Neanderthal timeline 2: Gibraltar 2.

Discovered in 1848 by Captain Edmund Flint, or so the story goes. Flint, a British Royal Navy officer was overseeing the extraction of limestone to reinforce and rebuild the military fortress’s fortifications.  The renovation of the stone walls had begun in 1841, after General Sir John Thomas Jones of the Royal Engineers conducted a study of Gibraltar's defenses and recommended improvements.

The stone for the construction of Jones’ "retired batteries" was got, by the use of gunpowder in quarries such as Forbes’ quarry. Why Capt. Flint, a naval officer was overseeing the work and who the workers were, is unknown.

A local, likely apocryphal story has it that, consequent to blasting Flint retired to a campaign chair in the shade, while local Gibraltar men set about shifting the stone. Some while later he was disturbed by a shout, put up by the workers: removal of blocks had revealed a previously hidden cave without any apparent external openings. The workers had looked in and apparently seen bones. This is what caused them to send up alarums. Flint it seems, availed himself of a skull found in the cave.

Whatever the circumstances of the find Capt. Flint, some time later, presented the skull to the Gibraltar Scientific Society. It went to the garrison library, where it languished, forgotten, with the label "an ancient human, died before the universal flood". After Charles Darwin published On the Origin of Species by Means of Natural Selection, in 1859, a renewed interest in the fossil human remains led to the skull being brought out of obscurity and presented at a meeting in the British Association for the Advancement of Science in 1864. From there it went to the Royal College of Surgeons. It is now housed in the Natural History Museum in London.

Gibraltar 1 cranium, a female and probably between 60,000 to 120,000 years old. Image credit: Pavid (2019).

At least the part of the story about the skull being found in a previously sealed cave was current among the learned men of the time. This is proved by the quip of George Busk (1864): “..in many respects, it [Gibraltar 1] is of infinitely higher value than that much-disputed relic, Neanderthal 1… [It] adds immensely to the scientific value of the Neanderthal specimen, if only as showing that the latter does not represent, as many have hitherto supposed, a mere individual peculiarity, but that it may have been characteristic of a race extending from the Rhine to the Pillars of Hercules; for, whatever may have been the case on the banks of the Dussel, even Professor Mayer will hardly suppose that a rickety Cossack engaged in the campaign of 1814 had crept into a sealed fissure in the Rock of Gibraltar.” Here Busk is referring to the theory of Mayer that Neanderthal 1 was a rickety Cossack. Mayer’s published views are well summarized by Schrenk and Müller (2010): “He confirmed the Neanderthaler's "rickety" changes in bone development... Mayer argued, among other things, that the thigh and pelvic bones of the Neanderthal man were shaped like those of someone who had spent all his life on horseback. The broken right arm of the individual had only healed very badly and resulting permanent worry lines due to the pain were the reason for the distinguished brow ridges. The skeleton was, he speculated, that of a mounted Russian Cossack, who had roamed the region in 1813/14 during the turmoils of the wars of liberation from Napoleon."

While Busk was humorously dismissive of Mayer’s interpretation of the other Neanderthal skull and remains, obviously something about the circumstances of the discovery, of Gibraltar 1, didn’t sit well with him. Undoubtedly, it was the condition of the Gibraltar 1 skull, with its sandy lime concretions that caused his disquiet. Busk, therefore determined to visit the find spot himself. Menez (2018), explains the circumstances of his subsequent exploration at Gibraltar: “Busk had planned to visit Gibraltar, noting in The Reader (Busk 1864a) that the purpose, with the full support of the Governor, Falconer and Busk (1865), was “to examine on the spot the conditions under which the different classes of fossils occur in the caverns &c”. The trip would wait, however, until after the Bath [BAAS] meeting, perhaps becoming even more important than hitherto after it became apparent that information related to the skull, which had engendered interesting debate in Bath, was scarce (Busk 1864b), Busk noting that: “The only information which we have been furnished respecting the situation in which it was found, is to the effect that it was dug up in the course of some excavations being made in what is termed ‘Forbes’ Barrier’… The exact locality, however, does not appear to rest upon any very certain evidence, and it may perhaps turn out that this interesting relic was derived from some other situation in the rock.” Busk, accompanied by Hugh Falconer and the British physician and travel writer Henry Holland, arrived in Gibraltar aboard the Poonah on 24 September 1864.” Busk, Falconer and Lieutenant Alexander Burton-Brown, thereafter visited Forbes’ Quarry. Brown (1867) later reported: 

“..in October, 1864, examining with Professor Busk the slope of the old quarry of Forbes [sic] we found the  matrix in which we believed the skull had been imbedded, which was a raised beach of about 100 ft. above sea level, and which was seen everywhere to be cropping out of the limestone slope, the inner portion of the beach being covered with broken pieces of calcareous rock, and the outer being broken off, disjointed masses being carried down by the crumbling masses of limestone; many subsequent visits confirm me in the opinion of this being the veritable matrix.”

Busk (1865) reporting his observations at Forbes’ Quarry said “…from the matrix with which it [the skull] was thickly covered, and which contained a very large proportion of coarse rolled siliceous sea-sand, similar to that which is blown up in such large quantities against the north-eastern end of the rock, it was apparent that it had been lodged in the superficial part of the talus in which the quarry is worked.”

Top: Busk’s photographs of the skull before removal of the matrix. Bottom: Busk’s photographs of the skull following partial removal of the matrix. Bottom: the skull today. Picture credit: Archives of the Royal College of Surgeons.

In 1865, mid-way through his description of Gibratar 1, Busk received an urgent message to attend to his close friend Hugh Falconer. Falconer had started to feel feverish on the 19^th of January. According, to, Murchison (1868) “the attack developed into acute rheumatism, complicated with disease of the heart and lungs, which proved fatal.” Busk was at his side as he died. Without Falconer, Busk apparently could not continue, and he never finished his analysis of Gibraltar 1.

Within a year of Busk’s announcement that the Forbes skull was an object of immense scientific importance, it had retreated back into the shadows once again. The skull had been found but then quickly lost, tucked into a back room of Busk’s Royal College of Surgeons, collecting dust.

Other scientists visited the site of Forbes’ quarry in latter, years to try to further clarify the exact find spot.  Results were varied, and somewhat confusing.

Samuel William Turner, Surgeon to the Colonial Hospital in Gibraltar, it seems was encouraged, by Sir Arthur Keith, to seek what information he could on the Forbes Quarry site. Turner (1910) reported back: “the sloping talus which abutts on the perpendicular line above of the north face of the Rock at this point forms with the limestone the quarry referred to, and there is a distinct line of demarcation between the limestone and the conglomerate of the talus.” He then conjectured a possibility that has been perpetuated in the published literature ever since, describing that there was a small cave at the juncture between the conglomerate and the limestone, Turner surmised that “possibly the skull may have been found in this cave”. His description of the cave: “40 ft long, 8 wide” and requiring him to “stoop somewhat”, it showed no trace of osseous remains. Turner (1910), wrote again to Keith on 28 April 1910,  informing him that “I fear we shall not be able to definitely locate to within a few yards the spot where the skull was found, or to say whether it was found embedded in the conglomerate of the talus at Forbe’s [sic] Quarry, or lying on the floor of the cave which exists in that quarry.”

Duckworth (1911), also visited the quarry in 1910, with William Turner, Colonel Kenyon, and others. His comments have been cited by many authors, such as Menez (2018): “the skull was discovered in the brecciated talus is therefore quite possible.” However, he also added the he “not understand why Dr Busk should have considered that it [the skull] was derived from the superficial part.” and “For the talus is, in fact, exposed vertically throughout a very wide extent.”

While quoting Duckworth precisely, some details were left out, which, add more context. I’ll come back to that later.

Duckworth (1910), also contemplated that the cave might be a possibility. Having assessed the area of Forbes’ Quarry to be composed of “more solid rock”, (compared to the brecciated talus), it would be “excluded at once, were it not that just at this spot it contains a cave.” He explored the cave from 13 to 17 September, but found it contained “nothing save the very earliest and seemingly marine deposits covered with stalagmite.”

The answer to his query as to why Busk had opined that the Gibraltar 1 skull came from the “superficial” part of the talus had been staring him in the face as he crossed the floor of the quarry: the lime kiln. Living in the Peak District, as I do, I have often observed that those labourers of the 19^th century, when fetching limestone to ‘burn’ in their kilns, naturally start with the material closest to the kiln. In the case of Forbes’ Quarry, the brecciated slope must have, been seen, as an excellent source limestone for produced quicklime (calcium oxide). Therefore, in the 50 years, between Busk and Falconer’s visit to the quarry, the local lime burners had obviously worked the slope of Busk and Falconer back into the vertical outcrop of Duckworth. Whatever the position of the skull in the talus, the point was made moot as on Christmas Day 1910, an absolutely massive, landslip almost filled the quarry entirely.

Duckworth’s (1911) sketch of the Forbes’ Quarry Cave. Duckwoth’s comments, verbatim, form the original paper: “The actual appearance of the surface exposed by the workings in this quarry can be described more clearly with the aid of the sketch (Plate XL, Fig. 1), to which reference will now be made. The face that has been worked must have had much the same character throughout and it is quite peculiar, for the quarry lies exactly at the zone of union of the solid rock, shown in Plate XL, Fig. 1, to the right, with an extraordinary mass of consolidated debris known as the "brecciated talus."

