Luminescence age calculation through Bayesian convolution of equivalent dose and dose-rate distributions:The De_Dr model

In nature, each mineral grain (quartz or feldspar) receives a dose rate (Dr) specific to its environment. The dose-rate distribution, therefore, reflects the micro-dosimetric context of grains of similar size. If all the grains were well bleached at deposition, this distribution is assumed to correspond, within uncertainties, with the distribution of equivalent doses (De). The combination of the De and Dr distributions in the De_Dr model proposed here would then al- low calculation of the true depositional age. If grains whose De values are not representative of this age (hereafter called “outliers”) are present in the De distribution, this model al- lows them to be identified before the age is calculated, en- abling their exclusion. As the De_Dr approach relies only on the Dr distribution to describe the De distribution, the model avoids any assumption about the shape of the De distribu- tion, which can be difficult to justify. Herein, we outline the mathematical concepts of the De_Dr approach (more details are given in Galharret et al., 2021) and the exploitation of this Bayesian modelling based on an R code available in the R package “Luminescence”. We also present a series of tests using simulated Dr and De distributions with and without outliers and show that the De_Dr approach can be an alter- native to available models for interpreting De distributions.Using the world in ancient societies : processes and forms of appropriation of space in Long TimeCREDit - Chronological REference Datasets and Sites (CREDit) towards improved accuracy and precision in luminescence-based chronologie

Sedimentary processes and palaeoenvironments from La Combette sequence (southeastern France):Climatic insights on the Last Interglacial/Glacial transition

International audienceDuring the Last Interglacial-Early Glacial transition (MIS5-MIS4; ~73 ka), substantial hydroclimatic changes affected morphogenetic processes, landform dynamics, and ecosystem variability over the Mediterranean sub-alpine valleys. This transition is mainly preserved in the northern Mediterranean region in continuous marine, lacustrine, and peat bog archives. To understand better local-to-regional hydro-sedimentary processes, their climatic significance, and their direct impact on prehistoric settlements, this manuscript reinvestigates a known continental sedimentary record with revised methods. The Middle Palaeolithic site of La Combette in the western Provence region (southeastern France) presents a thick sedimentary key sequence for studying environmental changes from the MIS5 to the MIS3. A review of previous studies with the integration of new micromorphological, sedimentological, physicochemical, malacological, and luminescence ages allows us to characterize the sedimentary processes and environmental patterns during this major climatic transition. Alternating warm and cold conditions and shifting vegetation patterns reflect the strong environmental instability of the end of the Last Interglacial Period. The emergence of a steppe-like ecology dominated by cryo-turbated loess deposition marks the beginning of the Early Würmian Glacial period (MIS4-MIS3; ~73 ka to ~50 ka), contemporaneous with the last Neanderthal occupation at La Combette rock shelter. Comparisons with regional palaeoclimatic data allow us to detail local climatic settings and provide evidence of divergences with larger-scale quantitative reconstructions during a period of significant environmental and socio-cultural shifts

Kinetics of ballistic annihilation and branching

We consider a one-dimensional model consisting of an assembly of two-velocity particles moving freely between collisions. When two particles meet, they instantaneously annihilate each other and disappear from the system. Moreover each moving particle can spontaneously generate an offspring having the same velocity as its mother with probability 1-q. This model is solved analytically in mean-field approximation and studied by numerical simulations. It is found that for q=1/2 the system exhibits a dynamical phase transition. For q<1/2, the slow dynamics of the system is governed by the coarsening of clusters of particles having the same velocities, while for q>1/2 the system relaxes rapidly towards its stationary state characterized by a distribution of small cluster sizes.Comment: 10 pages, 11 figures, uses multicol, epic, eepic and eepicemu. Also avaiable at http://mykonos.unige.ch/~rey/pubt.htm

ICAR: endoscopic skull‐base surgery

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Sexual preferences for songs in female domestic canaries ( Serinus canaria): can late song exposure, without social reinforcement, influence the effects of early tutoring?

