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Hantaviruses cause hemorrhagic fever in humans worldwide. However, few hantavirus surveillance campaigns occur in Africa. We detected Seoul orthohantavirus in black rats in Senegal, although we did not find serologic evidence of this disease in humans. These findings highlight the need for increased surveillance of hantaviruses in this region.

Rodents are known to be reservoir hosts for at least 60 zoonotic diseases and are known to play an important role in their transmission and spread in different ways. We sampled different rodent communities within and around human settlements in Northern Senegal, an area subjected to major environmental transformations associated with global changes. Herein, we conducted an epidemiological study on their bacterial communities. One hundred and seventy-one (171) invasive and native rodents were captured, 50 from outdoor trapping sites and 121 rodents from indoor habitats, consisting of five species. The DNA of thirteen pathogens was successfully screened on the rodents' spleens. We found: 2.3% of spleens positive to Piroplasmida and amplified one which gave a potentially new species Candidatus " Theileria senegalensis "; 9.35% of Bartonella spp. and amplified 10, giving three genotypes; 3.5% of filariasis species; 18.12% of Anaplasmataceae species and amplified only 5, giving a new potential species Candidatus " Ehrlichia senegalensis "; 2.33% of Hepatozoon spp.; 3.5% of Kinetoplastidae spp.; and 15.2% of Borrelia spp. and amplified 8 belonging all to Borrelia crocidurae. Some of the species of pathogens carried by the rodents of our studied area may be unknown because most of those we have identified are new species. In one bacterial taxon, Anaplasma , a positive correlation between host body mass and infection was found. Overall, male and invasive rodents appeared less infected than female and native ones, respectively.

Mandarin-speaking adults using cochlear implants (CI) experience more difficulties in perceiving lexical tones than consonants. This problem may result from the fact that CIs provide relatively sufficient temporal envelope information for consonant perception in quiet environments, but do not convey the fine spectro-temporal information considered to be necessary for accurate pitch perception. Another possibility is that Mandarin speakers with post-lingual hearing loss have developed language-specific use of these acoustic cues, impeding lexical tone processing under CI conditions. To investigate this latter hypothesis, syllable discrimination and word identification abilities for Mandarin consonants (place and manner) and lexical-tone contrasts (tones 1 vs 3 and 1 vs 2) were measured in 15 Mandarin-speaking children using CIs and age-matched children with normal hearing (NH). In the discrimination task, only children using CIs exhibited significantly lower scores for consonant place contrasts compared to other contrasts, including lexical tones. In the word identification task, children using CIs showed lower performance for all contrasts compared to children with NH, but they both showed specific difficulties with tone 1 vs 2 contrasts. This study suggests that Mandarin-speaking children using CIs are able to discriminate and identify lexical tones and, perhaps more surprisingly, have more difficulties when discriminating consonants.

The crawling behavior of sixty 2-day-old newborns was studied while they were supported prone on a mini skateboard and on a pediatric mattress without additional support. Analyses of the number and types of limb movements and their characteristics, the coactivation of limb pairs, and the displacement across the surface, revealed that newborns can crawl with locomotor patterns similar to those documented during quadrupedal locomotion in animals and human adults. This was particularly apparent on the skateboard. This discovery suggests that locomotor circuitry underlying quadrupedal locomotion develops during fetal life. Drawing upon other evidence for a quadrupedal organization underlying bipedal gait, we argue that early quadrupedal training may enhance interventions designed to hasten the onset of independent walking., (© 2019 Society for Research in Child Development.)

A variety of studies have shown differences between phonetic features of consonants according to their prosodic and/or syllable (onset vs. coda) positions. However, differences are not always found, and interactions between the various factors involved are complex and not well understood. Our study compares acoustical characteristics of coda consonants in Vietnamese taking into account their position within words. Traditionally described as monosyllabic, Vietnamese is partially polysyllabic at the lexical level. In this language, tautosyllabic consonant sequences are prohibited, and adjacent consonants are only found at syllable boundaries either within polysyllabic words (CVC.CVC) or across monosyllabic words (CVC#CVC). This study is designed to examine whether or not syllable boundary types (interword vs. intraword) have an effect on the acoustic realization of codas. The results show significant acoustic differences in consonant realizations according to syllable boundary type, suggesting different coarticulation patterns between nuclei and codas. In addition, as Vietnamese voiceless stops are generally unreleased in coda position, with no burst to carry consonantal information, our results show that a vowel's second half contains acoustic cues which are available to aid in the discrimination of place of articulation of the vowel's following consonant., (© 2018 S. Karger AG, Basel.)

The Biological Resource Centre for the Environment BRC4Env is a network of Biological Resource Centres (BRCs) and collections whose leading objectives are to improve the visibility of genetic and biological resources maintained by its BRCs and collections and to facilitate their use by a large research community, from agriculture research to life sciences and environmental sciences. Its added value relies on sharing skills, harmonizing practices, triggering projects in comparative biology, and ultimately proposing a single-entry portal to facilitate access to documented samples, taking into account the partnership policies of research institutions as well as the legal frame which varies with the biological nature of resources. BRC4Env currently includes three BRCs: the Centre for Soil Genetic Resources of the platform GenoSol, in partnership with the European Conservatory of Soil Samples; the Egg Parasitoids Collection (EP-Coll); and the collection of ichthyological samples, Colisa. BRC4Env is also associated to several biological collections: microbial consortia (entomopathogenic bacteria, freshwater microalgae…), terrestrial arthropods, nematodes (plant parasitic, entomopathogenic, animal parasitic...), and small mammals. The BRCs and collections of BRC4Env are involved in partnership with academic scientists, as well as private companies, in the fields of medicinal mining, biocontrol, sustainable agriculture, and additional sectors. Moreover, the staff of the BRCs is involved in many training courses for students from French licence degree to Ph.D, engineers, as well as ongoing training.

