The language capability of Neanderthal man

Considerable publicity has been given a recent article by Lieberman and Crelin ('71) which argues that Neanderthal man lacked the physical features necessary for speech. This present paper presents statistics on some modern men with normal speech who show physical features in common with Neanderthal man. The brain of Neanderthal man was as large as, or larger than, that of modern man. The brain reflected by the endocranial cast of the La Chapelle-aux-Saints skull resembles that of modern man in an area important for speech and thereby suggests Neanderthal man had the neural development necessary for language.     

Approche paléontologique de l’évolution du langage : un état des lieux

One of the most influential paleoanthropological approaches to the question of language origins has been the attempt to reconstruct the supralaryngeal vocal tract (SVT) in fossil humans. In particular, the low placement of the larynx was considered to be a uniquely human feature and was interpreted as a specific adaptation to produce human speech. Nevertheless, based on the anatomy of the basicranium and the hyoid bone, various researchers reached different conclusions regarding the placement of the larynx in human fossils, especially in Neandertals. Further, the recent finding of a low placement of the larynx in chimpanzees, calls into question the basic premise on which much of this research has been based. To overcome this, we have proposed and developed a new line of research into the question of speech capabilities in fossil specimens which is focused not on the ability to produce the sounds of spoken language, but on the capacity to perceive them. The modern human auditory pattern is unique among primates in showing a relatively heightened sensitivity to the midrange frequencies between 2-4 kHz, a frequency range which coincides with that of spoken language. Our analysis shows that the preserved skeletal anatomy of the outer and middle ear in the Middle Pleistocene hominids from the site of the Sima de los Huesos is compatible with human-like auditory capacities, and is clearly different from chimpanzees in the midrange frequencies. These results strongly suggest that the anatomical structures which support the modern hum and pattern of intraspecific communication were already present in these human ancestors. Further, the presence of a common condition in both the modern human and Neandertal evolutionary lineages suggests this represents an ancient adaptation within the genus Homo.     

The deduction of the level of the human larynx from bony landmarks: Its relevance to the evolutionos speech

It has been claimed that the capacity for speech in hominids is related to the level of the larynx relative to its surrounding structures. Lower positioned larynges, such as those found in modern humans, have been said to be a prerequisite for articulate speech. In certain fossil hominids, the level of the larynx has been deduced from the angulation of the styloid process and the distance from the posterior nasal spine to the basion (the distance PB). The hypothesis that correlations exist between these bony features and the level of the larynx was tested in this study. The inclination of the styloid process and the level of the larynx were measured on human cadavers and on lateral x-ray cephalograms of the same cadavers. In addition, the distance PB and the level of the larynx were measured on lateral cephalograms of living adult humans. The inclination of the styloid process and the distance PB were also measured on a series of adult dry skulls. Pearson's correlation coefficients for the three sets of measurements were calculated. Only slight correlations between the inclination of the styloid process, the distance PB, and the level the larynx were found. The results of this study indicate that accurate prediction of the level of the larynx from the inclination of the styloid process and the distance PB is not possible.     

Neandertal Demise: An Archaeological Analysis of the Modern Human Superiority Complex

Neandertals are the best-studied of all extinct hominins, with a rich fossil record sampling hundreds of individuals, roughly dating from between 350,000 and 40,000 years ago. Their distinct fossil remains have been retrieved from Portugal in the west to the Altai area in central Asia in the east and from below the waters of the North Sea in the north to a series of caves in Israel in the south. Having thrived in Eurasia for more than 300,000 years, Neandertals vanished from the record around 40,000 years ago, when modern humans entered Europe. Modern humans are usually seen as superior in a wide range of domains, including weaponry and subsistence strategies, which would have led to the demise of Neandertals. This systematic review of the archaeological records of Neandertals and their modern human contemporaries finds no support for such interpretations, as the Neandertal archaeological record is not different enough to explain the demise in terms of inferiority in archaeologically visible domains. Instead, current genetic data suggest that complex processes of interbreeding and assimilation may have been responsible for the disappearance of the specific Neandertal morphology from the fossil record.     

Human hyoid bones from the middle Pleistocene site of the Sima de los Huesos (Sierra de Atapuerca, Spain)

This study describes and compares two hyoid bones from the middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca (Spain). The Atapuerca SH hyoids are humanlike in both their morphology and dimensions, and they clearly differ from the hyoid bones of chimpanzees and Australopithecus afarensis. Their comparison with the Neandertal specimens Kebara 2 and SDR-034 makes it possible to begin to approach the question of temporal variation and sexual dimorphism in this bone in fossil humans. The results presented here show that the degree of metric and anatomical variation in the fossil sample was similar in magnitude and kind to living humans. Modern hyoid morphology was present by at least 530 kya and appears to represent a shared derived feature of the modern human and Neandertal evolutionary lineages inherited from their last common ancestor.     