That the skull was discovered in the brecciated talus is therefore quite possible, but I do not understand why Dr. Busk should have considered that it was derived from the superficial part. For the talus is, in fact, exposed vertically throughout a very wide extent.” This drawing makes it clear that the brecciated talus, was to the left of the cave, and that the removal of it, presumably for lime burning, did indeed remove a great deal of it, with the workings moving right to left. A modern photograph shows the scene today:

Menez (2018), photograph of the location of Forbes’ Quarry Cave. Remnants of brecciated talus can still be seen on the left of the pillbox and solid rock to right. This, seems to me, to point to an origin for Gibraltar 1, higher up the slope, in a cave which, has been eroded away. Original caption reads: “Figure 4. The location of the cave at Forbes’ Quarry in 2016 (author’s photograph). The cave is still accessible from within the Second World War pillbox.” 

Breuil (1922) the area three times over the next decade (1911, 1917 and 1919) and commented on Forbes’ Quarry and examined  “the foot of the slopes formed by the rocky rubbish of Forbes Quarry.” He noted that the breccia was no longer in situ “on account of a gigantic landslide”. He also noted that the “old marine rock-shelter of Forbes Quarry [the cave] was of no interest, and had never contained deposits other than marine gravels and a layer of stalagmite and clay, with the bones of very small mammals.”

On his perambulations, around the area, Breuil did notice that an intact talus slope fronted Devil’s Tower Cave nearby. He was unable to excavate this himself, and recommended it to his student, Dorothy Garrod, as a likely place to seek further Neanderthal remains. 

Now I must step back many years to look at how archaeologists classified the Gibraltar 1 skull. The first to give a detailed description was Broca (1868). He gives some measurements and makes a few comparisons, which while not a formal diagnosis, highlighted the differences between it and save but one other, fossil skulls excavated up to 1868.

His description reads thus:

“3° Another prehistoric skull. The last two photographs sent to us by Mr. Busk represent the face and profile of an extremely curious skull, which also comes from the vicinity of Gibraltar, but which appears much older than the previous ones [from Genista cave]. The date of this skull is also undetermined! It was not found in caves, but in the surrounding soil. It was buried in a very compact, very adherent matrix, from which we could only release with the greatest difficulty.

A large part of the vault, between the bregma and the lambda, is absent. What remains of the vault presents a slight degree of asymmetry which seems to be the consequence of a posthumous deformation. I cannot give geological information on the ground from which this skull was extracted. According, to Mr. Busk's communication to the Norwich Congress, no characteristic fossils were found there; but everything indicates, moreover, that this site is extremely old, and the skull itself presents characteristics of inferiority, which fully confirm this view, and to which Professor Huxley has drawn the attention of members of Congress.

The absence of part of the vault and the fragments of gangue which still adhere to several points do not allow the diameters to be rigorously measured in order to determine the cephalic index, but it is evident that this skull is very dolichocephalic. It is not very bulky; but its walls are very thick; around the perimeter, the thickness of the parietals amounts to 9 and a half millimeters. The superciliary arches form a considerable projection on the profile; the forehead is small and very elusive.

The face is broad and prognathous, the opening of the anterior nostrils is very wide, the eye sockets are enormous and almost rounded in shape. Their width is 44 millimeters, their height 39, their depth 51. The width of 44 millimeters is the largest I have found so far on a human skull; it is exactly that of the orbits of the old man of Les Eyzies, but in the latter case the enormous transverse development of the orbital openings coincided with an excessive reduction of the vertical diameter (27 millimeters), while on the Gibraltar skull the height of the orbit is on the contrary exaggerated. As a result, despite the extreme width of the orbit, the orbital index rises to 68.83, an enormous figure, nearly 4 percent higher than the maximum that I have encountered so far in man. The interorbital space is, moreover, very wide, 23 millimeters below and much larger above.

It follows that the transverse development of the upper part of the face is very great. On the front photograph, we do not see the temporal region, entirely masked by the outer edges of the eye sockets; the external orbital process forms a considerable protrusion, above which the forehead sharply narrows. This forehead is also extremely low, and it is so small in all its dimensions, especially when compared to the face, that it resembles that of apes. Professor Huxley has pointed out the simian shape of the dental arch, which tapers noticeably behind, like a horseshoe. The Company is already aware of the importance of this character, to which, for several years now, Mr. Alix has drawn its attention. Another simian character that Mr. Huxley insisted on is the absence of the canine fossa, which is replaced by a convex surface! Mr. Huxley has so far not seen this conformation on any other human skull, and I believe it can be said that it is not found on none of the skulls in our museum.” 

The next scientist to analyse the Gibraltar 1 skull was Sollas (1908). His work built on that by Huxley (1863) and more especially Schwalbe (1890; 1901a; 1901b; 1904; 1906). The extremely detailed work discusses the problems of measuring skulls accurately including that of establishing a baseline from which to measure and what equipment to use. Sollas measures, computes and compares many lengths, radii and angles of curvature, with reference to a collection of Australian skulls, Neanderthal 1, the Krapina remains, the skulls from Spy, more recent humans and certain great apes. In short the work, running to 60 pages, with copious illustrations and tables of data is a tour de force, the thoroughness of which, many modern papers do not attain.

Sollas comments: “One of the most important, as it is certainly one of the most striking, peculiarities of the Neandertal calotte is the frontal torus, the confluent supra-orbital tori; this is distinguished not merely by its magnitude, though this is excessive, but still more, as Schwalbe points out, by the continuous and uniform character which it maintains throughout its whole extent. In the skulls of Australian natives two regions may usually, though not always, be distinguished in each supra-orbital torus, a more or less shallow groove which takes an oblique course, separating an

outer temporal from a more median supra-ciliary region; in the Neandertal group this groove is almost, if not entirely, effaced.” Sollas goes on to conclude: “Briefly summarising our results, we may remark that the skull of the Neandertal race possesses many features in common with certain flattened skulls which are met with among tribes inhabiting the southern part of Australia ; it differs from them in breadth, being markedly broader, in the characters of the glabellar region, and in thickness. The face of the Neandertal race on the other hand is peculiar. The large round, widely open orbits, the projecting broad nose, the retreating cheek bones, the absence of any depression beneath the orbits, the long face, and the low degree of prognathism distinguish it in the clearest manner from the Australian. “

While Sollas (1908), does not address the thorny issue of nomenclature, he has established two very clear points:

1. Gibraltar 1. Belongs to the ‘Neanderthal race’, since referred to Homo neanderthalensis.

2. More importantly, Sollas has established a system of measurement and comparison for human skulls and Neanderthals in particular.

Palate of Gibraltar 1 skull from Sollas (1908). Original caption reads: Fig. 24. – Outline of the palate of the Gibraltar skull, drawn with an orthopter. ( x 2/3.) 

One last point regarding the actual circumstances of the discovery of Gibraltar 1 is given in Menez (2018): “It may be that an old lady who lived in the small fishing village of Catalan Bay, very near Forbes’ Quarry, was the last living person with first hand knowledge of the skull’s discovery. In his letter to Sir Arthur Keith of 28 April 1910, Samuel William Turner [Turner 1910], reported that: Today I drove round the Rock to Catalan Bay on the Eastern Side to interview an old woman of 84 who was said to know something about the finding of this skull, but I found the old lady almost in her dotage, and could not get reliable facts from her. The lady would have been 22 years old in 1848, and 38 during Busk and Falconer’s visit in 1864. Had she been known to them, we might have a much fuller history of the Gibraltar Skull.”

The information, or rarther lack of it, that Turner gained from the old lady of Catalan Bay, perhaps relates to the apocryphal story I presented at the beginning of this piece? Whatever the true circumstances of the discovery of the Gibraltar 1 skull were, it is almost certain that we will never know.

 

References

Broca, P. (1869) Remarques sur les ossements des cavernes de Gibraltar. In: Bulletins de la Société d'anthropologie de Paris, II° Série. Tome 4. pp. 146-158;

Brown, A. (1867) On the geology of Gibraltar, with especial reference to the recently explored caves and bone breccia. Proceedings of the Royal Artillery Institution, Woolwich 5: 295–304.

Busk, G. (1864a) Pithecoid priscan Man from Gibraltar. The Reader (London) 4 (23 July): 109–110.

Busk, G. (1864b) Ancient human cranium from Gibraltar. The Bath chronicle. Special daily edition September 22 1864: p. 3.

Duckworth, W. L. H. (1911). Cave exploration at Gibraltar in September, 1910. Journal of the Royal Anthropological Institute of Great Britain and Ireland 41: 350–380.

Huxley T. H. (1863). On Some Fossil Remains of Man, in Evidence as to Man's place in nature. Williams & Norgate, London.

Murchison, C (1868). Hugh Falconer, biographical sketch in Falconer Palaeontological Memoirs and Notes of the Late Hugh Falconer, 1868.

London: Spottiswoode and Co; 1868:xlix.

Mayer, F. J. C. (1864a).  Ueber die fossilen Ueberreste eines menschlichen Schädels und Skeletes in einer Felsenhöhle des Düssel- oder Neander-Thales. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. (Müller's Archiv), Heft 1, 1864, S. 1–26.

Mayer, F. J. C. (1864b). Zur Frage über das Alter und die Abstammung des Menschengeschlechtes. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. (Müller's Archiv), 1864, S. 696–728

Menez, A. (2018). The Gibraltar Skull: early history, 1848–1868. Archives of natural history, 45(1), pp.92-110.

