This article is from
Journal of Creation 37(1):80–86, April 2023

Browse our latest digital issue Subscribe

Developments in paleoanthropology no. 3

by Peter Line

New dates for Sterkfontein Australopithecus fossils

On 27 June 2022 Granger et al. published new dates for the Sterkfontein Australopithecus fossils from South Africa.¹ They used a method known as Cosmogenic Nuclide Burial Dating.² In a nutshell:

“The new ages are based on the radioactive decay of the rare isotopes aluminum-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 [from] 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.”³

This technique had earlier been used to date the Sterkfontein Australopithecus Little Foot skeleton (StW 573) to allegedly 3.7 Ma (million years ago).⁴ This date was subsequently disputed, with Pickering et al. suggesting a date of around 2.8 Ma “or possibly even more recent”.⁵ The Little Foot skeleton has been assigned to the species Australopithecus prometheus by its discover, Ronald Clarke,⁶ but it is likely just a variant of Australopithecus africanus.⁷ The date of Little Foot, along with the new dates for the other Australopithecus fossils (including Australopithecus africanus; see figure 1), yielded a combined range of supposedly about 3.4 to 3.7 Ma for the entire Australopithecus assemblage at Sterkfontein.⁸ This was allegedly a million years or so older than the ages, of about 2.1 to 2.6 Ma, attributed previously to most of the newly dated fossils (from Member 4).⁹ These ages are said to be determined from U-Pb and paleomagnetism dating of flowstones that Granger et al. believe are “stratigraphically intrusive within Member 4 and that they therefore underestimate the true age of the fossils.”⁹

Photo by Peter Line

The new age range overlaps with Australopithecus afarensis fossils (e.g. Lucy) and other alleged ‘hominins’ from East Africa and Chad.² Lucy’s species (Australopithecus afarensis) was long alleged to have been the prime contender for the ancestor of the human lineage.¹⁰ Now, the Sterkfontein Australopithecus assemblage competes with the East African ‘hominins’, particularly Australopithecus afarensis, as ancestors of later supposed hominins, including the genus Homo.¹¹ Basically, it is a competition between Australopithecus africanus and Australopithecus afarensis. However, from a creationist viewpoint, these and other australopithecines were not part of any evolutionary lineage, rather they were just part of a group of extinct apish primates, as explained in detail elsewhere.¹²

On how to resolve disagreements between different research teams on the ages of the Sterkfontein fossils, Charles Choi writes (quoting paleoanthropologist John Hawks):

“For example, scientists who want to solve the puzzle of the ages of these bones may take part in double-blind experiments involving ‘different groups of researchers examining the same samples, without knowing where they are from until they report their results,’ Hawks said. ‘Otherwise, there is too much potential for researchers to choose samples and methods that reinforce their own ideas.’”¹⁰

One wonders how many ages reported in the literature were selected because they reinforced the ideas of the researchers. Redating of fossils is not a rare occurrence. The new dates discussed above illustrate the fickle nature of age estimates obtained from dating methods.

Red Deer Cave people identified

In 2012, a study was published on the fossil remains, from Maludong (Red Deer Cave) and Longlin Cave in Southwest China, of what were dubbed the Red Deer Cave people.¹³ The human remains from the two localities were dated between allegedly ~11.5 and 14.5 ka (thousand years ago).¹⁴ The study was said to be “principally based on the remains of at least three individuals from Maludong”, which were excavated in 1989, as well as a partial skeleton from Longlin, discovered in 1979.¹⁵ Unusual features of the Red Deer Cave people included “a flat face, a broad nose, a jutting jaw that lacked a chin, large molar teeth, a rounded braincase with prominent brow ridges, and thick skull bones”.¹⁵ According to the analysis of the researchers, two plausible explanations for the morphology of the Red Deer Cave people were suggested:

“First, it may represent a late-surviving archaic population, perhaps paralleling the situation seen in North Africa as indicated by remains from Dar-es- Soltane and Temara, and maybe also in southern China at Zhirendong. Alternatively, East Asia may have been colonised during multiple waves during the Pleistocene, with the Longlin-Maludong morphology possibly reflecting deep population substructure in Africa prior to modern humans dispersing into Eurasia.”¹⁶