Absolute and relative endocranial size in Neandertals and later Pleistocene Homo

Eurasian Neandertals encompass the entire observed range of recent and fossil Homo sapiens in absolute, but not relative endocranial volume, and Neandertals attest an average EQ significantly lower than their Upper Pleistocene successors. While the cognitive, social, and evolutionary implications of this phenomenon have been emphasised, the statistical basis of a mean inference of EQ in the Neandertal hypodigm has not been appropriately demonstrated. A demonstrable male bias in the available postcranial, not cranial, series has skewed perceptions of Neandertal brain-to-body size scaling towards a rejection of the null hypothesis. A simple resolution to this problem is a concise assessment of paired associated covariates against a suitable recent human comparator series. Permutations of Fisher's z and Student's t statistics are valid metrics in tests of significance in single datum hypotheses.     

Morphometrics of the Neandertal talus.

A number of morphometric analyses of Neandertal tali since the turn of the century have failed to reach a consensus on the functional affinities of these fossil foot bones. To clarify the problem a univariate and multivariate analysis of the available Neandertal and Skhūl tali in relation to those of modern humans was performed using nine linear dimensions and four angles. Our analysis indicates that Neandertal tali are indistinguishable from modern human tali in the implied locomotor capabilities and similar in overall size and proportions. The primary differences between the fossil and modern tali involve the greater articular robustness of the fossils, probably to compensate for higher levels of biomechanical stress.     

Virtual reconstruction of the Neandertal lower limbs with an estimation of hamstring muscle moment arms

A major problem of fossil hominid analysis is a lack of complete specimens. Many individual specimens have been damaged by the effects of diagenesis and excavation. Significant advances in the field of three dimensional image processing (3D) have enabled the creation of accurately scaled reconstructions of individual fossil bones using mirrored parts of the same fossil bone or human/fossil hominid equivalents. This study presents, for the first time, a method to reconstruct a 3D virtual model of the lower limb of the Neandertal using different bones from different fossil remains (Spy II, Neandertal 1 and Kebara 2) and integrating them into a single model of the Neandertal lower limb. A biomechanical analysis of the model was performed, including computer graphics visualization of the results, motion displacement graphs and muscle moment arms. The overall method has been implemented into an open-source customized software (lhpFusionBox) developed for the biomechanical study of the musculoskeletal system.     

The premaxilla in Neandertal and early modern children: ontogeny and morphology.

This comparative study of maxillae in Neandertals, Qafzeh, and extant children examines two specific traits: the premaxillary suture (sutura incisiva) and the interincisive sinuses, proposing a new hypothesis about some features of the Neandertal mid-face. Morphologic study of the premaxillary suture at its different borders (i.e. the nasal aspect of the frontal process, nasal and palatal aspects of the palatal process of the maxilla) indicates a persistence of the suture among very young Neandertal children in comparison to the condition in extant ones. This suggests a longer independence of some parts of the premaxilla in Neandertals. To further examine this possibility, CT scans of two Neandertal children were analyzed: Roc de Marsal, estimated to be about 3 years, and Engis 2, estimated to be about 5-6 years. The results are quite different between the fossils. In the older, the premaxillary suture is represented only by a deep groove. In the younger it extends deep to the surface of the nasal process reaching the Parinaud's canal. Synostosis of the premaxillary suture was found to occur later in Neandertal children than in modern ones. Moreover, we observed the existence of two interincisive sinuses in the fossil children, whereas this is rare in modern children (present on only 2% of our sample of 0-6 year-old infants, n = 247).Persistence of an open premaxillary suture represents the potential for an extended period of growth of the Neandertal mid-face. Although no trace of the premaxillary suture remains in adult Neandertals, Neandertals present many features classically considered as consequences of this persistence. The two interincisive sinuses could be a consequence of the labio-lingual diameter of the incisors. The results presented here can be further investigated by additional studies on the cranial sutural system and by precise morphologic observations and CT scans of the mid-face of a larger sample of fossil children.     

Did a discrete event 200,000-100,000 years ago produce modern humans?

