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Over a century after the first description of a polymorphism controlled by a supergene, these genetic architectures still puzzle biologists. Supergenes are groups of tightly linked loci facilitating the co-segregation of combinations of alleles underlying alternative, complex adaptive strategies. The suppression of recombination at supergenes is generally caused by polymorphic chromosomal rearrangements, such as inversions. The existence of inversion polymorphisms and supergene raises theoretical and empirical questions. Why do these architectures evolve? How can alternative combinations of alleles be formed? How and why is polymorphism maintained? The purpose of this paper is to provide answers to these questions by reviewing recent advances in the study of Heliconius numata, an Amazonian butterfly displaying a striking diversity of wing color patterns. In a broad context, this review highlightsmechanisms that play an important role in the evolution of new genomic architecture and in the adaptation of species. [ABSTRACT FROM AUTHOR]

Most bacterial ribonucleases (RNases) known to date have been identified in either Escherichia coli or Bacillus subtilis. These two organisms lie on opposite poles of the phylogenetic spectrum, separated by 1-3 billion years of evolution. As a result, the RNA maturation and degradation machineries of these two organisms have little overlap, with each having a distinct set of RNases in addition to a core set of enzymes that is highly conserved across the bacterial spectrum. In this paper, we describe what the functions performed by major RNases in these two bacteria, and how the evolutionary space between them can be described by two opposing gradients of enzymes that fade out and fade in, respectively, as one walks across the phylogenetic tree from E. coli to B. subtilis. [ABSTRACT FROM AUTHOR]

For decades, human activities have gradually destroyed the natural habitats of wild grapevine, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi, and nowadays this species is endangered in southern Europe. In this paper, 94 populations of this species have been localized and characterized in the Andalusian region in the Iberian Peninsula between 1989 and 2013. Location, ecological aspects, and sanitary characteristics are described. Must properties and in vitro tolerance to calcareous conditions were also checked. The paper also contains a global description of female and male individuals. Two hundred individuals from six river basin populations have been sampled, and their genetic structure analyzed by using 25 nuclear microsatellites loci to investigate the gene diversity of wild grape populations in Andalusia at two levels: total individuals and at river basin populations. Also, the genetic relationship of wild and cultivated accessions has been tested. Wild grapevine is considered the ancestor of the cultivated varieties and should be preserved as this material could be used to start breeding programs of cultivated varieties and also to restore riverbank forests, which constitute one of the worst preserved ecosystems in the area. [ABSTRACT FROM AUTHOR]

Metastatic progression, which begins with the invasion and migration of tumor cells from a primary tumor, marks a major turning point in the evolution of cancer. Indeed, it eventually leads to the formation of secondary tumors, the metastases, which are very often responsible for the patient's death. Understanding the mechanisms controlling the different steps of this process, as well as those explaining the fundamental phenomenon of organotropism (i.e. the distribution of metastases in distant organs by a non-random and tumor-specific process), is essential to define new innovative therapeutic solutions. In this review paper, we will present how biomechanics is an essential element to this understanding, and will emphasize the importance of this orthogonal and promising angle of study as well as our laboratory's focus on the late stages of dissemination, arrest and extravasation of circulating cancer cells and factors secreted by the primary tumor such as extracellular vesicles. [ABSTRACT FROM AUTHOR]

As part of an ongoing survey of scorpion diversity in Colima, Mexico, the isolated mountain Cerro Grande, part of the Biosphere Reserve Sierra de Manantlán, was investigated. Centruroides possanii sp. nov., the fifth species of the genus from the state, was discovered during fieldwork in the massif and is described in the present paper. Physiographical and climatic features of Cerro Grande may restrict the range of this new species; thus, we hypothesized that it may be a microendemic species that requires priority conservation. The new species is not assigned to any Centruroides species group recognized because some of its morphological features do not fit the current diagnosis of any of these groups, and these different groups are non-monophyletic and consequently ill-diagnosed. The new species is profusely illustrated, particularly the hemispermatophore. A distribution map is presented along with the other two more common species distributed in Colima. Because only indirect data on the potency of its venom is available, the medical importance of this new species described here is yet to be known. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to clarify the taxon surrogacy hypothesis relative to vascular plants and bryophytes. A literature review was conducted to obtain papers that met the following criteria: (i) they examined species richness values; or (ii) they evaluated the species richness within the same study sites, or under the same spatial variation conditions. Twenty-seven papers were accessed. The richness of the two taxa, compared in 32 cases, positively co-varied in about half of the comparisons. The response to the spatial variation in environmental or human-induced factors of the two taxa in terms of species richness was rather variable. Based on current knowledge, the main documented findings regard forest habitats and nival gradients. In forest habitats, co-variation in species richness is likely when similar environments are analysed and seems to be strengthened for boreal forests. Along the nival gradient, a different response in terms of richness of the two taxa suggests that vascular plants cannot be considered good surrogates for bryophytes. [Copyright &y& Elsevier]