The study team were reluctant to call their find a new species, and other paleoanthropologists were skeptical the announced fossil human was evolutionarily unique or a new human group, which is likely why the National Geographic article had the ambiguous title: “Cave Fossil Find: New Human Species or ‘Nothing Extraordinary’?”.¹⁵

In late 2013 further analysis of the Maludong remains, including additional human cranial remains, were said by the researchers to “strengthen the affinities of the Maludong remains to archaic humans.”¹⁷ They wrote that:

“It seems unlikely that the Maludong remains simply represent very robust members of a late Pleistocene modern human population, perhaps people who acquired their archaic features through evolutionary reversal owing to isolation and random genetic drift.”¹⁸

Image: Darren Curnoe, Xueping Ji, Paul S. C. Taçon, and Ge Yaozheng / Wikimedia / CC BY-SA 4.0

Although the authors refrained from classifying the Maludong remains, they stated that “The most plausible scenario at present seems to be that the Maludong fossils along with those from Longlin cave … might represent a late surviving archaic population.”¹⁸

In July 2015, members of the research team published a paper further examining the Longlin 1 (LL 1) cranium (figure 2), in particular its shape, and concluded that “a scenario of hybridization with archaic hominins best explains the highly unusual morphology of LL1, possibly even occurring as late as the early Holocene.”¹⁹ Then, in December 2015, a femur from Maludong was described that they said “probably samples an archaic population that survived until around 14,000 ka ago in the biogeographically complex region of Southwest China.”²⁰ Team co-lead, Darren Curnoe, in an article in The Conversation, stated:

“Our work shows that the thigh bone strongly resembles very ancient species like early Homo erectus or Homo habilis, which lived around 1.5 million years ago or more in Africa.”²¹

Curnoe also noted that they were now treating the Longlin specimen as a “separate group, distinct from the bones from Red Deer Cave, or Maludong, and one that we now think is indeed very likely to be a hybrid.”²¹ Curnoe finished the article asking questions about the Red Deer Cave people, including “Just who exactly were these mysterious Stone Age people?”²¹ He also asked:

“What did modern humans make of them? And how did they interact with them when they encountered them? Did they interbreed with them?”²¹

Several years later answers to questions about the Red Deer Cave people were forthcoming, but perhaps not in the way expected by the researchers. It turns out they were modern humans. The team (Curnoe was not an author this time) published the results of an ancient DNA (aDNA) study in July 2022, where they reported on the genome sequencing of aDNA extracted from the calotte (skullcap) of a female Maludong specimen (MLDG-1704).²² According to the authors, their results indicated that MZR (the ‘Late Pleistocene hominin’ sequenced, i.e. MLDG-1704) “is a modern human who represents an early diversified lineage in East Asia.”²³

They further wrote that:

“MZR also shows a deep and indirect link to the ancestry that contributed to First Americans, which may help reconstruct the earliest migratory route from East Asia to the Americas.”²⁴

An article on the study from Cell Press stated:

“From the cave, researchers recovered a hominin skull cap with characteristics of both modern humans and archaic humans. For example, the shape of the skull resembled that of Neanderthals, and its brain appeared to be smaller than that of modern humans. As a result, some anthropologists had thought the skull probably belonged to an unknown archaic human species that lived until fairly recently or to a hybrid population of archaic and modern humans.”²⁵

One thing that can be learnt from the Red Deer Cave people saga is that humans should not be categorized as belonging to different human species based on morphological traits considered ‘archaic’. We know that Neanderthals and the mysterious Denisovans interbred with each other and with modern humans,²⁶ so these groups also belong with Homo sapiens. No aDNA has up to now been successfully sequenced from the so-called ‘archaic’ humans categorized as Homo erectus, but why should not these people also be categorized as Homo sapiens? It may well be the case that humans categorized as Homo erectus are Denisovans.

Bipedalism in gibbons

I have previously pointed out the logical fallacy that evolutionists engage in when they equate bipedal features in fossil primates in Africa, such as the australopithecines, with necessarily being a hominin (i.e. an apeman).²⁷ One justification for this criticism is the finding (from fossils) that apes/primates in Europe were likely built for some form of bipedalism and/or upright posture yet are not considered hominins.²⁸ Why, then, would bipedal features in the australopithecines from Africa mean they were hominins?