Scenarios for modern human origins are often predicated on the assumption that modern humans arose 200,000-100,000 years ago in Africa. This assumption implies that something ‘special’ happened at this point in time in Africa, such as the speciation that produced Homo sapiens, a severe bottleneck in human population size, or a combination of the two. The common thread is that after the divergence of the modern human and Neandertal evolutionary lineages ∼400,000 years ago, there was another discrete event near in time to the Middle-Late Pleistocene boundary that produced modern humans. Alternatively, modern human origins could have been a lengthy process that lasted from the divergence of the modern human and Neandertal evolutionary lineages to the expansion of modern humans out of Africa, and nothing out of the ordinary happened 200,000-100,000 years ago in Africa.Three pieces of biological (fossil morphology and DNA sequences) evidence are typically cited in support of discrete event models. First, living human mitochondrial DNA haplotypes coalesce ∼200,000 years ago. Second, fossil specimens that are usually classified as ‘anatomically modern’ seem to appear shortly afterward in the African fossil record. Third, it is argued that these anatomically modern fossils are morphologically quite different from the fossils that preceded them.Here I use theory from population and quantitative genetics to show that lengthy process models are also consistent with current biological evidence. That this class of models is a viable option has implications for how modern human origins is conceptualized.     

The Spy VI child: a newly discovered Neandertal infant

Spy cave (Jemeppe-sur-Sambre, Belgium) is reputed for the two adult Neandertal individuals discovered in situ in 1886. Recent reassessment of the Spy collections has allowed direct radiocarbon dating of these individuals. The sorting of all of the faunal collections has also led to the discovery of the remains of a Neandertal child, Spy VI. This individual is represented by two mandibular corpus fragments. The left fragment is the most complete and both sides preserve the mental foramen. Four deciduous teeth are associated with these mandibular remains: three incisors and one canine. The lower left canine (Spy 645a) conjoins with the corresponding alveolar socket in the left part of the mandible. Following extant standards, the developmental stage of the preserved teeth indicate an age at death of about one and a half years. In addition to performing a classical morphometric comparative study of the mandible and teeth, we have evaluated the dental tissue proportions using high-resolution microtomographic techniques. Our results show that Spy VI generally falls within the Neandertal range of variation. However, this specimen also exhibits particular traits, notably in the dental internal structural organization, which reveals that variation in the immature Neandertal variation is larger than what was variation currently represented by the available fossil record. These observations demonstrate the need for investigating the frequency and expression of immature Neandertal traits in fossil anterior teeth, as well as their temporal and geographic variation. Direct radiocarbon dating of the Spy VI specimen has been conducted in two different laboratories. The results of Spy VI confirm the age previously determined for the two adults, making the Spy Neandertal remains the youngest ever directly dated in northwest Europe.     

Relative dental development of Upper Pleistocene hominids compared to human population variation

The relative development of permanent teeth in samples of Neandertal/archaic Homo and Early Modern/Upper Paleolithic hominids is compared to the range of variability found in three recent human samples. Both fossil hominid samples are advanced in relative M2 and M3 development compared to white French-Canadians, but only the Neandertal/archaic Homo M3 sample is advanced when compared to black southern Africans. Both fossil hominid samples are delayed in relative I1 and P3 development compared to the recent human samples. Two hypotheses concerning the significance of the advanced M3 and M2 development found in both hominid groups and southern Africans compared to French-Canadians are discussed. The first postulates that the differences in relative molar development are due simply to variation in tooth/jaw size relationships. The second postulates that the relatively advanced M3 and M2 development found in the fossil hominids and southern Africans is a correlate of their potential for advanced skeletal maturation compared to French-Canadians and other European-derived populations. It appears that dental development patterns have continued to evolve from the Upper Pleistocene to present times, and that Neandertals and Early Moderns shared similar patterns of relative dental development. © 1996 Wiley-Liss, Inc.     

Some aspects of dimorphism and human speech

The production of human speech involves thre supralaryngeal airway filtering the acoustic energy generated by either laryngeal or noise sources. Both the supralaryngeal vocal tract and the larynx are subject to sexual dimorphism in anatomically modernHomo sapiens, yielding acoustic signals that can convey a speaker’s sex. Formant frequencies can be lower because the adult male supralaryngeal vocal tract is often longer. The fundamental frequency of phonation also can be lower because of the enlargement of the thyroid cartilage of the larynx and concomitant increases in the length and mass of the vocal cords. Secondary, learned supralaryngeal vocal tract maneuvers can also lower or raise formant frequencies. These acoustic effects yield male-female «microphonetic» dialects that are ultimately related to the average dimorphism found in the adult population. The dimorphism anatomy of the supralaryngeal vocal tract and larynx of fossil hominoids can be inferred from their skulls.     