Pavid, K. (2019). A new look at the Gibraltar Neanderthals. NHM at: https://www.nhm.ac.uk/discover/news/2019/july/a-new-look-at-the-gibraltar-neanderthals.html accessed 21/08/2021

Schrenk, F. and Müller, S. (2010). Die Neandertaler C. H. Beck München.

Schwalbe, G. (1890). Studien iiber Pithecanthropus erectus,” ‘Zeitschr. f. Morph, u. Anthropol.,’ v.1,

pp. 16-240.

Schwalbe, G. (1901a). Der Neandertalschiidel,” ‘Bonner Jahrbiicher,’ part 106.

Schwalbe, G. (1901b). Uber die specifischen Merkmale des Neandertalschadels,” ‘ Verhandlungen der anatom. Gesellsch.’ 15 Versammlung in Bonn, pp. 44-61.

Schwalbe, G. (1904). Die Vorgesehichte des Menschen, Braunschweig.

Schwalbe, G.A. (1906). Studien zur Vorgeschichte des Menschen (Vol. 1) p. 154 E. Nägele.

Sollas, W.J., 1908. VII. On the cranial and facial characters of the neandertal race. Philosophical Transactions of the Royal Society of London. Series B, Containing Papers of a Biological Character, 199(251-261), pp.281-339.

Turner, S. W. (1910). Letters to Sir Arthur Keith, Archive of the Royal College of Surgeons of England, London: Folder KL II MS0018/1/16/1–19. Now held at the Natural History Museum

The Gortnacrannagh Idol

A carved wooden statue was unearthed by a team from the Archaeological Management Solutions who were carrying out an archaeological survey of the route of the proposed N5 Ballaghaderreen to Scramoge Road Project. The Gortnacrannagh Idol as it is being called, was C13 dated to ca. 350 AD. Only a dozen such idols have been found in Ireland and at more than two and a half metres, the Gortnacrannagh Idol is the largest to date.

The idol during excavation, from Roscommon County Council (2021).

Looking at the face of an Iron Age god, post cleaning, from Murphy (2021). Original caption reads: Wood Specialist, Cathy Moore inspecting the Gortnacrannagh Idol. Only a dozen such idols have been found in Ireland and at more than two and a half metres, the Gortnacrannagh Idol is the largest to date.

Some details are given by Rathcroghan Visitor Centre website (2021):

“The discovery of a wooden pagan idol just 6km northeast of Rathcroghan is cause for great excitement here at Rathcroghan Visitor Centre. The wooden idol, created over 1600 years ago, reveals more of this pre-Christian, iron Age landscape and of the people that made Roscommon their home. Discovered at Gortnacrannagh during archaeological investigation by Archaeological Management Solutions (AMS) in advance of the N5 Ballaghaderreen to Scramoge Road Project, the idol current resides in Universuty College Dublin, where conservator Susannah Kelly is undertaking a three-year process to preserve the ancient object. Excitingly for Rathcroghan Visitor Centre, a full size replica, created to further study this unique find, will soon go on permanent display here in our museum. This will be of great value in telling the story of this fascinating ancient landscape.

Created from a split oak trunk the Gortnacrannah Idol has a small human-shaped head at one end and a series of horizontal notches carved along its body and is thought to have been created in the image of a pagan deity. Discovered in a waterlogged site, AMS archaeologist Dr Eve Campbell, who directed the excavation of the site commented “Our ancestors saw wetlands as mystical places where they could connect with their gods and their Otherworld. The discovery animal bone alongside a ritual dagger suggests that animal sacrifice was carried out at the site and the idol is likely to have been part of these ceremonies.” Roscommon County Council Resident Archaeologist Deidre McCarthy commented “Road projects such as the N5 provide significant opportunity for the investigation of our archaeological heritage. Gortnacrannah is an excellent example. Were it not for the road, we would never have known about this extraordinary site.”

Whilst Campbell’s interpretation of the meaning of the Gortnacrannah Idol is certainly lyrical, I think it is a big stretch to say that “Our ancestors saw wetlands as mystical places where they could connect with their gods and their Otherworld.” Passing off one’s own ideologies as those of, in this case, Iron Age people is fraught with difficulties as these ideas, current in anthropology and to some extent archaeology have no basis in evidence. Put simply, they are just modern ideas dressed up as fact. As McCall and Simmons (1969), say: “Only a person immersed in a culture has the possibility of understanding it deeply.”

A more prosaic, and wider explanation of the possible meanings of these wooden idols was related to Gershon (2021): “The lower ends of several figures were also worked to a point suggesting that they may once have stood upright,” says Cathy Moore, a specialist in wooden artifacts, in the statement. “Their meaning is open to interpretation, but they may have marked special places in the landscape, have represented particular individuals or deities or perhaps have functioned as wooden bog bodies, sacrificed in lieu of humans.”

The face of God? A line drawing of the upper part of the Gortnacrannah Idol from AMS (2021).

Line drawings of the upper and lower sections of the idol as recovered. Anterior and posterior views. AMS (2021).

Virtual reconstruction of the idol, from AMS (2021).

I look forward, with great anticipation, to the undoubted plethora of papers this discovery should unleash in the next few years.

SEE ALSO: The Dagenham Idol (here) 

References

AMS (2021)/ The Gortnacrannah Idol in more detail, at: https://m.facebook.com/AMSarchaeology/ accessed 20/08/2021

Gershon, L. (2021). Eight-Foot-Tall, 1,600-Year-Old Statue of Pagan Deity Found in Ireland. Smithsonian magazine at: https://www.smithsonianmag.com/smart-news/1600-year-old-wooden-idol-found-ireland-180978453/#:~:text=Researchers%20have%20recovered%20an%20eight,of%20a%20road%20construction%20project. Accessed 20/08/2021

McCall, G. J. and J. L. Simmons (1969). Issues in Participant Observation: A Text and Reader. Chicago: Addison-Wesley

Murphy, G. (2021). Archaeologists uncover 1,600-year-old idol in Roscommon bog. Irish Examiner, at: https://www.irishexaminer.com/news/arid-40358522.html accessed 20/08/2021

Rathcroghan Visitor Centre (2021). Gortnacrannah Idol, at: https://m.facebook.com/story.php?story_fbid=10158742705246378&id=130956586377&_ft_=top_level_post_id.10158742705246378%3Acontent_owner_id_new.130956586377%3Aphoto_attachments_list.%5B10158742694086378%2C10158742694311378%2C10158742694676378%2C10158742695031378%5D%3Astory_location.4%3Astory_attachment_style.album&__tn__=%2C%3B accessed 20/08/2021

Roscommon County Council (2021) At: https://m.facebook.com/pg/RoscommonCountyCouncil/photos/ accessed 20/08/2021

 

Further reading

Archaeological Management Solutions (2021). Through Bog & Meadow: The Archaeology of the N5 Road, County Roscommon. At: https://www.arcgis.com/apps/MapJournal/index.html?appid=e45bd5c54fa442bb8a6236335d13b5c8 accessed 20/08/2021

Neanderthal timeline 1: 1829 Engis 2.

The Engis 2 partial cranium was discovered in 1829 by the Dutch physician and naturalist Philippe-Charles Schmerling in the lower of the two Awirs Caves. As Schmerling approached the caves over the Plateau des Fagne, from the village of Engis, he naturally christened them the Grottes d'Engis.

The Awirs valley today, the location of the the Engis 2 cave is not shown as it collapsed in 1993. Photo credit 27 Crags (2017)

These have since become known as the Grottes d'Engis or Schmerling Caves. Schmerling himself, named the caves for Engis because he accessed them from the Plateau des Fagnes, which is in the Engis commune, above the cavities. Schmerling (1833-34) gives a detailed, first-hand account:

From his section II Engis Caves: “Three quarters of a league northwest of Chokier is the place known as the Awirs, located north behind the village Engis. Vis-à-vis a former exploitation of aluminous shale, is a very steep limestone hill, filled with crevices and openings, two of which are on the upper part of this perpendicular cliff; but we see them without being able to reach them from this side. We were therefore obliged to take a means of examining these cavities more closely. Using a rope, attached above to a tree, we were able to slide obliquely towards the foot of a first opening. A small path stretches out at some distance, formed by the rock which advances enough to be walked along. Grass and shrubs have multiplied spontaneously on the sterile rock: they hide in some places the precipice that one has in front of you.

The first cavity is 5 meters wide and 6 high at the entrance the total depth of this cavity is 17 meters: towards the end the vault is lowered more and more. The bottom, in the posterior part, is little covered with earth; a small gallery exists on the right, and it is parallel to the main opening. The bone earth, which presented the same characteristics as that of the other caves, was very abundant on the interior part, where it was 2 meters thick; but towards the posterior part, and in the small side gallery, there were few.