The Bible does not address the issue of locomotion in primates, and so, from a creation viewpoint, if bipedal apelike primates existed, it does not contradict Scripture. If God created humans bipedal, why would He not use variation on a similar design pattern for some other primates? Given how many non-human primates there are, if considering both extant and extinct species, it would in some ways seem a bit unusual if He had not. Hence, to the extent they were bipedal (which seems to have differed significantly from human-like bipedality), the australopithecines were likely one such primate group.

In the above context it is relevant mentioning that the lesser apes, the gibbons (Hylobatids; see figure 3), are apparently more bipedal than any of the great apes, which are supposedly closer to humans on the evolutionary tree.²⁹ According to Rosen et al.:

Photo by Peter Line

“Yet, we also cannot ignore these data demonstrating that hylobatids—the only primates in our study with a long lumbar region and an orthograde body posture, essential characteristics for upright walking in humans … —practice bipedal locomotion more frequently and for longer distances than the other non-human primates … .”³⁰

The authors also stated:

“These lines of evidence tentatively indicate that humans and hylobatids reflect the ancestral body form with respect to lumbar mobility and positional behaviour … . If true, then the short, stiff lumbar regions and correlated terrestrial knuckle-walking locomotion evolved in parallel in Pan and Gorilla as some have hypothesised”.³¹

Hence, if humans and gibbons have more in common with each other, in terms of upright posture and bipedalism, than they have with great apes like chimps, then that seems to make a very messy evolutionary scenario even more untenable.

Australopithecus sediba mandibular ramus update

A study by Rak et al., of the mandibles belonging to the two partial Australopithecus sediba skeletons (MH1 and MH2), concluded that “the specimens represent two separate genera: Australopithecus and Homo.”³² As discussed in an earlier article, the aspect of the mandibles examined was the upper ramal morphology, mainly the shape of the mandibular notch between the condylar process and coronoid process.³³

In response to this, Hawks and Berger later published an article where they highlighted “other fossil samples that show the same pattern of mandibular ramus variation as observed in MH1 and MH2.”³⁴ This included mandible fossil samples from the genus Homo,³⁵ likely of the same group and ‘species’ (whether Homo heidelbergensis or Homo erectus). According to the authors, the widespread variation of the ramus features used “makes them unsuitable to be used for taxonomic diagnosis on their own.”³⁶

Sahelanthropus tchadensis femur update

The Toumaï cranium, assigned to the species Sahelanthropus tchadensis and promoted in 2002 as the earliest known hominin, in my assessment appears to have belonged to an extinct ape/ape-like primate, with claims of bipedalism unsubstantiated.³⁷ From an evolutionary perspective a hominin is a species that is more closely related to humans than to chimpanzees.³⁸ I earlier discussed a study (Macchiarelli et al.³⁹) on a femur that may have belonged to Sahelanthropus tchadensis, and how, even from an evolutionary viewpoint, it poured more doubt on claims that Sahelanthropus tchadensis was bipedal and a hominin.⁴⁰ Since then, a different research team published a study on the same femur, as well as two ulnae, all likely associated with Sahelanthropus tchadensis. This species was said to be the only ‘hominin’ species identified in that location (TM 266), although it was also stated that “none of these limb bones can be reliably ascribed to any hominin craniodental specimen found at TM 266”⁴¹ (e.g. the Toumaï cranium). In summary, Daver et al. concluded:

“The morphology of the femur is most parsimonious with habitual bipedality, and the ulnae preserve evidence of substantial arboreal behaviour. Taken together, these findings suggest that hominins were already bipeds at around 7 Ma but also suggest that arboreal clambering was probably a significant part of their locomotor repertoire.”⁴¹

Writing on the find in Nature, Daniel Lieberman points out that a resolution on the bipedal statis of Sahelanthropus is not yet forthcoming:

“… because the femur consists mostly of a shaft that doesn’t have the joints at either end … that would provide most of the information needed to infer Sahelanthropus’s posture and how it walked.”⁴²

Lieberman commented that the authors of the study had “squeezed as much information as possible from the fossil data, focusing on features that they suggest are consistent with bipedalism.”⁴² However, Lieberman acknowledged that the “Sahelanthropus femur doesn’t have ‘smoking-gun’ traces of bipedalism, but it looks more like that of a bipedal hominin than that of a quadrupedal ape.”⁴²