Murid rodents (Rodentia: Muridae) represent the most diverse and abundant mammalian family. In this study, we provide a refined set of fossil calibrations which is used to reconstruct a dated phylogeny of the family using a multilocus dataset (six nuclear and nine mitochondrial gene fragments) encompassing 161 species representing 82 murid genera from four extant subfamilies (Deomyinae, Gerbillinae, Lophiomyinae and Murinae). In comparison with previous studies on murid or muroid rodents, our work stands out for the implementation of nine robust fossil constraints within the Muridae thanks to a thorough review of the fossil record. Before being assigned to specific nodes of the phylogeny, all potential fossil constraints were carefully assessed; they were also subjected to several cross-validation analyses. The resulting phylogeny is consistent with previous phylogenetic studies on murids, and recovers the monophyly of all sampled murid subfamilies and tribes. Based on nine controlled fossil calibrations, our inferred temporal timeframe indicates that the murid family likely originated in the course of the Early Miocene, 22.0-17.0 million years ago (Ma), and that most major lineages (i.e. tribes) started diversifying ca. 10 Ma. Historical biogeography analyses support the tropical origin for the family, with an initial internal split (vicariance event) between Afrotropical and Oriental (Indomalaya and Philippines) lineages. During the course of their diversification, the biogeographic pattern of murids is marked by several dispersal events toward the Australasian and the Palearctic regions. The Afrotropical region was also secondarily colonized at least three times from the Indomalaya, indicating that the latter region has acted as a major centre of diversification for the family., (Copyright © 2018. Published by Elsevier Inc.)

[This corrects the article DOI: 10.1016/j.nmni.2018.03.005.].

Humans considerably vary in the degree to which they rely on their peers to make decisions. Why? Theoretical models predict that environmental risks shift the cost-benefit trade-off associated with the exploitation of others' behaviours (public information), yet this idea has received little empirical support. Using computational analyses of behaviour and multivariate decoding of electroencephalographic activity, we test the hypothesis that perceived vulnerability to extrinsic morbidity risks impacts susceptibility to social influence, and investigate whether and how this covariation is reflected in the brain. Data collected from 261 participants tested online revealed that perceived vulnerability to extrinsic morbidity risks is positively associated with susceptibility to follow peers' opinion in the context of a standard face evaluation task. We found similar results on 17 participants tested in the laboratory, and showed that the sensitivity of EEG signals to public information correlates with the participants' degree of vulnerability. We further demonstrated that the combination of perceived vulnerability to extrinsic morbidity with decoding sensitivities better predicted social influence scores than each variable taken in isolation. These findings suggest that susceptibility to social influence is partly calibrated by perceived environmental risks, possibly via a tuning of neural mechanisms involved in the processing of public information.

This study focuses on how the body schema develops during the first months of life, by investigating infants' motor responses to localized vibrotactile stimulation on their limbs. Vibrotactile stimulation was provided by small buzzers that were attached to the infants' four limbs one at a time. Four age groups were compared cross-sectionally (3-, 4-, 5-, and 6-month-olds). We show that before they actually reach for the buzzer, which, according to previous studies, occurs around 7-8 months of age, infants demonstrate emerging knowledge about their body's configuration by producing specific movement patterns associated with the stimulated body area. At 3 months, infants responded with an increase in general activity when the buzzer was placed on the body, independently of the vibrator's location. Differentiated topographical awareness of the body seemed to appear around 5 months, with specific responses resulting from stimulation of the hands emerging first, followed by the differentiation of movement patterns associated with the stimulation of the feet. Qualitative analyses revealed specific movement types reliably associated with each stimulated location by 6 months of age, possibly preparing infants' ability to actually reach for the vibrating target. We discuss this result in relation to newborns' ability to learn specific movement patterns through intersensory contingency. Statement of contribution what is already known on infants' sensorimotor knowledge about their own bodies 3-month-olds readily learn to produce specific limb movements to obtain a desired effect (movement of a mobile). infants detect temporal and spatial correspondences between events involving their own body and visual events. what the present study adds until 4-5 months of age, infants mostly produce general motor responses to localized touch. this is because in the present study, infants could not rely on immediate contingent feedback. we propose a cephalocaudal developmental trend of topographic differentiation of body areas., (© 2017 The Authors British Journal of Developmental Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

The dynamic attending theory proposes that rhythms entrain periodic fluctuations of attention which modulate the gain of sensory input. However, temporal expectancies can also be driven by the mere passage of time (foreperiod effect). It is currently unknown how these two types of temporal expectancy relate to each other, i.e. whether they work in parallel and have distinguishable neural signatures. The current research addresses this issue. Participants either tapped a 1Hz rhythm (active task) or were passively presented with the same rhythm using tactile stimulators (passive task). Based on this rhythm an auditory target was then presented early, in synchrony, or late. Behavioural results were in line with the dynamic attending theory as RTs were faster for in- compared to out-of-synchrony targets. Electrophysiological results suggested self-generated and externally induced rhythms to entrain neural oscillations in the delta frequency band. Auditory ERPs showed evidence of two distinct temporal expectancy processes. Both tasks demonstrated a pattern which followed a linear foreperiod effect. In the active task, however, we also observed an ERP effect consistent with the dynamic attending theory. This study shows that temporal expectancies generated by a rhythm and expectancy generated by the mere passage of time can work in parallel and sheds light on how these mechanisms are implemented in the brain., (Copyright © 2017 Elsevier Inc. All rights reserved.)

There are two main factors explaining variation among species and the evolution of characters along phylogeny: adaptive change, including phenotypic and genetic responses to selective pressures, and phylogenetic inertia, or the resemblance between species due to shared phylogenetic history. Phenotype-habitat colour match, a classic Darwinian example of the evolution of camouflage (crypsis), offers the opportunity to test the importance of historical versus ecological mechanisms in shaping phenotypes among phylogenetically closely related taxa. To assess it, we investigated fur (phenotypic data) and habitat (remote sensing data) colourations, along with phylogenetic information, in the species-rich Gerbillus genus. Overall, we found a strong phenotype-habitat match, once the phylogenetic signal is taken into account. We found that camouflage has been acquired and lost repeatedly in the course of the evolutionary history of Gerbillus. Our results suggest that fur colouration and its covariation with habitat is a relatively labile character in mammals, potentially responding quickly to selection. Relatively unconstrained and substantial genetic basis, as well as structural and functional independence from other fitness traits of mammalian colouration might be responsible for that observation.

