Jebel Irhoud Research Articles

A Late Pleistocene hominin footprint site on the North African coast of Morocco

Footprints represent a relevant vestige providing direct information on the biology, locomotion, and behaviour of the individuals who left them. However, the spatiotemporal distribution of hominin footprints is heterogeneous, particularly in North Africa, where no footprint sites were known before the Holocene. This region is important in the evolution of hominins. It notably includes the earliest currently known Homo sapiens (Jebel Irhoud) and the oldest and richest African Middle Stone Age hominin sites. In this fragmented ichnological record, we report the discovery of 85 human footprints on a Late Pleistocene now indurated beach surface of about 2800 m2 at Larache (Northwest coast of Morocco). The wide range of sizes of the footprints suggests that several individuals from different age groups made the tracks while moving landward and seaward across a semi-dissipative bar-trough sandy beach foreshore. A geological investigation and an optically stimulated luminescence dating of a rock sample extracted from the tracksite places this hominin footprint surface at 90.3 ± 7.6 ka (MIS 5, Late Pleistocene). The Larache footprints are, therefore, the oldest attributed to Homo sapiens in Northern Africa and the Southern Mediterranean.

An Overview of the Benefit of Archaeology to the Study of African History

Every place around the world has a past. Effort has been made to improve the method of historical studies and research in an effort to better understand the past events, culture, people, places, traditions, values etc. The quest to acquire all these knowledge berried in the distant past is critical to academic excellence not just history as a discipline. Archaeology involves surveying, excavation, and eventually analysis of data collected, to learn more about the past. In broad scope, archaeology relies on cross-disciplinary research. Africa has the longest record of human habitation in the world. The first humans emerged 6-7 million years ago, and among the earliest anatomically modern human skulls found so far were discovered at Omo Kibish, Jebel Irhoud, and Florisbad. However, Africa has the larger part of its past unwritten because of lack of writing knowledge, hence, the critical role of archaeology to supplement oral traditions which modern African historians relied heavily on. This research aim to explicitly detail the benefit of archaeology to the study and understanding of African history, it reveals how archaeology could further aid in debunking Eurocentric views of Africa lacking history and also emphasized the role archaeology could play in helping history students understand the past.

The relevance of late MSA mandibles on the emergence of modern morphology in Northern Africa

North Africa is a key area for understanding hominin population movements and the expansion of our species. It is home to the earliest currently known Homo sapiens (Jebel Irhoud) and several late Middle Stone Age (MSA) fossils, notably Kébibat, Contrebandiers 1, Dar-es-Soltane II H5 and El Harhoura. Mostly referred to as “Aterian” they fill a gap in the North African fossil record between Jebel Irhoud and Iberomaurusians. We explore morphological continuity in this region by quantifying mandibular shape using 3D (semi)landmark geometric morphometric methods in a comparative framework of late Early and Middle Pleistocene hominins (n = 15), Neanderthals (n = 27) and H. sapiens (n = 145). We discovered a set of mixed features among late MSA fossils that is in line with an accretion of modern traits through time and an ongoing masticatory gracilization process. In Northern Africa, Aterians display similarities to Iberomaurusians and recent humans in the area as well as to the Tighenif and Thomas Quarry hominins, suggesting a greater time depth for regional continuity than previously assumed. The evidence we lay out for a long-term succession of hominins and humans emphasizes North Africa’s role as source area of the earliest H. sapiens.

Late Middle Pleistocene Harbin cranium represents a new Homo species

Late Middle Pleistocene Harbin cranium represents a new Homo species

How did modern morphology evolve in the human mandible? The relationship between static adult allometry and mandibular variability in Homo sapiens

Key to understanding human origins are early Homo sapiens fossils from Jebel Irhoud, as well as from the early Late Pleistocene sites Tabun, Border Cave, Klasies River Mouth, Skhul, and Qafzeh. While their upper facial shape falls within the recent human range of variation, their mandibles display a mosaic morphology. Here we quantify how mandibular shape covaries with mandible size and how static allometry differs between Neanderthals, early H. sapiens, and modern humans from the Upper Paleolithic/Later Stone Age and Holocene (= later H. sapiens). We use 3D (semi)landmark geometric morphometric methods to visualize allometric trends and to explore how gracilization affects the expression of diagnostic shape features. Early H. sapiens were highly variable in mandible size, exhibiting a unique allometric trajectory that explains aspects of their ‘archaic’ appearance. At the same time, early H. sapiens share a suite of diagnostic features with later H. sapiens that are not related to mandibular sizes, such as an incipient chin and an anteroposteriorly decreasing corpus height. The mandibular morphology, often referred to as ‘modern’, can partly be explained by gracilization owing to size reduction. Despite distinct static allometric shape changes in each group studied, bicondylar and bigonial breadth represent important structural constraints for the expression of shape features in most Middle to Late Pleistocene hominin mandibles.