Abstract: The set of these two theoretical papers offers an alternative to the hypothesis of a primordial RNA-world. The basic idea of these papers is to consider that the first prebiotic systems could have been networks of catalysed reactions encapsulated by a membrane. In order to test this hypothesis it was attempted to list the main obligatory features of living systems and see whether encapsulated biochemical networks could possibly display these features. The traits of living systems are the following: the ability they have to reproduce; the fact they possess an identity; the fact that biological events should be considered in the context of a history; the fact that living systems are able to evolve by selection of alterations of their structure and self-organization. The aim of these two papers is precisely to show that encapsulated biochemical networks can possess these properties and can be considered good candidates for the first prebiotic systems. In the present paper it is shown that if the proteinoids are not very specific catalysts and if some of the reactions of the network are autocatalytic whereas others are not, the resulting system does not reach a steady-state and tends to duplicate. In the same line, these biochemical networks possess an identity, viz. an information, defined from the probability of occurrence of these nodes. Moreover interaction of two ligands can increase, or decrease, this information. In the first case, the system is defined as emergent, in the second case it is considered integrated. Another property of living systems is that their behaviour is defined in the context of a time-arrow. For instance, they are able to sense whether the intensity of a signal is reached after an increase, or a decrease. This property can be mimicked by a simple physico-chemical system made up of the diffusion of a ligand followed by its chemical transformation catalysed by a proteinoid displaying inhibition by excess substrate. Under these conditions the system reacts differently depending on whether the same ligand concentration is reached after an increase or a decrease. [Copyright &y& Elsevier]

Abstract: In this paper, a new algorithm is presented, which makes possible multilevel comparison of BLOSUM protein substitution matrices based on data from different groups of organisms. As an example, a comparison between substitution matrices based on data from two groups of bacterial genomes with different GC content is presented. Our approach includes evaluating the number of amino acid pairs in BLOCKS databases created separately for the two groups of bacteria using protein sequences deposited in the COG database. Differences of distributions of amino acid pair counts are tested using the chi-squared based G-test. Different analysis levels make it possible to distinguish different patterns of amino acid substitution. Application of the algorithm reveals statistically significant differences in amino acid substitution patterns between AT-rich and GC-rich groups of bacterial organisms. The differences are particularly visible in the overall substitution pattern, amino acid conservation pattern and in comparison of substitution patterns for single amino acids. The algorithm presented in this paper can be considered a novel method for multi-level comparison of amino acid substitution patterns. The presented approach is not limited to bacterial organisms and BLOSUM substitution matrices. Statistically significant differences between substitution patterns in the two groups of bacterial organisms with respect to amino acid conservation pattern can be the evidence of different rate of evolutionary change between AT-rich and GC-rich bacterial organisms. To cite this article: M. Pacholczyk, M. Kimmel, C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: Automatic comparison of compositionally biased genomes, such as that of the malarial causative agent Plasmodium falciparum (82% adenosine + thymidine), with genomes of average composition, is currently limited. Indeed, popular tools such as BLAST require that amino acid distributions be similar in aligned sequences. However, the P. falciparum genome is so biased that six amino acids account for more than 50% of the protein composition. One reason for the comparison methods failure lies in the compositional difference between the query and the subject proteomes, which is not taken into account in the amino acid substitution matrices. This paper introduces a method to derive substitution matrices, in particular BLOSUM 62, in the frame of the information theory. It allows the construction of non-symmetrical matrices, taking into account the non-symmetric amino acid distributions. The dirAtPf family of matrices allowing the comparison of P. falciparum and A. thaliana is given as an example. This paper further provides an analysis of the obtained matrices in the frame of the information theory, supporting the discrimination advantage they bring. To cite this article: O. Bastien et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: In this paper we present a travelling-wave analysis of a mathematical model describing the growth of a solid tumour in the presence of an immune system response. From a modelling perspective, attention is focused upon the attack of tumour cells by tumour infiltrating cytotoxic lymphocytes (TICLs), in a small multicellular tumour, without necrosis and at some stage prior to (tumour-induced) angiogenesis. As we have shown in previous work, for a particular choice of parameters, the underlying reaction–diffusion–chemotaxis system of partial differential equations is able to simulate the well-documented phenomenon of cancer dormancy by depicting spatially heterogeneous tumour cell distributions that are characterized by a relatively small total number of tumour cells. This behaviour is consistent with several immunomorphological investigations. Moreover, the alteration of certain parameters of the model is enough to induce bifurcations into the system, which in turn result in tumour invasion in the form of a standard travelling wave. The work presented in this paper complements the bifurcation analysis undertaken by Matzavinos et al. [Math. Med. Biol. IMA 21 (2004) 1–34] and establishes the existence of travelling-wave solutions for the system under discussion by promoting the understanding of the geometry of an appropriate phase space. To cite this article: A. Matzavinos, M.A.J. Chaplain, C. R. Biologies 327 (2004). [Copyright &y& Elsevier]

