museums.

Experiments revealed that the use of hard-soled footwear on wet sand left prints with crisp edges, no toe prints, and indentations where the leather straps met the sole – just like the markings at Kleinkrantz.

“While we do not consider the evidence conclusive, we interpret the three sites […] as suggesting the presence of shod-hominin trackmakers using hard-soled sandals,” write the researchers. Offering a possible motive for the use of such footwear, they go on to explain that coastal foraging involves clambering over sharp rocks while also posing the risk of stepping on sea urchins.

“In the [Middle Stone Age], a significant foot laceration might have been a death sentence,” they say. In this scenario, sandals would have been a lifesaver.

Despite their promising findings, researchers are reluctant to make any bold claims. This is due to a variety of factors, such as the difficulty of interpreting rock markings, as well as the fact no actual shoes from the Middle Stone Age have ever been found.

As such, they refrain from making major claims about their findings, but speculate that “humans may have indeed worn footwear while traversing dune surfaces during the Middle Stone Age.”

Journal Ichnos

Island in the Clouds: Is Mount Roraima Really A ‘Lost World’ Where Dinosaurs May Still Exist?

Island in the Clouds: Is Mount Roraima Really A ‘Lost World’ Where Dinosaurs May Still Exist?

Deep within the rainforests of Venezuela, a series of plateaus sit more than 9000 feet (2743 meters) above sea level and rise up 1310 feet (400 m) from the surrounding terrain like table tops. From above, they look like islands in the sky.

These are the tepuis (a Pemón Indian word for mountain), the most famous of which is called Mount Roraima. The tepuis are so unique in their geography that thousands of plant species exist nowhere else on the planet except on these plateaus.

The mystical mountains fascinated explorers and writers for centuries, most notably Sir Arthur Conan Doyle who described an ascent of Mount Roraima in his 1912 novel The Lost World .

In Doyle’s novel, a group of explorers found that dinosaurs and other extinct creatures were still alive and well on the remote plateaus. Some people today still believe this to be a real possibility.

An illustration from Doyle’s ‘Lost World’ in which explorers encounter dinosaurs atop Mount Roraima.

The Real Lost World

Once impenetrable to all but the Pemón indigenous people, Mount Roraima really was a lost world. The mountain plateaus were already established when South America was linked with Africa to form the supercontinent Gondwana, meaning they were first formed perhaps 400 to 250 million years ago.

During this time, molten rock forced its way up through cracks in the sandstone landmass. At the same time, wind and water swept across Gondwana to erode the raised highlands into mountain ranges. The region would come to look much like it does now around 20 million years ago.

Because the tepuis have been isolated for so long atop their high, lonely plateaus, the flora and fauna of the tepuis provide an organic illustration of the processes of evolution.

It is guessed that “at least half of the estimated 10,000 plant species here are unique to tepuis and surrounding lowlands. New species are still being discovered.” (George, 1989).

Although all of the tepuis have been climbed, only a few have been extensively explored. Could this mean that supposedly extinct species, even dinosaurs, may still exist atop these remote plateaus?

Island in the Clouds: Is Mount Roraima Really A ‘Lost World’ Where Dinosaurs May Still Exist?
Mount Roraima.

Could the Legends be Real?

The Roraima plateaus are so remote and so unique that it is not difficult to imagine Sir Arthur Conan Doyle creating a world alive with prehistoric plants and dinosaurs in his novel The Lost World . Doyle was fascinated with the accounts of British botanist Everard Im Thurn, who climbed to the top of Mount Roraima in December 1884.

Ascending Mount Roraima in 1989 for the National Geographic Society, German explorer Uwe George said, “None of us who followed Im Thurn to Roraima have found primordial creatures or their fossil remains there, but the terrain is so difficult that only a fraction of the tepui’s 44 square miles has so far been explored” (George, 1989). Since his writing, more of Mount Roraima has been investigated and, unsurprisingly, no traces of dinosaurs have been found.

It is not hard to imagine dinosaurs walking atop these remote and ancient lands, but no evidence has been found to suggest this could be the case.