Earliest African evidence of carcass processing and consumption in cave at 700 ka, Casablanca, Morocco

To date, in Africa, evidence for animal processing and consumption in caves routinely used as living spaces is only documented in the late Middle Pleistocene of the North and South of the continent and postdates the Middle Pleistocene in East Africa. Here we report the earliest evidence in a North-African cave (Grotte des Rhinocéros at Casablanca, Morocco) of cut, percussion and human gnawing marks on faunal remains directly associated with lithic knapping activities in the same space and in a well-documented stratified context. Ages for this Acheulean site are provided by the dating of herbivorous teeth to 690–720 ka and 520–550 ka (lower and upper sets) by combined Electron Spin Resonance (ESR) and U-series techniques. Traces of butchery on gazelle, alcelaphin, and zebra bones demonstrate that hominins had primary access to herbivore carcasses. Hominins brought and consumed meat in the cave, as documented by herbivore bones bearing human tooth marks concentrated in a circumscribed area of the excavation. In Africa, this site provides the earliest evidence for in situ carcass processing and meat-eating in cave, directly associated with lithic production and demonstrates the recurrent use by early Middle Pleistocene hominins of a North African cave site 400 000 years before that by Homo sapiens at Jebel Irhoud (Morocco).

Before the massive modern human dispersal into Eurasia: A 55,000-year-old partial cranium from Manot Cave, Israel

Genetic and archaeological models predict that African modern humans successfully colonized Eurasia between 60,000 and 40,000 years before present (ka), replacing all other forms of hominins. While there is good evidence for the first arrival in Eurasia around 50-45ka, the fossil record is extremely scarce with regard to earlier representatives. A partial calvaria discovered at Manot Cave (Western Galilee, Israel) dated to >55 ka by uranium–thorium dating was recently described. Since then, other findings indicated an early dispersal of modern humans out-of-Africa between 194 and 177ka (Misliya-1) or possibly even earlier at 210ka (Apidima 1), and a quite long existence of Homo sapiens in Africa (Jebel Irhoud, ~300ka). While the faces of these early Homo sapiens appear quite modern, the shape of the braincase seems to lack behind, reaching the modern state only around after 35ka. Here, new data and approaches were applied to the Manot 1 calvaria. The ecto- and endocranial shape analyses based on micro-computed tomography data and a landmark-semilandmark approach using multiple reconstructions of the incomplete calvaria confirm that Manot 1 is unequivocally modern human. Its endocranial shape is markedly different from the earliest known Homo sapiens and close to the Levantine Qafzeh/Skhul assemblage (120-90ka) as well as modern humans, but still shows some deviations from both groups. The absence of other Homo sapiens fossils in the Levant between the Qafzeh/Skhul and Manot populations is not supportive for the hypothesis of a continuous occupation or the local evolution of modern humans. It suggests that Manot 1 represents a population migrating out-of-Africa and reaching the Levantine corridor during warmer and wetter climatic conditions over the Northern Sahara and the Mediterranean. Manot 1 shows that both modern humans and Neanderthals (e.g. Kebara, Amud) contemporaneously inhabited the Levant during the Middle to Upper Paleolithic interface. The endocranial shape of Manot 1 might indicate that this population had not yet fully reached the brainshape of modern humans evident after 35ka.

Reassessment of the Middle Pleistocene human remains from Rabat-Kébibat (Morocco)

The peopling of North Africa and the emergence of the first Homo sapiens is an ongoing debate, recently enriched by the discovery of a new human fossil remain in Jebel Irhoud (Morocco), attributed to a modern human and dated to ca 300 ka. In this context, it seems important to reassess all the human fossil record available in the area, integrating also new discoveries and data in order to precisely understand the dynamic of the peopling of this region. We propose here a reevaluation of the human fossils remains collected by Marçais in the early twentieth century in the Rabat-Kébibat quarry and belonging to the Middle Pleistocene period. The Rabat-Kébibat quarry, situated on the Atlantic littoral some 10km south of Rabat, is known geologically and chronologically since the 1930s. Recently, a Franco-Moroccan team has undertaken new investigation of the coastal region of Rabat with the aim of reconstructing the evolution of landscape of the Moroccan North Atlantic coast from the end of the Middle Pleistocene to the Upper Pleistocene. In this framework, different stratigraphical sequences from several sites has been analyzed and compared. This study has allowed to hypothesize that the human fossil remains from Rabat-Kébibat probably belong to a MIS 7 stratigraphical level.

