Human brain evolution : how the increase of brain plasticity made us a cultural species

Why are humans so different from other primate species? What makes us so capable of creating language, art and music? The specializations in human brain anatomy that are responsible for our unique behavioral and cognitive traits evolved over a very short period of evolutionary time (between six and eight million years). Recent evidence suggests that, alongside a reorganization of the brain and an increase in its size, neural plasticity may also play a major role in explaining the evolutionary history of our species. Plasticity is the propensity of the brain to be molded by external influences, including the ecological, social and cultural context. The impact of these environmental influences in shaping human behavior has been long recognized, but it has been only recently that scientists have started discovering the more pronounced plasticity of human brains compared to our close relatives

Neanderthal teeth from Lezetxiki (Arrasate, Iberian Peninsula): New insights and reassessment

Objectives We reassess the taxonomic assignment and stratigraphic context of a permanent upper first molar and a permanent lower third premolar recovered from the archeological site of Lezetxiki in the North of the Iberian Peninsula. Materials and Methods We assessed the external and internal morphology of the teeth using qualitative descriptions, crown diameters, dental tissue proportions, and geometric morphometrics. The teeth from Lezetxiki were compared with Middle Pleistocene specimens, Neanderthals, Upper Paleolithic modern humans, and recent modern humans. Results Both teeth were consistent with a Neanderthal classification. The upper first molar shows taurodontism, and its cusp proportions and overall morphology match those of Neanderthals. Geometric morphometric analyses of occlusal anatomy classify this molar as a Neanderthal with a posterior probability of 76%. The lower third premolar, which was originally classified as a lower fourth premolar, also shows a Neanderthal morphology. This premolar is classified as a Neanderthal with a posterior probability of 60%. Discussion These teeth represent the only adult Neanderthal teeth from the Western Pyrenees region found to date. The teeth were found at a stratigraphic level (designated Level III) that marks the transition level from Mousterian to Aurignacian, and are among the most recent Neanderthal remains from the north of the Iberian Peninsula.This work was funded by the Dirección General de Investigación of M.E.C, project number CGL2012-38434-C03-03 and MICINN PID202-1-122355N-B-C32; 2017 SGR 1630 Grup de recerca en Antropologia Biològica (GREAB), 2017 SGR 1040 Social, cultural and biological Evolution during the Pleistocene (StEP), and 2021 SGR 01239 of the Generalitat de Catalunya; and 2019 PFR-URV-91 and 22017 Research Groups. This study also received support from the French government in the framework of the University of Bordeaux‘s IdEx “Investments for the Future” program/GPR Human Past, and the scientific environmental support of the teams EVODIBIO and EURAPAL from PACEA-UMR5199. DLO was supported by the Basque Governments postdoctoral Fellowship (POS_2019_1_0024) and MSC Actions Individual Fellowship (Project No. 895713)

Comparative analysis of the Gran Dolina-TD6 (Spain) and Tighennif (Algeria) hominin mandibles

We present a comparative study of the Tighennif (Algeria) and Gran Dolina-TD6 (Spain) hominin mandibles, which represent two geographically near and contemporaneous populations separated by the Mediterranean sea, in order to test the hypothesis that these populations belong to the same evolutionary lineage, as it has been suggested by some authors. The Tighennif mandibles show a clear primitive structural pattern, derived in some features with regard to the oldest Homo specimens from H. habilis, as well as from the Javanese H. erectus. In addition, the Tighennif specimens share all these derived features with H. ergaster and, some of them, with H. antecessor. However, the Gran Dolina-TD6 specimens are remarkably smaller than those of Tighennif, and lack the robustness which characterizes the African Pleistocene mandibles. The main difference between both groups in terms of mandibular dimensions can be related to the higher corpus height characteristic of Tighennif specimens. The dental evidence reveals that North African Middle Pleistocene populations are morphologically closer to African Early Pleistocene populations than to TD6 fossils. We conclude that the Spanish and Algerian hominins belong to different hominin lineages. The Tighennif hominins, together with other contemporaneous (Thomas Quarry and Oulad Hamida 1), and perhaps later North African specimens (Sidi Abderrahaman, Salé, and Rabat [Kebitat]) should be considered as a subspecies of the H. ergaster species, i.e. H. ergaster mauritanicus, and may be the result of an evolution in isolation in this African area. In agreement with the mandibular and dental evidences, the Gran Dolina-TD6 hominins could belong to an exclusive Eurasian lineage.Nous présentons une analyse comparée des mandibules des hominidés de Tighennif (Algérie) et de la Gran Dolina-TD6 (Espagne), qui représentent deux populations proches dans l’espace et le temps mais séparées par la mer Méditerranée, afin de vérifier l’hypothèse que les deux échantillons appartiennent au même lignage évolutif, comme certains auteurs l’ont suggéré. Les mandibules de Tighennif ont un pattern morphologique structurel primitif, avec certains caractères dérivés par rapport à ceux des spécimens de H. habilis et de H. erectus de Java. Les mandibules de Tighennif partagent tous ces caractères dérivés avec H. ergaster et quelques uns avec H. antecessor. Néanmoins, les spécimens de la Gran Dolina-TD6 sont remarquablement plus petits que ceux de Tighennif, et sont moins robustes que les mandibules du Pléistocène d’Afrique. La principale différence entre les deux échantillons, en ce qui concerne les dimensions mandibulaires, est la grande hauteur du corps de la mandibule des spécimens de Tighennif. Les caractères dentaires révèlent que les populations du Pléistocène moyen du Nord de l’Afrique sont, du point de vue morphologique, plus proches des hominidés du Pléistocène inférieur de l’Afrique que de ceux de la Gran Dolina-TD6. Nous concluons donc que les hominidés de Tighennif et de la Gran Dolina-TD6 appartiennent à deux lignées différentes. Les hominidés de Tighennif pourraient être réunis avec les spécimens contemporains de Thomas Quarry et de Oulad Hamida 1, et peut-être avec d’autres plus tardifs comme ceux de Sidi Abderrahaman, Salé, et Rabat [Kebitat] du Nord de l’Afrique dans une même sous-espèce de H. ergaster, i.e. H. ergaster mauritanicus, qui serait le résultat d’une évolution locale en isolement relatif dans cette région de l’Afrique. Les hominidés de la Gran Dolina-TD6 appartiennent à une lignée exclusive de l’Eurasie, conformément aux données dentaires et mandibulaires

