Recently, a new creationist member of a Facebook group resorted to the familiar tactic of presenting the placenta as a complex organ that could not possibly have evolved. As so often with creationist arguments, this was little more than an argument from personal incredulity dressed up as a challenge. In place of scientific evidence, he relied on a god-of-the-gaps argument and a false dichotomy, implying that if he could not imagine a natural explanation, the only alternative must be magic performed by his preferred deity.
The new member appears to have left the group soon after replies began to appear in the comments, complete with links to articles and papers explaining exactly how the problem can be approached scientifically.
This paper in Nature by Oliver W. Griffith and Günter P. Wagner of Yale University provides precisely the sort of answer that exposes the weakness of this common creationist tactic on social media. Their argument amounts to little more than: “I do not know how this could have evolved, therefore God did it.” That is not an explanation; it is simply ignorance masquerading as evidence, and tells us more of the parochial ignorance of the creationist than they probably intended. The paper uses the evolution of the placenta to explain some basic principles of how complex organs evolved. Needless to say, no magic is involved anywhere in the process.
One of the authors, Oliver W. Griffith, has also written an article in The Conversation explaining their research and what it tells us about the evolution of complex organs in vertebrates. His article is reproduced here under a Creative Commons licence, reformatted for stylistic consistency.
First, a short explanation of the role of the placental in placental mammals:
If the transition from cold-bloodedness to warm-bloodedness is not a change in “kind” in the creationist sense, it is hard to imagine what would qualify. Creationists often try to dismiss major evolutionary transitions as mere “variation within a 'Kind'”, but the shift from ectothermy to endothermy was not some trivial adjustment. It was a profound physiological transformation that allowed animals to maintain a high, stable internal temperature, remain active across a wider range of conditions, and exploit ecological niches closed to their cold-blooded ancestors. Yet, according to creationist mythology, no such transition ever occurred, and there was never a point in time when it began.
Unfortunately for creationists, the evidence says otherwise. An international team of palaeontologists led by Ricardo Araújo of the Universidade de Lisboa, Lisbon, Portugal, Romain David of the Natural History Museum, London, UK, and Kenneth D. Angielczyk of the Field Museum of Natural History, Chicago, USA, believe they have identified when endothermy arose in the mammalian lineage. Their findings were published in Nature in July 2022. The team concluded that mammalian ancestors became warm-blooded about 233 million years ago, roughly 33 million years before the first true mammals appeared, and at about the same time that other recognisably mammalian traits such as fur and whiskers were evolving. The timing is consistent with evolutionary expectations that major innovations can arise in response to changing environmental pressures. [1.1]
They also concluded that this transition was rapid in geological terms, taking less than a million years rather than unfolding gradually over tens of millions of years, as had often been assumed. [2.1]
The researchers reached these conclusions by examining 3D models of the inner ears of dozens of mammalian ancestors, many from South Africa’s fossil-rich Karoo region. Karoo fossils are especially valuable because they preserve an exceptionally detailed record of synapsid evolution across almost 100 million years, documenting the transition from reptile-like therapsids to mammals. What the team focused on was the shape of the semicircular canals of the inner ear, which form part of the balance system. These canals are filled with endolymph, a fluid whose viscosity changes with temperature. As body temperature rose during the evolution of endothermy, the geometry of the canals had to change to keep the balance organ functioning properly. That gave the researchers a way to infer when warm-bloodedness first evolved in the mammalian line. [2.1]
Four of the authors of the paper in Nature also published an article in The Conversation explaining their results and their significance for understanding mammalian evolution. Their article is reproduced here under a Creative Commons licence, reformatted for stylistic consistency.
It is well established in evolutionary biology that mammals arose from within the synapsid lineage, the ancient group that includes the therapsids - stem-mammals that long predate true mammals. What had remained uncertain, however, was whether those early synapsids still reproduced by laying eggs, as modern monotremes such as the platypus and echidnas do, or whether live birth had evolved much earlier in the mammalian line.
That gap in our knowledge has now been narrowed dramatically and, no doubt to the acute discomfort of creationists, the evidence shows that about 250 million years ago - roughly 244 million years before young-Earth creationists believe the Earth was created - a therapsid was still reproducing by laying eggs. The evidence comes from a fossil embryo discovered in South Africa in 2008 by palaeontologist John Nyaphuli. Even more awkward for creationists, their mythology requires animals to have been created as separate, unrelated ‘kinds’, yet here we have direct evidence from the stem-mammal lineage showing a reproductive stage inherited from deep evolutionary ancestry rather than sudden, magical creation without predecessors.
Now Julien Benoit and Jennifer Botha of the University of the Witwatersrand, South Africa, together with Vincent Fernandez of the European Synchrotron Radiation Facility in Grenoble, France, have used high-resolution CT and synchrotron imaging to examine the curled-up embryo inside the rock and identify it as a young Lystrosaurus, a dicynodont therapsid from the Early Triassic. Crucially, the specimen preserves features consistent with an unhatched embryo, including a tightly curled in ovo posture and an unfused lower jaw symphysis. No calcified eggshell was preserved, so the egg was probably soft and leathery, as expected for a very early synapsid. Their findings are reported in an open access paper in PLOS One.
The authors have also co-authored an article in The Conversation explaining the discovery and its significance. Their article is reprinted here under a Creative Commons licence, reformatted for stylistic consistency.
he evidence presented in my last blog post suggested that, at least in the earlier phases of contact between anatomically modern humans moving out of Africa and the indigenous Neanderthals, interactions could be relatively peaceful, involving exchanges not only of DNA but also of technology and culture.
