Dental Remains Research Articles

Cainotheriidae (Mammalia, Artiodactyla) from Dams (Quercy, SW France): phylogenetic relationships and evolution around the Eocene–Oligocene transition (MP19–MP21)

Cainotheriids are a family of small artiodactyls, known in the fossil record from the late Eocene to the middle Miocene in Western Europe. Contrary to several European endemic ungulate groups that became extinct at the end of the Eocene or close to the Eocene–Oligocene transition (Grande Coupure), cainotheriids crossed this boundary and diversified during the Oligocene. The evolutionary history of cainotheriids around the Grande Coupure remains poorly documented and only a few works deal with the modalities of their evolution, notably because of the scarcity of available Eocene remains. A new fossiliferous karstic network named Dams was discovered during field prospecting in the Quercy area (Tarn-et-Garonne, France). It notably displays two infillings that yielded a great abundance of cainotheriid remains, namely DAM1 (MP19, late Eocene) and DAM3 (MP22, early Oligocene), bracketing the Eocene–Oligocene transition. A detailed study of cainotheriid mandibular and dental remains from these infillings reveals that only Paroxacron valdense occurs at DAM1, while five species are found in DAM3. The karstic network at Dams seemingly records a local taxonomic diversification of cainotheriids after the Grande Coupure, with Cainotheriinae being particularly successful. Our phylogenetic analysis, including cainotheriids from Dams, constitutes the first formal phylogeny of Cainotheriidae. Our results, based on mandibular and dental characters, allow us to (i) clarify relationships within Cainotheriidae, (ii) erect a new family Robiacinidae, as being the sister taxon to Cainotheriidae among Cainotherioidea, and, more broadly, (iii) discuss the controversial position of Cainotheriidae within Artiodactyla, as being more closely related to Ruminantia than to Tylopoda.http://zoobank.org/urn:lsid:zoobank.org:pub:1F237FB2-480D-4A03-9089-379204EDEFB2

Optimizing DNA recovery and forensic typing of degraded blood and dental remains using a specialized extraction method, comprehensive qPCR sample characterization, and massively parallel sequencing

Human dental remains encountered in criminal casework evidence, missing person cases, or mass disaster tragedies provide a valuable sample source for DNA typing when suitable soft tissue is unavailable. Using traditional methods, teeth samples can be challenging to process, resulting in low-quantity and/or quality nuclear DNA and insufficient profiles for comparisons. This study examines the performance of a three-part nuclear DNA analysis workflow for teeth samples based on (1) improved dental tissue recovery using the Dental Forensic Kit (DFKMR) (Universidad de los Andes) and DNA extraction with QuickExtract™ FFPE DNA Extraction Kit (Lucigen®), (2) quantification with InnoQuant® HY (InnoGenomics Technologies) for sensitive assessment of total human and male DNA quantity/quality, and (3) massively parallel sequencing for simultaneous genotyping of 231 short tandem repeat (STR) and single-nucleotide polymorphism (SNP) markers with the ForenSeq® DNA Signature Prep Kit (Verogen, Inc.). Initial evaluation of artificially degraded blood samples (n = 10) achieved highly sensitive and informative quantification results with InnoQuant® HY, enabling successful first pass genotyping with the MiSeq FGx® System. Twenty-three STR alleles (out of 85) and 70 identity informative SNP loci (out of 94) were recovered from two pg total long target DNA input (0.86 ng total short target input) and an InnoQuant degradation index (DI) of 460 (severely degraded). The three-part workflow was subsequently applied to teeth samples (dental pulp, root cement tissues; n = 13) with postmortem intervals (PMI) of the teeth ranging from 8 days to approximately 6 months. Informative SNP and STR DNA profiles were obtained, to include 78 STR alleles and 85 identity informative SNP loci typed (of 94 total SNP targets) in a 1 month, four-day PMI root cement sample with one pg total long target DNA input and a DI of 76. These data indicate successful performance of the proposed workflow from degraded DNA from teeth samples.