Sacred Ground

Prior to the arrival of Europeans, the natives of Venezuela viewed the tepuis as having special mythical significance. According to the Pemón Indians, Mount Roraima is “the stump of a mighty tree that once held all the fruits and tuberous vegetables in the world,” however it was “felled by one of their ancestors, the tree crashed to the ground, unleashing a terrible flood” (Naeem, 2011). They believed that if a person ascended to the top of the tepuis, he or she would not come back alive.

A ‘Crystal Mountain Covered with Diamonds and Waterfalls’

Climbing the tepuis is exceedingly difficult and is made all the more so by the frequent rains that make the rocky footpaths slippery and muddy. The first European explorer to write about the tepuis was Sir Walter Raleigh in 1595. He wrote of a crystal mountain covered with diamonds and waterfalls.

There is a good chance that Sir Raleigh was describing Angel Falls, so named for the mid-20th century American Jimmie Angel who was the first person to fly over the area. Angel Falls were recently featured in Disney’s Up, where the falls are referred to as Paradise Falls.

A scene from Disney movie ‘Up’ showing ‘Paradise Falls’, which were based on Angel Falls at Mount Roraima.

There is a good chance that Sir Raleigh was describing Angel Falls, so named for the mid-20th century American Jimmie Angel who was the first person to fly over the area. Angel Falls were recently featured in Disney’s Up, where the falls are referred to as Paradise Falls.

Paleontologists say the world’s oldest-known burial site was found in South Africa

Paleontologists say the world’s oldest-known burial site was found in South Africa

Paleontologists say the world’s oldest-known burial site was found in South Africa

American explorer and scientist Lee Berger in South Africa said they have found the oldest-known burial site in the world, containing remains of a small-brained distant relative of humans previously thought incapable of complex behavior.

However, the scientist announced the discovery of a non-human species that uses symbols to mark their dead.

The researcher announced on Monday that he had evidence that Homo Naledi, a species with a brain the size of a chimpanzee, buried its dead and painted symbols on the walls of the tombs between 200,000 and 300,000 BC.

Researchers said they found the discovery buried about 30 meters (100 feet) below ground in a cave system at the Cradle of Humanity, a UNESCO world heritage site near Johannesburg.

“These are the most ancient interments yet recorded in the hominin record, earlier than evidence of Homo sapiens interments by at least 100,000 years,” the scientists wrote in a series of preprint papers, yet to be peer-reviewed, to be published in Life.

Paleontologist Lee Berger .

The findings cast doubt on the conventional wisdom regarding human evolution, which holds that the growth of larger brains enabled the performance of complex, “meaning-making” activities like burying the dead.

The oldest burials previously unearthed, found in the Middle East and Africa, contained the remains of Homo sapiens — and were around 100,000 years old.

“We are going to tell the world that we have discovered a non-human species, that had fire and controlled it, and went into incredibly difficult-to-reach spaces, and buried its dead in a ritual fashion, over and over and over again. And while they were doing that, they carved symbols on the wall above it”, said paleontologist Lee Berger.

Some experts however remain “sceptical” of his theory and require exceptional evidence to validate Berger’s claims.

Rising Star Cave.

In 2013, Lee Berger discovered the richest deposit of hominid fossils in Africa and introduced the world to Homo Naledi.

This species discovered by Dr. Berger had already upended the notion that our evolutionary path was a straight line, with curved fingers and toes, tool-wielding hands, and walking feet. Homo naledi is named after the “Rising Star” cave system where the first bones were found.

The holes, which researchers say evidence suggests were deliberately dug and then filled in to cover the bodies, contain at least five individuals. The oval-shaped interments at the center of the new studies were also found there during excavations started in 2018.

“That would mean not only are humans not unique in the development of symbolic practices, but may not have even invented such behaviours,” Berger told AFP in an interview.

The burial site is not the only sign that Homo naledi was capable of complex emotional and cognitive behavior, engravings forming geometrical shapes, including a “rough hashtag figure”, were also found on the apparently purposely smoothed surfaces of a cave pillar nearby.

What’s the oldest known case of cancer in humans?

What’s the oldest known case of cancer in humans?

What's the oldest known case of cancer in humans?
The first cancer case on record occurred 1.7 million years ago and was found in an early human relative’s toe bone.

