Thursday 22 February 2024

The oldest known rock art in Patagonia, and what it tells us about the people who made it.

Patagonia lies at the southern tip of the Americas, and was one of the last areas to have been settled by Humans, who did not arrive there until the end of the Pleistocene. The area has a unique environment, which would have presented challenges to the people settling there. It also has a climate particularly suitable for the preservation of archaeological remains, making it particularly interesting to archaeologists. The area has extensive rock art, but to date little of this has been accurately dated.

In a paper published in the journal Science Advances on 14 February 2024, Guadalupe Romero Villanueva of the Instituto Nacional de Antropología y Pensamiento LatinoamericanoMarcela Sepúlveda of the Department of Social Sciences at the Universidad de Tarapacá, José Cárcamo-Vega of the Laboratorio de Espectroscopía Vibracional at the Universidad de ChileAlexander Cherkinsky of the Center for Applied Isotope Studies at the University of GeorgiaMaría Eugenia de Porras of the Instituto Argentino de Nivología, Glaciología  y  Ciencias  Ambientales, and Ramiro Barberena of the Centro de Investigación, Innovación y Creación at the Universidad Católica de Temuco, and the Instituto Interdisciplinario  de  Ciencias Básicas at the Universidad Nacional de Cuyo, present dates for four pieces of rock art from the Cueva Huenul 1 archaeological site in Neuquén Province, in the northern part of Argentinian Patagonia, and discuss the implications of this for the early peopling of the region.

The Cueva Huenul 1 archaeological site is located a kilometre above sealevel, to the east of the Andes amid the inland deserts of northern Patagonia. The Andes present a major topographic barrier, preventing the prevailing westerly winds from carrying moisture from the Pacific to the South American Arid Diagonal, where the Cueva Huenul 1 site is located. Precipitation in the region is between 150 mm and 200 mm each year, 75% of which falls in the winter. Rainfall tends to be higher in the west, closer to the Andes, and dryer to the east. with more abundant vegetation in areas with higher rainfall.

Location  of  Cueva Huenul 1,  other  sites  with  rock  art  in  northern  Neuquén  Province (Argentina),  and  palaeoecological  sites  from  northwestern  Patagonia. María Eugenia de Porras in Villanueva et al. (2024).

The Cueva Huenul 1 site is a cave with a habitable area of 620 m³, formed by the erosion of ignimbrites of the Tilhué Formation beneath an overlying basalt layer of the El Puente Formation, which have not eroded and now form the ceiling of the cave. Excavations within this cave have produced over 5500  lithic artifacts, principally flaked stone objects, and 8800 bone specimens, mostly Guanaco, Lama guanicoe. The site also has a long, and well-defined dating sequence, spanning 12 000 years, with a number of discrete phases of activity identified. The microenvironment within the cave appears to have remained stable and dry over this period, allowing for the excellent preservation of items such as Animal dung, and plant remains. 

Cueva Huenul 1 environment and landscape. (A) emplacement of Cueva Huenul 1 (yellow arrow) in a volcanic landscape within the Monte desert. (B) to( D) Views of the cave’s geology and topography. (E) View from Cueva Huenul 1 of the volcanic landscape of northwestern Patagonia. Guadalupe Romero Villanueva in Villanueva et al. (2024).

Notably, the Cueva Huenul 1 site has yielded a remarkable quantity of art-related materials, including  perforated  shell  beads, decorated Guanaco bones, and pyro- engraved  gourds. Also found inside the cave was a pit-structure containing a large number of twigs from the desert shrub Senna  aphylla, which have been stained with red ochre. A large amount of pigments, of various colours and in varying states of preparation.

Cueva Huenul 1 site plan and special findings. (A) excavation units at ch1. (B and C) General and detailed view of pit structure filled with vegetal remains of Senna  aphylla stained with red ochre. (D) Pyro-engraved gourd. (E) Perforated shell bead. (F) decorated guanaco (Lama guanicoe) bone. (G) Pigments. each image has an individual metric scale. Guadalupe Romero Villanueva and Ramiro Barberena in Villanueva et al. (2024).