As classically defined by Macdonald in the early 1950s, for the case of diseases with one vector and one host, the Basic Reproduction Number, R0, is defined as the number of secondary infections caused by a single infective of the same type (vector or host) during its infectiousness period in an entirely susceptible population. In the case of a disease which has one vector and one host, it is easy to show that R0 coincides with the threshold for the establishment of an endemic state: if R0>1 <1, the disease can invade (cannot invade) the host population. In this paper we examine various epidemic situations in which there are more than one vector and/or host. We show that in those more complex systems it is not possible to deduce a single R0 but rather a threshold for infection persistence which is a composite of several quantities closely related to the classical expression of R0. Another definition of R0 given by Diekmann, Heesterbeek and Metz, and denoted in this paper RNGO0 is discussed and applied as an alternative to calculate the thresholds for infection establishment. [Copyright &y& Elsevier]

We show in this paper how simple considerations about bio-arrays images lead to a peak segmentation allowing the genes activity analysis. Bio-arrays images have a particular structure and the aim of the paper is to present a mathematical method allowing their automatic processing. The differential geometry approach used here can be also employed for other types of images presenting grey level peaks corresponding to a functional activity or to a chemical concentration. The mathematical method is based on elementary techniques of differential geometry and dynamical systems theory and provides a simple efficient algorithm when the peaks to segment are isolated. [Copyright &y& Elsevier]

Although scorpions have been described from China since the 19th century, it was only in the early 2000s that this fauna has seen a noticeable improvement in terms of the number and diversity of the described taxa. Some regions of China have been extensively prospected, while others remain largely unexplored. The latter is the case for the Province of Xinjiang, in the Extreme West of the country. A few contributions dealing with scorpions from this region are available, but these mainly concern representatives of the family Buthidae. In the present paper, a new species belonging to the genus Scorpiops Peters, of the family Scorpiopidae Kraepelin, is described from the Taxkorgan Natural Reserve. The description is based on one male and one female collected under stones at altitudes of 4500–4600 m. To our knowledge, this is the first species ever described from the Taxkorgan Natural Reserve and may represent an endemic element within the fauna of Xinjiang Province. [ABSTRACT FROM AUTHOR]

Morphological markers as well as two types of molecular markers, inter-sample sequence repeat (ISSR) and start codon targeted (SCoT) are suitable for species identification of the polygonati rhizoma germplasms. In this paper, we adopted these methods for the identification of rhizomes collected from 47 areas in China. Based on their morphological characters, the collected germplasms were classified into two populations, one with alternate leaf arrangement and the other with verticillate leaf arrangement, and they were comprised of five species and fourteen subgroups. Of the five species identified: Polygonatum kingianum , P. cirrhifolium , P. alternicirrhosum , and P. sibiricum belonged to one cluster, and P. cyrtonema belonged to a different cluster. According to the analysis of both ISSR and SCoT markers, all germplasms with greater genetic similarity were classified into one group. Especially, P. sibiricum and P. cirrhifolium , which shared ∼80% similarity, were clustered together, whereas the germplasms identified as P. kingianum with ∼86% similarity formed a separate clade. P. kingianum showed a much greater genetic similarity with P. cyrtonema than with P. sibiricum . The multidimensional scaling analysis further verified the accuracy and reliability of the molecular marker-based results. Thus, both morphological and molecular methods should be combined for the differentiation of germplasms such as those of polygonati rhizoma. [ABSTRACT FROM AUTHOR]