As soon as infants grasp objects, they exhibit some degree of hand preference. Although all studies agree that the number of non-lateralized infants remains high during the first months of life, there is no consensus on the percentage of right- and left-handed infants. Reasons might be the different formulae used to calculate an handedness index, the basis on which handedness categories are distinguished, and the number of trials per session. In this study we aimed to provide a valid method of testing handedness, reliable without being lengthy so as to combine it with other evaluations. We tested 46 infants at 9 and 11 months by giving them 34 trials. We compared the results using 2 of the most used formulae, including the bimanual grasps or not, and considering the first 5, 10, 15, 20, 26, 31, or all 34 trials. The results show that different formulae do not give significantly different results as long as bimanual grasps are included. The number of trials is important: 15 trials are necessary for the reliability of the classification into handedness categories. Giving more trials does not provide substantial additional information.

By the end of their first year of life, infants' representations of familiar words contain phonetic detail; yet little is known about the nature of these representations at the very beginning of word learning. Bouchon et al. () showed that French-learning 5-month-olds could detect a vowel change in their own name and not a consonant change, but also that infants reacted to the acoustic distance between vowels. Here, we tested British English-learning 5-month-olds in a similar study to examine whether the acoustic/phonological characteristics of the native language shape the nature of the acoustic/phonetic cues that infants pay attention to. In the first experiment, British English-learning infants failed to recognize their own name compared to a mispronunciation of initial consonant (e.g., Molly versus Nolly) or vowel (e.g., April versus Ipril). Yet in the second experiment, they did so when the contrasted name was phonetically dissimilar (e.g., Sophie versus Amber). Differences in phoneme category (stops versus continuants) between the correct consonant versus the incorrect one significantly predicted infants' own name recognition in the first experiment. Altogether, these data suggest that infants might enter into a phonetic mode of processing through different paths depending on the acoustic characteristics of their native language., (Copyright © International Congress of Infant Studies (ICIS).)

Wesselsbron disease is a neglected mosquito transmitted Flavivirus infection that causes abortions and has teratogenic effects on sheep and cattle in Africa. Human can also be infected. The detection of human or animal cases is complicated by the non-specific symptoms close to Rift Valley Fever (RVF) in domestic livestock species or Dengue like syndrome in humans. Then, these detections are usually made during RVF investigations in sheep. These domestic animals should take a role in the life cycle of the virus but some evidences of Wesselsbron virus (WSLV) presence in wild animals suggest that the latter may be involved in the virus maintenance in nature. However, the reservoir status of wild vertebrate in general and rodents particularly for WSLV is only based on an isolation from a Cape short-eared gerbil in southern Africa. Most of WSLV isolations are from southern parts of Africa even if it has been found in western and central Africa or Madagascar. In Senegal, there are serological evidences of WSLV circulation in human since the 1970s and some isolations, the last one of which dates back in 1992. Despite the detection of the virus on mosquitoes until the 2000s in different parts of the country, no new human case has been noted. In this paper, we report the WSLV re-emergence in eastern Senegal in 2013 with 2 human cases and its first isolation from a black rat Rattus rattus . Sequencing analyses show the circulation of the same strain between these humans and the commensal rodent. The putative impact on WSLV transmission to human populations could be more important if the reservoir status of the black rat is confirmed. Focused survey in human populations, specific entomological and mammalogical investigations would permit a better understanding of the life cycle of the virus and its impact on public health.

The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

In the contemporary context of zoonosis emergence and spread, invasive species are a major issue since they represent potential pathogen hosts. Even though many progresses have been done to understand and predict spatial patterns of invasive species, the challenge to identify the underlying determinants of their distribution remains a central question in invasion biology. This is particularly exacerbated in the case of commensal species that strictly depend on humankind for dispersal and perennial establishment of new populations. The distribution of these species is predicted to be influenced by dispersal opportunities and conditions acting on establishment and proliferation, such as environmental characteristics, including spatio-temporal components of the human societies. We propose to contribute to the understanding of the recent spread of a major invasive rodent species, the black rat (Rattus rattus), in the changing southeastern of Senegal. We address the factors that promote the dispersal and distribution of this invasive rodent from the perspective of human geography. We first describe characteristics of human settlements in terms of social and spatial organization of human societies (i.e. economic activities, commercial and agricultural networks, roads connectivity). We then explore the relationship between these characteristics and the distribution of this invasive rodent. Finally we propose that historical and contemporary dynamics of human societies have contributed to the risk of invasion of the black rat. We argue that the diffusion processes of invasive species cannot be considered as a result of the spatial structure only (i.e. connectivity and distance), but as a part of the human territory that includes the social and spatial organization. Results suggest that the distribution of invasive rodents partly results from the contemporary and inherited human socio-spatial systems, beyond the existence of suitable ecological conditions that are classically investigated by biologists., Competing Interests: The authors have declared that no competing interests exist.

The present study examines the effect of language experience on vocal emotion perception in a second language. Native speakers of French with varying levels of self-reported English ability were asked to identify emotions from vocal expressions produced by American actors in a forced-choice task, and to rate their pleasantness, power, alertness and intensity on continuous scales. Stimuli included emotionally expressive English speech (emotional prosody) and non-linguistic vocalizations (affect bursts), and a baseline condition with Swiss-French pseudo-speech. Results revealed effects of English ability on the recognition of emotions in English speech but not in non-linguistic vocalizations. Specifically, higher English ability was associated with less accurate identification of positive emotions, but not with the interpretation of negative emotions. Moreover, higher English ability was associated with lower ratings of pleasantness and power, again only for emotional prosody. This suggests that second language skills may sometimes interfere with emotion recognition from speech prosody, particularly for positive emotions.