Some evolutionary paleoanthropologists are not convinced that Sahelanthropus was a bipedal hominin. In an online Nature article Ewen Callaway quotes Bernard Wood as saying: “They cherry-pick what they think is information which is consistent with the femur shaft being a biped, and they studiously ignore information to the contrary”.⁴³ Roberto Macchiarelli, the first author of the earlier study of the Sahelanthropus femur, still thinks it more likely Sahelanthropus was an ape than a hominin.⁴³ Clare Wilson, writing for New Scientist, wrote in regard to Macchiarelli’s views on Sahelanthropus:

“But Macchiarelli isn’t convinced. This is partly because he says the angle the femur makes with the pelvis would be ‘mechanically unstable for a vertical stance’. Other primates that mainly walk on four legs occasionally stand up and walk on two, which could be why S. tchadensis has some features of bipedalism, says Macchiarelli. ‘There’s a bipedal signal in any primate,’ he says.”⁴⁴

Daver et al. made the following interesting comment:

“The multiplicity of attested and presumptive bipedalities currently proposed for several phylogenetically distinct hominoid taxa (for example, Orrorin, Ardipithecus, Australopithecus, Danuvius and Oreopithecus) strongly suggests that searching for a unique defining trait of bipedalism is hazardous (‘magic trait’ sensu …).”⁴⁵

The reality is that the finding of traits of bipedalism in several different extinct apes and/or primates that are not regarded as ‘hominins’ (e.g. Danuvius and Oreopithecus), and even in living apes, if gibbons are included in this category (see above), nullifies bipedal traits in fossil bones of extinct primates as evidence that they were supposed hominins. Lieberman states that the idea that “bipedalism evolved more than once among apes is thought by many to be unlikely”.⁴² I would add that bipedalism could not even have evolved once, given the complexities involved. The only way you can explain traits of bipedalism in different primates is by intelligent design.

Hence, regardless of the bipedal status of Sahelanthropus tchadensis, or lack thereof, it was simply an extinct ape/ape-like primate, not a hominin, the latter existing only as an evolutionary construct.

Homo naledi used fire

After promising a major announcement with respect to Homo naledi on 1 December 2022, paleoanthropologist Lee Berger, in a Carnegie Science talk, delivered.⁴⁶ He presented evidence for the use of fire in the Rising Star cave system, South Africa. The only supposed hominin remains known to have been found in this cave system are those attributed to Homo naledi. Hence, it is likely they were the users of fire. Berger believes Homo naledi individuals were the users of fire in the cave system, but he regards Homo naledi as a “truly non-human species”.⁴⁶

It was only after Berger lost enough weight (over 23 kg (50 lb)), allowing him for the first time to make it into the Dinaledi Chamber of the Rising Star cave system, that evidence for the use of fire was discovered. As told by Debora Patta:

“‘I looked up. And I realized the ceiling was black. It was burnt. It was covered in soot. It had been right above our heads the entire time,’ Berger said of his discovery.”⁴⁷

Patta continued to write:

“It’s undeniable evidence of fire. The same day, lead investigator and paleoanthropologist Keneiloe Molopyane was making another remarkable find nearby: ‘Pieces of bone … burnt bone’, she said, which indicated they were eating there.”⁴⁷

In the Lesedi chamber (where the Neo skeleton was found; see figure 4), as described by Sethchagi, the team “found burned rocks, with ashes at the bottom, and even further in, there was an abundance of burnt bone of small animals, and yet no signs of stone tools at all.”⁴⁸

Photo by Peter Line

According to the Bradshaw Foundation Homo naledi page:

“The expedition soon found evidence of fire use throughout the many passages and chambers, even within the most remote recesses of the cave system. Charcoal, ash and burnt bones had gone unnoticed in some chambers, as well as soot blackening on walls and ceilings. As Lee has commented, ‘We had blinded ourselves by thinking that evidence of fire was not there, but once our eyes were opened, the evidence for fire throughout the system wasn’t difficult to see at all, it was everywhere.’”⁴⁹

According to Berger,

“Everywhere there is a complex juncture, they built fire. Every adjacent cave system to the chambers where we believe they were disposing of the dead, they built fire and cooked animals, and in those chambers where they disposed of the dead, they brought fire but didn’t cook animals”.⁴⁶