The site has a panoramic view of the surrounding landscape, although it is not visible from any other known archaeological site in the region, nor can any such site be seen from the cave. Other sites in the region include a series of smaller caves and rockshelters, most of which only appear to have been used within the last 2000 years. Some of these, such as El Ciénego and Paso de las Tropas, also have rock art, although it is less diverse in technical style and less formalised than the art at Cueva Huenul 1. The Cueva Yagui site, to the north of Cueva Huenul 1, also records a long timeline, in this case about 8 500 years, and appears to have been more intensely occupied, on the basis of stone tools, abundant ceramics, and faunal remains, with this occupation being particularly intense over the past 2000 years. Both the stratigraphic sequences and the styles of rock art suggest that Cueva Huenul 1, Cueva Yagui, and other sites appear to have been linked.

Cueva Huenul 1 hosts one of the most impressive collections of rock art in northwestern Patagonia, with central portion of the cave’s internal wall and part of the ceiling covered by 895 discrete pieces of rock art, which have been grouped into 466 identifiable motifs. Most of these motifs are geometric shapes rather than pictures, with strokes, dots, circles, and lines being common, and parallel lines, reticulates, polygons, and cruciforms also present, as well as some Human silhouettes and a face, and silhouettes of Guanaco and Choique, Rhea pennata, and some representations of dynamic group  activities. A range of colours are used in the cave art, although a haematite-derived red is the most common, along with different hues of white, yellow, and black.

Examples of the rock art of Cueva Huenul 1. Each tracing has a 10cm scale bar. Guadalupe Romero Villanueva in Villanueva et al. (2024).

A large number of motifs are superimposed over earlier artworks, and there appear to be three distinct degrees of weathering, as well as distinct artistic phases. The majority of the art is presumed to be of Late Holocene origin, based upon similarities to styles of art used at other localities. However, the long history of occupation at the site combined with presence of a clear artistic sequence, raises the possibility that some art at the site may be much older.

Four artworks at the Cueva Huenul 1 site were chosen to be dated. These were all classified as 'comb-shapes' based upon a shared basic morphology of a perpendicular horizontal line with several parallel vertical lines extending downwards from it. Within this simple pattern, however, the comb motifs can be divided into simple and complex forms. Three of the motifs examined, UT3- M48, UT5- S4- M7, and UT3- M37, were of the simple type, while the fourth, UT5-S2-M19, was of the complex form. All of the comb motifs are executed in a reddish black pigment. Most are isolated from other artworks, although one (UT5-S2-M19) is part of a complex series of superimposed images from different periods. 

Dated rock art paintings from Cueva Huenul 1. (A) Motif Ut3- M37. (B) Motif Ut3- M48. (C) Motif Ut5- S4- M7. Guadalupe Romero Villanueva in Villanueva et al. (2024).

By careful examination of the motifs, Villanueva et al. were able to establish that there was no potentially contaminating organic matter  either  on,  within,  or  below  the  paint  layer. Three layers were found to be present, the bedrock, the pigment layer, and an overlying layer of translucent particles forming a patina. The pigment layer was identified spectrographically as amorphous carbon; this was found not to contain any significant amount of phosphates, making it unlikely it was derived from carbonized bone.

Dated rock art motif UT5- S2- M19 from Cueva Huenul 1. (A) Original photograph and digital enhancement with DStretch of the complete rock art panel. (B) Original photograph and digital enhancement with DStretch of the dated black comb-shaped motif. (C) digital tracing of the complete rock art panel showing the dated black comb-shaped motif underlaying a series of superimpositions. Guadalupe Romero Villanueva in Villanueva et al. (2024).

Further examination of the samples by Scanning Electron Microscopy and Energy Dispersive X-Ray Analysis demonstrated the presence of plant cells within the pigment layer of all four examined motifs, as well as a composition consistent with a carbonaceous material mixed into an aluminosilicate matrix (i.e. a mixture of charcoal and clay), with the overlying layer of material rich in calcium and sulphur, probably indicating some form of salt. The precise origin of the wood used to make the charcoal was impossible to determine, although it is likely to have been one of the woody shrubs known to have been growing in the region in the Middle Holocene, such as Prosopis spp., Larrea sp., or Schinus sp..

Cross section microphotography of sample CH1-AMS1 embedded in resin showing three differentiated layers. From the bottom, the layers which can be distinguished are; the bedrock support, the black pictorial layer, and a thin layer of patina or varnish. Marcela Sepúlveda and Guadalupe Romero Villanueva in Villanueva et al. (2024).