Methodological improvements now allow routine analyses of highly degraded DNA samples as found in museum specimens. Using these methods could be useful in studying such groups as rodents of the genus Gerbillus for which i) the taxonomy is still highly debated, ii) collection of fresh specimens may prove difficult. Here we address precise taxonomic questions using a small portion of the cytochrome b gene obtained from 45 dry skin/skull museum samples (from 1913 to 1974) originating from two African and three Asian countries. The specimens were labelled Gerbillus gerbillus, Gerbillus andersoni, Gerbillus nanus, Gerbillus amoenus, Gerbillus perpallidus and Gerbillus pyramidum, and molecular results mostly confirmed these assignations. The close relationship between Gerbillus nanus (Asian origin) and Gerbillus amoenus (African origin) confirmed that they represent vicariant sibling species which differentiated in allopatry on either side of the Red Sea. In the closely related Gerbillus perpallidus and Gerbillus pyramidum, specimens considered as belonging to one Gerbillus pyramidum subspecies (Gerbillus pyramidum floweri) appeared closer to Gerbillus perpallidus suggesting that they (Gerbillus pyramidum floweri and Gerbillus perpallidus) may represent a unique species, distributed on both sides of the Nile River, for which the correct name should be Gerbillus floweri. Furthermore, the three other Gerbillus pyramidum subspecies grouped together with no apparent genetic structure suggesting that they may not yet represent genetically differentiated lineages. This study confirms the importance of using these methods on museum samples, which can open new perspectives in this particular group as well as in other groups of interest.

Tick-borne relapsing fever (TBRF) is a zoonotic disease caused by several Borrelia species transmitted to humans by Ornithodoros tick vectors. In West Africa, Borrelia crocidurae is a common cause of disease in many rural populations. Small mammals act as reservoirs of infection. We report here the results of surveys that investigated the occurrence of B. crocidurae infection in rodents and insectivores from eight countries of West and Central Africa. Animals were identified at the species level and tested for Borrelia either by examination of thick blood film, intra-peritoneal inoculation of blood or brain tissues into laboratory mice, or by molecular techniques. A total of 4358 small mammals belonging to 38 species and 7 families were collected, including 3225 specimens collected in areas where the occurrence of Ornithodoros sonrai tick in rodent burrows was documented, and 1133 in areas where this tick was absent. In areas with O. sonrai, Borrelia infection was demonstrated in 287 of 3109 (9.2%) small mammals tested, and none was documented in 1004 animals tested from other areas. There was no relationship between the occurrence of Rhipicephalus, Hyaloma and Argas ticks in burrows and the distribution of Borrelia infection in small mammals. The 287 specimens infected by Borrelia belonged to 15 rodent and shrew species, including three Saharo-Sahelian species - Gerbillus gerbillus, Gerbillus occiduus and Gerbillus tarabuli - identified as reservoirs for TBRF with a distribution restricted to this area. In Sudan and Sudano-Sahelian areas, Arvicanthis niloticus, Mastomys erythroleucus and Mastomys huberti were the main reservoir of infection. Although most small mammals species collected had a large distribution in West and Central Africa, the fact that only animals collected in areas with O. sonrai were found infected suggest that this tick is the only vector of TBRF in rodents and insectivores in this part of Africa., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Recent studies about the implicit causality of inter-personal verbs showed a symmetric implicit consequentiality bias for psychological verbs. This symmetry is less clear for action verbs because the verbs assigning the implicit cause to the object argument (e.g. "Peter protected John because he was in danger.") tend to assign the implicit consequence to the same argument (e.g. "Peter protected John so he was not hurt."). We replicated this result by comparing continuations of inter-personal events followed by a causal connective "because" or a consequence connective "so". Moreover, we found similar results when the consequence connective was replaced by a contrastive connective "but". This result was confirmed in a second experiment where we measured the time required to imagine a consistent continuation for a fragment finishing with "but s/he ...". The results were consistent with a contrastive connective introducing a denial of a consequence of the previous event. The results were consistent with a model suggesting that thematic roles and connectives can predict preferred co-reference relations.

Background: Relapsing fever is the most frequent bacterial disease in Africa. Four main vector / pathogen complexes are classically recognized, with the louse Pediculus humanus acting as vector for B. recurrentis and the soft ticks Ornithodoros sonrai, O. erraticus and O. moubata acting as vectors for Borrelia crocidurae, B. hispanica and B. duttonii, respectively. Our aim was to investigate the epidemiology of the disease in West, North and Central Africa., Methods and Findings: From 2002 to 2012, we conducted field surveys in 17 African countries and in Spain. We investigated the occurrence of Ornithodoros ticks in rodent burrows in 282 study sites. We collected 1,629 small mammals that may act as reservoir for Borrelia infections. Using molecular methods we studied genetic diversity among Ornithodoros ticks and Borrelia infections in ticks and small mammals. Of 9,870 burrows investigated, 1,196 (12.1%) were inhabited by Ornithodoros ticks. In West Africa, the southern and eastern limits of the vectors and Borrelia infections in ticks and small mammals were 13°N and 01°E, respectively. Molecular studies revealed the occurrence of nine different Ornithodoros species, including five species new for science, with six of them harboring Borrelia infections. Only B. crocidurae was found in West Africa and three Borrelia species were identified in North Africa: B. crocidurae, B. hispanica, and B. merionesi., Conclusions: Borrelia Spirochetes responsible for relapsing fever in humans are highly prevalent both in Ornithodoros ticks and small mammals in North and West Africa but Ornithodoros ticks seem absent south of 13°N and small mammals are not infected in these regions. The number of Ornithodoros species acting as vector of relapsing fever is much higher than previously known.

A phylogeographic study was conducted on the Nile grass rat, Arvicanthis niloticus, a rodent species that is tightly associated with open grasslands from the Sudano-Sahelian regions. Using one mitochondrial (cytochrome b) and one nuclear (intron 7 of Beta Fibrinogen) gene, robust patterns were retrieved that clearly show that (i) the species originated in East Africa concomitantly with expanding grasslands some 2 Ma, and (ii) four parapatric and genetically well-defined lineages differentiated essentially from East to West following Pleistocene bioclimatic cycles. This strongly points towards allopatric genetic divergence within savannah refuges during humid episodes, then dispersal during arid ones; secondary contact zones would have then stabilized around geographic barriers, namely, Niger River and Lake Chad basins. Our results pertinently add to those obtained for several other African rodent as well as non-rodent species that inhabit forests, humid zones, savannahs and deserts, all studies that now allow one to depict a more comprehensive picture of the Pleistocene history of the continent south of the Sahara. In particular, although their precise location remains to be determined, at least three Pleistocene refuges are identified within the West and Central African savannah biome.