That may not always have been the case, however, as new evidence from the Troisième caverne of Goyet in Belgium suggests. Research just published in Scientific Reports by an international team including researchers from CNRS, the University of Bordeaux, and Aix-Marseille University indicates that, between 41,000 and 45,000 years ago, when Neanderthals were close to disappearing from Western Europe, a group consisting largely of non-local females and juveniles was taken to the Goyet site, butchered, and consumed. The broader background to this violence may have included growing territorial pressures, dwindling populations, or the increasing presence of Homo sapiens in nearby regions, but the precise cause remains unknown.
So, while we cannot know exactly what triggered this episode, and while the coincidence with the arrival of Homo sapiens may or may not be significant, isotope analysis does show that those who were cannibalised were outsiders rather than members of the local population.
For creationists, Neanderthals have always been a problem. It used to be common for them to claim that Neanderthals were known from just a single specimen later shown to be a pathological modern human suffering from arthritis. That falsehood has become harder and harder to sustain now that we have numerous specimens from across Eurasia, as well as sequenced Neanderthal genomes. The fallback position now seems to be to insist that Neanderthals fit neatly into Genesis because they were simply part of “human kind”.
Ken Ham, the creationist head of Answers in Genesis, with his characteristically casual regard for the truth and his obvious personal stake in presenting Bible-literalist mythology as history and science, has recently claimed that Neanderthals and Denisovans were descendants of Adam and Eve. What he does not explain, of course, is how he compresses the archaeological timescale of their existence, and their divergence into distinct lineages with markedly different genomes, into the 6,000 to 10,000 years allowed by creationist dogma. Like so many of Ham’s claims, it is aimed at an audience eager to have its prejudices confirmed and unlikely to fact-check anything for fear of discovering that it has been misled.
Like so much else in the history of life on Earth, and especially in the evolutionary history of our own species, all of this took place in that immense span of time before creationists imagine their small tribal god conjured up a small flat planet under a solid dome, conveniently centred on the Middle East.
The factual evidence, of course, tells a very different story: one based on testable, verifiable data, not on the campfire tales of Bronze Age herders who knew no better.
And in this case, that evidence shows that something, whether the increasing presence of modern Homo sapiens, the breakdown of Neanderthal society as their numbers declined, or some other factor entirely, led one Neanderthal group in what is now Belgium to capture outsiders, mainly women and children, bring them back to the Goyet site, and consume them.
Neanderthals are a persistent thorn in the side of creationism because they show that human origins are far older, messier and more interesting than the simplistic creation myths in the Bible. Genetic evidence shows that people outside Africa still carry a small but significant inheritance from Neanderthals, demonstrating that human ancestry was shaped not by descent from a single primordial couple, but by repeated episodes of migration, divergence and interbreeding between distinct human populations. There is even evidence that early Homo sapiens were interbreeding with Neanderthals as long as 100,000 years ago.
Now, new research by archaeologists and palaeoanthropologists from the Hebrew University of Jerusalem and Tel Aviv University, excavating at Tinshemet Cave in central Israel, suggests that the relationship between Neanderthals and early modern humans in the Levant, between about 130,000 and 80,000 years ago, involved far more than occasional contact. Their evidence indicates sustained interaction, shared technologies, similar hunting strategies and parallel ritual behaviour, including formal burial practices. The team have just published their findings in the journal Nature Human Behaviour. What emerges is a picture of different human groups living in close contact, exchanging ideas and behaviours to such an extent that their cultural differences became increasingly blurred.
The researchers reached this conclusion by integrating evidence from four main areas: stone-tool production, hunting strategies, symbolic behaviour and social complexity. Particularly striking is the clustering of burials at Tinshemet Cave, which suggests that the cave may have served as a repeated burial site, perhaps even an early cemetery. The placement of objects such as stone tools, animal bones and pieces of ochre in graves points to shared ritual practices and symbolic behaviour, hinting at a level of social and cultural complexity that creationist caricatures of early humans simply cannot accommodate.
In stark contrast to the simplistic Bronze Age mythology of the Bible, in which all humanity is supposedly descended from a single magically created couple with no ancestors just a few thousand years ago, followed by a biological reset in a global genocidal flood a mere 4,000 years ago, archaeology continues to reveal a far richer and more complex human story. Instead of a single recent origin, the evidence shows a deep evolutionary history stretching back hundreds of thousands of years, involving multiple related human species and regional populations, with occasional interbreeding. Part of that long history was played out in Eurasia.
A study led by scientists from the Spanish Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), just published in Quaternary International, has identified 400,000-year-old human artefacts at the Gran Dolina site in Atapuerca, Burgos, Spain, together with what may be the earliest evidence of communal hunting. The findings show the sophisticated manufacture of stone tools from locally available chert. The site is also associated with the remains of 60 bison, strongly suggesting a communal butchering site that implies strategic planning, cooperation, and large-scale social coordination.
What makes this especially striking is that these activities took place before the hominin lineage had diversified into Neanderthals, Denisovans, and modern humans. Taken together with other evidence from Atapuerca, including discoveries from Sima de los Huesos (‘Cave of Bones’), the findings indicate that archaic hominins such as Homo antecessor had established themselves in Iberia long before Homo sapiens entered Eurasia.
Scientists have recently announced the discovery of a small tooth in the Corral Bluffs, in the Denver basin, Colorado that shows one of the group of early mammals from which primates later emerged probably evolved in North America. For Creationists keen to find a reason to dismiss science and the evidence it keeps revealing showing creationism is nothing but an evidence free superstition, this is eerily reminiscent of what they regard as the 'Nebraska Man' hoax.
The supposed hoax was nothing of the sort and was, in reality a creationists lie intended to mislead people, perpetrated by two evangelical Christian con-men, Hank Hanegraff and Grant Jeffrey, who falsely proclaimed it to have been a failed attempt to trick people into believing in evolution - a trick that still has some success on creationists, notorious as they are for failing to fact-check their claims.