Discocyrtanus canjinjim sp. n., belonging to the family Gonyleptidae Sundevall, 1833 is described based on nineteen specimens, eleven adult males and eight adult females, collected in the Vila Bela da Santíssima Trindade, in the State of Mato Grosso, Brazil. This new species represents an endemic component for the harvestmen fauna of Chiquitano Dry Forests terrestrial eco-region, being the most occidental point of distribution of the genus, notably found in the Cerrado and the Atlantic Forest. The new species is characterized by femur IV swollen with the same length of dorsal scutum, trochanter IV with prodorsal distal apophysis as a stout hook not bifurcated, and a unique form of genitalia in the genus. This paper also includes the first identification key to the species of the genus after its revalidation. [ABSTRACT FROM AUTHOR]

In this paper, we present some thoughts about the recent developments, made possible by technological advances and miniaturisation of connected visual prostheses, linked to the visual system, operating at different level of this one, on the retina as well as in the visual cortex. While these objects represent a great hope for people with impaired vision to recover partial vision, we show how this technology could also act on the functional vision of well sighted persons to improve or increase their visual performance. In addition to the impact on our cognitive and attentional mechanisms, such an operation when it originates outside the natural real visual field (e.g. cybernetics) raises a number of questions about the development and use of such implants or prostheses in the future.

Endocrine disruption is commonly thought to be restricted to a direct endocrine mode of action i.e. the perturbation of the activation of a given type of hormonal receptor by its natural ligand. Consistent with the WHO definition of an endocrine disrupter, a key issue is the “altered function(s) of the endocrine system”. Such altered functions can result from different chemical interactions, beyond agonistic or antagonistic effect at a given receptor. Based on neuroendocrine disruption by polychlorinated biphenyls and bisphenol A, this paper proposes different mechanistic paradigms that can result in adverse health effects. They are a consequence of altered endocrine function(s) secondary to chemical interaction with different steps in the physiological regulatory processes, thus accounting for a possibly indirect endocrine mode of action. [ABSTRACT FROM AUTHOR]

VIP and its receptors (VPACRs) are largely investigated in vertebrate testis, as well as their functions in the control of spermatogenesis and steroidogenesis. By contrast, a few data are available about the presence and role of VIP in the epididymis. The aim of the present paper was to investigate the localization of VIP and its receptors in the epididymis of two vertebrates: Podarcis sicula , a seasonal reproducer, and Rattus rattus , a continuous reproducer. By immunohystochemical investigation, we demonstrated for the first time that VIP and its receptors are widely represented in the epididymis of Podarcis sand Rattus ; in particular in Podarcis , we showed that during the reproductive period, as well as in Rattus , VIP and its receptors are well represented in all the epithelial cells and the connective tissue of the epididymis; by contrast, during the non-reproductive period, VIP and its receptors are represented only in the connective tissue. The possible role of the VIP/VPACR system in the control of reproduction is discussed. [ABSTRACT FROM AUTHOR]

Three plant oils ( Cymbopogon citratus , Cymbopogon martini , and Pelargonium graveolens ) were developed as EC formulations and tested for their physical stabilities. EC formulations (10EC, 20EC and 30EC) of C. citratus , C. martini and P. graveolens had emulsion stability, spontaneity property, heat and cold stability. EC formulated plant oils were screened against the major seed borne fungi of rice such as Curvularia lunata , Fusarium moniliforme , Bipolaris oryzae , and Sarocladium oryzae . The level of inhibition varied among the concentrations of EC formulations. Among the three EC formulations, that of C. citratus oil 30EC recorded 100% inhibition on the mycelial growth of test pathogens. In the blotter paper method, rice seeds treated with a formulation of C. citratus oil 30EC controlled the infection of C. lunata, F. moniliforme, B. oryzae and S. oryzae in rice seed to the tune of 66.0%, 60.4%, 66.0% and 69.1%, respectively. Seed soaking with formulation of C. citratus oil 30EC showed the highest percentage of normal seedlings, the lowest number of abnormal seedling and fresh ungerminated seeds when tested with the roll-towel method. Seed soaking with 30EC formulation of C. citratus oil increased seed germination, shoot length, root length and vigour of rice seedlings when tested with the plastic tray method. Transmission of pathogens from seed to seedling was reduced significantly by the 30EC formulation of C. citratus oil when tested with the plastic pot method. The effect of the storage life of the 30EC formulation of C. citratus oil showed that it had retained their antifungal effect till the end of the incubation period (120 days), and is able to inhibit the mycelial growth of all test pathogens to the 100% level. [ABSTRACT FROM AUTHOR]