Cancer may seem like a modern disease, but it has affected humans for eons. Scientists have discovered numerous prehistoric human remains indicating the presence of cancer. So, what’s the earliest case of cancer on record? And what’s the first time that humans wrote about it in medical texts?

The earliest evidence of human cancer comes from an early human relative who lived around 1.7 million years ago. This individual, likely of the species Paranthropus robustus or Homo ergaster, lived with a malignant tumor in their left toe bone.

Archaeologists discovered the skeletal remains inside Swartkrans cave, a limestone deposit in South Africa that’s often called the Cradle of Humankind for being home to the largest concentration of human relative remains in the world. 

When researchers compared computed tomography (CT) scans of the toe bone fossil with images of modern-day cases of osteosarcoma, an aggressive form of cancer that begins in the cells that form bones, they immediately recognized the distinctive cauliflower-like appearance of an osteosarcoma, according to a 2016 study about the case published in the South African Journal of Science.

Nowadays, osteosarcoma is one of the most common bone cancers in humans and can occur at any age, although it is most frequently seen in children, teenagers and young adults who are still growing, according to the American Cancer Society. However, while this prehistoric individual’s age is unknown, it appears that they were an adult, the researchers said. 

An even older benign tumor was found in a 1.9 million-year-old human relative known as Australopithecus sediba found in South Africa, according to a separate 2016 study in the South African Journal of Science.

It’s not surprising that the oldest known cancer case was in a bone, since organs, skin and other soft tissues are more prone to decay than bones are. 

“Bone is one of the few tissues that can survive in the fossil record,” Bruce Rothschild, a vertebrate paleontologist at the Carnegie Museum of Natural History in Pittsburgh who was not involved in the study, told Live Science.

However, even if cancer is present in a fossil, it often isn’t visible to the naked eye and takes further examination to find — which was the case for the toe bone.

“About one-third of cancers will show themselves,” Rothschild said. “But you would need to perform an X-ray to determine if something was hidden inside the bone. Most pathologists [today] look at an X-ray before coming up with a diagnosis of a tumor when it involves the bone.”

First written record of cancer

The Edwin Smith Papyrus from ancient Egypt is the first known text that mentions cancer.

Although the 1.7-million-year-old toe bone is the earliest known case of cancer in a hominin, a group that includes modern humans, the first written record of cancer doesn’t show up until much, much later.

In 3000 B.C. Imhotep — an ancient Egyptian mathematician, physician and architect — wrote what came to be known as the Edwin Smith Papyrus, a textbook about bodily trauma and surgical procedures. In the text, he detailed 48 medical cases, including several case studies on breast cancer.

The text was written in hieratic, an ancient Egyptian writing system, and was later translated into a two-volume English text by American archaeologist James Henry Breasted. In it, Imhotep described characteristics of different types of tumors, including “oily tumors” and “solid tumors.” He also included descriptions of a breast tumor  — describing it as “bulging mass in the breast” that is cool, hard and as dense as an “unripe hemat fruit” that spreads under the skin, according to the book “The Emperor of All Maladies: A Biography of  Cancer” (Scribner, 2010). 

While Imhotep gives a number of treatments for the other medical conditions in the text, under “therapy” for the breast tumor he wrote, “There is none.” However, he did note the best practices for binding other types of  tumors, which involved creating an ointment made of grease, honey and lint, according to The Cancer Letter, which published an excerpt of the historical text. 

The papyrus not only offers a glimpse of how surgical medicine was practiced thousands of years ago by ancient Egyptians, arguably some of the world’s first surgeons, but also provides some of the earliest evidence of cancer ever recorded, according to a 2016 study published in the journal Cancer. 

It’s unclear how these cases of prehistoric cancer developed. Just like the humans who came before us, we’re still trying to figure out what causes many cancers and the best ways to treat them.

Could Homo Naledi Control Fire?

Could Homo Naledi Control Fire?

An ancient hominid dubbed Homo naledi may have lit controlled fires in the pitch-dark chambers of an underground cave system, new discoveries hint.

Could Homo Naledi Control Fire?
An ancient southern African hominid called Homo naledi, represented here by a child’s partial fossil skull, possibly used fire sometime between 335,000 and 236,000 years ago, new cave finds suggest.