Optimization of DNA extraction from dental remains.

Efficient DNA extraction procedures is a critical step involved in the process of successful DNA analysis of such samples. Various protocols have been devised for the genomic DNA extraction from human tissues and forensic stains, such as dental tissue that is the skeletal part that better preserves DNA over time. However DNA recovery is low and protocols require labor‐intensive and time‐consuming step prior to isolating genetic material. Herein, we describe an extremely fast procedure of DNA extraction from teeth compared to classical method. Sixteen teeth of 100‐year‐old human remains were divided into two groups of 8 teeth and we compared DNA yield, in term of quantity and quality, starting from two different sample preparation steps. Specifically, teeth of group 1 were treated with a classic technique based on several steps of pulverization and decalcification, while teeth of group 2 were processed following a new procedure to withdraw dental pulp. In the next phase, the samples of both group underwent the same procedure of extraction, quantification and DNA profile analysis. Our findings provide an alternative protocol to obtain a higher amount of good quality DNA in a fast time procedure, helpful for forensic and anthropological studies.

Application of Trace Elemental Profile of Known Teeth for Sex and Age Estimation of Ajnala Skeletal Remains: a Forensic Anthropological Cross-Validation Study.

Teeth store crucial information needed for medical, environmental, genomics, public health, and forensic anthropological research work. The prolonged forensic utility of teeth is ensured by their extended postmortem longevity as they can resist almost all sorts of chemical, biological, and physical degradations or destructions. The main aim of the present investigation was to utilize the discriminant functions and regression equations generated from the elemental profile of known teeth for estimating sex and age of unknown human skeletal remains excavated from an abandoned well at Ajnala (Amritsar, India). The written records mentioned that 282 Indian mutineer soldiers were killed in July 1857, their cadavers were dumped in the disused well, and then a religious structure was built over the periphery of the said well. These human remains, along with some contextual items, were excavated non-scientifically in April 2014. Preliminary results obtained from application of different forensic anthropological techniques like stable isotope, pulp-tooth area ratio, and mtDNA analyses have indicated that these remains belonged to adult males. In present study, the elemental concentrations of 100 mandibular molars of known age and sex were estimated from wavelength-dispersive X-ray fluorescence spectrophotometer (WD-XRF) analyzer. The statistical equations so generated from elemental concentrations of known teeth were applied to estimate the probable age and the sex of unknown mandibular teeth (N = 100) collected from Ajnala skeletal assemblage. The elements Pb and As were detected in ancient teeth only whereas the detection of elements like Ba, Se, and Te was limited to modern teeth samples only. When the statistical equations so generated were applied to elemental concentrations of Ajnala teeth, it was found that 96% teeth belonged to adult males and the remaining ones were classified to be that of females. Though sexual differences were observed in concentrations of majority of elements, statistically significant differences were found in elemental concentrations of very few teeth. Age estimates of unknown teeth were found in the age ranges of 19 to 48years. Thus, the trace elemental analysis results supported the written records that the victims were adult males. The cross-validated application of elemental profiles of known teeth for establishing the identity of unknown teeth is the first forensic anthropological study reported from India. Though the obtained accuracy levels were not found within acceptable forensic threshold limits, the present study results may guide future researches involving human hard tissues. It may be concluded that trace elemental concentrations of teeth may be influenced by the factors like age and sex of an individual and thus cannot be used for accurate and reliable forensic sex or age estimations. Dental trace elemental composition can be used as a forensic tool only if used in conjunction with other morphological or molecular analysis of the unknown dental remains.