No known hominin species matches the expected dental morphology of the last common ancestor of Neanderthals and modern humans

A central problem in paleoanthropology is the identity of the last common ancestor of Neanderthals and modern humans ([N-MH]LCA). Recently developed analytical techniques now allow this problem to be addressed using a probabilistic morphological framework. This study provides a quantitative reconstruction of the expected dental morphology of the [N-MH]LCA and an assessment of whether known fossil species are compatible with this ancestral position. We show that no known fossil species is a suitable candidate for being the [N-MH]LCA and that all late Early and Middle Pleistocene taxa from Europe have Neanderthal dental affinities, pointing to the existence of a European clade originated around 1 Ma. These results are incongruent with younger molecular divergence estimates and suggest at least one of the following must be true: (i) European fossils and the [N-MH]LCA selectively retained primitive dental traits; (ii) molecular estimates of the divergence between Neanderthals and modern humans are underestimated; or (iii) phenotypic divergence and speciation between both species were decoupled such that phenotypic differentiation, at least in dental morphology, predated speciation

Serum micrornas as tool to predict early response to benralizumab in severe eosinophilic asthma

Severe eosinophilic asthma poses a serious health and economic problem, so new therapy approaches have been developed to control it, including biological drugs such as benralizumab, which is a monoclonal antibody that binds to IL-5 receptor alpha subunit and depletes peripheral blood eosinophils rapidly. Biomarkers that predict the response to this drug are needed so that microRNAs (miRNAs) can be useful tools. This study was performed with fifteen severe eosinophilic asthmatic patients treated with benralizumab, and serum miRNAs were evaluated before and after treatment by semi-quantitative PCR (qPCR). Patients showed a clinical improvement after benralizumab administration. Additionally, deregulation of miR-1246, miR-5100 and miR-338-3p was observed in severe asthmatic patients after eight weeks of therapy, and a correlation was found between miR-1246 and eosinophil counts, including a number of exacerbations per year in these severe asthmatics. In silico pathway analysis revealed that these three miRNAs are regulators of the MAPK signaling pathway, regulating target genes implicated in asthma such as NFKB2, NFATC3, DUSP1, DUSP2, DUSP5 and DUSP16. In this study, we observed an altered expression of miR-1246, miR-5100 and miR-338-3p after eight weeks of benralizumab administration, which could be used as early response markers.This manuscript was funded by Fondo de Investigación Sanitaria–FIS and FEDER (Fondo Europeo de Desarrollo Regional) [PI15/00803, PI18/00044, and FI16/00036], CIBER de Enfermedades Respiratorias (CIBERES), Merck Health Foundation funds, and Ministerio de Ciencia, Innovación y Universidades (RTC-2017-6501-1