Researchers have found remnants of small fireplaces and sooty wall and ceiling smudges in passages and chambers throughout South Africa’s Rising Star cave complex, paleoanthropologist Lee Berger announced in a December 1 lecture hosted by the Carnegie Institution of Science in Washington, D.C.

“Signs of fire use are everywhere in this cave system,” said Berger, of the University of the Witwatersrand, Johannesburg.

H. naledi presumably lit the blazes in the caves since remains of no other hominids have turned up there, the team says. But the researchers have yet to date the age of the fire remains. And researchers outside Berger’s group have yet to evaluate the new finds.

H. naledi fossils date to between 335,000 and 236,000 years ago (SN: 5/9/17), around the time Homo sapiens originated (SN: 6/7/17). Many researchers suspect that regular use of fire by hominids for light, warmth and cooking began roughly 400,000 years ago (SN: 4/2/12).

Such behavior has not been attributed to H. naledi before, largely because of its small brain. But it’s now clear that a brain roughly one-third the size of human brains today still enabled H. naledi to achieve control of fire, Berger contends.

Last August, Berger climbed down a narrow shaft and examined two underground chambers where H. naledi fossils had been found. He noticed stalactites and thin rock sheets that had partly grown over older ceiling surfaces. Those surfaces displayed blackened, burned areas and were also dotted by what appeared to be soot particles, Berger said.

Meanwhile, expedition codirector and Wits paleoanthropologist Keneiloe Molopyane led excavations of a nearby cave chamber. There, the researchers uncovered two small fireplaces containing charred bits of wood, and burned bones of antelopes and other animals.

Remains of a fireplace and nearby burned animal bones were then discovered in a more remote cave chamber where H. naledi fossils have been found, Berger said.

Still, the main challenge for investigators will be to date the burned wood and bones and other fire remains from the Rising Star chambers and demonstrate that the material comes from the same sediment layers as H. naledi fossils, says paleoanthropologist W. Andrew Barr of George Washington University in Washington, D.C., who wasn’t involved in the work.

“That’s an absolutely critical first step before it will be possible to speculate about who may have made fires for what reason,” Barr says.

Bone, wood and charcoal from the South African site should also be examined with various techniques to determine whether darkened areas resulted from burning or mineral staining, says Harvard University archaeologist Sarah Hlubik, who wasn’t involved in the research. And a careful analysis of the layout of remains in the Rising Star chambers, she adds, will indicate whether Berger’s group discovered small fireplaces built by cave visitors, or only bones and other material that washed into the cave system.

Scientists discover 80,000-year-old bone tools

Scientists discover 80,000-year-old bone tools

Scientists discover 80,000-year-old bone tools
From left to right: experimental debarking in Africa, the bone tool tip after use, Francesco d’Errico making replicas of an experimental bone tool in the field.

Until the beginning of this century, the production of fully worked bone tools was considered an innovation introduced in Europe around 40,000 years ago by modern humans.

Research carried out over the last two decades has led to the discovery of bone tools in several regions of Africa, some of which could date back 100,000 years.

But these early bone tools are rare and non-standardised in shape.

Key cultural innovations

The discovery of 23 bone tools from the Sibudu rock shelter, Kwa Zulu-Natal, South Africa, all with a flattened ogival-shaped end, found in archaeological layers dated between 80,000 and 60,000 years ago, changes the picture.

“Our new study documents the technology and function of the earliest fully shaped bone tools from this region. The discovery of these tools contributes to a better understanding of when and how these innovations arose, and what they were used for,” Francesco d’Errico says. He is the lead author of the paper just published in Scientific Reports.

d’Errico is part of the SapienCE team at the University of Bergen. The SapienCE Centre of Excellence consists of an interdisciplinary team of world-leading scientists. The aim of SapienCE is to improve our understanding of how and when Homo sapiens evolved into who we are today.

Specialised tools for debarking activities

“Our results suggest that the Sibudu double-bevelled tools were not used for hunting or hide processing activities, which are tasks the earliest bone tools have been traditionally associated with, but rather for functions devoted to the exploitation of vegetal resources,” d’Errico explains.

The research was carried out by analysing the use of wear on archaeological and experimental tools with a confocal microscope. This allowed the researchers to measure the roughness parameters of the wear left on the tooltips by use.