Anisodon (Perissodactyla, Chalicotheriinae) from the middle Miocene locality Gračanica (Bugojno Basin, Gornji Vakuf, Bosnia and Herzegovina)

The fossil mammal fauna of the Gracanica coal mine in central Bosnia and Herzegovina includes dental remains of Anisodon (Perissodactyla, Chalicotheriidae, Chalicotheriinae). These teeth most closely resemble those of Anisodon grande from Sansan (France, MN6) and Neudorf an der March (Slovakia, MN6), and are tentatively referred to that species. Anisodon is first known in Europe from the Loire Basin (France), which has been dated as MN5. Given that the Gracanica fauna is considered to be MN5 or earliest MN6 (Langhian), the Gracanica chalicothere represents one of the earlier known finds of both the Chalicotheriinae and Anisodon in Europe. The first known members of the Chalicotheriinae are from the earliest Miocene of Asia. By the middle Miocene, Anisodon had appeared and is known from Asia and Europe, to which it had recently immigrated.

A new lophocyonid, Izmirictis cani gen. et sp. nov. (Carnivora: Mammalia), from the lower Miocene of Turkey

Lophocyonids are one of the more enigmatic groups of Carnivora in the European Miocene fossil record. Lophocyonids are clearly distinguished from other Feliformia by their peculiar lophodont dental morphology. For this reason, the systematic relationships of the family have been controversial. Here we describe and interpret dental remains from the early Miocene of Sabuncubeli, Turkey, which we attribute to a new genus and species: Izmirictis cani. The phylogenetic analysis allows us to include Izmirictis within a monophyletic group, Lophocyonidae new rank, characterized by the molarization of the anterior premolars (P3 and p4), the lophodont adaptation of the molar dentition and the complex morphology of the incisors. The phylogenetic analysis shows a close relationship between Izmirictis and primitive hyaenids (represented herein by Protictitherium). The divergence between Lophocyonidae and Hyaenidae is estimated by biochronological data to have occurred during the early Miocene (MN2). Dental microwear analysis, although limited by poor dental enamel preservation, indicates that the pronounced lophodonty in Izmirictis cani could be connected to a herbivorous feeding habit.http://zoobank.org/urn:lsid:zoobank.org:pub:8D75382D-6C22-41C1-A47F-BA3EAF766881

Shifting faunal baselines through the Quaternary revealed by cave fossils of eastern Australia.

Fossils from caves in the Manning Karst Region, New South Wales, Australia have long been known, but until now have never been assessed for their palaeontological significance. Here, we report on late Quaternary faunal records from eight caves in the region. Extinct Pleistocene megafaunal taxa are recognised in two systems and include giant echidnas (Tachyglossidae gen. et sp. indet.), devils (Sarcophilus laniarius), koalas (Phascolarctos stirtoni), marsupial ‘lions’ (Thylacoleo carnifex), and kangaroos (Macropus giganteus titan). Some caves contain skeletal remains of introduced exotics such as sheep and dogs, but also provide a rich record of small-bodied native species including Eastern Bettongs (Bettongia gaimardi), Eastern Chestnut Mice (Pseudomys gracilicaudatus), and White-footed Rabbit Rats (Conilurus albipes). These endemics are either locally extirpated or have suffered total extinction in the historic period. Their skeletal and dental remains were recorded as unmineralised surface specimens in the caves, indicating that they are recent in age. Extant populations have never been recorded locally, thus, their probable loss from the region in historic times had gone unnoticed in the absence of palaeo-evidence. Our findings suggest that the supposed habitat tolerances of such species have been substantially underestimated. It is highly likely that modern populations have suffered niche contraction since the time of European colonisation of the continent. The local extirpations of several species of digging mammal has likely led to decreased functionality of the current ecosystem.

Rhinocerotidae from the early middle Miocene locality Gračanica (Bugojno Basin, Bosnia-Herzegovina)

The early middle Miocene (European Land Mammal Zone MN5) locality Gracanica (Bugojno Basin, Bosnia-Herzegovina) has yielded numerous well-preserved dental remains of four Rhinocerotidae species: Brachypotherium brachypus, Lartetotherium sansaniense, Plesiaceratherium balkanicum sp. nov. and Hispanotherium cf. matritense. This rhinocerotid assemblage is typical of the Orleanian European Land Mammal Age and indicates a mesic woodland with diverse habitats from swampy forest to drier and more open environment.