Metamorphosis was a key innovation in insect evolution, wherein the individual acquires characteristic adult features and stops molting during postembryonic development. The ancestral metamorphosis mode was hemimetaboly, in which the embryogenesis gives rise to a first instar nymph with the essential adult body structure. The nymphs grow gradually and the final molt to the adult stage completes the formation of functional genitalia and wings. The metamorphosis mode known as holometaboly emerged from hemimetaboly, which is characterized by embryogenesis that produces a larva with a body form that may be substantially different from that of the adult. The larva grows through various stages until molting to the pupal stage, which bridges the gap between the morphologically divergent larva and that of the winged and reproductively competent adult. In the hemimetabolan and holometabolan modes, metamorphosis is regulated by two hormones: the juvenile hormone (JH) and the ecdysone, plus its biologically active derivative, 20-hydroxyecdysone (20E). 20E is a steroid, and its main role is to promote the successive molts, including the metamorphic one, whereas JH is a terpenoid, whose function is to repress metamorphosis [1]. The action of these hormones is underpinned by the mechanisms that transduce the hormonal signal through a pathway of gene activation. The 20E signaling pathway was first described in the 1990s [2] , whereas the most important details of the JH pathway were unveiled recently. Important components of the JH signaling pathway are the JH receptor, which is the basic helix–loop–helix-Per-ARNT-Sim (bHLH-PAS) protein known as methoprene tolerant (Met), to which JH binds, as unveiled by Jindra's group in the 2010 decade. Another important component is Taiman, also a bHLH-PAS protein that plays the role of co-receptor. Finally, the transcription factor Krüppel homolog 1 (Kr-h1) is the main transducer of the antimetamorphic signal of JH [1]. Kr-h1 was discovered in Drosophila melanogaster as a gene with structural similarity to the segmentation gene Krüppel , with which it shares the zinc-finger motifs and amino acid spacers connecting them. The first evidence that connected Kr-h1 and JH was also obtained in D. melanogaster. In this fly, the adult abdominal epidermis derives from larval histoblasts, which start proliferating after puparium formation. The experiments of Ashburner in 1970 showed that administration of JH prior to the prepupal stage prevents the normal differentiation of the abdominal epidermis, and the bristles that should be formed in the adult are shorter or lacking. In 2008, the experiments of Minakuchi and coworkers indicated that Kr-h1 expressed ectopically in the abdominal epidermis during metamorphosis of D. melanogaster also resulted in missing or short bristles, thereby suggesting that Kr-h1 mediates the antimetamorphic action of JH. New experiments of Minakuchi and coworkers carried out in the beetle Tribolium castaneum in 2009 showed that RNAi depletion of Kr-h1 in young larvae caused a precocious larval–pupal transformation, providing clear evidence that Kr-h1 represses metamorphosis and works downstream from Met in the JH signaling pathway. The antimetamorphic action of Kr-h1 was generalized to hemimetabolans in two parallel papers published in 2011 and conducted, respectively, in the cockroach Blattella germanica by Lozano and Belles, and the bugs Pyrrhocoris apterus and Rhodnius prolixus by Konopová and coworkers. In these two studies, RNAi experiments showed that Kr-h1 depletion in nymphs in the penultimate or antepenultimate nymphal stage triggers precocious metamorphosis [1] (Fig. 1 A). E93 is an early gene in the ecdysone signaling cascade that is specifically expressed in late prepupae of D. melanogaster. As shown by the groups of Thummel and Baehrecke in the 1990 decade, the gene encodes for a protein with RHF domains significantly similar to pipsqueak motifs, which was found to be a key player in the degeneration process of the salivary glands during D. melanogaster metamorphosis. However, the action of E93 in metamorphosis is not restricted to the regulation of degeneration processes, given that it also plays morphogenetic roles. In 2012 Mou and coworkers observed that E93 is widely expressed in adult cells of the pupa of D. melanogaster , where it is required for patterning processes. Studying the induction of the Distal-less (Dll) gene within bract cells of