Neither phylogenomic nor palaeontological data support a Palaeogene origin of placental mammals

O''Leary et al. (O''Leary et al. 2013 Science 339, 662–667. (doi:10.1126/science.1229237)) performed a fossil-only dating analysis of mammals, concluding that the ancestor of placentals post-dated the Cretaceous–Palaeogene boundary, contradicting previous palaeontological and molecular studies that placed the ancestor in the Cretaceous. They incorrectly used fossil ages as species divergence times for crown groups, while in fact the former should merely form minimum-age bounds for the latter. Statistical analyses of the fossil record have shown that crown groups are significantly older than the oldest ingroup fossil, so that fossils do not directly reflect the true ages of clades. Here, we analyse a 20 million nucleotide genome-scale alignment in conjunction with a probabilistic interpretation of the fossil ages from O''Leary et al. Our combined analysis of fossils and molecules demonstrates that Placentalia originated in the Cretaceous.     

A new model of forelimb ecomorphology for predicting the ancient habitats of fossil turtles

Various morphological proxies have been used to infer habitat preferences among fossil turtles and their early ancestors, but most are tightly linked to phylogeny, thereby minimizing their predictive power. One particularly widely used model incorporates linear measurements of the forelimb (humerus + ulna + manus), but in addition to the issue of phylogenetic correlation, it does not estimate the likelihood of habitat assignment. Here, we introduce a new model that uses intramanual measurements (digit III metacarpal + non‐ungual phalanges + ungual) to statistically estimate habitat likelihood and that has greater predictive strength than prior estimators. Application of the model supports the hypothesis that stem‐turtles were primarily terrestrial in nature and recovers the nanhsiungchelyid Basilemys (a fossil crown‐group turtle) as having lived primarily on land, despite some prior claims to the contrary.     

Is Central Asia the eastern outpost of the Neandertal range? A reassessment of the Teshik‐Tash child

Since its discovery in southeastern Uzbekistan in 1938, the Teshik-Tash child has been considered a Neandertal. Its affinity is important to studies of Late Pleistocene hominin growth and development as well as interpretations of the Central Asian Middle Paleolithic and the geographic distribution of Neandertals. A close examination of the original Russian monograph reveals the incompleteness of key morphologies associated with the cranial base and face and problems with the reconstruction of the Teshik-Tash cranium, making its Neandertal attribution less certain than previously assumed. This study reassesses the Neandertal status of Teshik-Tash 1 by comparing it to a sample of Neandertal, Middle and Upper Paleolithic modern humans, and recent human sub-adults. Separate examinations of the cranium and mandible are conducted using multinomial logistic regression and discriminant function analysis to assess group membership. Results of the cranial analysis group Teshik-Tash with Upper Paleolithic modern humans when variables are not size-standardized, while results of the mandibular analysis place the specimen with recent modern humans for both raw and size-standardized data. Although these results are influenced by limitations related to the incomplete nature of the comparative sample, they suggest that the morphology of Teshik-Tash 1 as expressed in craniometrics is equivocal. Although, further quantitative studies as well as additional sub-adult fossil finds from this region are needed to ascertain the morphological pattern of this specimen specifically, and Central Asian Middle Paleolithic hominins in general, these results challenge current characterizations of this territory as the eastern boundary of the Neandertal range during the Late Pleistocene.     

Antarctic Crabs: Invasion or Endurance?

Recent scientific interest following the “discovery” of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This “invasion hypothesis” suggests that decapod crabs were driven out of Antarctica 40–15 million years ago and are only now returning as “warm” enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60°S. All are restricted to waters warmer than 0°C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day “crab invasion”. We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the “invasion hypothesis”.     

The anatomy, physiology, acoustics and perception of speech: essential elements in analysis of the evolution of human speech

Inferences on the evolution of human speech based on anatomical data must take into account its physiology, acoustics and perception. Human speech is generated by the supralaryngeal vocal tract (SVT) acting as an acoustic filter on noise sources generated by turbulent airflow and quasi-periodic phonation generated by the activity of the larynx. The formant frequencies, which are major determinants of phonetic quality, are the frequencies at which relative energy maxima will pass through the SVT filter. Neither the articulatory gestures of the tongue nor their acoustic consequences can be fractionated into oral and pharyngeal cavity components. Moreover, the acoustic cues that specify individual consonants and vowels are “encoded”, i.e., melded together. Formant frequency encoding makes human speech a vehicle for rapid vocal communication. Non-human primates lack the anatomy that enables modern humans to produce sounds that enhance this process, as well as the neural mechanisms necessary for the voluntary control of speech articulation. The specific claims of Duchin (1990) are discussed.