Based upon this, Villanueva et al. conclude that the black pigment was formed by the incomplete burning of Plant matter, something which should lead a carbon¹⁴ signature. Since there are no long-lived trees in the region, material from which can give misleading date information, the charcoal can be assumed to have come from a short-lived woody C₃ shrub and/or a Cactus (which have their own Crassulacean acid metabolism resulting in a distinctive carbon isotope signature). It was possible to recover sufficient carbon from three of the motifs to be confident that the isotope signature recovered was accurate, while one sample, taken from motif UT5-S2-M19, yielded a much lower amount of carbon, raising concerns that contamination from later sources (this is the motif which is partially overlain by later artworks), leading to this data being excluded from the remainder of the study. The remaining three motifs were found to be between 7728 and 7565 years old (UT3- M48), between 6271 and 6239 years old (UT5- S4- M7), and between 5643 and 5629 years old (UT3- M37).

As well as the dates obtained for the rock art motifs, Villanueva et al. obtained 16 dates from archaeological remains at the site, in order to build up a stratigraphic sequence. This led them to conclude that there had been four stages of occupation at the site, over a period of about 18 000 years. 

The first phase is calculated to have lasted approximately 4683 years, from about 17 407 to about 12 934 years before the present. During this phase the cave was occupied by Giant Sloths, with no signs of Human activity. 

The second phase is calculated to have lasted approximately 1620 years, from about 11 721 to about 10 162 years before the present, and shows evidence of the first Human activity in the area, including Guanaco bones with cut marks, hearths with charcoal, and a grass bedding structure. 

There is then a significant hiatus in activity, with the third phase starting about 8171 years ago and lasting for approximately 3246 years, till about 5074 years before the present. This phase includes the emergence of rock art at the site, with all three dates obtained for the comb motifs falling within this interval, as well as the ochre covered Plant remains. Assuming that the average Human generation time was about 25 years, this would suggest a cultural tradition using similar symbolism which lasted for about 130 generations. 

The final phase of activity at the cave includes much more intensive activity, includuing the majority of the rock art, as well as cultural similarities to other sites in the region, and spans about 1500 years in the Late Holocene.

Climatically, the area had a sharper east-west variation in moisture during the Late Pleistocene and Early Holocene, until about 10 000 years ago, with the western Andes being wetter than today, while the eastern Andes were drier. The region to the east of the Andes, inclding the Cueva Huenul 1 site, was significantly more arid than today between about 10 400 and 9 400 years ago. From about 10 000 years ago onwards both the Andes and Eastern Patagonia became extremely arid.

The area reached peak aridity in the Middle Holocene, with widespread deserts and only patchy, fragmented areas of habitable land, which could have acted as stepping stones for the first Humans entering the environment. Large areas would have either too dry for occupation, or too unstable to be entered on more than a temporary basis. Nevertheless, Humans did enter the landscape during this time, probably relocating frequently, and needing to maintain social contact over large distances, while at the same time coming up with innovative technologies for subsistence.

By assembling a comprehensive database of radiocarbon dates for Human activity across the South American Arid Diagonal region, Villanueva et al. conclude that during the period 14 000 to 10 400 years before present the first Human population appeared and rapidly grew, expanding to occupy new niches. From about 10 800 to 7000 years ago a period of cultural stasis appeared, combined with a slowly declining population. The oldest rock art at Cueva Huenul 1 is slightly less that 8000 years old, coinciding with the later part of this period of apparent cultural stasis. The population is also thought to have remained fairly static or shrank across South America between about 9000 and about 5500 years ago. 

This suggests that during the Middle Holocene northwestern Patagonia was probably home to a small and scattered population of highly mobile hunter-gatherers, coping with an extremely arid climate with occasional wetter spells. This population was static or shrinking slightly, widely scattered, and having to cope with frequent but unpredictable extreme weather conditions.

The dating of the comb motifs in the rock art of Cueva Huenul 1 gives a date for the origins of rock art in northwestern Patagonia. The repeated nature of these motifs makes it unlikely that these marks were random, with similar marks being repeated several times over a period of about 3000 years, suggesting it was linked to a system for passing information between generations.

Transmission of knowledge can become linked to particular sites, which eventually become key locations for a culture, where people meet to re-enforce cultural identities and maintain extended social networks. Villanueva et al.  suggest that Cueva Huenul 1 first became such a culturally important site during the Late Pleistocene, being used regularly over a period of about 1400 years across the End Pleistocene and Early Holocene. Visits to the site continued into the Middle Holocene, though the behaviour of the visitors changed, with the appearance of activities such as marking the walls. During this phase, there is little sign of non-ritual activities, such as food-processing or tool-making. Villanueva et al. suggest that the transition of the space to a ritual centre where these profane activities were not carried out probably implies that the site was not, as previously assumed, abandoned for long periods during the Middle Holocene, but rather underwent a change of purpose connected to its new, sacred status. 