A new species of the genus Oxynema Linstow 1899, is described from the African sciurids Xerus erythropus and Heliosciurus gambianus. Oxynema xerusi n. sp. is characterized by the lack of cervical and caudal alae and by having unequal spicules. It differs from the closest species, Oxynema linstowi Deshmukh, 1987 and Oxynema bioccai Campana-Rouget, 1956, by the number, shape, and distribution of the caudal papillae, the length of the spicules, and the ratio of spicule length to body length.

Auditory and somatosensory systems play a key role in speech motor control. In the act of speaking, segmental speech movements are programmed to reach phonemic sensory goals, which in turn are used to estimate actual sensory feedback in order to further control production. The adult's tendency to automatically imitate a number of acoustic-phonetic characteristics in another speaker's speech however suggests that speech production not only relies on the intended phonemic sensory goals and actual sensory feedback but also on the processing of external speech inputs. These online adaptive changes in speech production, or phonetic convergence effects, are thought to facilitate conversational exchange by contributing to setting a common perceptuo-motor ground between the speaker and the listener. In line with previous studies on phonetic convergence, we here demonstrate, in a non-interactive situation of communication, online unintentional and voluntary imitative changes in relevant acoustic features of acoustic vowel targets (fundamental and first formant frequencies) during speech production and imitation. In addition, perceptuo-motor recalibration processes, or after-effects, occurred not only after vowel production and imitation but also after auditory categorization of the acoustic vowel targets. Altogether, these findings demonstrate adaptive plasticity of phonemic sensory-motor goals and suggest that, apart from sensory-motor knowledge, speech production continuously draws on perceptual learning from the external speech environment.

Pterygodermatites (Mesopectines) quentini n. sp. (Nematoda, Rictulariidae) is described from the murine host Praomys rostratus in the south of the Republic of Mali. It differs from other species of the subgenus by the morphology of the head, which bears four simple cephalic papillae and a nearly axial oral opening, the number of caudal papillae, the number of precloacal cuticular formations, unequal spicules and the ratio of spicule lengths/body length. The use of scanning electron microscopy in combination with conventional light microscopy enabled us to give a detailed description of the morphological characters of this new species., (© M. Diouf et al., published by EDP Sciences, 2013.)

Knowledge of the biology of the trichinelloid subfamily Trichosomoidinae is poor. Trichosomoides nasalis is a common parasite of Arvicanthis niloticus (Muridae) in Senegal, and a procedure for experimental infections has been established. It has been demonstrated that larvae develop in striated muscle fibres, similar to Trichinella spp., but they are not arrested in the first stage, and they reach the adult stage within three weeks. In the present histological study it is shown that T. nasalis females and dwarf males migrate from the abdomen and thorax to the host's muzzle, moving through connective tissues and between muscles. A few migrating specimens were also found in the blood vessels of the nasal mucosa. While sexes were still separated in the lamina propria of the mucosa, females recovered from the epithelium contained intra-uterine males. Worms were found between the incisors in the mucosa of the anterior and median conchae which are rich in mucous cells. Only the pseudostratified epithelium was parasitized. Under natural conditions, the inflammation of the nasal mucosa that is induced by the parasites might reduce the competitiveness of infected rodents when foraging or looking for potential mates.

Background: The presence in Morocco of Argasid ticks of the Ornithodoros erraticus complex, the vector of tick-borne relapsing fever (TBRF) in North Africa, has been known since 1919, but the disease is rarely diagnosed and few epidemiological data are available., Methodology/principal Findings: Between 2006 and 2011, we investigated the presence of Ornithodoros ticks in rodent burrows in 34 sites distributed across Morocco. We also collected small mammals in 10 sites and we investigated TBRF in febrile patients in Kenitra district. The prevalence of Borrelia infections was assessed by nested PCR amplification in ticks and the brain tissue of small mammals, and by evaluation of thick blood films in patients. A high proportion of burrows were infested with ticks of the O. erraticus complex in all regions of Morocco, with a mean of 39.5% for the whole country. Borrelia infections were found in 39/382 (10.2%) of the ticks and 12/140 (8.6%) of the rodents and insectivores studied by PCR amplification, and 102 patients tested positive by thick blood film. Five small mammalian species were found infected: Dipodillus campestris, Meriones shawi, Gerbillus hoogstrali, Gerbillus occiduus and Atelerix algirus. Three Borrelia species were identified in ticks and/or rodents: B. hispanica, B. crocidurae and B. merionesi., Conclusions/significance: Tick populations belonging to O. erraticus complex are widely distributed in Morocco and a high proportion of ticks and small mammals are infected by Borrelia species. Although rarely diagnosed, TBRF may be a common cause of morbidity in all regions of Morocco.

This article documents the addition of 277 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Ascochyta rabiei, Cambarellus chapalanus, Chionodraco hamatus, Coptis omeiensis, Cynoscion nebulosus, Daphnia magna, Gerbillus nigeriae, Isurus oxyrinchus, Lates calcarifer, Metacarcinus magister, Oplegnathus fasciatus, Pachycondyla verenae, Phaethon lepturus, Pimelodus grosskopfii, Rotylenchulus reniformis, Scomberomorus niphonius, Sepia esculenta, Terapon jarbua, Teratosphaeria cryptica and Thunnus obesus. These loci were cross-tested on the following species: Austropotamobius italicus, Cambarellus montezumae, Cambarellus puer, Cambarellus shufeldtii, Cambarellus texanus, Chionodraco myersi, Chionodraco rastrospinosus, Coptis chinensis, Coptis chinensis var. brevisepala, Coptis deltoidea, Coptis teeta, Orconectes virilis, Pacifastacus leniusculus, Pimelodus bochii, Procambarus clarkii, Pseudopimelodus bufonius, Rhamdia quelen, Sepia andreana, Sepiella maindroni, Thunnus alalunga, Thunnus albacares, Thunnus maccoyii, Thunnus orientalis, Thunnus thynnus and Thunnus tonggol., (© 2011 Blackwell Publishing Ltd.)

