— Researchers report the first hominin remains from a poorly documented interval of human evolution: a cluster of bones and teeth recovered at Grotte à Hominidés, Thomas Quarry, near Casablanca, Morocco, dated to 773,000 years ago. The assemblage includes three jawbones (one juvenile), isolated teeth, vertebrae and a femur, and was dated using paleomagnetism tied to the Matuyama–Brunhes reversal. The fossils show a mosaic of primitive and derived traits — no clear chin, yet dental features resembling those of Homo sapiens and Neanderthals — and may illuminate the ancestry of Neanderthals, Denisovans and modern humans. Scientists caution the remains are not yet assigned a formal species name but offer a rare window into a previously empty interval between about 1 million and 500,000 years ago.
Key takeaways
- The fossils were excavated at Grotte à Hominidés in Thomas Quarry, Casablanca; most were recovered in 2008–2009 and have now been dated to 773,000 years ago using paleomagnetic evidence.
- Dating ties the layer to the Matuyama–Brunhes geomagnetic reversal, a global chronological marker approximately 773,000 years before present.
- The assemblage comprises three jawbones (including a child), multiple teeth, vertebrae and a femur bearing likely hyena bite marks, indicating carnivore activity at the site.
- CT and morphological analysis show a mix of primitive and more modern features: absence of a defined chin but dental characters approaching Homo sapiens and Neanderthals.
- Authors stop short of naming a new species; they note resemblances to Homo erectus combined with traits consistent with direct ancestors of later humans.
- Genetic estimates place the last common ancestor of Neanderthals, Denisovans and Homo sapiens between about 550,000 and 765,000 years ago, overlapping the age of these Moroccan remains.
- These fossils are the first hominin material from this specific mid-Pleistocene interval in Africa, potentially filling a critical gap in the fossil record between ~1 million and ~500,000 years ago.
Background
Africa has an extensive hominin fossil record up to roughly 1 million years ago and then a relative scarcity until about 500,000 years ago; that interval has long frustrated attempts to trace how archaic forms gave rise to later lineages. The newly dated Moroccan remains sit squarely within that interval, offering material from a time when genetic data infer a branching of major human lineages. The region around Casablanca is already archaeologically significant: Jebel Irhoud, also in Morocco, yielded some of the earliest known Homo sapiens fossils dated to about 400,000 years ago, though researchers caution that preservation conditions rather than geographic origin likely drive the abundance of finds there.
Paleomagnetism — the method used to date the Moroccan layer — records changes in Earth’s magnetic field preserved in minerals and can pin deposits to global polarity transitions. The Matuyama–Brunhes reversal is a widely used chronological marker at 773,000 years ago, which gave the team a tightly constrained age for the deposit. The find comes from a cave context that also shows strong evidence of carnivore activity, including tooth marks on the femur, indicating these hominins shared space or carcasses with predators such as hyenas.
Main event
The skeletal material recovered at Thomas Quarry includes three mandibles (one juvenile), several isolated teeth, vertebral fragments and a partial femur. Excavations in 2008 and 2009 produced most of this material; the research team later applied paleomagnetic analyses and stratigraphic work to date the layer precisely. The paleomagnetic signature of the deposit matched the Matuyama–Brunhes transition, anchoring the assemblage at 773,000 years ago.
Morphological study used CT scanning and comparative metrics to evaluate traits. Researchers report a mosaic anatomy: the lower jaws lack a modern human chin, a primitive trait, but the teeth and some dental features resemble those seen in later Homo populations, including Neanderthals and Homo sapiens. That combination complicates simple lineage assignments and suggests a transitional or regionally variable population.
The femur shows puncture and scoring consistent with carnivore gnawing; context also includes other indicators of carnivore occupation of the cave. The taphonomic evidence implies that at least some bones were exposed to scavengers, complicating interpretation of whether the cave was a habitation site, a carnivore den, or a place of intermittent hominin use and predator activity.
Study authors do not assign a formal species name. Instead, they emphasize the specimens’ significance as direct physical evidence from a period otherwise known mainly from sparse fragments or inferred from genetics. The material is discussed alongside candidates for the ancestral population that gave rise to Neanderthals, Denisovans and modern humans, such as Homo antecessor and Homo heidelbergensis, while noting morphological overlap with Homo erectus.