The treasures collected in this cave are: An incisor tooth, a dorsal vertebra and a male phalanx, some remains of bears, hyenas, horses, and ruminants; several flint sizes in triangular shape. By clinging to the walls of the rock, we descend from this first opening to a second, after having passed over a point of the rock, along a small path, 17 meters long. The entrance to this cave is 5 meters high and 4 meters wide; like the previous one, it has a view of the North. It is located one meter below the level of the first; near the beginning of the school year are many shrubs which have grown naturally in the bone earth. The depth of the first chamber, which is the main one, is 12 meters, over a height of 5 and a width of 4m near the entrance is a singular separation, formed by the limestone which passes in a straight line; in this place the cave is cut in two, in the form of an arcade. At the end of this room there is a not very wide gallery which descends to the left, so that it describes a semi-circle, always lowering itself; it is filled with earth containing bones. Soon we find ourselves stopped by the little space offered by this corridor, which ends with a small opening in which we cannot enter. On the left side of the main opening there is a second gallery, which is difficult to reach because of the very slippery stalactites which are at the height of a meter and a half. After crossing this vertical entrance, you find yourself on the limestone bench which goes almost parallel to the entrance. We see on the right an opening which leads in the opposite direction into a small gallery, the floor of which rises towards the south, and at the top of which is a small chamber whose bed was strewn with bones. In addition to the stalactites which are in this cave, one meets in the principal chamber a bony breccia; it is placed near the gallery which is at the back; we will speak of it in more detail in the description of human bones.

The bones of this cave were in general very dry, having the same characters as that of the other localities; it had on the rising, a thickness of two meters and a half, and contained bones and stones rounded and angular throughout its height; it covered in the lower part a clayey ground more or less compact, resting on the bottom formed by the rock, which is everywhere very uneven.

The bones coming from this cave have, in general, a yellowish-white tint, which varies to blackish and have been rolled for some time before being dropped off in the place where we collected them. It was from this cave, among other things, that I removed bones of bears, hyenas, and several rhinoceroses, etc., which showed me that these bones could only have been deposited there by water. Finally, on the right, entering the second cave, is a gallery which is only a continuation of the limestone which extends under a vault in this place, and which leads into another gallery, the longest of all, having little height and width. Both have provided me with bones lying in the same soil than that of the neighbouring caves, but less numerous than in the second that we have just described.”

In section IV, ‘Human Fossil Bones in Particular’, Schmerling recounts:

“Human bones are too well known for me to need to enter into a detailed description of these remains. It is more important not to neglect anything with regard to their deposit, and first of all I observe that these human remains, which are in my possession, are, like the thousands of bones that I have recently unearthed, characterized by their degree of decomposition, which is absolutely the same as those of extinct species; all are broken, with a few exceptions; some are rounded, as often occurs in the fossil bones of other species. The breaks are vertical, or oblique, none showing traces of erosion, the colour does not differ from that of other fossil bones, and varies from yellowish-white to blackish. All are lighter than normal bones, with the exception of those which are covered with a layer of calcareous tuff, or whose cavities are filled with such concretions.

The skull which I had represented, plate I, fig. 1-2, is from an elderly individual. The sutures begin to fade, all the facial bones are missing, and only a fragment of the temporal bone on the right side has been preserved.

The face and the base of this skull were removed, before it was deposited in this place since after having regularly exploited all this cave, we could not find these remains. It was a meter and a half deep that we encountered this skull, hidden under a bony breccia, made up of the remains of small animals, and containing a rhinoceros tooth, and some of horse and ruminants. This breccia, of which we have spoken, p. 31, was a meter wide, rising a meter and a half above the floor of the cave, and adhering strongly to the wall.

The earth, which contained this human skull, indicated no disturbance; rhinoceros, horse, hyena and bear teeth surrounded him on all sides.

The famous Blumenbach (1) exposed the differences in the shape and dimensions of human skulls of different races. This important work would have been of great help to us if the face, an essential part in determining race with more or less certainty, were not lacking in our fossil skull. We are convinced that, from a single sample, we cannot at all say with certainty, even if this head would be complete, because the individual shades are so numerous in the skulls of the same race, that one cannot without to expose oneself to the greatest consequences, to conclude from a single fragment of the skull for the total shape of this head.

(1) Decas Colleclionis suae craniorum diversarum genliitm illustrala, Gotùngae, 1793- 1820.

However, not to neglect anything concerning the shape of the skull fossil that we have collected, we will observe that the form elongated and narrow forehead first fixed our attention.

Indeed, the little elevation of the frontal, its narrowness and the shape of the eye sockets, bring it closer to the skull of the Ethiopian than to that of the European, the elongated shape, and the developed state of the occiput, are still characters which we believe to have noticed in our fossil skull, but to avoid any doubt in this regard, I have made represent the outline of the skull of a European, and of an Ethiopian, and the fronts shown on plate II, fig. 1, i, same plate, fig. 3 and 4, will be enough to distinguish the differences, and a single glance at these figures will say more than a long and boring description.

Whatever judgment we make on the origin of the individual where this fossil skull comes from, we can, it seems to us, express our opinion without exposing ourselves to a controversy, the outcome of which would be without positive result.

Each one, moreover, is free to choose the hypothesis which seems to him the most founded; as for me, it is shown to me that this skull belonged to an individual whose intellectual means were not very developed, and we conclude that it comes from a man whose degree of civilization was not to be very advanced this which we can realize by comparing the capacity of the forehead with the occipital part.

Another skull, of a young individual, was on the bottom of this cave, next to an elephant tooth; this skull was whole until the moment when I wanted to collect it, it then fell to pieces that, I have not, as yet, been able to put it together again. But I have represented the bones of the upper jaw, plate I, fig. 5. The state of the alveoli and teeth shows us that the molars had not yet pierced the gums. Detached milk molars, and some fragments of human skull come from this same place.

Figure 3 shows a human upper incisor tooth, which, by its size, is truly remarkable.

Figure 4; is a fragment of the upper jaw bone, the molar teeth of which are worn down to the root.

I have two vertebrae, a first and a last dorsal.

A clavicle on the left side, (see plate III, figure 1); although having belonged to a young individual, this bone announces the rather large size of this individual.

Two fragments of radius, badly preserved, do not indicate to me that they belonged to an individual whose dimensions exceeded the height of the man, being five and a half feet.

As for the remains of the upper extremities, those in my possession are limited to a fragment of ulna and radius. (plate III, fig. 5 and 6.)

Figure i of plate IV, represents a bone of the pastern, contained in the breccia we have spoken of; it was in the lower part, above the skull; add to this a few bones of the pastern, drawn from very different distances, half a dozen metatarsals, three phalanges of the hand and one of the foot. Here is the succinct enumeration of the remains of human bones collected in the cave of Engis, which has preserved for us the remains of three individuals, surrounded by those of the elephant, the rhinoceros, and predators of species unknown in the present creation.”

Human fossils from the lower Engis Cave. All except Fig. 5 were from modern humans, the maxilla, however belonged to the infant Neanderthal, whose skull is known as Engis 2. image credit: Schmerling (1833-4) via Orbi (2021).

Lastly, Schmerling, also realised that, the flint objects found in association with human and animal bones were actually man-made.

Schmerling’s publication of his finds, with its lucid writing and huge number of beautifully drawn plates provided a catalyst for further debate on the antiquity of man. Such luminaries as Geoffroy St. Hilaire, William Buckland, Charles Lyell and others visited Schmerling and examined his fossil collection.

Huxley (1863) in his book, Evidence as to Man's place in Nature, has a chapter entitled “On Some Fossil Remains of Man”. Here he compared the Engis I skull (Figs. 1 an 2 above) with the skull from Kleine Feldhofer Grotte in the Neandertal valley. He compared the two skulls, then compared them to the various ‘races’ of man. He explores the shape of the face, the dimensions of the various skulls, their development of the supraciliary ridges a, from such populations as Australians, Tartars, Danish, Negros, Calmucks (Mongolians) and “and of a well developed round skull from a cemetery in Constantinople, of uncertain race, in my own possession”. He also compared cranial capacities, where available. In conclusion he writes:

“But taking the evidence as it stands, and turning first to the Engis skull, I confess I can find no character in the remains of that cranium which, if it were a recent skull, would give any trustworthy clue as to the Race to which it might appertain. Its contours and measurements agree very well with those of some Australian skulls which I have examined—and especially has it a tendency towards that occipital flattening, to the great extent of which, in some Australian skulls, I have alluded. But all Australian skulls do not present this flattening, and the supraciliary ridge of the Engis skull is quite unlike that of the typical Australians.

On the other hand, its measurements agree equally well with those of some European skulls. And assuredly, there is no mark of degradation about any part of its structure. It is, in fact, a fair average human skull, which might have belonged to a philosopher, or might have contained the thoughtless brains of a savage.

The case of the Neanderthal skull is very different. Under whatever aspect we view this cranium, whether we regard its vertical depression, the enormous thickness of its supraciliary ridges, its sloped occiput, or its long and straight squamosal suture, we meet with ape-like characters, stamping it as the most pithecoid of human crania yet discovered…

In no sense, then, can the Neanderthal bones be regarded as the remains of a human being intermediate between Men and Apes. At most, they demonstrate the existence of a man whose skull may be said to revert somewhat towards the pithecoid type...

And indeed, though truly the most pithecoid of known human skulls, the Neanderthal cranium is by no means so isolated as it appears to be at first, but forms, in reality, the extreme term of a series leading gradually from it to the highest and best developed of human crania. On the one hand, it is closely approached by the flattened Australian skulls, of which I have spoken, from which other Australian forms lead us gradually up to skulls having very much the type of the Engis cranium. And, on the other hand, it is even more closely affined to the skulls of certain ancient people who inhabited Denmark during the 'stone period'..