This experiment was designed to explore the impact of age and amount of retrieval support on episodic memory and its electrophysiological correlates. Event-related potentials (ERPs) were recorded while young and older participants performed a word-stem cued-recall task in a low-support condition (LSC) in which the stem was composed of three letters, and a high-support condition (HSC) in which the cue consisted of four letters. Behavioral analyses showed that recall in the older group was less accurate than in the young group in the LSC, but no age differences were observed in the HSC. In the LSC, old/new ERP effects at frontal and parietal sites were later and less sustained for the older adults. Furthermore, the parietal old/new effect was symmetrically distributed for older adults, whereas it was predominant over the left hemisphere for their younger counterparts. In addition, young participants demonstrated early and long-lasting frontal and parietal effects in the HSC but with predominance over the right hemisphere, whereas the older adults exhibited a frontal effect and an early and long-lasting parietal effect becoming predominant over the left hemisphere. No age differences in the time course of the parietal old/new effect were observed in this more supportive condition. In addition, in the last period, the left parietal effect was greater for the older group. This study suggests that episodic memory performance and ERP correlates of recall processes are more similar between young and older adults when increased support is provided at retrieval., (Copyright 2010 Elsevier B.V. All rights reserved.)

The karyotypes of the lesser Egyptian jerboa Jaculus jaculus and the greater Egyptian jerboa Jaculus orientalis from Tunisia are described and compared with available data particularly from Egypt. The species examined have a similar karyotype consisting of 2n = 48 chromosomes and a fundamental number of autosomes (NFa) varying from 88 to 90 in J. jaculus and from 84 to 88 in J. orientalis. The X chromosome is submetacentric in both species, while the Y is submetacentric in J. orientalis and acrocentric in J. jaculus. Most of the autosomes are meta/submetacentric but the small pairs 22 - 23 in J. jaculus and 20-23 in J. orientalis are frequently acrocentric, yielding considerable differences in the NFa within and among species. Morphological variation in these small pairs of autosomes and/or in the Y chromosome in J. orientalis may distinguish populations of the two species from Egypt and Tunisia. The differences observed either between Egypt and Tunisia or between the Tunisian Jaculus species are probably associated with chromosomal rearrangements such as pericentric inversions or heterochromatin variation. They appear of lesser magnitude than other changes (especially molecular) that have occurred during the evolution of this genus.

This article documents the addition of 238 microsatellite marker loci and 72 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Adelges tsugae, Artemisia tridentata, Astroides calycularis, Azorella selago, Botryllus schlosseri, Botrylloides violaceus, Cardiocrinum cordatum var. glehnii, Campylopterus curvipennis, Colocasia esculenta, Cynomys ludovicianus, Cynomys leucurus, Cynomys gunnisoni, Epinephelus coioides, Eunicella singularis, Gammarus pulex, Homoeosoma nebulella, Hyla squirella, Lateolabrax japonicus, Mastomys erythroleucus, Pararge aegeria, Pardosa sierra, Phoenicopterus ruber ruber and Silene latifolia. These loci were cross-tested on the following species: Adelges abietis, Adelges cooleyi, Adelges piceae, Pineus pini, Pineus strobi, Tubastrea micrantha, three other Tubastrea species, Botrylloides fuscus, Botrylloides simodensis, Campylopterus hemileucurus, Campylopterus rufus, Campylopterus largipennis, Campylopterus villaviscensio, Phaethornis longuemareus, Florisuga mellivora, Lampornis amethystinus, Amazilia cyanocephala, Archilochus colubris, Epinephelus lanceolatus, Epinephelus fuscoguttatus, Symbiodinium temperate-A clade, Gammarus fossarum, Gammarus roeselii, Dikerogammarus villosus and Limnomysis benedeni. This article also documents the addition of 72 sequencing primer pairs and 52 allele specific primers for Neophocaena phocaenoides., (© 2009 Blackwell Publishing Ltd.)

Objective: Warning signals can induce a paradoxical increase in reaction time (RT) when detecting targets. Top-down inhibitory control intended to prevent undesired responses to non-target stimuli may account for this effect. This hypothesis assumes the existence of a gating mechanism during conditions of uncertainty that locks the initiation of movement before any stimulus is presented and thus increases the RT to any targets that are not preceded by warning cues. However, direct evidence for the involvement of inhibitory mechanisms in the paradoxical warning effect is still lacking., Methods: Event-related potentials (ERPs) were analyzed by means of a target detection task according to two experimental protocols: one requiring inhibition (warned and unwarned trials mixed in the same block) and the other not requiring inhibition (warned and unwarned trials separated into different blocks)., Results: The probability that warning signals would be introduced in a block (mixed-block design) dramatically increased RT to unwarned targets and evoked target-locked markers of inhibition in these trials (N2 was evoked and P3 was delayed). Cue-locked ERPs also exhibited a strong N2 component whatever the design., Conclusions: The top-down control implemented in the pre-stimulus period to prevent undesired automatic responses to external events inhibits the triggering of movement., Significance: Understanding this gating mechanism may provide insight into various neurological or psychiatric disorders affecting movement initiation, such as akinesia or impulsivity that may both be viewed as disorders of higher order inhibitory control.

This experiment investigated age differences in electrophysiological correlates of retrieval success in a word-stem cued recall task. Young adults (M+/-SD: 21.4 years+/-1.9) performed this memory task more accurately than older participants (M+/-SD: 65.1 years+/-3.3). Robust event-related brain potential (ERP) old/new effects were identified in both age groups. The main age differences were observed in latency and lateralization of ERP effects. Young adults exhibited a parietal effect that became focused over left parietal electrodes, whereas no asymmetry was observed in older adults. Moreover, ERP effects were more delayed in the older group. Overall, these findings provide some evidence of the reduction of processing speed during aging and suggest that young and older adults may recruit distinct cerebral patterns during episodic cued recall.