Textural and discriminant analysis indicate that most of the bone tools discovered were used in debarking activities, and possibly for digging in humus-rich soil, likely to extract roots or underground storage organs.

Standardised cultural traits

The scientists note that this type of tool continued to be used at this site for 20,000 years, despite the fact that the occupants radically changed the way they produced stone tools during this period.

“These bone tools certainly reflect a local cultural adaptation to a specific environment, as we do not find them elsewhere. Our results support a scenario in which some modern human groups in southern Africa developed and maintained specific, highly standardised cultural traits locally while sharing others across the subcontinent,” d’Errico says.

Complex technical systems

This also implies that MSA peoples had networks allowing the sharing of similar technologies, cultural practices, and new innovations over large territories, while simultaneously maintaining local cultural traits and traditions.

This study confirms that Middle Stone populations already had complex technical systems to help them gather a variety of resources.

The bark of the trees on which the researchers conducted the debarking experiments is not edible but still used in traditional African medicine.

The bark may have been used already 80,000 years ago for similar purposes by Southern African early modern humans.

Early Human Evolution: Hominin Fossils in “Cradle of Humankind” May Be a Million Years Older Than Thought

Early Human Evolution: Hominin Fossils in “Cradle of Humankind” May Be a Million Years Older Than Thought

Early Human Evolution: Hominin Fossils in “Cradle of Humankind” May Be a Million Years Older Than Thought
Four different Australopithecus crania were found in the Sterkfontein caves, South Africa. The Sterkfontein cave fill containing this and other Australopithecus fossils was dated to 3.4 to 3.6 million years ago, far older than previously thought. The new date overturns the long-held concept that South African Australopithecus is a younger offshoot of East African Australopithecus afarensis. Credit: Jason Heaton and Ronald Clarke, in cooperation with the Ditsong Museum of Natural History

The Famous Sterkfontein Caves deposit is 1 million years older than previously thought.

New dates for the Australopithecus-bearing Sterkfontein Cave deposit place South African hominin fossils at the centre of global paleo research.

Nearly four million years of hominin and environmental evolution are revealed by fossils found at the Sterkfontein Caves in South Africa. Research began at the site in 1936 when Robert Broom discovered the first adult hominin of the genus Australopithecus.

Since then it has become famous for the hundreds of Australopithecus fossils yielded from excavations of ancient cave infills, including iconic specimens such as the Little Foot skeleton and the cranium known as Mrs. Ples.

Ancient cave infill called ‘Member 4’ is where the majority of Sterkfontein’s wealth of Australopithecus fossils have been excavated from. In fact, it is the richest deposit of Australopithecus fossils in the world.

Over the last 56 years of University of the Witwatersrand-led research at Sterkfontein, the age of Member 4 at Sterkfontein has remained contested. Age estimates have ranged from as young as about 2 million years ago, younger than the appearance of our genus Homo, back to about 3 million years.

New research presented in a paper published in the journal Proceedings of the National Academy of Sciences (PNAS) re-evaluates the age of Australopithecus from Member 4 at Sterkfontein together with the Jacovec Cavern, which contains a few additional hominin fossils in a deeper chamber in the cave.

“The new ages range from 3.4-3.6 million years for Member 4, indicating that the Sterkfontein hominins were contemporaries of other early Australopithecus species, like Australopithecus afarensis, in east Africa,” says Professor Dominic Stratford, director of research at the caves, and one of the authors on the paper.

The new ages are based on the radioactive decay of the rare isotopes aluminium-26 and beryllium-10 in the mineral quartz.

“These radioactive isotopes, known as cosmogenic nuclides, are produced by high-energy cosmic ray reactions near the ground surface, and their radioactive decay dates when the rocks were buried in the cave when they fell in the entrance together with the fossils,” says Professor Darryl Granger of Purdue University in the United States and lead author on the paper.

Previous dating of Member 4 has been based on dating calcite flowstone deposits found within the cave fill, but careful observations show that the flowstone is actually younger than the cave fill and so it underestimates the age of the fossils.

“This re-assessment of the age of Sterkfontein Member 4 Australopithecus fossils has important implications for the role of South Africa on the hominin evolution stage. Younger hominins, including Paranthropus and our genus Homoappear between about 2.8 and 2 million years ago.