Villanueva et al. suggest the emergence of sites such as Cueva Huenul 1 which helped hold widely scattered cultures together would have been key to Human survival in the arid landscape of northwestern Patagonia. The emergence or rock art was probably a way of re-enforcing knowledge transfer across generations, building upon an earlier oral tradition. 

The population of many areas in South America apparently struggled to cope with conditions in the Middle Holocene, as increasing aridity fragmented the available liveable spaces, leading to a slowly dwindling population. The first rock art at Cueva Huenul 1 coincides with this period, possibly aiding social cohesion and helping  people to survive a particularly harsh period, before populations began to recover between 7000 and 5000 years ago. 

The dating of the rock art at Cueva Huenul 1 gives an insight into the context in which such art first appeared in Patagonia. Here, a style of art appears around 8000 years ago and persists for over 3000 years. This happened at a time when the climate was much drier and less predictable than today, at a time when Human populations were at best maintaining stasis, and were probably suffering frequent crashes. It this marginal, sparsely populated environment the rock art apparently helped to preserve collective knowledge across multiple generations. 

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Monday 19 February 2024

Investigating Crocodile attacks around Roviana Lagoon, New Georgia, the Solomon Islands.

Saltwater Crocodiles, Crocodylus porosus, are found in coastal environments in the Asia-Pacific region from the Bay of Bengal, throughout Southeast Asia and New Guinea, to northern Australia, and as far east as the Solomon Islands. Unlike other Crocodile species, they are not currently considered to be threatened, being classified as of Least Concern under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. However, this assessment is essentially dependent on good relations between Human and Crocodile populations; Saltwater Crocodiles will attack Humans and livestock, causing injuries and deaths, as well as less obvious economic damage by excluding Humans from areas where they become dangerous. This in turn can lead to retaliatory actions by Humans, removing troublesome Crocodiles, or sometimes whole populations, from areas where they are seen as harmful. 

Saltwater Crocodiles feed in tidal rivers and creeks, freshwater lakes and Mangrove forests, and will occasionally forage on Coral reefs. While they cross open sea to seek new territory, they do not usually hunt or feed there. Female Saltwater Crocodiles can reach about 3 m in length, and can weigh as much as 150 kg, but the largest males can reach more than 6 m in length and weigh more than 1000 kg. Males will try to defend a territory and the females within it, chasing away smaller males, who then go on to look for territories of their own, which can lead to changes in the social structure and behaviour of Crocodile groups.

In a paper published in the journal Orynx on 22 January 2024, Shankar Aswani of Rhodes University and Joshua Matazima of the University of Queensland present the results of a study of negative Human-Crocodile interactions around Roviana Lagoon on the island of New Georgia in the Solomon Islands.

A previous study examined Human-Crocodile interactions across the Solomon Islands over the period 1998-2017. This study identified 225 Crocodile attacks across the islands, with 83 of these being fatal, including 31 on children. Aswani and Matazima's study concentrates on a much smaller area, and is aimed at understanding Human-Crocodile interactions in a specific, localised environment with a view to developing specific policies for that location, something which it is difficult to achieve from wider scale national surveys.

Aswani and Matazima's study concentrated on four villages, Dunde, Baraulu, Nusa Hope, and Kozou, located on the 700 km² Roviana Lagoon, on the southwest of New Georgia island. Each village has a population of between 50 and 300 people. Twenty three men and thirty seven women from sixty households across the four villages were interviewed by three locally hired assistants, in the local Roviana language. Twenty of the interviewees reported that a member of their household being attacked by a Crocodile between 2000 and 2020, four in Dunde, seven in Baraulu, five in Nusa Hope and four in Kozou.

Locations of the four villages (Dunde, Baraulu, Nusa Hope and Kozou) in which residents were interviewed regarding incidents with Saltwater Srocodiles, Crocodylus porosus, in  Roviana Lagoon, New Georgia Group, western Solomon Islands, during 2000-2020. Aswani & Matazima (2024).