The correspondence between the longitudinal contour of the Neanderthal skull and that of some of those skulls from the tumuli at Borreby, very accurate drawings of which have been made by Mr. Busk, is very close. The occiput is quite as retreating, the supraciliary ridges are nearly as prominent, and the skull is as low. Furthermore, the Borreby skull resembles the Neanderthal form more closely than any of the Australian skulls do, by the much more rapid retrocession of the forehead. On the other hand, the Borreby skulls are all somewhat broader, in proportion to their length, than the Neanderthal skull, while some attain that proportion of breadth to length (80:100) which constitutes brachycephaly.

In conclusion, I may say, that the fossil remains of Man hitherto discovered do not seem to me to take us appreciably nearer to that lower pithecoid form, by the modification of which he has, probably, become what he is. And considering what is now known of the most ancient races of men; seeing that they fashioned flint axes and flint knives and bone-skewers, of much the same pattern as those fabricated by the lowest savages at the present day, and that we have every reason to believe the habits and modes of living of such people to have remained the same from the time of the Mammoth and the tichorhine Rhinoceros till now, I do not know that this result is other than might be expected.

Where, then, must we look for primaeval Man? Was the oldest 'Homo sapiens' pliocene or miocene, or yet more ancient? In still older strata do the fossilized bones of an Ape more anthropoid, or a Man more pithecoid, than any yet known await the researches of some unborn palaeontologist?

Time will show. But, in the meanwhile, if any form of the doctrine of progressive development is correct, we must extend by long epochs the most liberal estimate that has yet been made of the antiquity of Man.”

Despite the fact that Huxley was a diligent and thoughtful scientific investigator, by the standards of his day, there is a double irony attaching to his assessments of the fossils he chose to discuss.

Firstly, less than a year later, King (1864a and b), published his assessment of the Kleine Feldhofer Grotte cranium as a new species, namely Homo neanderthalensis. Secondly, the other skull collected at lower Awirs cave was, although juvenile, actually a Neanderthal too. So near, but so far in terms of your name living on in scientific posterity!

A diagnosis of the Engis 2 cranium as a Neanderthal would not be written until, over a century later, by Fraipont, (1936). The lower of the Engis caves was investigated by numerous excavators over the next 125 years. These included  archaeological investigations: in 1868 by the geologist Éd. Dupont, in 1885 by the palaeontologist J. Fraipont, then by other people such as É. Doudou from 1895 onward and J. Hamal-Nandrin in 1904; finally, over the 20th century, by teams from the 'Chercheurs de la Wallonie' association, notably in 1907 and 1956.

Although, the Engis 2 cranium had been assigned to Homo Neanderthalensis early in the 20^th century, Tillier (1983) provided a modern analysis. She concludes her study of the Engis 2 cranium thus:

“During our study we compared the metric and morphological data of the skull of Engis 2 with those of other Neanderthal children and with those of a sample of current skulls whose dental age was between 5 and 10 years. Some initial remarks can be made regarding the development of the Neanderthal skull.

Among the dimensional characteristics of the skull of Engis 2 which deviate from the data collected on current subjects we can retain the frontal width and the interorbital width the biporic width, and the biasteric width, the maximum width of the skull: all these measurements are large on Engis 2 while the bimastoid width, for example, remains close to the current average value. In addition to these dimensions, the lambdoid parietal curvature index and the sagittal occipital curvature index are lower on Engis 2.

Certain metric characters of the skull of Engis 2 contrast with the data known in Neanderthal adults. Thus the bregmatic and frontal Schwalbe angles, the sagittal parietal curvature index are placed outside the variation limits for adults. Such an arrangement is found for the frontal on the Teshik-Tash skull while the sagittal parietal curvature index corresponds to the lower limit of adult Neanderthal variation. On the temporal on the other hand, the height / length index of the scale and that giving an idea of ​​the development of the mastoid process in relation to the length of the scale distance Engis 2 from Neanderthal adults and bring it closer to current children.

Most of the derived morphological characters retained on the skull of the adult Neanderthal are already recognizable in the child of Engis 2. as shown by the parietal. the occipital and the temporal. The morphology of the maxillo-malar region in extension can be considered without being demonstrated (in the absence of bone support); the study of the maxilla of Gibraltar 2 (Tillier 1982) found on the other hand, that the development of maxillo-malar angulation could be variable.

Some characters, in relation to the young age of the subject, are only sketched out on Engis 2, such as the suporbital torus, the separation of the petrotympanic crest and the mastoid process, or absent such as certain occipital temporal reliefs and frontal pneumatization.

Finally, other characters, present on Engis 2, have no significant value from a phylogenetic point of view, such as the relative development of the posterior zygomatic tubercle, the great width of the digastric groove or the small size of the teeth (except of dc M1 and dm2).

The attribution of the skull of Engis 2 to the group of Neanderthals cannot therefore be called into question. He represents with the men of Spy, with whom he shares certain characteristics such as the width of the digastric groove and the relative development of the posterior zygomatic tubercle (Spy I) or the single suprasiniac fossa (Spy 2), the best-known representatives of this evolutionary morphological stage in Belgium. Engis 2 also constitutes a reference element in the ontogenetic study of the Neanderthals, the importance of which can no longer be neglected.”

Tillier (1983) showing the principle frontal sutures. Original caption reads: Norma frontalis of the skull of Engis 2 showing the outline of the supraorbital torus.

Rear view of the occipital region of Engis 2 showing the spreading of the supra-iniac fossa and the insertion of large complexus [broad muscle lying along the back part of the neck, connecting the occiput and the lower cervical and upper dorsal vertebræ].. From Tillier (1983).

The dates for the Engis 2, Neanderthal infant have been somewhat contentious. Toussaint and Pirson (2006) obtained dates of ca. 26,820 and 30,460 BP on cranial fragments. These are regarded as too young.

Even the author [Toussaint (2011)] comments: “As for chronostratigraphy, the only information available comes from radiocarbon dating. Two contiguous fragments of the left parietal of the Neanderthal child thus provided two dates (Toussaint & Pirson, 2006a). The first, 26,820 ± 340 B.P. (OxA- 8827; delta 13C = -19.3), is far too recent in view of the regional and north-western European context to be acceptable. Even the second, 30,460 ± 210 B.P. (GrA-21545), hardly makes sense in the archaeological context from the Bassinmosan where such a date is more in phase with a fairly old Aurignacian.”

Devièse et al. (2021) finally achieved more reasonable dates for Engis 2. The researchers took collagen samples from Neanderthal skeletal remains originally found in 1829.

While taking collagen samples for radiocarbon dating is a standard technique used to date fossils, the researchers had to use an advanced purification method Using liquid chromatography in order to separate the collagen samples from all contaminants. They found that the contaminants arising from the actual methods of preservation themselves, including glue prepared from bovine bones used to preserve skeletal remains had affected the radiocarbon dates, making them appear too young.

Using this process, the researchers were able to isolate just one molecule — a single amino acid — in order to increase the accuracy of the radiocarbon date read.

Based on these new radiocarbon dates, the authors of the study estimate that the Neanderthal child, Engis 2, dates to between 40,600 and 44,200 years ago. 

Other parts of the Engis assemblage have also provided a greater depth of understanding, in terms of Neanderthal child development. In particular, the partial mandible found, and illustrated by Schmerling (1833-34) has been studied in depth.

The Engis partial mandible found by Schmerling from Parg, (2015).

Futher research has included an ontogenetic analysis was carried out by Smith et al. (2010). In this very illuminating study, a new age at death was calculated for the Engis 2 Neanderthal child, using the unerupted teeth in the mandible recovered from the lower Engis cave. The authors explain the variables they measured and how these result in an accurate age at death, they stated: “To calculate crown formation time, molar eruption age, and age at death, we quantified the following standard developmental variables: cuspal enamel thickness, long-period line periodicity (number of daily increments between successive long-period lines), total number of long-period lines in enamel (Retzius lines or perikymata), and coronal extension rate (speed at which enamel forming cells are activated to begin secretion along the enamel-dentine junction) in 90 permanent teeth from 28 Neanderthals and 39 permanent teeth from 9 fossil H. sapiens individuals…

Combining histological data on initiation ages, crown formation times, and root formation times yields age-at-death estimates for six Neanderthal and two fossil H. sapiens juveniles.” They arrived at an age of 3.0 years for the Engis 2 Neanderthal, individual, at death. 

Scan of the Engis 2 maxilla, showing unerupted permanent incisors and canines, from Smith et al. (2010). Original caption reads: Fig. 1. Virtual histology of the maxillary dentition from the 3-y-old Engis 2 Neanderthal. (A) Synchrotron micro-CT scan (31.3-μm voxel size) showing central incisors in light blue, lateral incisors in yellow, canines in pink, and third premolars in green. (Deciduous elements are not rendered in color as they were not studied.). Scale bars in A and B, 10 mm.

To this day the Engis 2, cranium of the Neaderthal child justly, fascinates archaeologists and palaeoanthropologists and the public alike. It is a poignant relic of a life cut brutally, short. I wonder what the youngster thought and felt in the months leading up to their untimely demise? Did they play along the banks of the Awirs stream below and was it some chance accident or disease, that brought about their death? Did their parents bury them in the cave with as much grief as a modern family would have? These are the unanswerable questions that haunt me.

Engis 2 virtual reconstruction by John Hawks (2021) – I wonder what he or she looked, in the flesh?