Creationists like to pretend that palaeontology is little more than a catalogue of embarrassing mistakes and hoaxes. In reality, of course, the history of palaeontology shows the opposite: new discoveries steadily refine and improve our understanding of life’s history, filling gaps in the fossil record and clarifying evolutionary relationships. A recent discovery reported in a press release by Taylor & Francis and described in a peer-reviewed paper in the Journal of Vertebrate Paleontology is a good example of this process at work.
The discovery concerns a few minuscule fossil teeth belonging to Purgatorius, a tiny, shrew-sized mammal that lived about 65.9 million years ago, shortly after the asteroid impact that wiped out the non-avian dinosaurs. Purgatorius is widely regarded as one of the earliest known relatives of the primate lineage—the group that eventually gave rise to monkeys, apes and humans. Fossils of this animal were previously known mainly from Montana and parts of western Canada, but the new finds from the Denver Basin in Colorado extend its known range several hundred miles further south.
According to the researchers, this discovery helps fill an awkward gap in the early fossil record of primate relatives. Slightly younger species appear in the southwestern United States about two million years later, leaving palaeontologists wondering why earlier forms seemed confined to the north. The Colorado fossils suggest that these early primate relatives probably spread southwards fairly rapidly after the mass extinction that ended the Cretaceous Period, diversifying as forests recovered in the aftermath of the impact.
However, before creationists begin sharpening their pencils in preparation for another round of “Nebraska Man” rhetoric, it is important to understand what this discovery does—and does not—show. The paper is not claiming that primates themselves evolved in North America, nor that this tiny mammal was a direct ancestor of humans. Purgatorius is better described as a stem relative of primates—an early member of the broader evolutionary group from which primates eventually emerged. In other words, it sits near the base of the evolutionary tree leading to primates, not within the modern primate group itself.
What the discovery really demonstrates is something far more typical of evolutionary biology: as new fossils are found, the geographical distribution and timing of early evolutionary lineages become clearer. In this case, a few teeth barely larger than grains of rice are helping palaeontologists reconstruct how the earliest primate relatives spread across ancient North America in the chaotic ecological world that followed the extinction of the dinosaurs.
Creationists refuse to recognise early hominins such as the australopithecines because they stubbornly refuse to conform to the creationist dogma that says there are no fossils showing the transition from a common ancestor with chimpanzees. Therefore, in the arrogant way creationists often deal with reality, because their stated dogma says otherwise, these fossils can't exist, and ad hoc explanations for their existence have to be invented — the dates are wrong; the scientists lied; Satan planted them to mislead us, etc., etc.
However, they do exist, and now scientists at the Centre national de recherche scientifique (CNRS), France, have succeeded in reconstructing the face of the australopithecine known as 'Little Foot', which was badly crushed and fragmented by the pressure and movement of the sediment in which it was buried. 'Little Foot', discovered at Sterkfontein, South Africa, is the most intact skeleton of an Australopithecus so far found, and this reconstruction helps place it in the evolutionary tree of the hominins as they diverged from the other African great apes. Their findings are published, open access, in the journal Comptes Rendus Palevol.
This reconstruction reveals a number of transitional features, just as one would expect of an early hominin roughly halfway in time between the split from the common ancestor with chimpanzees some 6 million years ago and the emergence of anatomically modern humans. But it also raises an intriguing question, because it appears to be closer to the East African australopithecines than to the South African australopithecines, raising questions about the evolutionary relationship between these two groups and the chronology of the evolution of the modern human face.
'Little Foot' was originally assigned to the species Australopithecus prometheus and later to Au. africanus, but is a school of thought that argues it is sufficiently different to other Australopiths to justify assigning it to a new species altogether.
Some of the first animals on Earth were likely ancestors of the modern sea sponge, according to MIT geochemists who unearthed new evidence in very old rocks.
Another fatal blow against creationism was revealed recently by geochemists led by Professor Roger E. Summons of the Massachusetts Institute of Technology (MIT), with news that they have found chemical evidence in ancient rocks suggesting that the earliest animals may have been the ancestors of sponges, living some 541 million years ago. Their findings have just been published in Proceedings of the National Academy of Sciences of the USA.
They succeeded in extracting the chemical signature of animal life from rocks in Oman, where they found an abundance of steranes that they determined were the preserved remnants of 30-carbon (C30) sterols — a rare form of steroid that they showed was most likely derived from ancient sea sponges known as demosponges.
Not only is this fatal to creationists' notion of Earth being just a few thousand years old, with all living organisms magically created without ancestry and with different “kinds” unrelated to other “kinds”, but it also delivers another hammer blow to the creationist parody of the so-called 'Cambrian Explosion' as a literal explosive creation of multiple body plans in a single event. Slightly more sophisticated creationists attempt to claim that this was the act of creation for which the tales in Genesis are merely a metaphor, with each day of 'creation week' representing millions of years — a claim that collapses on realisation that, according to Genesis, green plants would have had to exist for millions of years with no sun to drive photosynthesis, since the sun is supposedly created the 'day' after plants.
This analysis pushes the origins of the Cambrian biota back into the Ediacaran, showing not a sudden spontaneous creation 540 million years ago, but the cumulative products of evolutionary diversification, probably beginning with these early multicellular organisms.
In addition to Professor Roger E. Summons of MIT, the team included Dr Lubna Shawar of Caltech, Gordon Love of the University of California, Riverside, Benjamin Uveges of Cornell University, Alex Zumberge of GeoMark Research in Houston, Paco Cárdenas of Uppsala University in Sweden, and José-Luis Giner of the State University of New York College of Environmental Science and Forestry.
Long before anatomically modern Homo sapiens took their first tentative steps out of Africa and established themselves in Eurasia, an archaic hominin, Homo erectus, had already done so about a million years earlier, spreading across Asia into what is now the Indonesian archipelago and diversifying into a number of species and regional variants along the way.