A new genus of Proterotheriinae (Mammalia, Litopterna) from the Pleistocene of Uruguay

ABSTRACTWe describe a new genus and species of Proterotheriinae from the Pleistocene of Uruguay. Several taxonomic, biostratigraphic, paleoecological, and paleoenvironmental analyses and interpretations have been performed in a detailed study of the Litopterna (Mammalia, ‘Meridiungulata’) of Uruguay. The Proterotheriidae is the most diverse family of the Litopterna. In Uruguay, the record of the Proterotheriidae, although in many cases fragmentary, includes interesting specimens in particular contexts and different ages in the late Oligocene–late Pleistocene. The aim of this work is to reassess the specimens primarily assigned four decades ago to ‘Licaphrium’ aff. floweri, redescribing them, evaluating their taxonomic status in the context of the Proterotheriidae, and establishing the characters that allow the determination of this taxon as a new genus and species of Proterotheriinae: Uruguayodon alius. We redescribe two specimens of this new taxon, which include dental and postcranial remains. The diagnostic element is the last lower molar, which shows, among other characters, paraconid and paralophid in a very lingual position, smoothed metaflexid, and absence of entoflexid. The individuals were excavated from a sandy level of the San José Member of the Raigón Formation, a unit that has an endemic fauna, a pattern discussed here in a paleogeographic framework. The provenance of the analyzed specimens from Pleistocene layers is indicated by mammalian content and absolute ages, which support the presence of another genus of Proterotheriidae surviving into the Quaternary, in addition to Neolicaphrium recens.

The Humerus of Proterotheriidae (Mammalia, Litopterna) and Its Systematic Usefulness: The Case of “Proterotherium berroi” Kraglievich, 1930

Proterotheriidae constitute a group of small-medium native South American ungulates with high diversity during the early Miocene and the late Miocene (Santacrucian and Huayquerian SALMAs). Recent studies demonstrated the wide dental variability, useful in the discrimination of the species. The aim of this work is to analyze the humerus as a postcranial element that is usually not found in association with cranial remains, and to evaluate (qualitatively and quantitatively) its systematic usefulness. We used the only known specimen of “Proterotherium berroi”, re-describing and re-illustrating it. The Principal Components Analysis resulted in 2 components explaining 86% of the variance. The PCA showed a differentiation between the largest species—Diadiaphorus majusculus and Anisolophus floweri—and the remaining ones (an intermediate group consisting of “Proterotherium”, Tetramerorhinus, Eoauchenia, Proterotheriidae indet., and the smallest, Thoatherium minusculum). We establish that, although there are slight morphological differences in the distal epiphysis of the humeri of Proterotheriidae, they mostly correspond to gradual changes in characters with continuous variations not linked to any particular taxonomic entity. These are not enough to assure a generic or specific determination, except for Eoauchenia. The differences in humeri size are considerable and they could be used as a criterion for discriminating Diadiaphorus and Anisolophus, to which the largest specimens would belong. We consider “P. berroi” a probable synonym of Neolicaphrium recens, but we ratify that a reliable systematic determination is only possible if it is based on cranial or dental remains.

Microlithic, faunal, floral and isotopic data from an archaeological site 14C dated to LGM in the eastern state of Odisha, India