Typical simple reaction-time (RT) paradigms usually include a warning signal followed by a variable foreperiod before the presentation of a reaction stimulus. Most current interpretations suggest that the warning stimulus alerts the organism and so results in faster processing of either the sensory or motor components of the task. In this study, electromyography (EMG) was used to detect both covert and overt motor errors in a simple warned RT task. Results show that warning signals may trigger automatic motor activations that are likely to cause false alarms. Distribution analysis reveals that 77% of all errors detected with EMG are erroneous responses to the warning signal. Accordingly, we propose that movement triggering needs to be temporarily inhibited before the stimulus to prevent premature responses during the foreperiod. This proactive inhibition would be responsible for a paradoxical increase in RT for conditions with short foreperiods compared with control conditions in which no warning signal is presented. These results call for a reassessment of the theoretical framework used to interpret the effects of warning signals.

The multimammate rat Mastomys huberti is a Sahelian species restricted to West Africa. Throughout its distribution area, the species is associated with humid habitats, flood plains and ponds, which make its current distribution highly fragmented. Knowing that humid and dry climatic phases regularly alternated along the Quaternary in West Africa, it can be postulated that the evolutionary history of the species and its genetic variation largely reflect these climatic oscillations. We used mitochondrial cytochrome b sequences to investigate the phylogenetic relationships of M. huberti populations across the totality of the species' geographical range (Mali, Senegal, Guinea and Mauritania). We found that cytochrome b sequence variation is partitioned into four divergent clades (mean Kimura 2-parameter genetic distances varying from 0.57 to 3.08%) corresponding to distinct geographical regions. We dated the separation events of these clades between 0.93 and 0.17 million years ago, suggesting that M. huberti history was strongly influenced by the Quaternary climatic variations and related hydrographic network changes. Relationships between lineages and the partitioning of genetic diversity suggest the occurrence of two refuges along the Atlantic coast during arid periods. Moreover, the species' current range results from a stepwise colonization from west to east. M. huberti colonized recently the Inner Delta of Niger River in Mali, probably during a humid episode some 0.6 million years ago. Demographically stable and highly diversified populations were found in South Senegal and Guinea while populations in North Senegal and in Mali experienced low numbers followed by a demographic expansion during the African Humid Period (c. 14 800-5500 bp). During the last arid period (c. 23 000-18 000 years ago), Malian populations found refuge in the northern parts of the Inner Delta of the Niger River, then expended to the southern parts of the delta and along the course of the Niger River downstream Tombouctou. More recently, M. huberti would have rapidly expanded into irrigated areas along the Senegal River and along the Canal du Sahel, Mali, reflecting the invasive and the pest character of this species.

Ocular torsion is a key problem in the understanding of many visual perceptual effects. However, since it is difficult to record, its integration with other sensorimotor signals is still poorly understood. Unfortunately, eyetracker systems are generally not dedicated to the monitoring of eye torsion. In addition, the classical methods used with video-based systems present some limits in the accuracy of torsion calculation. These limits are especially related to the detection of pupil center and the effects of pupil size changes. This article aims at (1) proposing a solution to analyze ocular torsion together with head roll using EyeLink II or similar equipment, (2) reviewing and adapting classical polar cross-correlation methods in order to improve the accuracy of torsion measurement, (3) providing a lower-cost method compared with the existing ones. Video sequences issued from the EyeLink II host computer monitor were recorded by means of a second computer equipped with a video acquisition card and converted into image sequences. Images were analyzed with algorithms of pupil center detection (median-based algorithm), torsion analysis (adapted polar cross-correlation method which takes into account pupil size variations) and marker tracking (head roll analysis). This method was tested on virtual eye images. Results are discussed with respect to other algorithms found in the literature.

Gerbilliscus has recently been proposed as an endemic African rodent genus distinct from the Asian Tatera. A molecular phylogeny of the genus, including nine species from southern, western and eastern Africa, is presented here based on the analysis of the cytochrome b and 16S mitochondrial genes. With an adequate taxonomic sampling over a wide geographic range, we here provide a clear picture of the phylogenetic relationships between species and species groups in this genus. Three distinct clades were resolved, corresponding to major geographical subdivisions: an eastern clade that possibly diverged first, then a southern and a western clades which appeared later. We suggest two possible hypotheses concerning the dispersal of the genus across Africa, considering also the patterns of karyotypic variation. Finally, we discuss the taxonomic status of G. gambianus and the relationships between Gerbillurus and Gerbilliscus, as previous studies have suggested that the former should be included in the latter. Our data seem to support the synonymy of the two taxa and suggest that Gerbillurus and Gerbilliscus lineages diverged from a common ancestor appeared in eastern Africa.

The widely used Pavlovian fear-conditioning paradigms used for studying the neurobiology of learning and memory have mainly used auditory cues as conditioned stimuli (CS). The present work assessed the neural network involved in olfactory fear conditioning, using olfactory bulb stimulation-induced field potential signal (EFP) as a marker of plasticity in the olfactory pathway. Training consisted of a single training session including six pairings of an odor CS with a mild foot-shock unconditioned stimulus (US). Twenty-four hours later, the animals were tested for retention of the CS as assessed by the amount of freezing exhibited in the presence of the learned odor. Behavioral data showed that trained animals exhibited a significantly higher level of freezing in response to the CS than control animals. In the same animals, EFPs were recorded in parallel in the anterior piriform cortex (aPC), posterior piriform cortex (pPC), cortical nucleus of the amygdala (CoA), and basolateral nucleus of the amygdala (BLA) following electrical stimulation of the olfactory bulb. Specifically, EFPs recorded before (baseline) and after (during the retention test) training revealed that trained animals exhibited a lasting increase (present before and during presentation of the CS) in EFP amplitude in CoA, which is the first amygdaloid target of olfactory information. In addition, a transient increase was observed in pPC and BLA during presentation of the CS. These data indicate that the olfactory and auditory fear-conditioning neural networks have both similarities and differences, and suggest that the fear-related behaviors in each sensory system may have at least some distinct characteristics.