One lineage settled on the island of Flores, where they encountered a miniature species of elephant, Stegodon florensis insularis, which probably became one of their principal sources of meat. By a process known to evolutionary biologists as Foster's Rule or the “island effect”, the descendants of these hominins also became smaller, eventually evolving into Homo floresiensis, popularly known as “The Hobbit” on account of their diminutive stature. Then, quite suddenly, they disappeared from history some 50,000 years ago.
Now an international team of archaeologists, including scientists from the University of Wollongong (UOW), Australia, believe they have found evidence explaining their extinction. It appears to have coincided with the disappearance of Stegodon florensis insularis and to have been driven by extensive climate change that began about 76,000 years ago, culminating in severe summer droughts between 61,000 and 50,000 years ago. The researchers reached this conclusion through analysis of the chemical record preserved in stalagmites from Flores caves, alongside isotopic data from the teeth of Stegodon. Their paper has just been published open access in Communications Earth & Environment.
A paper published recently in Science should give creationists something to think about. It shows how our close relatives, the bonobos, can imagine things completely detached from physical reality — rather like children playing games of pretend, or creationists pretending they are leading experts on biology and understand the subject better than the actual experts.
In this study, two researchers from Johns Hopkins University demonstrate that bonobos can engage in imaginative “pretend play”, an ability long assumed to be uniquely human. In doing so, they dismantle yet another supposed human-exclusive trait that creationists cite as evidence of special creation.
In one experiment with a captive bonobo, Kanzi — a 43-year-old individual living at Ape Initiative — a researcher pretended to pour juice from an empty jug into a transparent empty cup, and then pour it again into a second empty cup. When asked, “Where is the juice?”, Kanzi correctly identified the second cup.
In a similar experiment, an imaginary grape was taken from an empty bowl and placed into an empty jar. When asked, “Where is the grape?”, Kanzi again correctly pointed to the jar.
These experiments show that Kanzi was able to imagine and successfully track the movement of invisible, non-existent objects — something human children can typically do by the age of about two.
The discovery and dating (of which more later) of hominin remains in a Moroccan quarry, reported recently in Nature, has provided further confirmation that the origin of Homo sapiens lies in Africa, not Eurasia, contrary to an alternative hypothesis that has occasionally been proposed. The material consists of mandibles and other fragmentary remains, and also sheds light on the evolutionary origins of Neanderthals and Denisovans.
That is not to say that any serious palaeoanthropologists believed humans evolved wholly in Eurasia. Rather, some suggested that the final stages of Homo sapiens evolution may have occurred there, derived from descendants of earlier African migrants such as H. erectus, H. rhodesiensis, or H. antecessor. Others have argued that the so-called ‘muddle in the middle’ of the hominin family tree may represent a single, widely distributed species exhibiting regional variation across both Africa and Eurasia.
However, the Moroccan specimens display a clear mosaic of primitive and derived features — precisely the pattern that creationists call ‘transitional species’ and insist don't exist. These fossils combine traits seen in African sister lineages with features associated with H. antecessor, a pre-Neanderthal/Denisovan European species whose remains are being excavated at the Sima de los Huesos (Cave of Bones) site at Atapuerca, Spain.
The fossils are also exceptionally valuable for palaeoanthropology for another reason. The sediments in which they were found preserve the unmistakable signature of the Matuyama–Brunhes geomagnetic reversal, which occurred around 773,000 years ago when Earth’s magnetic poles flipped. This provides an unusually robust chronological anchor, as the timing of this reversal has been independently verified from multiple, entirely separate lines of evidence.
There is therefore a great deal here for creationists to attempt to dismiss. First, there is the mosaic of primitive and derived features that identify these fossils as genuinely transitional — something creationism insists does not exist. Second, there is the age of the material, securely dated to approximately 763,000 years (±4,000 years) before creationists insist Earth was magicked out of nothing, placing ancestral hominins hundreds of thousands of years before the Bronze Age biblical story of a single, ancestor-free human couple. Finally, and perhaps most inconveniently of all, the dating does not rely on radiometric methods at all, but on geomagnetic reversal stratigraphy, verified beyond any reasonable doubt. The biblical timeline is therefore wrong by many orders of magnitude.
A brief communication, published last November in the American Journal of Biological Anthropology may, if creationists never read past the title (as usual), have produced a frisson of excitement in those circles. It questioned the taxonomic status of one of the most complete fossil skeletons of an early ancestral hominin, Australopithecus prometheus, popularly known as “Little Foot”.
However, reading even a little further would have turned that excitement into disappointment — assuming, of course, that they understood what they were reading. The authors were not questioning whether the fossil was ancestral at all, but whether it had been assigned to the correct position in the hominin family tree, or whether it should instead be recognised as a distinct ancestral hominin species. In other words, this was a discussion about how many transitional species there are, not whether transitional species exist at all.
The only crumb of comfort available to creationists is the familiar claim that this demonstrates how science “keeps changing its mind”, something they take as evidence that science is fundamentally unreliable—presumably including even those parts they routinely misrepresent as supporting their beliefs.
For anyone who understands the scientific method, and the importance of treating all knowledge as provisional and contingent on the best available evidence, this paper represents the principle functioning exactly as it should. Far from being a weakness, this willingness to revise conclusions in the light of new information is what makes science self-correcting and progressively more accurate over time.
The authors of the paper — a team led by La Trobe University adjunct Dr Jesse Martin—carried out a new analysis of the “Little Foot” fossils and concluded that the specimen was probably placed in the wrong taxon when first described on the basis that it does not share the same “unique suite of primitive and derived features” as Australopithecus africanus. Since that initial assessment, additional fossils of A. prometheus have been discovered, and it has become clear that “Little Foot” also differs from those specimens. At the same time, it remains sufficiently distinct from A. africanus that reassignment to that species is not justified. In short, it possesses its own unique combination of primitive and derived traits and should therefore be recognised as a separate species.