The eastern state of Odisha, India is well known for its rich microlithic assemblages; over 400 sites have been reported, including some with tools for heavy-duty tasks. However, due to the lack of associated vertebrate fossils from stratified horizons and absolute dates, their antiquity and associated environments are yet to be established. We report here, for the first time, in situ fossils of a ruminant 14C dated to 17,875 cal BP associated with microliths from a stratified Quaternary sequence exposed at Pratappur, District Mayurbhanj, Odisha. The dental remains of ruminants are taxonomically identified to be those of the cervid Rusa unicolor (sambar) and an unidentified bovid. Stable carbon and oxygen isotope values (δ13C = 1.9‰; δ18O = −1.83‰, VPDB) on the Rusa unicolor tooth reveal that it was a C4 grazer and lived in an arid environment during the end of the Last Glacial Maximum. However, the bovid-yielding carbonaceous sediments that lie immediately above the R. unicolor horizon have yielded a large number of pollen and spores, belonging to moist deciduous forest suggesting moderate rainfall. Pollens belong to brackish mangrove Nypa and Barringtonia indicating tidal influence and the existence of a coastal environment nearby.

Disentangling isolated dental remains of Asian Pleistocene hominins and pongines.

Scholars have debated the taxonomic identity of isolated primate teeth from the Asian Pleistocene for over a century, which is complicated by morphological and metric convergence between orangutan (Pongo) and hominin (Homo) molariform teeth. Like Homo erectus, Pongo once showed considerable dental variation and a wide distribution throughout mainland and insular Asia. In order to clarify the utility of isolated dental remains to document the presence of hominins during Asian prehistory, we examined enamel thickness, enamel-dentine junction shape, and crown development in 33 molars from G. H. R. von Koenigswald's Chinese Apothecary collection (11 Sinanthropus officinalis [= Homo erectus], 21 “Hemanthropus peii,” and 1 “Hemanthropus peii” or Pongo) and 7 molars from Sangiran dome (either Homo erectus or Pongo). All fossil teeth were imaged with non-destructive conventional and/or synchrotron micro-computed tomography. These were compared to H. erectus teeth from Zhoukoudian, Sangiran and Trinil, and a large comparative sample of fossil Pongo, recent Pongo, and recent human teeth. We find that Homo and Pongo molars overlap substantially in relative enamel thickness; molar enamel-dentine junction shape is more distinctive, with Pongo showing relatively shorter dentine horns and wider crowns than Homo. Long-period line periodicity values are significantly greater in Pongo than in H. erectus, leading to longer crown formation times in the former. Most of the sample originally assigned to S. officinalis and H. erectus shows greater affinity to Pongo than to the hominin comparative sample. Moreover, enamel thickness, enamel-dentine junction shape, and a long-period line periodicity value in the “Hemanthropus peii” sample are indistinguishable from fossil Pongo. These results underscore the need for additional recovery and study of associated dentitions prior to erecting new taxa from isolated teeth.

New pycnodontiform fishes (Actinopterygii, Neopterygii) from the Early Cretaceous of the Argentinian Patagonia

Here we describe new pycnodontiform fish material recovered from the marine Agrio Formation (lower Valanginian–lower Hauterivian) of the Neuquén Province in the south-western of Patagonia, Argentina. The new material include an incomplete skull and an incomplete prearticular dentition. The incomplete skull consists of some dermal and endochondral elements as well as dental remains and represents a new large-sized gyrodontid that is referred to a new species, Gyrodus huiliches. Gyrodus huiliches sp. nov. is characterized by a unique combination of tooth crown ornamentations and tooth shape separating it easily from all known Gyrodus species. The incomplete prearticular dentition shows a tooth arrangement and sculpture that resembles that of “Macromesodon” agrioensis –the previously only known pycnodontiform in the area. This allows revising this species, which was based on an isolated vomerine dentition and which we refer to a new genus, Tranawuen. The new Patagonian fishes reported here expand the knowledge of South American pycnodontiforms. We hypothesize that meanwhile the new Patagonian genus – Tranawuen– diverged from Gyrodus after it migrated into the eastern Pacific through the Hispanic Corridor during the Late Jurassic, the new species –Gyrodus huiliches– most likely diverged from a Central or South American species of Gyrodus. Both represent the youngest gyrodontid records and simultaneously the southernmost Early Cretaceous occurrences of pycnodontiform fishes.