Which way to turn? Is the Haua Fteah a Levantine site?

AbstractRecent work has shown early modern human occupation at Jebel Irhoud, Morocco, dating as far back as MIS 9 (337–300 Ka). Such early dates double the period in which modern humans were present in North Africa, with implications for several key debates on modern human origins and subsequent spread. Routes across a ‘Green Sahara’ allowed population movement intermittently from sub-Saharan Africa and across the Saharan region in general. This has implications for the debate about the timing and routes of modern human expansion across and out of Africa, but also has the effect of focusing discussion on the archaeological record of sub-Saharan Africa and even Arabia for evidence of human behaviour and adaptations. This may be unfortunate as the record for much of the vast area of sub-Saharan Africa and Arabia is extremely limited and the more detailed record of the Levantine region is overlooked. Work at the Haua Fteah and in its surrounding region (Cyrenaican Libya) provides an opportunity to investigate how far the Palaeolithic record for this part of North Africa is, in fact, a product of trans-Saharan, North African or Levantine, influences. The genetic evidence suggests the process of modern human expansion out of Africa, and just as importantly within Africa itself, was a complex one that may have involved population movements into and out of North Africa from several different directions. A concentration upon the Green Sahara hypothesis may distract current research from this broader picture.

Author Correction: New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens.

In the originally published version of this Letter, the x axis in Fig. 3a should have been: 'PC1: 26%' rather than 'PC1: 46%', and the yaxis should have been: 'PC2: 16%' rather than 'PC2: 29%'. We also noticed an error in the numbering of the fossils from Qafzeh: Qafzeh 27 should be removed, and Qafzeh 26 is actually Qafzeh 25, following Tillier (2014)1 and Schuh et al. (2017)2 and personal communication with B. Vandermeersch and M. D. Garralda. The correct enumeration of Qafzeh samples in the 'Mandibular metric data' section of the Methods is therefore: 'Qafzeh (9, 25)' rather than 'Qafzeh (9, 26, 27)'. Owing to the removal of Qafzeh 27, the convex hull of early modern humans changes slightly in Extended Data Fig. 1c. The sample sizes in Extended Data Fig. 1c should have read: Middle Pleistocene archaic Homo n=19 (instead of 11), Neanderthals n=40 (instead of 41), early modern humans n=12 (instead of 7), and recent modern humans n=46 (instead of 48). In Extended Data Table 2, the mean and standard deviation of corpus height and breadth at mental foramen for early modern humans should have been: x̅=33.15, σ=3.26 for height (rather than x̅=34.23, σ=4.57); and x̅=16.25, σ=1.28 for breadth (rather than x̅=16.04, σ=1.75). Accordingly, n=12 (rather than n= 13) for both breadth and height. These errors have been corrected in the Letter online (the original Extended Data Fig. 1 is shown in Supplementary Information to this Amendment). These changes do not alter any inferences drawn from the data.

Speleothem evidence for the greening of the Sahara and its implications for the early human dispersal out of sub-Saharan Africa

Although there is a consensus that there were wet periods (greening events) in the Sahara in the past, the spatial extent and the timing of these greening events are still in dispute, yet critical to our understanding of the early human dispersal out of Africa. Our U-series dates of speleothems from the Northeastern Sahara (Wadi Sannur cave, Egypt) reveal that the periods of speleothem growth were brief and restricted to the interglacial Marine Isotope Stages MIS 5.5, MIS 7.3, and the early MIS 9 with a remarkable absence of the Holocene deposition of speleothems. These growth periods of Wadi Sannur cave speleothems correspond to periods of high rainfall and spread of vegetation (green Sahara). Distinct low δ18O values of speleothems indicate a distal moisture source that we interpret to be the Atlantic Ocean. These two lines of evidence from the Wadi Sannur speleothems thus suggest that maximal northward shifts in the West African monsoon system occurred during the growth periods of the speleothems, leading to greening of the Sahara, facilitating human migration into Eurasia. The periods of speleothem growth at Wadi Sannur cave are contemporaneous with important archeological events: (1) the earliest occurrence of the Middle Stone Age assemblages and Homo sapiens in North Africa (Jebel Irhoud), suggesting wide spread of greening conditions over the East–West transect of the Sahara, (2) the sharp technological break between the Acheulo-Yabrudian and the Mousterian industries, and (3) the arrival of Homo sapiens in Levant, indicating a key role of the Sahara route in early human dispersal out of Africa.

