Australia: The Land Where Time Began
Neanderthal in the Karst – The Fossil Skeleton from Altamura (Italy), First Dating, Morphometric and Palaeogenetic Data
A fossil skeleton was found in the karst caves of Lamalunga, near Altamura, southern Italy in 1993. Over the last 2 decades knowledge of it has been based purely on the documented on-site observations, in spite of this specimen representing one of the most extraordinary hominin specimens that has ever been found in Europe. The recent retrieval of a fragment of bone (part of the right scapula) from the cave allowed the first dating of the individual, the quantitative analysis of a diagnostic morphological feature, and a preliminary palaeogenetic characterisation of this hominin skeleton from Altamura. The results concur, overall, in indicating that it belongs to the hypodigm of Home neanderthalensis, though there are some phenetic peculiarities that are apparently consistent with a chronology that ranges from 172 ± 15 ka to 130.1 ± 1.9 ka. The skeleton from Altamura represents, therefore, the most ancient Neanderthal from which endogenous DNA has ever been extracted.
In the limestone of the Murgia Plateau, at an elevation of 508 m above sea level (ASL), is the opening of the Lamalunga Cave, near the town of Altamura (Puglia, Italy; Agostini, 2011). It constitutes the upper part of a much larger karst complex where stalactites, stalagmites and flowstones occur, together with “coralloid” formations, which mostly represent the last phase of calcite precipitation that results from spray/aerosol phenomena. The complex mainly consists of a sub-horizontal gallery that had developed at a shallow depth from the surface, intercepted by pits that had originally opened to the surface, than were subsequently clogged by detritus. The discovery in this context, of a virtually complete fossilised hominin skeleton in an excellent state of preservation leads to interesting taphonomic considerations. Particularly, faunal remains that were found in some of the galleries are often bony elements that are isolated, which accumulated in depressed areas of the cave, which suggests that they were transported and dispersed by water. In the case of the human skeleton, this was not the case, as it is largely represented and concentrated in a small area. Lari et al. therefore hypothesised that following death and decomposition of the body, the skeleton collapsed where it had been found. To date, no lithic tools have been found in the cave.
Most of the bones are visible (see Supporting Online Material [SOM] Fig. 1), including the cranium, which is upside down, the mandible and several postcranial elements, though the skeleton is partially incorporated into the calcite concretions and is covered by coralloid formations. The skeleton appears to exhibit a mixture of archaic and derived features, which fits the range of variations that are typical of European hominins of the late Middle/early Late Pleistocene (Manzi et al., 2011), based on available photographs and direct observations that were made in situ by one of the team (GM). There are features that distinguish this specimen from the more typical morphology of Homo neanderthalensis, such as the shape of the brow ridges, relative dimensions of the mastoids, and the general architecture of the cranial vault, even though, in fact, a number of Neanderthal traits can be seen, in particular, in the face and in the occipital bone. Nevertheless, the only information on this extraordinary fossil skeleton that was available for many years was based on preliminary on-site photographs and observations (Pesce, Delfino & Vacca, 1993), which were biased by the presence of calcite formations. A more recent survey in the cave as part of a new project that was commissioned by the local authorities, that was aimed at carefully removing an isolated skeletal fragment. Subsequently, in February 2011, other samples were taken, which included calcite material that was suitable for U/Th daring.
For the first time, therefore, it is possible to report quantitative data for the skeleton from Altamura, which included its first dating, the morphometric analysis of its post-cranial morphology, (part of the right scapula, and a preliminary palaeogenetic characterisation.
The skeleton that was recovered from Altamura was in an excellent state of preservation with almost every bone being part of a single adult individual that was preserved in the rather small space where it was found. All the bones were found, in fact, at the end of a narrow corridor which is known as the “ramo dell’uomo” (“branch of man”) and generally appear to not have been damaged or distorted, except for a few elements that were identified in a smaller chamber behind the area where the same assemblage was found.
Lari et al. obtained permission to remove a piece of bone from the Lamalunga skeleton in May 2009. They chose a bone from the smaller chamber behind the skeleton for several reasons:
1. In order to obtain a bone with minimum contamination, in view pf the palaeogenetic investigations to be carried out;
2. To avoid interfering directly with the main assemblage of bones before a full and thorough 3D laser survey could be performed; and
3. To avoid bones with extensive calcite concretions.
Therefore, with the help of speleologists of the Centro Altamurano Richerche Speleologiche (CARS) of Altamura the sample was recovered by one of the team (MM) in July 2009, following sterile collection procedures and according to a procedure that was inspired by laparoscopic surgery.