Dietary niches of terrestrial cercopithecines from the Plio-Pleistocene Shungura Formation, Ethiopia: evidence from Dental Microwear Texture Analysis

This study aims to explore the feeding ecology of two terrestrial papionins, Papio and Theropithecus from the Shungura Formation in Ethiopia, the most complete stratigraphic and paleontological record of the African Plio-Pleistocene. Two aspects were evaluated using Dental Microwear Texture Analysis: differences in diet between the extinct genera and their extant relatives, and any potential dietary fluctuations over time. Amongst more than 2,500 cercopithecid dental remains, 154 Theropithecus molars and 60 Papio molars were considered. Thirty-nine extant wild baboons and 20 wild geladas were also considered. The results show that diets of extinct monkeys from Member G already differed between genera as it is the case for their extant representatives. The shearing facets on the Theropithecus molars display significant variations in microwear textures, suggesting several dietary shifts over time. Two events point to higher intakes of herbaceous monocots (tougher than dicots foliages), at about 2.91 Ma (between members B and C) and at 2.32 Ma (between members E and F). These two events are separated by an inverse trend at about 2.53 Ma (between members C and D). Some of these variations, such as between members E and F are supported by the enamel carbon isotopic composition of herbivorous mammals and with paleovegetation evidence.

Use of XRD and SEM/EDX to predict age and sex from fire-affected dental remains.

In fire scenarios, the application and accuracy of traditional odontological methods are often limited. Crystalline studies and elemental profiling have been evaluated for their applicability in determining biological profiles (age and sex) from human dentition, particularly fire- and heat-affected dental remains. Thirty-seven teeth were paired according to tooth type and donor age/sex for the analysis of crown and root surfaces pre- and post-incineration using X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDX). In unburned crowns, carbon (C) content showed a positive correlation with age, whereas phosphorus (P) and calcium (Ca) contents showed a negative correlation with age. In unburned roots, C, P and Ca contents also showed significant changes that were opposite of those observed in the crowns. In relation to sex, females exhibited a higher C ratio than males, whereas males showed significantly higher levels of oxygen (O), P and Ca in unburned roots. Incineration resulted in an increase in the crystallite size that correlated with increasing temperature. No differences in hydroxyapatite (HA) crystallite size were found between age groups; however, unburned teeth from females exhibited a larger crystallite size than did those from males. The challenges of using XRD with a 3D sample were overcome to allow analysis of whole teeth in a nondestructive manner. Further studies may be useful in helping predict the temperature of a fire.

Labial Tooth Wear and Culture

Surface alterations observed on the anterior teeth of prehistoric humans suggest that incisors are involved in many uses related to ingestion, manipulations, and dental care activities. These culture-related uses can be distinguished in dental remains from throughout major periods of human evolution.

Pakkokuhyus and Progenitohyus (Artiodactyla, Mammalia) from the Eocene of Southeast Asia are not Helohyidae: paleobiogeographical implications

Pakkokuhyus and Progenitohyus are two genera of primitive artiodactyls from the Eocene of Southeast Asia that have been referred to the family Helohyidae. However, recent advances in the phylogeny and systematics of basal artiodactyls suggest that the status of several Asian forms should be reassessed. In that frame, reexamination of the few dental remains known for Pakkokuhyus and Progenitohyus indicates that they very probably do not belong to the Helohyidae but to the Dichobunidae. The dental structure of the alleged helohyid Gobiohyus from Asia also suggests that the attribution of this genus to the Helohyidae is questionable. In that context, the representatives of the family Helohyidae probably originated in North America during the Middle Eocene and were never involved in dispersals between Eurasia and North America, contrary to the diacodexeids and homacodontids. This further suggests that the systematics of basal artiodactyls from Southeast Asia should be carefully reassessed.