From fossils to mind

Fossil endocasts record features of brains from the past: size, shape, vasculature, and gyrification. These data, alongside experimental and comparative evidence, are needed to resolve questions about brain energetics, cognitive specializations, and developmental plasticity. Through the application of interdisciplinary techniques to the fossil record, paleoneurology has been leading major innovations. Neuroimaging is shedding light on fossil brain organization and behaviors. Inferences about the development and physiology of the brains of extinct species can be experimentally investigated through brain organoids and transgenic models based on ancient DNA. Phylogenetic comparative methods integrate data across species and associate genotypes to phenotypes, and brains to behaviors. Meanwhile, fossil and archeological discoveries continuously contribute new knowledge. Through cooperation, the scientific community can accelerate knowledge acquisition. Sharing digitized museum collections improves the availability of rare fossils and artifacts. Comparative neuroanatomical data are available through online databases, along with tools for their measurement and analysis. In the context of these advances, the paleoneurological record provides ample opportunity for future research. Biomedical and ecological sciences can benefit from paleoneurology's approach to understanding the mind as well as its novel research pipelines that establish connections between neuroanatomy, genes and behavior

What do brain endocasts tell us? A comparative analysis of the accuracy of sulcal identification by experts and perspectives in palaeoanthropology

Palaeoneurology is a complex field as the object of study, the brain, does not fossilize. Studies rely therefore on the (brain) endocranial cast (often named endocast), the only available and reliable proxy for brain shape, size and details of surface. However, researchers debate whether or not specific marks found on endocasts correspond reliably to particular sulci and/or gyri of the brain that were imprinted in the braincase. The aim of this study is to measure the accuracy of sulcal identification through an experiment that reproduces the conditions that palaeoneurologists face when working with hominin endocasts. We asked 14 experts to manually identify well-known foldings in a proxy endocast that was obtained from an MRI of an actual in vivo Homo sapiens head. We observe clear differences in the results when comparing the non-corrected labels (the original labels proposed by each expert) with the corrected labels. This result illustrates that trying to reconstruct a sulcus following the very general known shape/position in the literature or from a mean specimen may induce a bias when looking at an endocast and trying to follow the marks observed there. We also observe that the identification of sulci appears to be better in the lower part of the endocast compared to the upper part. The results concerning specific anatomical traits have implications for highly debated topics in palaeoanthropology. Endocranial description of fossil specimens should in the future consider the variation in position and shape of sulci in addition to using models of mean brain shape. Moreover, it is clear from this study that researchers can perceive sulcal imprints with reasonably high accuracy, but their correct identification and labelling remains a challenge, particularly when dealing with extinct species for which we lack direct knowledge of the brain

POR UNA CULTURA DE PAZ: UNA MIRADA DESDE LAS CIENCIAS DE LA CONDUCTA

En
 virtud
 de
 lo
 anterior,
 los
 estudiosos
 de
 las
 ciencias
 de
 la
 conducta
 
de
 la
 Universidad
Autónoma 
del
 Estado 
de 
México,

ante 
la
persistencia
 y 
proliferación
 de
 estos 
hechos
 en
 diversas
 partes
 del
Mundo
 y
 de
 nuestro 
país 
en 
particular, se
 convocó
 a
 los
 estudiosos
 interesados
 y
 a
 la
 sociedad
 en
 general
 a
 presentar
 trabajos
 para
 analizar,
 debatir
 y
 proponer
 estrategias
 de
 acción
 y
 dirección,
 que
 fortalezcan
 una
 convivencia y bienestar con sentido humanista para una cultura de paz. El
 presente
 texto
 es
 producto
 de 
esta convocatoria 
que
 recoge 
los
trabajos 
de 

los
 interesados 
en 
la
 temática,

 de
 diferentes 
países
(España,
Argentina,
Cuba,
Brasil,
Costa
 Rica
 y
 México)
 retomando
 con
 ello
 sus
 experiencias
 relativas
 al
 estudio,
 análisis,
 comprensión
 e
 instrumentación
 de
 la
 cultura
 de
 paz
 en
 los
 distintos
 ámbitos
 institucionales
 en
 los
 que
 participan:
 educativo,
 salud,
 penitenciario,
 social,
laboral,
familia,
alimentario,
psicológico,
por 
mencionar 
algunos.
 El
 presente
 libro,
 propicia
 un
 espacio
 de
 reflexión,
 diálogo
 y
 posicionamiento
 de
 las 
ciencias 
de 
la 
conducta
 para 
la 
apropiación,
análisis,
debate
 y 
propuestas 
que
 fortalezcan 
una
 cultura
 de 
paz
 a
través
 de 
la
 convivencia 
y
 el 
bienestar
 social 
con
 sentido 
humanista.
El
 sistema 
económico
 neoliberal
 y 
el 
proceso
 de 
globalización 
han
 contribuido
al
 logro
 de
 avances
 significativos
 en
 la
 ciencia
 y
 la
 tecnología,
 pero
 también
 han
 propiciado
 la
 polarización
 de
 las
 sociedades
 lo
 que
 ha
 impactado
 de
 manera
 negativa
 a
 la
 sociedad
 en
 su
 conjunto,
 pero
 en
 mayor
 medida
 a
 los grupos
 vulnerables. Dicha
 polarización
 ha
 traído
 consigo
 un
 desarrollo
 desigual
 del
 mundo
 que
 se
 expresa
 de
 diferentes
 maneras
 tanto
 en
 países
 desarrollados
 como
 en
 los
 llamados
 del
 tercer
 mundo,
 en
 donde
 no
 están
 satisfechas
 las
 necesidades
 humanas 
elementales
 de
 todos 
los
sectores 
de 
la 
población,
siempre 
falta 
algo. 
Si 
a
 esto 
le
 sumamos 
los
conflictos
 internacionales por
 diferentes
 motivos
 que
 enfrentan
 algunas
 naciones,
 una
 insuficiente
 cobertura
 educativa
 y
 de
 salud,