We studied the relative effects of early and late song exposure without social reinforcement on female sexual preferences in the domestic canary ( Serinus canaria). Young female canaries were tape-tutored during their first 4 months of life with songs of either domestic or wild male canaries (DT and WT conditions). When they reached sexual maturity, these females were placed in breeding conditions and some of them were re-exposed to songs. During this “late exposure” the females, according to their experimental group, were either presented with new domestic or wild songs (DL and WL conditions) over 40 days, or were kept without song stimulation (- condition). Afterwards, we assessed the sexual preferences of all the females for domestic or wild songs using the copulation solicitation display assay. The results showed that both DT/– and DT/DL females showed a clear preference for domestic songs. However, whereas WT/WL females preferred wild songs; WT/– females did not show any preference. Finally, DT/WL and WT/DL females failed to show any preference. It appeared that a second song experience at the beginning of their first breeding season, without any social reinforcement, allowed the emergence or stabilisation of early preferences, or interfered with these early preferences depending on whether the song category used during the late exposure phase matched or not the song category used during the early tutoring phase, and also depending on which category was used during the first tutoring phase. This behavioural plasticity could help young adult females to adjust the ‘standard’ they built during infancy to new environmental conditions

Comportement et cognition animale : le statut de la stéréotypie et de la variabilité

Voir le comportement pour comprendre le mental ? Imaginons un oiseau qui chante dans un arbre au printemps. Étudier les relations qu'entretient cet animal avec son environnement physique et social nécessite de prendre en compte trois dimensions. Il y a bien sûr une première dimension, facile à objectiver, ce comportement de chant lui-même et les réactions qu'il suscite : parades d'attaque des congénères mâles pour défendre le territoire et attraction, séduction des congénères femelles pour se..

Diversity and diversity specificity of the vocal repertoire of the circl bunting Emberiza cirlus

Analyse de la diversité et la spécificité des chants de cette espèce sans dialectes. Etude des chants atypiques pour comprendre l'autogenèse des chants. Le cas d'un bruant zizi élevé en isolement acoustique permet d'expliquer l'origine de certains chants atypique

La captivité pour socialiser et éduquer l’oiseau chanteur ! De l’intérêt des traités d’élevage des XVIe et XVIIIe siècles pour les éthologues actuels.

International audienceLa captivité pour socialiser et éduquer l'oiseau chanteur ! De l'intérêt des traités d'élevage des XVI e et XVIII e siècles pour les éthologues actuels. Michel KREUTZER 1. in « Aux Sources de l'Histoire Animale » sous la direction de Eric Baratay, éditions de la Sorbonne. 2019, pages 103-113, Partout dans le monde, des oiseaux sont détenus en volière ou en cage pour satisfaire des humains qui apprécient leurs ramage et plumage. En Europe, depuis l'Antiquité, gens de la ville et de la campagne, nobles et bourgeois, se sont approvisionnés en volatiles auprès d'oiseleurs qui les capturaient en nature, ou auprès de commerçants qui les importaient de territoires lointains. Les livres enluminés du Moyen Age comme les peintures et gravures du XVIII e siècle attestent la présence d'oiseaux chanteurs ou parleurs, qui, depuis leur cage et perchoir agrémentent les demeures de leurs vocalisations. Les manuscrits nous apprennent en outre que les humains ne se contentaient pas de les élever et de les écouter pour la seule beauté de leur chant naturel, mais qu'ils les éduquaient également à produire des paroles et des mélodies bien éloignées de leurs vocalisations habituelles. Notons que ces pratiques ne sont pas étrangères au projet plus général qui consistait à conquérir, apprivoiser et domestiquer une nature sauvage, voire à « civiliser » les animaux appelés à vivre dans la proximité ou la demeure des hommes. Les techniques jadis utilisées pour obtenir de ces volatiles des vocalisations singulières intéressent particulièrement les éthologues d'aujourd'hui, car elles mettent en évidence le rôle fondamental des relations sociales lors de l'apprentissage. Chemin faisant, la mise en évidence des contraintes que les éleveurs doivent prendre en compte, les obstacles qu'ils doivent contourner pour parvenir à leurs fins, nous mettent sur la voie d'un « point de vue animal »