References

27 Crags (2017). At: https://27crags.com/crags/awirs/photos accessed 19/08/2021

Devièse, T., Abrams, G., Hajdinjak, M., Pirson, S., De Groote, I., Di Modica, K., Toussaint, M., Fischer, V., Comeskey, D., Spindler, L. and Meyer, M., 2021. Reevaluating the timing of Neanderthal disappearance in Northwest Europe. Proceedings of the National Academy of Sciences, 118(12).

Fraipont, C. (1936) Les hommes fossiles d'Engis. Archives de l'institut de Paléontologie Humaine. Memoire, 16: 52 p.

Hawks, J. (2021). Neanderthals. At: https://twitter.com/johnhawks/status/1367226871948185603 accessed 18/08/2021

Huxley T. H. (1863). On Some Fossil Remains of Man, in Evidence as to Man's place in nature. Williams & Norgate, London.

King, W. (1864a). On the Neanderthal Skull, or Reasons for believing it to belong to the Clydian Period, and to be a species different from that represented by Man, Report of the British Association for the Advancement of Science. London. 33rd Meeting (1863), p81-82

King, W. (1864b). The reputed fossil man of the Neanderthal. Longmans Green & Company.

Orbi (2021). Recherches sur les ossemens fossiles découverts dans les cavernes de la province de Liège. Down load at:  https://orbi.uliege.be/handle/2268/207986 accessed 17/08/2021

Parg, P. (2015). Engis 2 Maxilla. At: https://commons.wikimedia.org/wiki/File:Engis_2_Maxilla.jpg accessed 18/08/2021

Schmerling P.-C. (1833-34) – Recherches sur les ossemens fossiles découverts dans les cavernes de la province de Liège, P.-J. Collardin, Liège, 2 tomes de 167 et 195 p.

Smith, T.M., Tafforeau, P., Reid, D.J., Pouech, J., Lazzari, V., Zermeno, J.P., Guatelli-Steinberg, D., Olejniczak, A.J., Hoffman, A., Radovčić, J. and Makaremi, M. (2010). Dental evidence for ontogenetic differences between modern humans and Neanderthals. Proceedings of the National Academy of Sciences, 107(49), pp.20923-20928.

Tillier,  A.-M. (1983) Le crâne d'enfant d'Engis 2: un exemple de distribution des caractères juvéniles, primitifs et néanderthaliens. Bull. Soc. roy. belge Anthrop. Préhist., 94 :51-75.

Toussaint M. and Pirson S. (2006). Neandertal Studies in Belgium : 2000-2005. Periodicum Biologorum, 108: 373-387.

Toussaint, M., Semal, P. and Pirson, S. (2011). Les Néandertaliens du bassin mosan belge: bilan 2006-2011. Le Paléolithique moyen en Belgique, pp.149-196.

Pre-Clovis Archaeological sites of the Americas 8: Chiquihuite Cave, Mexico

Last year Ciprian Ardelean et al. (2020), published a paper in Nature: “Evidence of human occupation in Mexico around the Last Glacial Maximum.” This is a seminal paper, as every possible, modern archaeological technique, was thrown at the excavation by the team from the Autonomous University of Zacatecas and other institutions.

During the 8 years of excavations at Chiquihuite, starting in 2012, Ardelean and his team found ca. 2000 stone tools of various types. These included scrapers, hand axes, spear points, and projectile points.

The location of Chiquihuite Cave and other pre-Clovis sites in the Americas. It is interesting that a section of the cave is marked for future excavation. Original caption reads: The state of Piauí includes five sites: Toca do Boqueirão da Pedra Furada, Vale da Pedra Furada, Toca do Sitio do Meio, Toca da Tira Peia and Toca da Janela da Barra do Antonião-North. Sources: the journal Nature (Chiquihuite cave, early human settlements); Geological Survey of Canada (ice sheets); Paleoindian Database of the Americas (late Pleistocene coastline) Image credit: Hotz (2020).

The team on the approach to Chiquihuite Cave Sierra El Astillero mountains. No external view of the cave seems to be available on the internet, beyond the long shot in the paper itself. This may be due to the region being controlled by drug cartels. Consequently the scientists needed a police escort when trekking to and from the cave. Image credit: Brackley (2020).

Location of the cave below Chiquihuite Peak, from Extended Data Fig. 1c Ardelean et al. (2020), shown by the arrow.

Archaeologists entering Chiquihuite Cave, from Middle East Online (2020).

Ardelean explained the circumstances of the initial exploration of the cave, in an interview to Hotz (2020): “For a decade, Dr. Ardelean searched the state of Zacatecas for evidence of early human settlement. He explored 35 sites with no luck. In 2010, local villagers told him of the remote Chiquihuite Cave. When Dr. Ardelean and his colleagues first ventured into its inky interior, he expected little more than a coyote den.

He was surprised to discover two vast vaulted interconnected chambers steeply sloping down into the heart of the mountain. “We were shocked by the size of everything,” he said.

In 2012, they dug a test pit in the loosely compacted gravel, sand and fragmented rock about 150 feet from the cave entrance. The deeper they dug, the harder it was to keep the walls of the pit from collapsing. “When I left the cave, I was convinced I had nothing,” he said. “I had several bags of rocks with me that somehow looked suspicious.”

In the laboratory, they identified three hand-flaked stone chips created during toolmaking, the charred remains of palm plants and the bone from a bear’s penis. Radiocarbon dating of the bone and charcoal suggested they might be around 27,000 years old, he said.

“That rang the alarm,” he said.

In three years of fieldwork, they recovered more than 1,900 tools made from small distinctive chunks of greenish limestone not normally found inside the cave. The sharpened points, blades and scrapers had been crafted with soft hammer blows, likely from a wooden or bone striker, Dr. Ardelean said. They “looked like nothing else he had seen in the Americas.”

In the body of the paper, Ardelean et al.  (2020) explain how the chronology of the cave was elucidated using radiocarbon dating and optically stimulated luminescence (OSL) methods:

“We obtained 46 radiocarbon determinations from a total of 59 samples (bone, charcoal and sediment), as well as 6 optically stimulated luminescence (OSL) dates from a total of 8 samples. The chronology at Chiquihuite Cave is principally constructed using radiocarbon dating, with OSL dates providing an independent control. Sample selection was aimed at maintaining a close spatial relationship with lithic artefacts found along the sequence.

All bone samples with reported elemental and isotopic data (n = 6) had collagen yields, C: N atomic ratios and per cent carbon values that fell within accepted ranges (greater than 1% (weight), 2.9–3.5 and 30–50% (weight), respectively. This indicated acceptable collagen preservation and likely low levels of contamination.

All the chronometric data we obtained were incorporated into a Bayesian age model..

Modelled output estimates the start of SC-C as being before the LGM, at 33,150–31,405 calibrated years before present (ad 1950) (cal. bp) (all ranges are given at 95.4% probability); SC-B dates to between 16,605–15,615 cal. bp and 13,705–12,200 cal. bp (close in date to the Younger Dryas, at about 12,900–11,700 years ago). The entire sequence spans 20,090–17,830 years. Within the sequence, we identified a considerable gap between strata 1218–1219 and stratum 1217 that fits within the LGM, and probably indicates decreased human presence and reduced sedimentation. Overall, the chronological sequence for Chiquihuite Cave is in excellent agreement with the stratigraphic evidence.”

Ardelean et al.  (2020), Fig. 2 showing the chronology of the sediment layers. The key point is that layer SC-C with the lithics that “looked like nothing else he had seen in the Americas.” dates to 33,150–31,405 cal. bp (pre-LGM).

A larger view of the excavation. Soil sample collection in progress, from Ars Technica (2020).  Additionally, a good digital, 3D model of Chiquihuite Cave has been produced by Gandy (2021).

Let us look at the lithics in question.

Lithics from layer SC-C. All from Extended Data Fig. 5: Additional Chiquihuite Cave Lithics Ardelean et al.  (2020). Scale bar = 1cm. i and n flakes; o blade; b’, c’ and f’ points.

Top: k’ point from layer SC-C. All from Extended Data Fig. 5: Additional Chiquihuite Cave Lithics Ardelean et al.  (2020), scale bar 1cm. Middle: flake from SC-C; Bottom: Point from SC-C both from Fig 3. Ardelean et al.  (2020), middle and bottom, scale bar = 3cm. With respect to m, the Fig 3. caption gives the following, additional information: “One Pseudotsuga sp. (Douglas fir) charcoal fragment closely associated with the bifacial preform shown in m in stratum 1223 was dated to 27,929 ± 82 uncalibrated radiocarbon years bp.” This lithic point or ‘bifacial preform’ must have a calibrated date, close to the 33,000 bp maximum date, for the chronological sequence, stated above.

Point from Chiquihuite Cave, from Hotz (2020). Original caption reads: Scientists said they unearthed hundreds of unusual green limestone spear points, blades and other implements from the Chiquihuite Cave. Photo: C. Ardelean.

Scraper (?) excavated from below the LGM boundary at Chiquihuite Cave, from Curry (2020a). Original caption reads: Stone tools like this one, from deep in Chiquihuite Cave in Mexico, suggest people lived there at least 26,000 years ago. C. Ardelean.