A total of twenty attacks were recalled, of which two were fatal. Ten of the recalled incidents happened in the evening, eight in the afternoon, and two in the morning. Sixteen victims were female, and four were male; one woman and one man were killed during the study period. Two were under twenty years of age, eight were between 20 and 39, two were 40-59, and eight were over sixty years of age. The majority of the victims were attacked while collecting shellfish along the sea shore and in Mangrove forests. Ten of the victims were attacked when the water was murky, with the other ten attacked when the water was clear. No retaliatory attacks were made against Crocodiles be the people of the area.

The pattern of attacks recorded in Roviana Lagoon were quite different to that recorded in the Solomon Islands-wide survey, although it may be similar to other localised areas within the nation. Across the Solomons, the majority of the victims were male, attacked at night while fishing, while in Roviana Lagoon the majority of the victims were female, attacked in the afternoon or early evening while gathering shellfish. Clearly, any system developed to minimize the number of Crocodile attacks based upon the national statistics would have little impact at Roviana Lagoon, since such a plan would likely concentrate on protecting men involved in night-fishing, an activity not practiced in Roviana Lagoon. Even a female specific plan developed from national statistics would be unlikely to be helpful, as across the Solomon Islands the majority of women are attacked while washing clothes.

Shellfish gathering, both for sustenance and sale, is an important activity to the women of Roviana Lagoon, but clearly leaves them vulnerable to attacks by Crocodiles. This activity is carried out almost exclusively by women, although they are frequently accompanied by children of both sexes. Most of the attacks happened in late afternoon or early evening, and water clarity did not appear to be a factor, possibly because the low sun shining onto clear water can make submerged Crocodiles just as hard to spot as the water being cloudy. 

Aswani and Matazima recommend that in order to minimise the number of Crocodile attacks, the women of Roviana Lagoon avoid collecting shellfish in the late afternoon and evening as much as possible, and that where this cannot be avoided, always forage in groups at this time of day, which will both improve the chances of spotting Crocodiles before attacks occur, and of rescuing any victims should attacks occur. They further recommend that future studies of Crocodile attacks focus on much narrower geographic areas when the purpose is to develop strategies to minimise attacks.

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Sunday 18 February 2024

Understanding the orientation of graves in the Bronze Age Gumugou Cemetery of Xinjiang Province, China.

Many cultures bury their dead with a preferred orientation, and understanding how this is chosen can tell us a great deal about the beliefs of a culture. The orientation of graves has been extensively studied for ancient European and Mediterranean cultures, demonstrating that burials were often aligned with both terrestrial and celestial objects of importance by ancient peoples, but has been less well studied in other parts of the world.

In a paper published in the Journal of Archaeological Science: Reports on 17 February 2024, Jingjing Li of the Xinjiang Astronomical Observatory, Jarken Esimbek, also of the Xinjiang Astronomical Observatory, and of the University of the Chinese Academy of Sciences, and Yingxiu Ma, again of the Xinjiang Astronomical Observatory, examine the orientation of graves in the Bronze Age Gumugou Cemetery of Xinjiang Province, China.

The Gumugou Cemetery is located on the eastern fringe of the Taklimakan Desert, in the Tarim Basin, to the north of the now dry Kongque (Peacock) River and about 70 km to the west of the Lop Nor Salt Lake. The cemetery has been dated to between 3800 and 3400 years before the present, and along with a series of related sites within the region between Lop Nor and the Taklimakan Desert, is considered representative of one of the oldest known Bronze Age cultures within Xinjiang Province.

Location of the Gumugou Cemetery and other archaeology sites in the Tarim Basin, Xinjiang. Li et al. (2024).

The Gumugou Cemetery site was excavated in the winter of 1979 by an expedition from the Xinjiang Institute of Archaeology under the leadership of Binghua Wang. A total of 42 burials were discovered and excavated, all within an area of 1600 m³. The burials could be divided into two types, with six Type I burials forming an upper layer, and 36 Type II burials forming a lower layer. 

The Type I burials are quite often placed above Type II burials, and are surrounded by seven rounds of timber posts. These Type I burials apparently contained wooded coffins, which have long decayed away, leaving the (well preserved) Human remains exposed. A small amount of grave goods were present. 

Surface of Type I burials of the Gumugou site. Li et al. (2024).

Type II burials form a lower layer and each contain a single body placed within a boat-shaped coffin between two posts, one at the head of the coffin and one at the feet. These contained more numerous grave goods, including pointed felt hats, leather, woollen capes, grass woven baskets, bone and stone artifacts, wheat grains, and Ephedra twigs. While grave goods were more numerous in the Type II burials than the Type I burials, there was otherwise little to differentiate them, and they are presumed to have come from the same culture.