New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens.

Fossil evidence points to an African origin of Homo sapiens from a group called either H. heidelbergensis or H. rhodesiensis. However, the exact place and time of emergence of H. sapiens remain obscure because the fossil record is scarce and the chronological age of many key specimens remains uncertain. In particular, it is unclear whether the present day 'modern' morphology rapidly emerged approximately 200 thousand years ago (ka) among earlier representatives of H. sapiens or evolved gradually over the last 400 thousand years. Here we report newly discovered human fossils from Jebel Irhoud, Morocco, and interpret the affinities of the hominins from this site with other archaic and recent human groups. We identified a mosaic of features including facial, mandibular and dental morphology that aligns the Jebel Irhoud material with early or recent anatomically modern humans and more primitive neurocranial and endocranial morphology. In combination with an age of 315 ± 34 thousand years (as determined by thermoluminescence dating), this evidence makes Jebel Irhoud the oldest and richest African Middle Stone Age hominin site that documents early stages of the H. sapiens clade in which key features of modern morphology were established. Furthermore, it shows that the evolutionary processes behind the emergence of H. sapiens involved the whole African continent.

The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age.

The timing and location of the emergence of our species and of associated behavioural changes are crucial for our understanding of human evolution. The earliest fossil attributed to a modern form of Homo sapiens comes from eastern Africa and is approximately 195 thousand years old, therefore the emergence of modern human biology is commonly placed at around 200 thousand years ago. The earliest Middle Stone Age assemblages come from eastern and southern Africa but date much earlier. Here we report the ages, determined by thermoluminescence dating, of fire-heated flint artefacts obtained from new excavations at the Middle Stone Age site of Jebel Irhoud, Morocco, which are directly associated with newly discovered remains of H. sapiens. A weighted average age places these Middle Stone Age artefacts and fossils at 315 ± 34 thousand years ago. Support is obtained through the recalculated uranium series with electron spin resonance date of 286 ± 32 thousand years ago for a tooth from the Irhoud 3 hominin mandible. These ages are also consistent with the faunal and microfaunal assemblages and almost double the previous age estimates for the lower part of the deposits. The north African site of Jebel Irhoud contains one of the earliest directly dated Middle Stone Age assemblages, and its associated human remains are the oldest reported for H. sapiens. The emergence of our species and of the Middle Stone Age appear to be close in time, and these data suggest a larger scale, potentially pan-African, origin for both.

The origin and evolution of Homo sapiens.

If we restrict the use of Homo sapiens in the fossil record to specimens which share a significant number of derived features in the skeleton with extant H. sapiens, the origin of our species would be placed in the African late middle Pleistocene, based on fossils such as Omo Kibish 1, Herto 1 and 2, and the Levantine material from Skhul and Qafzeh. However, genetic data suggest that we and our sister species Homo neanderthalensis shared a last common ancestor in the middle Pleistocene approximately 400-700 ka, which is at least 200 000 years earlier than the species origin indicated from the fossils already mentioned. Thus, it is likely that the African fossil record will document early members of the sapiens lineage showing only some of the derived features of late members of the lineage. On that basis, I argue that human fossils such as those from Jebel Irhoud, Florisbad, Eliye Springs and Omo Kibish 2 do represent early members of the species, but variation across the African later middle Pleistocene/early Middle Stone Age fossils shows that there was not a simple linear progression towards later sapiens morphology, and there was chronological overlap between different 'archaic' and 'modern' morphs. Even in the late Pleistocene within and outside Africa, we find H. sapiens specimens which are clearly outside the range of Holocene members of the species, showing the complexity of recent human evolution. The impact on species recognition of late Pleistocene gene flow between the lineages of modern humans, Neanderthals and Denisovans is also discussed, and finally, I reconsider the nature of the middle Pleistocene ancestor of these lineages, based on recent morphological and genetic data.This article is part of the themed issue 'Major transitions in human evolution'.

Geometric variation of the frontal squama in the genus homo: Frontal bulging and the origin of modern human morphology

The majority of studies of frontal bone morphology in paleoanthropology have analyzed the frontal squama and the browridge as a single unit, mixing information from different functional elements. Taking into account that the bulging of the frontal bone is often described as a species-specific trait of Homo sapiens, in this article we analyze variation in the midsagittal profile of the genus Homo, focusing on the frontal squama alone, using landmark-based superimpositions and principal components analysis. Our results demonstrate that anatomically modern humans are definitely separated from extinct human taxa on the basis of frontal bulging. However, there is minor overlap among these groups, indicating that it is necessary to exercise caution when using this trait alone to make taxonomic inferences on individual specimens. Early modern humans do not show differences with recent modern humans, and "transitional" individuals such as Jebel Irhoud 1, Maba, and Florisbad, show modern-like frontal squama morphology. The bulging of the frontal squama in modern humans may represent a structural consequence of more general cranial changes, or it could be a response to changes in the morphology of the underlying prefrontal brain elements. A subtle difference between Neandertals and the Afro-European Middle Pleistocene Homo sample is associated with flattening at bregma in the former group, a result that merits further investigation.