Whilst Ardelean, stated in interview [Hotz (2020)], that the lithics “looked like nothing else he had seen in the Americas.”, others disagree. Boëda et al. (2020), provide the following observations on the lithics from layer SC-C: “Regarding the lithic material, the authors emphasize that the artifacts made on flakes do not reflect any known technical tradition. Only 13 lithic artifacts of the SC-C component are illustrated in the article, so it is not possible to comment further on the accuracy of this claim. In the paper’s Methods section, the authors note that “Inductive references to known Paleoamerican typologies were avoided”. From our perspective, this is the best way to approach the lithic industries that we do not know, given that early Paleo-American typologies are currently being (re)constructed, and none of them presents sufficient extraregional heuristic power to be used in a generalized manner of comparison.

The preliminary morpho-technical typological classification adopted by the authors reports the presence throughout the Chiquihuite sequence of cores, flakes, blades, bladelets, medial fragments of blades, modified or used flakes, scrapers (circulars forms and end scrapers), burins, backed knives, points, adzes, and point-like objects. All of these types of artifacts, individually or collectively, are present in the South American Pleistocene sites dating to before, during, and after the LGM, made on limestone and other raw materials, notably basalt and andesite in the western sector of the southern continent, and mainly quartz and quartzite in the eastern sector. Perhaps the only novelty is the presence of bifacial pieces and laminar elements in the older components. The so-called “bifacial preform” from stratum 1223 (27,929 ± 82 14C yr BP) is the most ancient bifacial piece reported to date in the Americas. Given the excessive attention given to bifacial pieces in American prehistory, perhaps this evidence will promote a recognition of the anthropogenic character of associated non-bifacial artifacts, largely forgotten from any detailed technological

study. Nevertheless, the few lithic pieces illustrated in Ardelean et al. (2020) present an indisputable anthropogenic character, in addition to the obvious techno-functional coherence of each piece individually.

The fact that some researchers are already ruling against the anthropogenic nature of these artifacts (e.g., Curry 2020b) reflects a usual ad hoc assumption – proof of a lack of knowledge of the technical specificities of lithic materials, and in particular of South American industries. The authors emphasize that “transverse points” are a recurring feature throughout the Chiquihuite stratigraphic sequence, also present in the SC-C component.

Another recurring element is marginal retouching (referred to as “edge trimming”). Whether it is unifacial or bifacial retouching, this technique was used to modify flakes into tools. These two technical characteristics are also present in South American Pleistocene sites, in particular those located in northeastern Brazil, where we have recognized “convergence” of worked margins, avoiding the ambiguous term “point.” We use the term “convergence” to refer to a particular techno-type of tool in northeastern Brazil, made up of two edges that form a convergence due to a retouching or shaping operation. The term “point” is functional in nature, while the term “convergence” is rather technofunctional in nature.”

Boeda et al., (2020), then provide figures drawn from other, recent papers, that show, that similar lithics have been excavated in South America:

Figure 1 Locations of sites referenced in the text, dates of those sites, and artifacts representative of their lithic industries (the figure elaborated from and based on Boëda et al. 2014, 2016; Lahaye et al. 2019; Lahaye et al. 2013; Vialou et al. 2017).

Boeda et al. (2020), go on: “In the northeast of the Brazilian state of Piauí (Brazil), our team and others (Guidon 1989; Parenti 2001) have recorded several different geological contexts (cuesta, terrace, valley, limestone massif, cave, rock shelter) with long archaeological sequences. In the limestone karst zone, we reported three sites with Pleistocene archaeological sequences, containing remains of mesofauna and megafauna: Toca da Pena, Tira Peia, and Toca da Janela da Barra do Antonião-Norte (TJBA-N) (Figure 1). These sites share several characteristics with Chiquihuite Cave. For example, in the rock shelter of Tira Peia, a site located on a limestone massif, we have recovered a large number of lithic artifacts made on quartz and quartzite pebbles, and limestones rich in silica in the C6 and C7 layers, dated between 20,000 and 15,100 cal yr BP (Lahaye et al. 2013). Additionally, a dozen similar artifacts were found in layers C8 and C9, exceeding 22,000 cal yr BP (Boëda et al. 2013). One km northeast of Tira

Peia, the C5a layer of TJBA-N has been dated between 19,000 and 20,400 cal yr BP, containing lithic artifacts on quartz and quartzite (Lahaye et al. 2019). Likewise, in the cuesta area, the first occupation of Sítio do Meio, dated between 35,000 and 28,000 cal yr BP and with an occupation gap between 28,000 and 24,000 cal yr BP, presents a phenomenon of microlithism evident in the quartz-pebble industry (Boëda et al. 2016, figure 6). All of these sites yielded lithic artifacts that cannot yet be traced to any known Paleo-American technocultural tradition, but that does not mean they do not exist.”

Faunal and human DNA from Chiquihuite Cave

The most interesting aspect of the excavation was the collection of sediment samples for environmental DNA testing. The main reason was to ascertain whether any ancient DNA, comparable to the date of the oldest layers with human-made lithics. As this ancient DNA would be from pre-Palaeoindian times, it would be extremely interesting to find out who the makers of the tools were most closely related to, and thus where these early migrants to the Americas, originated. Unfortunately, according to the authors, they found none. Except that isn’t strictly true. They actually, did detect human DNA at various points throughout the sequence. I’ll come back to that later.

Scientist collecting soil samples for eDNA testing, from NBC News (2021) 

In terms of the faunal DNA, a great deal was found, as Ardelean et al. (2020) say: “Among the fauna, bat DNA is present in all layers. This is dominated by Eptesicus sp., Myotis sp. and Vespertilionidae, until stratum 1204, in which Phyllostomidae, Desmodus sp. and new Microchiroptera species replace the previous assemblage. By contrast, although bear DNA (Ursus sp.) appears during the LGM, the highest abundance occurs during the termini, which is in concordance with the archaeological evidence2,19 (Supplementary Information 1.5, Supplementary Fig. 7). Rodents (Marmota sp., Microtus sp., Ictidomys sp., Urocitellus sp. and Peromyscus sp.) are present throughout the sequence, with a higher incidence in a few of the strata. Deer mouse (Peromyscus sp.), vole (Microtus sp.) and marmot (Marmota sp.) appear to be more abundant than other rodents, with kangaroo rat (Dipodomys sp.) appearing in the youngest stratum (stratum 1201). DNA findings also include goat (Caprinae, probably Oreamnos sp.) and sheep (Ovis sp.), as well as a low proportion of DNA from birds, such as sparrow (Zonotrichia sp.), falcon (Falco sp.) and tanagers (Thraupidae).”

I found this vague list, with its assignment to the level of genera only, quite frustrating. I therefore looked at the relevant Supplementary Information sections, to see if more detail was given. I was surprised to find which reference genomes the authors chose to use. Here are a few examples.

Marmota sp. From their Supplementary Data Ardelean et al. (2020), the reference genome used was Marmota marmota. This is the Alpine Marmot, of European only distribution. This is particularly odd as a recent paper resolving the phylogeny of all 15 Marmota sp. was published by Steppan et al. (2011). The paper notes areas for fossil finds of Marmota, with Marmota flaviventris, the yellow-bellied marmot, previously found in New Mexico. It was therefore, probably this species that is represented by the DNA and fossils from Chiquihuite Cave.

Another important group of fossils and eDNA, samples, from the cave are those assigned to Equus or horse species. Some of these are from early in the sequence, meaning they were native Equus species making them doubly interesting. Consulting “Extended Data Fig. 4 Taxonomic profiles of animals (Amniota) and plants (Viridiplantae) identified by ancient environmental DNA.”, one finds that Equus sp. DNA was found in strata UE1217, UE1218 and UE1223. These strata, range in modelled age from ca. 25,000 bp, (UE1217) or around the LGM to ca. 31,550 bp UE1223 – see Ardelean et al. (2020), Fig 2. Not only that but two species of Equus were found. This is very exciting! Looking at the reference (Supplementary Data) genomes used were Equus przewalskii and Equus asinus. Once again these are both odd choices for the reference genomes.

Taking Equus przewalskii first, this is the Eurasian Wild Horse, which, in the prehistoric era ranged over central Asia, China, and western Europe. This is, and never was an American species. Again, reference genomes for north American wild horses from the same region of Chiquihuite Cave, were available from a paper by Barron-Ortiz et al. (2017). Their conclusion reads: “Two equid species, Equus ferus and E. conversidens, are identified for the late Pleistocene of the Western Interior of North America, based on molecular and morphological analyses of the cheek teeth. A third species, E. cedralensis, is provisionally recognized based exclusively on the morphological analyses of the cheek teeth.” Despite the rather confusing assignment of one clade from their DNA and morphological studies to Equus ferus, the fact remains that they identified three, distinct species. All were found in the region of Chiquihuite Cave. Lastly Machado and Avilla (2019) used morphometric on a large number of specimens of to suggest that all species of Equus from south America should be synonymised under a single species: Equus neogeus. While only a partial sequence for this species have been published (see Orlando et al. 2008), I would have hoped that, Ardelean et al. (2020), would have compared their sequences to this available data and the other, Equus DNA sequences available.

