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Fulltext Genomes of Pleistocene Siberian Wolves Uncover Multiple Extinct Wolf Lineages

Ramos-Madrigal J, Sinding MS, Carøe C, Mak SST, Niemann J, Samaniego Castruita JA, et al.

Curr Biol, 2021 01 11;31(1):198-206.e8.
PMID: 33125870 DOI: 10.1016/j.cub.2020.10.002

Extant Canis lupus genetic diversity can be grouped into three phylogenetically distinct clades: Eurasian and American wolves and domestic dogs.1 Genetic studies have suggested these groups trace their origins to a wolf population that expanded during the last glacial maximum (LGM)1-3 and replaced local wolf populations.4 Moreover, ancient genomes from the Yana basin and the Taimyr peninsula provided evidence of at least one extinct wolf lineage that dwelled in Siberia during the Pleistocene.35 Previous studies have suggested that Pleistocene Siberian canids can be classified into two groups based on cranial morphology. Wolves in the first group are most similar to present-day populations, although those in the second group possess intermediate features between dogs and wolves.67 However, whether this morphological classification represents distinct genetic groups remains unknown. To investigate this question and the relationships between Pleistocene canids, present-day wolves, and dogs, we resequenced the genomes of four Pleistocene canids from Northeast Siberia dated between >50 and 14 ka old, including samples from the two morphological categories. We found these specimens cluster with the two previously sequenced Pleistocene wolves, which are genetically more similar to Eurasian wolves. Our results show that, though the four specimens represent extinct wolf lineages, they do not form a monophyletic group. Instead, each Pleistocene Siberian canid branched off the lineage that gave rise to present-day wolves and dogs. Finally, our results suggest the two previously described morphological groups could represent independent lineages similarly related to present-day wolves and dogs.

Matched MeSH terms: Skull/anatomy & histology
Study on the performance of different craniofacial superimposition approaches (I)

Ibáñez O, Vicente R, Navega DS, Wilkinson C, Jayaprakash PT, Huete MI, et al.

Forensic Sci Int, 2015 Dec;257:496-503.
PMID: 26060056 DOI: 10.1016/j.forsciint.2015.05.030

As part of the scientific tasks coordinated throughout The 'New Methodologies and Protocols of Forensic Identification by Craniofacial Superimposition (MEPROCS)' project, the current study aims to analyse the performance of a diverse set of CFS methodologies and the corresponding technical approaches when dealing with a common dataset of real-world cases. Thus, a multiple-lab study on craniofacial superimposition has been carried out for the first time. In particular, 26 participants from 17 different institutions in 13 countries were asked to deal with 14 identification scenarios, some of them involving the comparison of multiple candidates and unknown skulls. In total, 60 craniofacial superimposition problems divided in two set of females and males. Each participant follow her/his own methodology and employed her/his particular technological means. For each single case they were asked to report the final identification decision (either positive or negative) along with the rationale supporting the decision and at least one image illustrating the overlay/superimposition outcome. This study is expected to provide important insights to better understand the most convenient characteristics of every method included in this study.

Matched MeSH terms: Skull/anatomy & histology*
Study on the criteria for assessing skull-face correspondence in craniofacial superimposition

Ibáñez O, Valsecchi A, Cavalli F, Huete MI, Campomanes-Alvarez BR, Campomanes-Alvarez C, et al.

Leg Med (Tokyo), 2016 Nov;23:59-70.
PMID: 27890106 DOI: 10.1016/j.legalmed.2016.09.009

Craniofacial superimposition has the potential to be used as an identification method when other traditional biological techniques are not applicable due to insufficient quality or absence of ante-mortem and post-mortem data. Despite having been used in many countries as a method of inclusion and exclusion for over a century it lacks standards. Thus, the purpose of this research is to provide forensic practitioners with standard criteria for analysing skull-face relationships. Thirty-seven experts from 16 different institutions participated in this study, which consisted of evaluating 65 criteria for assessing skull-face anatomical consistency on a sample of 24 different skull-face superimpositions. An unbiased statistical analysis established the most objective and discriminative criteria. Results did not show strong associations, however, important insights to address lack of standards were provided. In addition, a novel methodology for understanding and standardizing identification methods based on the observation of morphological patterns has been proposed.

Matched MeSH terms: Skull/anatomy & histology*
A cephalometric study of the Chinese in profile

Cheng FG

Aust Orthod J, 1986 Mar;9(3):285-8.
PMID: 3463299
Matched MeSH terms: Skull/anatomy & histology*
Fulltext Morphometric approach to 3D soft-tissue craniofacial analysis and classification of ethnicity, sex, and age