Part of Type II burials of Gumugou Cemetery. Binghua Wang in Li et al. (2024).

The tombs are aligned roughly along an east-west axis, with their heads to the east, which, combined with the posts surrounding the Type I burials, which resemble solar rays, was taken as evidence of sun-worship by the people who used the cemetery.

However, Wang took care to record every detail about the graves, including the azimuth of each burial (the azimuth is an orientation relative to true north, where north is 0°, east is 90°, south is 180°, etc.). Li et al. collated this data, and compared it to a calculated solar arc for sunrises at the site. A solar arc of sunrises is made up of the azimuth of the sunrise throughout the year, giving an arc (in the Northern Hemisphere) with the Summer Solstice to the north and the Winter Solstice to the south. At the Gumugou Cemetery the sunrise azimuth is 57.7° on the summer solstice and 120.8° on the winter solstice, while the graves have azimuths of between 102° and 58°.

Orientations of the grave in Gumugou cemetery. Li et al. (2024).

The region where the Gumugou Cemetery is located has an arid desert climate with temperatures reaching as high as 40°C in the summer and falling as low as -20°C in the winter, and strong winds in spring and autumn leading to dust storms which can cause potentially lethal respiratory illnesses. The graves in the cemetery contain men and women, adults and children, with no apparent connection between age and/or gender of the occupant and the type of burial, the amount of grave goods, or the orientation of the grave. 

The graves vary in orientation, but are clustered around azimuth directions of 90° and slightly north of this. If the graves were orientated in line with the orientation of the sun at the time of burial, as Li et al. suspect, then the overwhelming majority of the dead would have been buried at or around the Spring and/or Autumn Equinoxes. Since it is unlikely that people were only dying at these times of year, Li et al. instead suggest that the graves represent secondary burials, with the dead being stored elsewhere until the favoured season of funerals.

Histogram of aligned skeletons. Li et al. (2024).

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Saturday 17 February 2024

A possible crown-group Bird from the Late Cretaceous Lance Formation of Wyoming.

The origins and evolution of Mesozoic Birds are now well understood, but the emergence and development of the crown group Birds (a crown group contains all living members of a group, their most recent common ancestor, and everything descended from that ancestor) remains largely clouded in mystery. Most living Bird groups have a very poor fossil record, if they have a fossil record at all, despite Birds being the most diverse group of flying Vertebrates alive today, with more than 10 000 species. Fossils, where known, tend to be extremely fragmentary in nature, with most phylogenies of the group based entirely upon genetic data. This is particularly frustrating as the living Birds are the only group of Dinosaurs to have survived the End Cretaceous Extinction, something which has been taken to imply they had some quality missing in all other Avian and non-Avian Dinosaur groups. However, while crown group Birds are known to arisen before the End of the Cretaceous, they appear to have been at best a minor component of the Cretaceous Fauna, with few-or-no specimens found even in deposits which have produced numerous fossils of extinct Mesozoic Bird groups.

In a paper published in the journal BMC Ecology and Evolution on 9 February 2024, Chase Doran Brownstein of the Department of Ecology and Evolutionary Biology at Yale University and the Stamford Museum and Nature Center, describes a possible crown group Bird from the End Cretaceous Lance Formation of Wyoming.

The specimen, YPM VP 59473, comprises partial skeleton consisting of the complete left quadrate, portions of the skull roof a partially articulated, though very poorly preserved, cervical series, a fragment of the synsacrum, the left humerus, the articulated left radius and ulna, partial left tibiotarsus, and a partial pes. The material is largely disarticulated, but all of the bones are from a young juvenile and no duplicate bones are present, supporting the idea that they came from a single Animal.

Preservation of YPM VP 59473. The blocks containing all bones of the holotype (except for the humerus, tibiotarsus, synsacrum fragment, and large distal pedal phalanx) are shown under light microscopy (a), (e), (h) and with multiple x-ray views of the largest (b), (c), (d), second largest (f), (g), and smallest (i) blocks as rendered in VGStudio, showing the relative placement of bones in the matrix blocks. Brownstein (2024).