Naturally, there is no real comfort here for creationists. The phrase “suite of primitive and derived features” is simply palaeontological shorthand for evidence of descent with modification—what Darwin referred to as transitional forms. It follows that the researchers involved have no doubt whatsoever that the species under discussion evolved from earlier ancestors, and there is no hint that they believe it was spontaneously created, without ancestry, by magic.
Photo montage of five major elements of DAN5 fossil cranium
Credit: Dr. Michael Rogers
Map showing potential migration routes of the human ancestor, Homo erectus, in Africa, Europe and Asia during the early Pleistocene. Key fossils of Homo erectus and the earlier Homo habilis species are shown, including the new face reconstruction of the DAN5 fossil from Gona, Ethiopia dated to 1.5 million years ago.
Credit: Dr. Karen L. Baab. Scans provided by National Museum of Ethiopia, National Museums of Kenya and Georgian National Museum.
Palaeontologists at the College of Graduate Studies, Glendale Campus of Midwestern University in Arizona, have reconstructed the head and face of an early Homo erectus specimen, DAN5, from Gona in the Afar region of Ethiopia on the Horn of Africa. In doing so, they have uncovered several unexpected features that should trouble any creationist who understands their significance. The research has just been published open access in Nature Communications.
Creationism requires its adherents to imagine that there are no intermediate fossils showing a transition from the common Homo/Pan ancestor to modern Homo sapiens, whom they claim were created as a single couple just a few thousand years ago with a flawless genome designed by an omniscient, omnipotent creator. The descendants of such a couple would, of course, show no genetic variation, because both the perfect genome and its replication machinery would operate flawlessly. No gene variants could ever arise.
The reality, however, is very different. Not only are there vast numbers of fossils documenting a continuum from the common Homo/Pan ancestor of around six million years ago, but there is also so much variation among them that it has become increasingly difficult to force them into a simple, linear sequence. Instead, human evolution is beginning to resemble a tangled bush rather than a neat progression.
The newly reconstructed face of the Ethiopian Homo erectus is no exception. It displays a mosaic of more primitive facial traits alongside features characteristic of the H. erectus populations believed to have spread out of Africa in the first of several waves of hominin migration into Eurasia. The most plausible explanation is that the Ethiopian population descended from an earlier expansion within Africa, became isolated in the Afar region, and retained its primitive characteristics while other populations continued to evolve towards the more derived Eurasian form.
The broader picture that has emerged in recent years—particularly since it became clear that H. sapiens, Neanderthals, and Denisovans formed an interbreeding complex that contributed to modern non-African humans—is one of repeated expansion into new environments, evolution in isolation, and subsequent genetic remixing as populations came back into contact. DAN5 represents just one of these populations, which appears to have evolved in isolation for some 300,000 years.
Not only is this timescale utterly incompatible with the idea of the special creation of H. sapiens 6,000–10,000 years ago, but the sheer existence of this degree of variation is also irreconcilable with the notion of a flawless, designed human genome. Even allowing for old-earth creationist claims that a biblical “day” may represent an elastic number of millions of years, the problem remains: a highly variable genome must still be explained as the product of perfect design. A flawless genome created by an omniscient, omnipotent creator should, moreover, have been robust enough to withstand interference following “the Fall” — an event such a creator would necessarily have foreseen, particularly if it also created the conditions for that fall and the other creative agency involved (Isaiah 45:7).
As usual, creationists seem to prefer the conclusion that their supposed intelligent creator was incompetent—either unaware of the future, indifferent to it, or powerless to prevent it—rather than accept the far more parsimonious explanation: that modern Homo sapiens are the product of a long, complex evolutionary history from more primitive beginnings, in which no divine intervention is required.
Origins of Homo erectus
Homo erectus
Homo erectus appears in the fossil record around 1.9–2.0 million years ago, emerging from earlier African Homo populations, most likely derived from Homo habilis–like ancestors. Many researchers distinguish early African forms as Homo ergaster, reserving H. erectus sensu stricto for later Asian populations, although this is a taxonomic preference rather than a settled fact.
Key features of early H. erectus include:
A substantial increase in brain size (typically 600–900 cm³ initially, later exceeding 1,000 cm³)
A long, low cranial vault with pronounced brow ridges
A modern human–like body plan, with long legs and shorter arms
Clear association with Acheulean stone tools and likely habitual fire use (by ~1 million years ago)
Crucially, H. erectus was the first hominin to disperse widely beyond Africa, reaching:
The Caucasus (Dmanisi) by ~1.8 Ma
Southeast Asia (Java) by ~1.6 Ma
China (Zhoukoudian) by ~0.8–0.7 Ma
This makes H. erectus not a single, static species, but a long-lived, geographically structured lineage.
Homo erectus as a population complex
Rather than a uniform species, H. erectus is best understood as a metapopulation:
African populations
Western Eurasian populations
East and Southeast Asian populations
These groups experienced repeated range expansions, isolation, local adaptation, and partial gene flow, producing the mosaic anatomy seen in fossils such as DAN5.
This population structure is critical for understanding later human evolution.
Relationship to later Homo species
Neanderthal (H. neanderthalensis)
From H. erectus to H. heidelbergensis
By around 700–600 thousand years ago, some H. erectus-derived populations—probably in Africa—had evolved into forms often grouped as Homo heidelbergensis (or H. rhodesiensis for African material).
These hominins had:
Larger brains (1,100–1,300 cm³)
Reduced facial prognathism
Continued Acheulean and early Middle Stone Age technologies
They represent a transitional grade, not a sharp speciation event.