The African pygmy mice, subgenus Nannomys, constitute the most speciose lineage of the genus Mus with 19 recognized species. Although morphologically very similar, they exhibit considerable chromosomal diversity which is here confirmed and extended by the G-banding analysis of 65 mice from West and South Africa. On the basis of their karyotype and distribution area, the specimens were assigned to at least five species. Extensive differentiation both within and between species was observed that involved almost exclusively Robertsonian translocations, 23 of which are newly described. Two of the rearrangements were sex chromosome-autosome translocations, associated in some cases with partial deletions of the X or Y chromosomes. Several authors have predicted that the highly deleterious effect of this rearrangement would be reduced if the sex and autosomal segments were insulated by a block of centromeric heterochromatin. The C-banding analyses performed showed that among the species carrying X-autosome translocations, one followed the expected pattern, while the other did not. In this case, functional isolation of the sex and autosome compartments must involve other repetitive sequences or genomic traits that require further molecular characterization. Such studies will provide insight into the causes and consequences of the high diversity of sex chromosome rearrangements in this subgenus.

Complete cytochrome b gene sequences allows, for the first time, establishing a nearly complete phylogeny among the Praomys group sensu lato. The genera Praomys, Mastomys and Stenocephalemys appear paraphyletic. Myomys is polyphyletic and this genus name probably needs to be restricted to its type species, M. verreauxii. The genera Zelotomys and Colomys appear as sister groups. Mastomys pernanus and Malacomys verschureni nest within the Praomys group, but their generic assignation must be further clarified. The genus Heimyscus appears closest to Praomys than to Hylomyscus. The different lineages probably result from an adaptive radiation at the end of the Miocene.

Systematics of the genus Arvicanthis, the African unstriped grass rat, are somewhat controversial. Most recent taxonomic revisions list five to six species but the definition of some of these (Arvicanthis dembeensis, Arvicanthis nairobae, and Arvicanthis niloticus) is uncertain. The complete mitochondrial cytochrome b gene (1140 bp) was sequenced for 20 specimens from throughout the range of the genus to determine the intrageneric genetic structure, construct a molecular phylogeny, and evaluate classical taxonomies. Neighbor-joining and maximum parsimony analyses yielded identical phylogenetic trees that identify two major lineages: the first one (1) is composed of specimens usually referred to A. niloticus but representing several distinct species, and the other (2) is a complex including "true" A. niloticus from Egypt and northern West Africa as well as Arvicanthis abyssinicus, Arvicanthis dembeensis, and Arvicanthis somalicus. An analysis on a 357-bp fragment of the cytochrome b including published data on A. nairobae indicates that this taxon is part of clade (1). Calibration of the number of 3rd position transversion changes with the murid fossil record suggests that clades (1) and (2) diverged approximately 5 Myr ago. Arvicanthis niloticus as currently recognized is a paraphyletic association and this name should be restricted to the Egyptian and northern West African sample. We also suggest referring to A. dembeensis as A. niloticus, as our cytochrome b data do not support its recognition as a distinct species. Clade (1) is subdivided in three lineages, geographically corresponding to southern West, Central, and East Africa. The high genetic divergence detected between the Central African lineage and the other two lineages suggests that they probably represent separate species. Clade (2) experienced rapid cladogenetic events during the late Pliocene, with the A. somalicus lineage being the first to emerge, followed by the ancestor of A. abyssinicus and A. blicki. This period was characterized by significant climatic and environmental changes, such as the extension of open habitats, which might have provided a stimulus for speciation in this savanna-dwelling genus. Confrontation of our molecular results with chromosomal data shows a high degree of congruence between the two datasets.

Using 'jet lag' paradigms involving phase shifts in the light-dark (LD) cycle, we studied the effects of S-20098 on the circadian clock of a diurnal rodent. Arvicanthis mordax, entrained to a regular LD cycle, were subjected to advance shifts (i.e. 4, 6 or 8 h) in the LD cycle and injected with vehicle or the melatonin agonist S-20098 (20 mg/kg) the day of the shift (and also on subsequent days in the 6 h or 8 h shift paradigms). In each condition, S-20098 accelerated by about 30% resynchronization to the new LD cycle. These data, which are the first to demonstrate the chronobiotic effects of a melatonin agonist in a diurnal rodent, provide new insights for the design of human chronopharmacological protocols.

A chromosome banding study (R- and C-bands) of a male Taterillus arenarius (Rodentia, Gerbillinae) specimen from Mauritania revealed the presence of an XX/XY1Y2 sex-chromosome system in the karyotype, as found previously in three other congeneric species. This finding allowed us to resolve the phylogenetic affinities of this species within the genus and to propose an evolutionary scenario leading to the formation of the species with an XX/XY1Y2 sex-chromosome system. A review of chromosome data in Taterillus suggests that there may be more species in the genus than hitherto recognized.

Some subspecies of Gazella gazella are studied by means of protein electrophoresis (gazella, cora, and erlangeri) and cytogenetics (gazella, cora, erlangeri and farasani), and are compared to G. subgutturosa. Variability parameters and genetic distances are computed from allozyme data at 24 loci. Percentages of polymorphic loci range between 0 and 20.8%, mean numbers of alleles per locus between 1 and 1.25 and mean heterozygosities between 0 and 0.088. Inside G. gazella genetic distances range between 0.011 and 0.074 (Rogers' distance) and between 0.017 and 0.075 (Nei's distance). Genetic distances between subspecies of G. gazella and G. subgutturosa are around 0.16. C, GTG, and RBG banded karyotypes are given. The results are congruent with the subspecific status of G. g. gazella, G. g. cora, G. g. erlangeri and G. g. farasani, showing no karyological and only slight allozymic differences between them. These results may be important from a conservation point of view, for these populations whose ranges have been significantly declining over the last decades.