The sample consists of the articular portion of the right scapula, in which the glenoid fossa, the neck and part of the spine (without the acromion), and the root of the coracoid process were preserved. It was free from major concretion, apart from a superficial film of calcite, in contrast to most of the bones of the main assemblage. The scapula was fractured in 2 main parts when it was discovered – the articular portion that was extracted and a large part of the body that was visible on the floor of the cave – while also present were small fragments that were scattered in an area of about 40 cm2. It was reasonable to infer that the scapula was part of the main assemblage of the skeleton, as only various bony elements that belonged to a single individual are documented in the cave and that the right scapula is missing from the inventory of the bones in the main assemblage; moreover, the humerus of the same side is visible in the small chamber behind the skeleton.
Following extraction, the specimen was kept in sterile conditions and submitted to professional photographic documentation and medical tomography.
Dating the scapula
Immediately following its recovery in 2009 the first attempt was made to date the scapula directly with AMS 14C. 3 separate fragments of the Centro di Datazione e Diagnostica (CEDAD) of the University of Salento, Lecce were used for this analysis. However the collagen extraction was made ineffectual by the pervasive overgrowth of the calcite within and around the fragments and insufficient C was recovered to perform a proper analysis (Lucio Calcagnile, pers. Comm.).
Subsequently, additional sampling was carried out in order to in February 2011when 4 calcite specimens that had directly covered the hominin bones were carefully removed along with a small stalagmite, which was naturally broken, encrusted with a thick coralloid overgrowth. Ultrasonic processes were used to clean the samples, embedded in resin, and sliced along the axial growth direction. Several phases of growth of the coralloid overgrowth were revealed by optical microscopy observation of the samples, which enabled the selection of 3 of the best samples for U/Th dating. These were:
1) A thin calcite crust that coated the underside of the long bone (ABS2, fibula);
2) A coralloid overgrowth that was 5 mm thick covering the end of a short bone (ABS3); and
3) A coralloid overgrowth that was 10 mm thick covered the naturally broken stalagmite (ABS5).
A Multicollector Ion Coupled Plasma Mass Spectrometer (MC-ICP-MS) was used to conduct the U/Th analyses at the Laboratory of Isotope Chemistry, University of Melbourne). The analytical procedures for chemical preparation and subsequent analysis by mass spectrometry are described by Hellstrom (2003).
The overall results of the morphometric and palaeogenetic analysis concur, indicating the skeleton from Altamura is from a Neanderthal. Also, dating using U/Th it was possible to provide the first range of dates for the specimen, between 130 ± 2 ka and 172 ± 15 ka.
Some features that were, nevertheless, exhibited by the skeleton and observed in situ (on the cranium, in particular, as was summarised in the introduction) differ from the known morphology among the typical representatives of H. neanderthalensis, though they appear to be consistent with the pre-Wũrmian age that was observed. It is shown by the metrical variables that the scapula-humeral joint is closer to the morphotypes that are usually referred to the so-called “early Neanderthals,” which included specimens such as those from Saccopastore (e.g., Bruner & Manzi, 2006), Krapina (e.g., Monge et al., 2008) or Apidima (Havarti et al., 2011). Also, it is suggested by morphometric analysis of the SGF from Altamura that some peculiarities of this small piece of bone, While (consistent with the mtDNA data), the same analysis strengthens the suggestion that the morphology of the Neanderthal was essentially present in the Middle Pleistocene.
According to Lari et al. it is of great interest that mtDNA was preserved sufficiently well to allow palaeogenetic analysis. It has been shown by the results of the explorative approach that was used in this study that the sample contained endogenous DNA (though highly fragmented) with a typical Neanderthal haplotype; there was, moreover, no evidence of modern human contamination in the fragment of bone, at least not at the mtDNA level. According to Lari et al. the Altamura skeleton should be considered to be a good candidate, for three reasons, for genomic analyses that are more innovative, such as capture approaches or ultra-deep shotgun sequencing, especially when it is considered that Altamura represents the most ancient Neanderthal from which endogenous DNA has been retrieved so far.
Lari, M., et al. (2015). "The Neanderthal in the karst: First dating, morphometric, and paleogenetic data on the fossil skeleton from Altamura (Italy)." Journal of Human Evolution 82(0): 88-94.
|Author: M.H.Monroe Email: email@example.com Sources & Further reading|