Divergence of Neanderthals, Denisovans, and modern humans
Genetic and fossil evidence indicates the following broad pattern:
~550–600 ka: A heidelbergensis-like population splits
African branch → modern Homo sapiens
Eurasian branch → Neanderthals and Denisovans
Neanderthals
Evolved primarily in western Eurasia
Adapted to cold climates
Distinctive cranial morphology
Contributed ~1–2% of DNA to all non-African modern humans
Denisovans
Known mostly from genetic data, with sparse fossils (Denisova Cave)
Closely related to Neanderthals but genetically distinct
Contributed genes to Melanesians, Aboriginal Australians, and parts of East and Southeast Asia, including variants affecting altitude adaptation (e.g. EPAS1)
Modern Homo sapiens
Emerged in Africa by ~300 ka
Retained genetic continuity with earlier African populations
Dispersed out of Africa multiple times, beginning ~70–60 ka
Interbred repeatedly with Neanderthals and Denisovans
The key point: no clean branching tree
Human evolution is reticulate, not linear:
Species boundaries were porous
Gene flow occurred repeatedly
Populations diverged, adapted, re-merged, and diverged again
Homo erectus is not a side branch that “went extinct”, but a foundational grade from which multiple later lineages emerged. DAN5 fits neatly into this framework: a locally isolated erectus population retaining ancestral traits while others continued evolving elsewhere.
Why this matters
This picture:
Explains mosaic anatomy in fossils
Accounts for genetic admixture in living humans
Makes sense of long timescales and geographic diversity
Is incompatible with any model of recent, perfect, single-pair creation
Instead, it shows that our species is the outcome of millions of years of population dynamics, not a single moment of design.
A new fossil face sheds light on early migrations of ancient human ancestorA New Fossil Face Sheds Light on Early Migrations of Ancient Human Ancestor
A 1.5-million-year-old fossil from Gona, Ethiopia reveals new details about the first hominin species to disperse from Africa.
Summary: Virtual reassembly of teeth and fossil bone fragments reveals a beautifully preserved face of a 1.5-million-year-old human ancestor—the first complete Early Pleistocene hominin cranium from the Horn of Africa. This fossil, from Gona, Ethiopia, hints at a surprisingly archaic face in the earliest human ancestors to migrate out of Africa.
A team of international scientists, led by Dr. Karen Baab, a paleoanthropologist at the College of Graduate Studies, Glendale Campus of Midwestern University in Arizona, produced a virtual reconstruction of the face of early Homo erectus. The 1.5 to 1.6 million-year-old fossil, called DAN5, was found at the site of Gona, in the Afar region of Ethiopia. This surprisingly archaic face yields new insights into the first species to spread across Africa and Eurasia. The team’s findings are being published in Nature Communications.
We already knew that the DAN5 fossil had a small brain, but this new reconstruction shows that the face is also more primitive than classic African Homo erectus of the same antiquity. One explanation is that the Gona population retained the anatomy of the population that originally migrated out of Africa approximately 300,000 years earlier.
Dr. Karen L. Baab, lead author
Department of Anatomy
Midwestern University
Glendale, AZ, USA.
Gona, Ethiopia
The Gona Paleoanthropological Research Project in the Afar of Ethiopia is co-directed by Dr. Sileshi Semaw (Centro Nacional de Investigación sobre la Evolución Humana, Spain) and Dr. Michael Rogers (Southern Connecticut State University). Gona has yielded hominin fossils that are older than 6.3 million years ago, and stone tools spanning the last 2.6 million years of human evolution. The newly presented hominin reconstruction includes a fossil brain case (previously described in 2020) and smaller fragments of the face belonging to a single individual called DAN5 dated to between 1.6 and 1.5 million years ago. The face fragments (and teeth) have now been reassembled using virtual techniques to generate the most complete skull of a fossil human from the Horn of Africa in this time period. The DAN5 fossil is assigned to Homo erectus, a long-lived species found throughout Africa, Asia, and Europe after approximately 1.8 million years ago.
How did the scientists reconstruct the DAN5 fossil?
The researchers used high-resolution micro-CT scans of the four major fragments of the face, which were recovered during the 2000 fieldwork at Gona. 3D models of the fragments were generated from the CT scans. The face fragments were then re-pieced together on a computer screen, and the teeth were fit into the upper jaw where possible. The final step was “attaching” the face to the braincase to produce a mostly complete cranium. This reconstruction took about a year and went through several iterations before arriving at the final version.
Dr. Baab, who was responsible for the reconstruction, described this as “a very complicated 3D puzzle, and one where you do not know the exact outcome in advance. Fortunately, we do know how faces fit together in general, so we were not starting from scratch.”
What did scientists conclude?
This new study shows that the Gona population 1.5 million years ago had a mix of typical Homo erectus characters concentrated in its braincase, but more ancestral features of the face and teeth normally only seen in earlier species. For example, the bridge of the nose is quite flat, and the molars are large. Scientists determined this by comparing the size and shape of the DAN5 face and teeth with other fossils of the same geological age, as well as older and younger ones. A similar combination of traits was documented previously in Eurasia, but this is the first fossil to show this combination of traits inside Africa, challenging the idea that Homo erectus evolved outside of the continent.
I'll never forget the shock I felt when Dr. Baab first showed me the reconstructed face and jaw. The oldest fossils belonging to Homo erectus are from Africa, and the new fossil reconstruction shows that transitional fossils also existed there, so it makes sense that this species emerged on the African continent,” says Dr. Baab. “But the DAN5 fossil postdates the initial exit from Africa, so other interpretations are possible.
Dr. Yousuke Kaifu, co-author
The University Museum
The University of Tokyo
Bunkyo-ku, Tokyo, Japa.
This newly reconstructed cranium further emphasizes the anatomical diversity seen in early members of our genus, which is only likely to increase with future discoveries.
Dr. Michael J. Rogers, co-author.
Department of Anthropology
Southern Connecticut State University
New Haven, CT, USA.