 desempleo
 y
 pobreza 
extrema,
 entre 
otras
 cosas; 
estamos
 frente
 a
retos 
de
 gran
 envergadura
 para
 los
 gobiernos,
 para
 los
 estudiosos
 y
 para
 la
 sociedad
 civil
 en
 general. Uno 
de 
los
 intentos
 para
 frenar 
y prevenir 
la
 agudización
 de 
estas 
problemáticas
 es
 la
 cultura 
de 
paz,
cuyo
 estudio
y propuestas 
han 
ido 
avanzando 
en 
diferentes
 sentidos 
y 
de 
manera 
favorable,
el 
tema 
está 
presente 
en 
diferentes 
Organismos
 Internacionales
 como
 la
 ONU,
 la
 UNESCO,
 la
 OCDE,
 El
 Banco
 Mundial,
 entre
 otros.
 Pero
 falta 
mucho 
por 
hacer.Universidad Autónoma del Estado de Méxic

Comprehensive analysis and insights gained from long-term experience of the Spanish DILI Registry

[Background & Aims] Prospective drug-induced liver injury (DILI) registries are important sources of information on idiosyncratic DILI. We aimed to present a comprehensive analysis of 843 patients with DILI enrolled into the Spanish DILI Registry over a 20-year time period.[Methods] Cases were identified, diagnosed and followed prospectively. Clinical features, drug information and outcome data were collected.[Results] A total of 843 patients, with a mean age of 54 years (48% females), were enrolled up to 2018. Hepatocellular injury was associated with younger age (adjusted odds ratio [aOR] per year 0.983; 95% CI 0.974–0.991) and lower platelet count (aOR per unit 0.996; 95% CI 0.994–0.998). Anti-infectives were the most common causative drug class (40%). Liver-related mortality was more frequent in patients with hepatocellular damage aged ≥65 years (p = 0.0083) and in patients with underlying liver disease (p = 0.0221). Independent predictors of liver-related death/transplantation included nR-based hepatocellular injury, female sex, higher onset aspartate aminotransferase (AST) and bilirubin values. nR-based hepatocellular injury was not associated with 6-month overall mortality, for which comorbidity burden played a more important role. The prognostic capacity of Hy’s law varied between causative agents. Empirical therapy (corticosteroids, ursodeoxycholic acid and MARS) was prescribed to 20% of patients. Drug-induced autoimmune hepatitis patients (26 cases) were mainly females (62%) with hepatocellular damage (92%), who more frequently received immunosuppressive therapy (58%).[Conclusions] AST elevation at onset is a strong predictor of poor outcome and should be routinely assessed in DILI evaluation. Mortality is higher in older patients with hepatocellular damage and patients with underlying hepatic conditions. The Spanish DILI Registry is a valuable tool in the identification of causative drugs, clinical signatures and prognostic risk factors in DILI and can aid physicians in DILI characterisation and management.[Lay summary] Clinical information on drug-induced liver injury (DILI) collected from enrolled patients in the Spanish DILI Registry can guide physicians in the decision-making process. We have found that older patients with hepatocellular type liver injury and patients with additional liver conditions are at a higher risk of mortality. The type of liver injury, patient sex and analytical values of aspartate aminotransferase and total bilirubin can also help predict clinical outcomes.The present study has been supported by grants of Instituto de Salud Carlos III cofounded by Fondo Europeo de Desarrollo Regional – FEDER (contract numbers: PI19/00883, PI16/01748, PI18/00901, PI18/01804, PI-0285-2016, PI-0274-2016, PI-0310-2018, PT17/0017/0020) and Agencia Española del Medicamento. CIBERehd and Plataforma ISCIII Ensayos Clinicos are funded by Instituto de Salud Carlos III. MRD holds a Joan Rodes (JR16/00015)/Acción B clinicos investigadores (B-0002-2019) and JSC a Rio Hortega (CM17/00243) research contract from ISCIII and Consejería de Salud de Andalucía.Peer reviewe