A second species of Equidae was also discovered via eDNA sampling by Ardelean et al. (2020). Once again looking at the Supplementary Data spreadsheet we find an even more extraordinary choice of reference genome, namely Equus asinus. By ‘Equus asinus’ I can only assume the authors mean the Asinus subgenera of Equus, commonly known as the Eurasiatic wild ass. These include the African wild asses, (ancestor of the domesticated Donkey), Onagers from the Asian steppes and Kiang, the Tibetan wild ass. While it is possibly found in the topmost layer [UE1201] as a feral species introduced at the time of the conquistadores, the other DNA samples recovered from throughout the sequence going right down to UE1223, dated ca. 31,500 bp simply cannot be members of this species group.

I cannot fathom the assignment of these DNA samples to this reference genome, nor the lack of comment on this glaring anomaly by other reviewers of the paper.

 

The last example I wish to look at is Urocitellus parryii, the Artic Ground Squirrel. Once again a quick check on the phylogeny of the genus, brings up adequate references to DNA studies on Urocitellus. Herron et al. (2004) and Helgen, et al. (2009) revise the taxonomy of this genus and give DNA sequences. To cut a long story short, the ground squirrel DNA found by Ardelean et al. (2020) in stratum UE1207C (modelled at 25,000 to 17,000 bp) cannot be Urocitellus parryii as this is a circum-polar species found in Canada, Alaska and Siberia. The most likely species seem to be, Urocitellus beldingi; Urocitellus mollis; or Urocitellus townsendii; considering their current distribution. Once again, I must ask why the authors chose the least likely reference genome form the 12 other, known species which might have provide a better fit in terms of likelihood of occurrence in the Chiquihuite Cave region.

I must therefore ask why these reference genomes were chosen. Was it the fact that they were the ones most widely available? Was it that, the DNA sequences recovered by Ardelean et al. (2020), were truly closest to the species that they were assigned to – although this seems unlikely from my discussion above. Another possibility is that the range of these Marmota, Equus, and Urocitellus species were formerly much greater, and once extended to northern Mexico. I guess we’ll have to wait for a more in depth paper? It would make most interesting reading, if indeed it is forthcoming.

Lastly, I come to the human DNA. Ardelean et al. (2020), unequivocally state: “we found no evidence of ancient human DNA within the samples”. This however is not the case. Abundant human DNA was found throughout the sequence of strata. It is the source that it originated from that is in question. In their XXXXX Ardelean et al. (2020) state: “We investigated the presence of ancient human DNA out by mapping sequencing reads of each sample against two different reference indices (see Methods). We first determined the presence of mitochondrial (MT) sequences by mapping against a reference index containing all mitochondrial genomes contained in the RefSeq database (release 92). Reads mapping uniquely and with high quality (MQ25) to a single MT reference contig were extracted and assessed for genomic coverage and ancient DNA damage. We find that only the sample from UE1210 contains sufficient human MT reads for analysis, with a total of 189 reads mapping at MQ25 and covering ~58% of the MT genome (contig NC_012920.1, Supplementary Metadata file).

However, rates of characteristic ancient DNA damage substitutions (5’ C>T or 3’ G>A) were indistinguishable from other substitution types, indicating that the reads originated likely from contaminating modern human DNA. This contrasts with reads mapped to the American black bear MT (contig NC_003426.1) from the same sample, which showed similar genomic coverage but elevated rates of 5’ C>T and 3’ G>A substitutions, consistent with authentic ancient DNA (Supplementary Metadata file, Fig. S62).

When using the full human genome as a reference index, we find reads mapping from all samples, with coverage ranging from 595 up to 32,727 reads at MQ25 (Supplementary Metadata file). For the majority of samples rates of ancient DNA damage substitutions were ≤ 0.01, again suggesting their modern origin. However, three of the strata (UE1210, UE1212, UE1215) exhibit elevated rates, ranging from 0.03 up to 0.07 (Supplementary Metadata file). As remnant, human background contamination present in the reagents used in the laboratory preparations will dilute or decrease the DNA damage signal of ancient human reads if present in only low quantities, we considered those samples as putative candidates for follow up.

A further complication for the ancient DNA authentication stems from the possibility of spurious mapping of reads that originate from DNA sequences conserved between humans and closely related species. If ancient DNA sequences of a closely related species are present in sufficient numbers in the sample, their spurious alignment to the human genome can create a false-positive signal of ancient DNA damage. To investigate whether this was the case for our samples, we re-calculated the substitution rates restricting to reads assigned to Old world monkeys (Hominidae) using the ‘Holi’ pipeline, parsing reads with mismatches ≤ 5 for all samples and controls. Substitution rates of 5’ C>T and 3’ G>A changes were indistinguishable from the other types after this filtering step (Fig S63-S65), suggesting spurious mapping as the main culprit for the elevated rates observed before.” 

Up to the part “However, three of the strata (UE1210, UE1212, UE1215) exhibit elevated rates, ranging from 0.03 up to 0.07”, I am in full agreement with Ardelean et al. (2020). Elevated levels of DNA damage is a key indicator that ancient DNA is present. The suggested reason for these samples being discarded as truly ancient human DNA, is ‘spurious mapping’ of the sequences onto ‘closely related species’. The modelled dates for strata UE1210 to UE1215 are ca. 17,000 to 19,000 bp, consequently if these samples DO represent ancient human DNA, they would be between 4,400 and 6,600 years older than that of the oldest DNA from the Americas: the Anzick Child at ca. 12,600 bp. Human DNA, from the Americas not only definitively break the ‘Clovis first’ hypothesis, it would almost certainly reveal a great deal about the origins of the earliest people (so far discovered) to migrate to the Americas.

So let us investigate what closely what ‘closely related species’ could be in northeastern Mexico at this time. Looking at the temporal window between 17,000 and 19,000 bp we are still in the slow thawing phase of the last glacial maximum. According to Vázquez-Selem and Lachniet (2017): “The LLGM (last local glacial maximum) in the mountains of Mexico (20-14 ka) and Central America (~21-18 ka) overlaps with the final part of the global Last Glacial Maximum (26.5-19 ka).” This is the period from which the ‘human’ DNA from stratum UE1215 originates. One has, therefore, to ask which ‘closely related species’ could be extant in northeastern Mexico at this time? The obvious candidates are the New World Monkeys (Infraorder Platyrrhini). A check on the phylogeny of New World Monkeys and Old World anthropoid revealed a paper by Schrago and Russo (2003), estimates the split of Platyrrhines split Catarrhines (the branch leading to (Homo sp.) at around 35 MYA.

Phylogeny of New World Monkeys and Old World Anthropoids, from Schrago and Russo (2003).

Roughly speaking, the conservation of stretches of DNA through time and the points at which these sequences diverge is used to put an age estimate on the split times for the different groups above. While some hominoid proteins evolved significantly slower than those of other primates, the mitochondrial clock rate was found to be more or less unaffected. In consequence, DNA sequences from before the split of NWM and OWA are conserved in NWM.

Therefore, the statement that ‘spurious mapping’ of the sequences onto ‘closely related species’ by Ardelean et al. (2020) is plausible.

Having said that, the question we must ask is whether there were any NWM in the Chiquihuite Cave region during the slow alleviation of the inhospitable climate in the region, in the wake of the LGM, between 19,000 and 17,000 bp? Consulting the literature very widely, I was unable to find any reference to fossil NWM from the relevant time-period. This is not to say that such fossils do not exist, but that they are not mentioned in any of the texts I consulted.

If we step back for a moment and consider the environmental adaptations of monkey species worldwide, one species capable of ling in cold, icy conditions at altitude does spring to mind. I am of course referring to the Japanese Snow monkey, Macaca fuscata. This Japanese macaque, inhabits subtropical forests in the southern part of its range and subarctic forests in mountainous areas in the northern part of its range. The macaque can cope with temperatures as low as −20°C and live up to and beyond 3,000m in altitude.

Japanese macaques seen in deep snow, from JRPASS (2021).

While it is possible that an analogous NYM, similar to the Japanese Snow Monkey did exist in northeastern Mexico at the relevant time, no fossils have ever been found, even by Ardelean et al. (2020).

One can therefore, only conclude on the balance of the evidence that, no New World Monkeys were extant in the region of Chiquihuite Cave between 19,000 and 17,000 years ago. This leads us to the inevitable position of having to accept that the samples of ‘human’ DNA from strata UE1210 to UE1215, with their characteristically damaged DNA and elevated rates of 5’ C>T and 3’ G>A substitutions, were consistent with authentic ancient DNA and were actually human and not from a ‘closely related species’.

Conclusions

1. The evidence of the lithics, C13 dating and OSL dating leads unassailable conclusion that humans were in north America ca. 31,500 bp.

2. Extremely valuable ancient Equus DNA samples were recovered from Chiquihuite Cave sediments which could help reveal the true phylogenic relationships, geographic distribution and dispersals of the genus in the Americas.

3. A robust chronology for the strata within Chiquihuite Cave was built using complimentary scientific methods. Human DNA was found in the sequence of strata and could be dated to 19,000 – 17,000 bp using this chronology.

4. The reference genomes used to identify various species/genera was somewhat inexplicable, while exclusion of human DNA and its attribution to ‘closely related species’, on flimsy evidence seems deliberately disingenuous. On this point, perhaps the authors didn’t want to give critics ammunition to knock the paper down. Put simply, I believe they were just playing it safe.

Acknowledgement: Hat tip to Marnie Dunsmore (2021) at the Linear Population Model blog who put many of us onto this site in 2017/2018(?). Unfortunately, I can’t go back and read her posts as the blog is now private and only open to invited guests.

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