It is remarkable that the DAN5 Homo erectus was making both simple Oldowan stone tools and early Acheulian handaxes, among the earliest evidence for the two stone tool traditions to be found directly associated with a hominin fossil.
Dr. Sileshi Semaw, co-author
Centro Nacional de Investigación sobre la Evolución Humana (CENIEH)
Burgos, Spain.
Future Research
The researchers are hoping to compare this fossil to the earliest human fossils from Europe, including fossils assigned to Homo erectus but also a distinct species, Homo antecessor, both dated to approximately one million years ago.
Comparing DAN5 to these fossils will not only deepen our understanding of facial variability within Homo erectus but also shed light on how the species adapted and evolved.
Dr. Sarah E. Freidline, co-author
Department of Anthropology
University of Central Florida
Orlando, FL, USA.
There is also potential to test alternative evolutionary scenarios, such as genetic admixture between two species, as seen in later human evolution among Neanderthals, modern humans and “Denisovans.” For example, maybe DAN5 represents the result of admixture between classic African Homo erectus and the earlier Homo habilis species.
We’re going to need several more fossils dated between one to two million years ago to sort this out.
Abstract
The African Early Pleistocene is a time of evolutionary change and techno-behavioral innovation in human prehistory that sees the advent of our own genus, Homo, from earlier australopithecine ancestors by 2.8-2.3 million years ago. This was followed by the origin and dispersal of Homo erectus sensu lato across Africa and Eurasia between ~ 2.0 and 1.1 Ma and the emergence of both large-brained (e.g., Bodo, Kabwe) and small-brained (e.g., H. naledi) lineages in the Middle Pleistocene of Africa. Here we present a newly reconstructed face of the DAN5/P1 cranium from Gona, Ethiopia (1.6-1.5 Ma) that, in conjunction with the cranial vault, is a mostly complete Early Pleistocene Homo cranium from the Horn of Africa. Morphometric analyses demonstrate a combination of H. erectus-like cranial traits and basal Homo-like facial and dental features combined with a small brain size in DAN5/P1. The presence of such a morphological mosaic contemporaneous with or postdating the emergence of the indisputable H. erectus craniodental complex around 1.6 Ma implies an intricate evolutionary transition from early Homo to H. erectus. This finding also supports a long persistence of small-brained, plesiomorphic Homo group(s) alongside other Homo groups that experienced continued encephalization through the Early to Middle Pleistocene of Africa.
Introduction
The oldest fossils assigned to our genus are ~2.8 million years old (Myr) from Ethiopia and signal a long history of Homo evolution in the Rift Valley1,2,3. There is evidence of multiple Homo lineages in Africa by 2.0–1.9 million years ago (Ma) and an archaeological and paleontological record of expansion to more temperate habitats in the Caucasus and Asia between 2.0 and 1.8 Ma4 (Fig. 1). The last appearance datum for the more archaicHomo habilis species (or “1813 group”) is ~1.67 (OH 13) or ~1.44 Ma, if KNM-ER 42703 is correctly attributed to H. habilis5, which is uncertain6. The archetypal early African Homo erectus fossils from Kenya (i.e., KNM-ER 3733, 3883; and the adolescent KNM-WT 15000) already present a suite of traits that distinguish them from early Homo taxa by 1.6–1.5 Ma, including larger brains and bodies, smaller postcanine dentition, more pronounced cranial superstructures (e.g., projecting and tall brow ridges), a relatively wide midface and nasal aperture, deep palate, and projecting nasal bridge1,6,7,8,9,10,11. The only evidence for H. erectus sensu lato in Africa before 1.8 Ma are fragmentary or juvenile fossils12,13,14, while fossils expressing both ancestral H. habilis and more derived H. erectus s.l. morphological traits are only known from Dmanisi, Georgia at 1.77 Ma15,16. Thus, H. erectus emerged from basal Homo between 2.0 and 1.6 million years ago, but when, where (Africa or Eurasia), and how it occurred remain unclear. An expanded fossil record also documents significant variation in endocranial 17,18 and craniofacial6,8 and dentognathic morphology19,20 throughout the Early Pleistocene, which extends to the Middle Pleistocene with the addition of small-brained Homo lineages to the human tree.
Fig. 1: Early Homo and Homo erectus timeline between 2.0 and 1.0 Ma and map of key sites in Africa and southern Eurasia.
The solid bars of the timeline indicate well-established first and last appearance data; the horizontal stripes indicate possible extensions of the time range based on fragmentary or juvenile fossils. Diagonal lines signal earlier archaeological presence in those regions. The question mark indicates a possible date of <1.49 Ma for the Mojokerto, Indonesia site cf.22,23,24,25. The horizontal gray bar represents the time range associated with DAN5/P1. Colors on the map indicate presence of fossils matching taxa or geographic groups of H. erectus as indicated in the timeline. Surface renderings of the best-preserved regional representatives of archaic or small-brained Homo fossils (beginning at top and continuing clockwise): D2700, KNM-ER 1813, KNM-ER 1470, KNM-ER 3733, SK 847, OH 24, KNM-WT 15000, and DAN5/P1. All surface renderings visualized at FOV 0° (parallel). Map was generated in “rnaturalearth” package68 for R.
The initial announcement of DAN5/P1 assigned it to H. erectus on the basis of derived neurocranial traits21. Subsequent analyses of neurocranial shape and endocranial morphology confirmed affinity with H. erectus but also noted similarities to early (pre-erectus) Homo fossils such as KNM-ER 181317,18. Only limited information about the partial maxilla and dentition was presented in the original description21. Yet, facial and dental traits are increasingly important in early Homo systematics, given overlap in brain size among closely related hominins6,8,22. The DAN5/P1 fossil is a rare opportunity to evaluate neurocranial, facial, and dental anatomy in a single Early Pleistocene Homo fossil and thus has significant implications for this discussion.