Growing up slowly 160,000 years ago

For centuries, it has been recognized that, in the absence of a birth certificate, the best way to estimate the chronological age of a growing child is from his/her teeth. Some of the earliest studies of dental development were carried out to document the variability of tooth eruption with respect to chronological age at a time when, for example in England, the Factory Act of 1833 made it legal for children aged 9–13 years to work a 9-h day in textile mills. Data for dental eruption in 1837 showed that between their eighth and ninth birthdays, 524 of 530 children had both lower incisors erupted (1). Since that time, the trend to grow to greater heights and weights has increased dramatically in line with better nutritional and social conditions. However, over the same period, there has been little change in the timing of tooth eruption (2). In this issue of PNAS, Smith et al. (3) use novel techniques to estimate the chronological age of an ancient modern human from Jebel Irhoud, Morocco, dated to 160,000 years before the present (ybp). They show that the age of lower incisor tooth eruption was much the same then as it is today.

Earliest evidence of modern human life history in North African early Homo sapiens.

Recent developmental studies demonstrate that early fossil hominins possessed shorter growth periods than living humans, implying disparate life histories. Analyses of incremental features in teeth provide an accurate means of assessing the age at death of developing dentitions, facilitating direct comparisons with fossil and modern humans. It is currently unknown when and where the prolonged modern human developmental condition originated. Here, an application of x-ray synchrotron microtomography reveals that an early Homo sapiens juvenile from Morocco dated at 160,000 years before present displays an equivalent degree of tooth development to modern European children at the same age. Crown formation times in the juvenile's macrodont dentition are higher than modern human mean values, whereas root development is accelerated relative to modern humans but is less than living apes and some fossil hominins. The juvenile from Jebel Irhoud is currently the oldest-known member of Homo with a developmental pattern (degree of eruption, developmental stage, and crown formation time) that is more similar to modern H. sapiens than to earlier members of Homo. This study also underscores the continuing importance of North Africa for understanding the origins of human anatomical and behavioral modernity. Corresponding biological and cultural changes may have appeared relatively late in the course of human evolution.

Les Anoures (Amphibiens) du pléistocène inférieur (« Villafranchien å) du Jebel Irhoud (carrir̀e « Ocre å), Maroc

Anurans (Amphibians) from the Late Pleistocene (“Villafranchian”) of Jebel Irhoud (“Ocre” quarry), Morocco. The Villafranchian anurans of Jebel Irhoud (“Ocre” quarry) Morocco, belong to the Discoglossidae ( Baleaphryne), Bufonidae ( Bufo cf. B. viridis, Bufo cf. B. regularis) and Ranidae ( Rana sp.). The presence of Pelodytidae ( Pelodytes) in this site is possible but not ascertained. The genus Baleaphryne is reported for the first time in Africa. Likewise, Pelodytes, if this identification proves correct, would be the first one ever found in Africa.

Hominid evolution in northwest Africa and the question of the north African “Neanderthaloids”

AbstractThe North African evidence bearing on hominid evolution is summarized and reviewed in relation to its industrial associations and apparent chronological order. Three tacit suppositions of the past and their effects on taxonomy and thinking in evolutionary anthropology are examined, namely the concepts of a single and unique origin of Man, of the inherent and essential, distinction between physical and spiritual Man, and of physical resemblance as absolute proof of relationship. The consequent confusion and looseness of application which have characterized hominid taxonomy, especially concerning the term Neanderthal and its derivatives, are examined and discussed primarily in relation to the so‐called Neanderthals of northern Africa.It is suggested that the Atlanthropus remains may represent not one but two hominid varieties. Further it is argued that none of the North African remains are demonstrably related to the European Neanderthals and that some at least of them seem clearly unrelated. In conclusion it is suggested that the hominid remains from Ternifine, the Littorina Cave (Casablanca), Témara, Rabat, Jebel Irhoud and Tangier may represent links in a North African chain of hominid evolution which developed locally and remained independent of all external influence during the period covered by those specimens.