Analysis & implications
The Moroccan fossils reduce a critical temporal gap in the African fossil record and thus tighten constraints on models of Middle Pleistocene evolution. If these individuals are representative of regional populations near 773,000 years ago, they document anatomical variation at a time when genetic syntheses place the divergence of the three lineages that led to Neanderthals, Denisovans and modern humans. That coincidence strengthens the possibility that transitional populations in Africa contributed materially to later splits and gene flow patterns.
The mosaic anatomy underscores that human evolution during the Middle Pleistocene was not a simple, linear replacement of primitive by modern features; instead, populations combined ancestral and derived traits in ways that could reflect regional adaptation, population structure, and episodic contact between groups. This complexity challenges researchers to integrate fossil morphology, ancient DNA where available, and archaeological context to reconstruct population dynamics across continents.
Geographic interpretation requires caution. The presence of both early Homo sapiens at Jebel Irhoud (about 400,000 years ago) and these much older remains in Morocco does not imply a single North African cradle for our species. Preservation bias, local geology and sampling intensity strongly affect where fossils survive and are discovered. Nevertheless, the new find highlights North Africa’s role as a place where critical evidence for human evolution can be recovered.
Comparison & data
| Feature | Approx. age (yrs) | Representative site |
|---|---|---|
| New Moroccan hominins | 773,000 | Thomas Quarry, Grotte à Hominidés |
| Earliest Homo sapiens (Morocco) | ~400,000 | Jebel Irhoud |
| Genetic estimate: last common ancestor | 550,000–765,000 | Genomic studies |
| Major geomagnetic reversal | 773,000 | Matuyama–Brunhes |
Placing the Moroccan fossils alongside key chronological markers shows their temporal overlap with genetic estimates for the ancestor of later human groups. The Matuyama–Brunhes tie yields a tighter absolute age than many Middle Pleistocene finds, improving comparisons across sites and disciplines. Still, sample size is small and morphological overlap among candidate species complicates taxonomic assignment; further discoveries and integrated analyses will be required to test evolutionary scenarios.
Reactions & quotes
Several specialists not involved in the work placed the find in context and urged caution about sweeping claims while noting the discovery’s potential to inform models of human ancestry.
There are a lot of fossil hominins in Africa until about a million years ago, but then after that there is a jump to around 500,000 years ago, and in this gap we have almost nothing. It is extremely exciting to have fossils right in the middle of this gap.
Jean-Jacques Hublin, Collège de France / Max Planck Institute (study coauthor)
Hublin’s comment, from the study team, highlights the chronological importance of the deposit and why a fill in that interval can reshape conversations about lineage splitting and trait emergence.
The dating method anchored the presence of these hominins within an exceptionally precise chronological framework.
Serena Perini, University of Milan (paleomagnetist; study coauthor)
Perini emphasizes the strength of tying the layer to the Matuyama–Brunhes reversal; precise dating reduces ambiguity when aligning fossils with genetic estimates. External commentators note how morphology and context must both inform taxonomic and evolutionary interpretations.
Any hominin fossil from this critical time period makes for an exciting new window into human evolution.
Carrie Mongle, Stony Brook University (anthropologist, not involved in study)
Unconfirmed
- Whether the Moroccan specimens represent a direct ancestor of Neanderthals, Denisovans and Homo sapiens remains unresolved pending additional fossils and analysis.
- The precise taxonomic identity (for example, assignment to Homo antecessor, Homo heidelbergensis, or a regional Homo erectus population) is not confirmed and requires broader comparative study.
- The role of the Thomas Quarry population in later migrations or gene flow events across Africa and Eurasia is currently speculative without genetic data from the specimens.
Bottom line
The Thomas Quarry fossils provide the first securely dated hominin material from a mid-Pleistocene interval in Africa that has long lacked specimens, and the Matuyama–Brunhes age of 773,000 years places them at a critical moment for understanding how major human lineages diverged. Their mosaic anatomy demonstrates that evolutionary change proceeded in a patchwork fashion, with ancestral and derived traits co-occurring within the same population and region.
Although the team does not propose a new species name, the remains will sharpen hypotheses about the identity and geographic distribution of the populations that contributed to Neanderthals, Denisovans and modern humans. Future discoveries, additional comparative morphological work and, if possible, molecular data will be necessary to move from plausible scenarios to confident reconstructions of our deep past.
Sources
- CNN — (news report summarizing the study and interviews with researchers)
- Nature — (peer-reviewed scientific journal; study published in Nature)
- Max Planck Institute for Evolutionary Anthropology — (research institute; affiliations for lead author)
- University of Milan — (academic institution; paleomagnetism coauthor affiliation)