So, does the finding that Homo naledi likely used fire affect current interpretations of this species? I have discussed the Homo naledi finds in much more detail elsewhere.^50,51,52,53 My interpretation of Homo naledi was that it likely consisted of Homo erectus-type ‘robust’ humans (descendants of Adam and Eve), some of whom suffered from a developmental pathology called cretinism. This could possibly explain some of the odd morphological features present in some of the fossil specimens. As such, nothing changes from my perspective. Rather, if they used fire, they were undoubtfully fully human. It need not necessarily have been the pathological individuals that used fire, but the healthier ones. If indeed they used fire, it makes it difficult to argue from a creation viewpoint that they were not fully human. Evolutionists in general believe Homo naledi to be a non-human species. If Homo naledi used fire to navigate the Rising Star cave system, as well as to cook food, then they will have to admit that it was much more intelligent than many had assumed.

There are issues that are of interest to both creationists and evolutionists. Particularly so is the date of the charcoal. In the talk Berger said they had previously dated charcoal from the Lesedi chamber (two pieces lying on the surface), and it “had given very young dates”, but the context was said to be terrible.⁴⁶ What happens if they use radiocarbon dating on charcoal directly associated with the use of fire by Homo naledi and it gives a very young age? Will they then say that the young age was proof of contamination, or that Homo naledi was not the fire maker, or accept the result at face value?

According to Alison George, “Dating of the charred remains is still underway, so the decision to announce the fire discovery in a talk on 1 December, prior to the publication of the formal scientific analysis, has proved controversial.”⁵⁴ Writing in The Washington Post, Mark Johnson gave the view of a past critic of Berger’s, paleoanthropologist Tim White, on the latest announcement:

“White said rigorous studies must date both the evidence of fire and the H. naledi [sic] bones if Berger’s team is to demonstrate that both come from the same period. Other studies must show not just the presence of fire, but its controlled use. Testing would need to establish that the material believed to be soot actually is soot and not discoloration caused by chemicals or other factors.”⁵⁵

As stated by Johnson,

“Berger acknowledged that one of the major challenges facing him and his colleagues will be dating the materials they’ve found. So far, they’ve said the H. naledi [sic] bones date to between 230,000 and 330,000 year [sic] ago, though Berger stressed that those dates should not be viewed as the first or last appearances of the species.”⁵⁵

Concerning implications of the find, George writes that,

“For Berger, the fire-use discovery has implications that are even more revolutionary. If these small-brained humans with many primitive features were capable of the complex cognition required to make and control fire, then ‘we’re beginning to see the emergence of a cultural pathway and behaviour that we thought, until this moment, was the domain of [Homo sapiens and Neanderthals],’ he says.”⁵⁴

Berger has promised further big announcements, so there is sure to be a lot more to come on Homo naledi.

Conclusions

From an evolutionary viewpoint, the Sterkfontein Australopithecus assemblage, after being assigned new dates, now competes with the East African ‘hominins’, particularly Australopithecus afarensis, as ancestors of later supposed hominins, including the genus Homo.

Rather than belonging to an unknown ‘archaic’ human species, or hybrid population of ‘archaic’ and modern humans, it turned out that the Red Deer Cave people from China were modern humans, as indicated by an aDNA study. The Red Deer Cave people saga cautions against categorizing humans as belonging to different human species based on morphological traits considered ‘archaic’.

If humans and gibbons have more in common with each other, in terms of upright posture and bipedalism, than they have with great apes like chimps, then that seems to make a very messy evolutionary scenario even more untenable.

The apparent widespread variation of ramus features in mandibles appears to make them unsuitable as a taxonomic diagnostic tool on their own.

The bipedal status of Sahelanthropus tchadensis is still doubted by some evolutionists, even after evidence in favor of bipedal features in its femur was published. Regardless of its bipedal status, or lack thereof, it was simply an extinct ape/ape-like primate, not a hominin, the latter existing only as an evolutionary construct.

If indeed Homo naledi used fire, it makes it difficult to argue from a creation viewpoint that they were not fully human. In other respects, the find raises new questions, such as the age of charcoal directly associated with fires attributed to Homo naledi.