Despite the extremely fragmentary nature of the material, Brownstein feels confident in assigning the specimen to the Galloanserae, the group which includes the living Land and Water Fowl, and one of the three groups of Neornithine Birds thought to have diverged before the End of the Cretaceous, with the Palaeognaths and the Neoaves. This diagnosis is on the basis of the clear separation of the otic and squamosal capitula on the quadrate, the presence of a subcapitular tuberculum below the squamosal capitulum on the quadrate, the expansion of the ventral condyles and pterygoid condyle on the quadrate, the humeral head being dorsally offset from the rest of the proximal margin of the humerus, tricipital fossa being deeply excavated, and the dorsal tubercle of the humerus being large and offset from the rest of the proximal margin, all of which traits are typical of Galloanserine Birds, but absent in the various Mesozoic Avian stem groups.

Forelimb of YPM VP 59473. Humerus in (a) posterior, (b) anterior, (c) lateral, and (d) medial views. In (a) and (b), both CT scans and colour images are shown. Radius in (e) anterior, (f) posterior, (g) lateral, (h) medial, and (i) distal views. Ulna in (j) posterior, (k) anterior, (l) lateral, and (m) medial views. Brownstein (2024).

While the presence of a Galloanserine Bird in an End Cretaceous deposit is not unexpected, the presence of the specimen in the Lance Formation is significant in two ways. 

Firstly, because the deposit is from the Northern Hemisphere; phylogenetic studies of Birds based upon genetic data have found that the earliest diverging members of many groups have Southern Hemisphere distributions, which has led to speculation that the Neornithine Birds might have had a Southern Hemisphere origin, and the establishment of YPM VP 59473 adds to a growing body of data which contradicts that, suggesting that Neornithine Birds already had a global distribution in the Late Mesozoic. 

Secondly, unlike other deposits which have yielded Mesozoic Neornithine Birds, the fossils of the Lance Formation are thought to have been buried in situ, rather than being an accumulation deposit. This is important because the deposit has also produced toothed stem-Birds from at least four major clades, as well as Eudromaeosaurian, Alvarezsaurid, Troodontid, and potentially ‘four-winged’ Microraptorine Dinosaurs, all of which are thought to have been ecologically close to Birds. This is significant, as it suggests that the Neornithine Birds were not occupying some ecological niche which protected them from the impacts of the End Cretaceous Extinction, but instead were part of a community of ecologically similar Animals living in similar environments. This undermines the idea that Neornithine Birds were able to survive the End Cretaceous Extinction because they were in some way special, supporting the alternative hypothesis that they survived due to simple luck an important but sometimes overlooked factor in evolutionary biology.

The ecological and temporal origins of living Birds. Left side of the diagram shows the temporal and spatial range extensions and records of key small-bodied non-Avian Theropod clades found in the Lance Formation assemblage, and cladogram at right shows the major clades of stem and crown Birds that survive to or past the End  Cretaceous extinction, with ecologically relevant features that have been considered important to differential Avian survival through that event noted along branches. All clades shown on tree are unambiguously represented in the Lance Formation assemblage, except Neoaves and Paleognathae. Bird illustrations by John Gould. Brownstein (2024).

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Rescue workers in Turkey search for mineworkers trapped beneath landslide.

Hundreds of rescue workers have been deployed to a mine in eastern Turkey following a landslide on Tuesday 13 February 2024. The event happened when a spoil heap from the open-pit gold mine collapsed, leading several hundred tonnes of cyanide-laced soil to flow down into the mine site. Nine workers are reported to still be trapped within the mine, five within a shipping container, one inside a truck, and three in another vehicle. Concerns have been raised that cyanide from the mine may enter the Euphrates River, which runs close to the mine in the İliç District of Erzincan Province, then though Syria and Iraq before entering the Persian Gulf. Authorities in Turkey report damming a stream which flows from the mine to the Euphrates, and carrying out ongoing monitoring of the river.

Military personnel near the site of a gold mine hit by a landslide in Erzincan, Turkey. Ugur Yildirim/Getty Images.

The incident happened at the Çöpler Mine, which is operated by Anagold Madencilik, a subsidiary of the American SSR Mining. The mine has previously faced calls for its closure over an apparently poor safety record, following a cyanide leak in 2020, when the Euphrates was affected. On that occasion the mine was fined 16.5 million Turkish lire (US$537 000), but allowed to resume operating in 2022, despite objections from a range of organisations, including the Union of Chambers of Turkish Engineers and Architects, which includes the Chamber of Mining Engineers. Operations at the mine have been suspended pending an investigation. Four members of staff, including the pit's field manager, have been arrested as part of the investigation.

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