Agbolade O, Nazri A, Yaakob R, Ghani AA, Cheah YK

PLoS One, 2020;15(4):e0228402.
PMID: 32271782 DOI: 10.1371/journal.pone.0228402

BACKGROUND: The application of three-dimensional scan models offers a useful resource for studying craniofacial variation. The complex mathematical analysis for facial point acquisition in three-dimensional models has made many craniofacial assessments laborious.
METHOD: This study investigates three-dimensional (3D) soft-tissue craniofacial variation, with relation to ethnicity, sex and age variables in British and Irish white Europeans. This utilizes a geometric morphometric approach on a subsampled dataset comprising 292 scans, taken from a Liverpool-York Head Model database. Shape variation and analysis of each variable are tested using 20 anchor anatomical landmarks and 480 sliding semi-landmarks.
RESULTS: Significant ethnicity, sex, and age differences are observed for measurement covering major aspects of the craniofacial shape. The ethnicity shows subtle significant differences compared to sex and age; even though it presents the lowest classification accuracy. The magnitude of dimorphism in sex is revealed in the facial, nasal and crania measurement. Significant shape differences are also seen at each age group, with some distinct dimorphic features present in the age groups.
CONCLUSIONS: The patterns of shape variation show that white British individuals have a more rounded head shape, whereas white Irish individuals have a narrower head shape. White British persons also demonstrate higher classification accuracy. Regarding sex patterns, males are relatively larger than females, especially in the mouth and nasal regions. Females presented with higher classification accuracy than males. The differences in the chin, mouth, nose, crania, and forehead emerge from different growth rates between the groups. Classification accuracy is best for children and senior adult age groups.

Matched MeSH terms: Skull/anatomy & histology*
Craniodental affinities of Southeast Asia's "negritos" and the concordance with their genetic affinities

Bulbeck D

Hum Biol, 2013 Feb-Jun;85(1-3):95-133.
PMID: 24297222

Genetic research into Southeast Asia's "negritos" has revealed their deep-rooted ancestry, with time depth comparable to that of Southwest Pacific populations. This finding is often interpreted as evidence that negritos, in contrast to other Southeast Asians, can trace much of their ancestry directly back to the early dispersal of Homo sapiens in the order of 70 kya from Africa to Pleistocene New Guinea and Australia. One view on negritos is to lump them and Southwest Pacific peoples into an "Australoid" race whose geographic distribution had included Southeast Asia prior to the Neolithic incursion of "Mongoloid" farmers. Studies into Semang osteology have revealed some hints of Southwest Pacific affinities in cranial shape, dental morphology, and dental metrical "shape." On the other hand, the Andamanese have been shown to resemble Africans in their craniometrics and South Asians in their dental morphology, while Philippine negritos resemble Mongoloid Southeast Asians in these respects and also in their dental metrics. This study expands the scope of negrito cranial comparisons by including Melayu Malays and additional coverage of South Asians. It highlights the distinction between the Mongoloid-like Philippine negritos and the Andamanese and Semang (and Senoi of Malaya) with their non-Mongoloid associations. It proposes that the early/mid-Holocene dispersal of the B4a1a mitochondrial DNA clade across Borneo, the Philippines, and Taiwan may be important for understanding the distinction between Philippine and other negritos.

Matched MeSH terms: Skull/anatomy & histology*
Fulltext Craniofacial anthropometric norms of Malays

Ngeow WC, Aljunid ST

Singapore Med J, 2009 May;50(5):525-8.
PMID: 19495526

INTRODUCTION: This study was undertaken to establish the craniofacial anthropometric norms of young adult Malaysian Malays.
METHODS: The study group consisted of convenient samples of 100 healthy volunteers (aged 18-25 years), with an equal number of female and male subjects who had no history of mixed racial parentage. 22 linear measurements were taken twice from 22 landmarks over six craniofacial regions.
RESULTS: The Malays shared many similar sizes of measurements with the Singaporean Chinese. Their left eye fissure length and mouth width (ch-ch) were almost identical for both genders. However, Malay females had an upper lip height (sn-sto) (left) and ear width (pra-pa) similar to Singaporean Chinese females. Six other measurements, viz. the head width (eu-eu), head circumference (on-op), face height (n-gn), lower face height (sn-gn), (left) eye fissure height (ps-pi), cutaneous upper lip height (sn-ls) and cutaneous upper lip height (ls-sto), were 0.4-4.3 mm less in the Malays. Measurements for another four parameters, viz. the length of the head (g-op), biocular width (ex-ex), lower vermillion height (sto-li) and (left) ear length (sa-sba), were 0.5-3.6 mm higher in the Malays. Only three measurements were obviously different; the height of the head (v-n) and intercanthal width (en-en), were lower, and the protrusion of the nasal tip (sn-prn) was higher in the Malays.
CONCLUSION: These findings suggest that three features, i.e. the height of the head (v-n), intercanthal width (en-en) and protrusion of the nasal tip (sn-prn) may be useful in differentiating a Malay face from a Singaporean Chinese one.

Matched MeSH terms: Skull/anatomy & histology*
Endoscopic fenestration at the splenial-habenular junctional area for symptomatic cavum and tumor at the foramen of Monro: case reports and anatomical review

Idris Z, Johnson JR, Abdullah JM

J. Neurosurg., 2015 Mar;122(3):504-10.
PMID: 25343181 DOI: 10.3171/2014.9.JNS132683

The splenial-habenular junctional area is an alternative site for neuroendoscopic fenestration to divert CSF flow into the quadrigeminal cistern in cases in which endoscopic third ventriculostomy is not amenable. In some patients with obstructive hydrocephalus, the splenium of the corpus callosum can be elevated from the habenular complex. This exposes the membranous connection between the splenium and habenula, which can be fenestrated to divert the CSF flow into the quadrigeminal cistern. This technique can be performed in patients in whom the foramen of Monro or the third ventricle is blocked by a lesion. Here, the authors present 3 complex cases that were managed by neuronavigation-guided transventricular transcavum endoscopic fenestration of the splenial-habenular junctional area. These cases may increase the knowledge and understanding of the anatomy of this region.

Matched MeSH terms: Skull/anatomy & histology