An Artificial Human Tooth from the Neolithic Cemetery at Gebel Ramlah, Egypt

Excavations at the Gebel Ramlah cemetery, in Upper Egypt’s Western Desert, have provided numerous data concerning mortuary practices of the local Final Neolithic period populace. Previous articles have chronicled treatment of disturbed inhumations, in which great care had been taken to recover and rebury all grave goods and skeletal elements including, most notably, dental remains. In several cases, the Neolithic gravediggers apparently went so far as to reinsert, or to in other ways reincorporate, teeth that had fallen from their alveoli during handling. This report describes and interprets a new find, i.e., an anatomically accurate, life-size shell carving of a human incisor, that provides additional insight into the apparent importance of teeth to these desert people.

Primary Tooth Mineralization and Exfoliation Ages Calculated from the Moorrees-Fanning-Hunt Study

Staging of the formation of teeth and shedding of the primary teeth are particularly useful for age estimation of archaeological and forensic specimens, as well as for gauging whether a child’s tempo of maturation is progressing within normal limits. Staging can be done using radiographs or with direct inspection of dental remains. Standards for the primary dentition are scarce, but obviously needed for young children. This note provides tables, by sex, of the normative ages of the mineralization of three mandibular tooth types (c, m1, m2) as well as of root resorption and times of shedding of these tooth types. The data are transformed from charts developed by Moorrees, Fanning and Hunt (1963 Am J Phys Anthropol 21:99-108). Conversion to numeric form is intended to aid in using these data for statistical comparisons.

Franklin expedition lead exposure: New insights from high resolution confocal x-ray fluorescence imaging of skeletal microstructure.

In the summer of 1845, under the command of Sir John Franklin, 128 officers and men aboard Royal Navy ships HMS Erebus and HMS Terror sailed into Lancaster Sound and entered the waters of Arctic North America. The goal of this expedition was to complete the discovery of a northwest passage by navigating the uncharted area between Barrow Strait and Simpson Strait. Franklin and his crew spent the first winter at Beechey Island, where three crewmen died and were buried. In September 1846, the ships became stranded in ice off the northwest coast of King William Island, where they remained until April 1848. At that time, the crew, reduced to 105, deserted the ships and retreated south along the island’s western and southern shores in a desperate attempt to reach the mainland and via the Back River, to obtain aid at a Hudson’s Bay Company Post. Sadly, not one individual survived. Previous analyses of bone, hair, and soft tissue samples from expedition remains found that crewmembers’ tissues contained elevated lead (Pb) levels, suggesting that Pb poisoning may have contributed to their demise; however, questions remain regarding the timing and degree of exposure and, ultimately, the extent to which the crewmembers may have been impacted. To address this historical question, we investigated three hypotheses. First, if elevated Pb exposure was experienced by the crew during the expedition, we hypothesized that those sailors who survived longer (King William Island vs. Beechey Island) would exhibit more extensive uptake of Pb in their bones and vice versa. Second, we hypothesized that Pb would be elevated in bone microstructural features forming at or near the time of death compared with older tissue. Finally, if Pb exposure played a significant role in the failure of the expedition we hypothesized that bone samples would exhibit evidence of higher and more sustained uptake of Pb than that of a contemporary comparator naval population from the 19th century. To test these hypotheses, we analyzed bone and dental remains of crew members and compared them against samples derived from the Royal Navy cemetery in Antigua. Synchrotron-based high resolution confocal X-ray fluorescence imaging was employed to visualize Pb distribution within bone and tooth microstructures at the micro scale. The data did not support our first hypothesis as Pb distribution within the samples from the two different sites was similar. Evidence of Pb within skeletal microstructural features formed near the time of death lent support to our second hypothesis but consistent evidence of a marked elevation in Pb levels was lacking. Finally, the comparative analysis with the Antigua samples did not support the hypothesis that the Franklin sailors were exposed to an unusually high level of Pb for the time period. Taken all together our skeletal microstructural results do not support the conclusion that Pb played a pivotal role in the loss of Franklin and his crew.