Based on previously suggested dates, the South African Australopithecus species were too young to be their ancestors, so it has been considered more likely that Homo and Paranthropus evolved in East Africa,” says Stratford.

The new dates show that Australopithecus existed at Sterkfontein almost a million years prior to the appearance of Paranthropus and Homo, providing more time for them to evolve here, in the Cradle of Humankind, and placing the hominins from this site front and centre in the history early human evolution.

“This important new dating work pushes the age of some of the most interesting fossils in human evolution research, and one of South Africa’s most iconic fossils, Mrs. Ples, back a million years to a time when, in east Africa, we find other iconic early hominins like Lucy,” says Stratford.

“The redating of the Australopithecus-bearing infills at the Sterkfontein Caves will undoubtedly re-ignite the debate over the diverse characteristics of Australopithecus at Sterkfontein, and whether there could have been South African ancestors to later hominins,” says Granger.

For more on this research, read Fossils in the “Cradle of Humankind” May Be More Than a Million Years Older Than Thought.

Fossils in the ‘Cradle of Humankind’ may be more than a million years older than previously thought

Fossils in the ‘Cradle of Humankind’ may be more than a million years older than previously thought

A group of Australopithecus afarensis.

The ‘Cradle of Humankind’ is a UNESCO World Heritage Site in South Africa that comprises a variety of fossil-bearing cave deposits, including Sterkfontein Caves. Sterkfontein was made famous by the discovery of the first adult Australopithecus in 1936.

Since then, hundreds of Australopithecus fossils have been found there, including the well-known Mrs. Ples and the nearly complete skeleton known as Little Foot.

“Sterkfontein has more Australopithecus fossils than anywhere else in the world. But it’s hard to get a good date on them,” said Purdue University’s Professor Darryl Granger.

“People have looked at the animal fossils found near them and compared the ages of cave features like flowstones and gotten a range of different dates.”

“What our data does is resolve these controversies. It shows that these fossils are old — much older than we originally thought.”

Forensic facial reconstruction of Australopithecus afarensis.

To determine the age of the Australopithecus-bearing sediments at Sterkfontein, the researchers measured radioactive cosmogenic nuclides — aluminium-26 and beryllium-10 — in the mineral quartz.

“Cosmogenic nuclides are extremely rare isotopes produced by cosmic rays — high-energy particles that constantly bombard the Earth,” they explained.

“These incoming cosmic rays have enough energy to cause nuclear reactions inside rocks at the ground surface, creating new, radioactive isotopes within the mineral crystals.”

“An example is aluminum-26: aluminium that is missing a neutron and slowly decays to turn into magnesium over a period of millions of years.”

“Since aluminum-26 is formed when a rock is exposed at the surface, but not after it has been deeply buried in a cave, we can date cave sediments — and the fossils within them — by measuring levels of aluminium-26 in tandem with another cosmogenic nuclide, beryllium-10.”

Life reconstruction of Australopithecus sediba commissioned by the University of Michigan Museum of Natural History.

The team’s results show that the entire Australopithecus assemblage at Sterkfontein dates to 3.4-3.7 million years ago.

These australopiths were thus early representatives of the genus, overlapping in age with a morphologically diverse range of mid-Pliocene hominins, including Australopithecus afarensis and Australopithecus deyiremeda at Burtele, Australopithecus bahrelgazali in Chad, Kenyanthropus platyops at Lake Turkana, and Australopithecus anamensis at Woranso-Mille.

“The Sterkfontein hominins predate ParanthropusHomo, and Australopithecus sediba at nearby sites in the Cradle of Humankind by over a million years,” the authors said.

In addition to the new dates at Sterkfontein based on cosmogenic nuclides, they made careful maps of the cave deposits and showed how animal fossils of different ages would have been mixed together during excavations in the 1930s and 1940s, leading to decades of confusion about the previous ages.

“What I hope is that this convinces people that this dating method gives reliable results,” Dr. Granger said.

“Using this method, we can more accurately place ancient humans and their relatives in the correct time periods, in Africa, and elsewhere across the world.”

The results were published this week in the Proceedings of the National Academy of Sciences.