Here we present a new cranial reconstruction of the 1.6–1.5 Myr DAN5/P1 fossil from Gona, Ethiopia. This study demonstrates that the small-brained adult DAN5/P1 fossil (598 cm321) presents a previously undocumented combination of early Homo and H. erectus features in an African fossil.
Taken together, the evidence leaves little room for the idea that Homo erectus was a dead-end curiosity, neatly replaced by something entirely new. Instead, it represents a long-lived, widely dispersed, and internally diverse population complex that provided the evolutionary substrate from which later human lineages emerged. Its descendants were not produced by sudden leaps or special creation events, but by the ordinary, observable processes of population divergence, isolation, and adaptation acting over deep time.
Modern Homo sapiens, Neanderthals, and Denisovans did not arise as separate “kinds”, nor did they follow clean, branching paths. They represent regional outcomes of this erectus-derived heritage, shaped by geography, climate, and repeated episodes of contact and interbreeding. The genetic legacy of those interactions is still present in living humans today, providing independent confirmation of what the fossil record has long been indicating.
What emerges is not a ladder of progress but a dynamic, reticulated history: populations spreading, fragmenting, evolving in isolation, and reconnecting again. Fossils such as DAN5 are not anomalies to be explained away; they are exactly what we should expect from evolution operating on structured populations across continents and hundreds of thousands of years.
For creationism, this is deeply inconvenient. For evolutionary biology, it is precisely the kind of rich, internally consistent picture that arises when multiple independent lines of evidence converge on the same conclusion: humanity is the product of a long, complex evolutionary history, not a recent act of design.
A newly published paper in Proceedings of the Royal Society B by researchers from University College London (UCL) shows that the human skull evolved relatively rapidly compared to that of other apes. The evolutionary changes involve modifications in the size and shape of the facial and cranial bones.
This serves as a reminder of just how artificial and functionally useless the creationist concept of a “kind” is. It should also show creationists the fallacy of the frequent claim that biologists are abandoning the Theory of Evolution, since this paper discusses the results of evolution, not some infantile notion of magical intervention by an unevidenced supernatural entity.
Creationists are quite content to regard all cats—from domestic tabbies to tigers—as belonging to the same “kind”, even though the main difference between them lies in the size of their skeletons. Yet they balk at the idea that humans and the great apes could belong to the same “kind”, despite the fact that the key distinctions between us and them are also differences in size and proportion—most notably in the bones of the skull.
But then, “kind” is precisely the sort of term creationists favour because it has no fixed definition and can be expanded or contracted to suit whatever argument they are trying to make. The only consistent rule seems to be that whatever constitutes a “kind”, it must always exclude humans. This sometimes leads to the absurdity of defining an “animal kind” and a separate “human kind”.
The UCL team suggest that the rapid evolution of the human skull can be explained by the considerable advantage conferred by a larger brain and advanced cognitive abilities.
Our complex cognition allows us to communicate abstract ideas through both words and gestures—what we call “body language”—much of which depends on facial expression. A flat, forward-facing face enhances our ability to convey and interpret these subtle cues. As social animals, we identify acquaintances and strangers by their faces; we watch the faces of those who speak to us; and we instinctively read emotions such as pleasure, anger, confusion, or distress in their expressions.
In short, it is our large brain and expressive face that make us human — not the addition of new organs or limbs, as creationists often insist marks a change above the genus level, but rather differences in the size and shape of the bones of the skull. Given the close similarity of our genomes to those of other apes, these differences arise not from the amount of genetic information, but from the way that information is regulated during embryonic development.
A recent archaeological finding, by Beniamino Mecozzi of Sapienza University of Rome, Italy and colleagues, at the site of Casal Lumbroso in northwest Rome, has once again refuted the Bible narrative by extending the known depth of human prehistory far beyond the limits imposed by biblical literalism.
In sediments dated to some 400,000 years before creationism’s mythical 'Creation Week', the research team has uncovered evidence that early humans were butchering elephants with small stone tools and then fashioning large implements from the animals’ bones. These traces of planning, adaptation, and technological innovation demonstrate that human ingenuity was already well advanced hundreds of millennia before the supposed creation of Adam.
More interestingly from a scientific perspective is not the incidental refutation of ancient creation myths, which happens with almost every archaeological and palaeontological discovery, but the fact that these hominins predate the successful Homo sapiens migration out of African and into Eurasia by tens of thousands of years and pre-date even the earliest evidence of Neanderthals in western Eurasia.
Such discoveries highlight the sheer scale of time over which our lineage evolved—an evolutionary saga measured not in millennia but in hundreds of thousands of years. The people who left these marks were not modern humans, but archaic members of the genus Homo, close relatives or ancestors of the Neanderthals. Their world was already ancient when the earliest chapters of Genesis were imagined.
The day creationists dread — the final closure of their favourite god-shaped abiogenesis gap — moved a little closer last May, when scientists at University College London (UCL) announced that they had shown how the first RNA could have reproduced. In a selective environment with competition for resources, this would have led inevitably to ever-increasing efficiency in replication, kick-starting the whole evolutionary process and the emergence of self-organising systems (or “life”) from prebiotic precursors (or “non-life”). This is, of course, the very process that creationists insist is “impossible”, clinging to the idea that “life” is some magical essence that must be granted by a supernatural deity.
When this God-shaped gap is finally and conclusively closed — as all the others have been — creationists will need to scramble once again to reframe their beliefs and cling to whatever shrinking space remains for their god. Just as their old claim that evolution was “impossible” collapsed, to be replaced with notions of a short burst of warp-speed evolution “within kinds” after “The Flood” (and supposedly still happening today, but conveniently “guided” by God), so too will abiogenesis inevitably be rebranded as yet another process directed by divine intention — naturally, with the eventual production of (American) humans as the goal.