the pupal leg using epidermal growth factor (EGF) receptor signaling, Mou and coworkers found that E93 causes Dll to become responsive to EGF receptor signaling, thus indicating that E93 is both necessary and sufficient for determining this switch. These results suggested that E93 controls the responsiveness of many other target genes and that it is generally required for patterning during metamorphosis. Subsequent RNAi experiments reported by Ureña and coworkers in 2014 showed that E93-depleted D. melanogaster larvae are able to pupate but die at the end of the pupal stage. In T. castaneum , E93 depletion by RNAi prevented the pupal–adult transition, resulting in the formation of a supernumerary second pupa. Similar results were obtained in the cockroach B. germanica , where E93 depletion in nymphs prevented the nymphal–adult transition, giving rise to repeated supernumerary nymphal instars (Fig. 1 B). The same year, Belles and Santos showed that the expression of E93 in juvenile nymphs of B. germanica is inhibited by the transcription factor Kr-h1, thus uncovering the essential mechanism by which JH represses metamorphosis, which was named MEKRE93 pathway [3]. The observation that Kr-h1 represses E93 expression led to propose the MEKRE93 pathway as the essential axis regulating insect metamorphosis. Accordingly, in nymph–nymph transitions, JH acts through its receptor Met-Taiman to induce the expression of Kr-h1 , while Kr-h1 represses the expression of E93. In contrast, the decline of JH production in the final juvenile stage interrupts Kr-h1 expression, E93 becomes de-repressed, thus triggering adult morphogenesis (Fig. 2 A) (Belles and Santos, 2014). RNAi experiments in B. germanica by the same authors also revealed that E93 depletion increases Kr-h1 expression, thus indicating that Kr-h1 and E93 are reciprocally repressed. The inhibitory action of Kr-h1 upon E93 expression was corroborated two years later in the holometabolan T. castaneum by Ureña and coworkers, which extended the MEKRE93 pathway framework to holometabolan metamorphosis. The main difference between the hemimetabolan and holometabolan metamorphoses is the regulation and function of the Broad complex (BR-C) zinc-finger transcription factors. In hemimetabolan species, BR-C is mainly involved in promoting the growth of wing primordia. For example, this was shown in B. germanica by Huang and coworkers in 2013, who additionally reported that BR-C expression is induced by JH and Kr-h1 during juvenile stages. One year later, Ureña and coworkers found that BR-C is repressed by E93 in the metamorphic transition. Furthermore, RNAi studies made in 2019 by the group of Mito and Noji in the cricket Gryllus bimaculatus , a hemimetabolan species, confirmed the mentioned interactions, and additionally discovered that BR-C and Kr-h1 are reciprocally activated. In sharp contrast, and as shown mainly by the group of Riddiford in the decade of 1990, BR-C triggers the formation of the pupal stage in holometabolan species, where JH inhibits the expression of BR-C during larval stages and stimulates BR-C expression after pupal commitment (Fig. 2 B). In 2019, Chafino and co-workers showed that E93 is involved in triggering the pupal stage, as it promotes BR-C expression in T. castaneum. The whole data indicates that the MEKRE93 pathway is conserved in the holometabolan species, which added the E93/BR-C interaction loop to the ancestral (hemimetabolan) pathway during the evolutionary transition from hemimetaboly to holometaboly (Fig. 2 C). [ABSTRACT FROM AUTHOR]

The molecular techniques are the standard tool for the study of the taxonomic position and phylogenetic affinities of the lymnaeid genus Radix Montfort, 1810, and the majority of the European representatives of this taxon have been studied in this respect. However, a plethora of nominal species of Radix described from Northern Asia (Siberia and the Russian Far East) are still characterized only morphologically, raising some doubts concerning their validity. In this paper, we present the triple (morphological, molecular, and zoogeographical) evidence that there is at least one endemic species of Radix , Radix dolgini (Gundrizer and Starobogatov, 1979), widely distributed in Siberia and Western Mongolia. Phylogenetically, it is a sister species to the European R . labiata (Rossmaessler, 1835) [= R . peregra auct.], and their common ancestor most probably lived in the Pliocene, nearly 3.25 Myr ago. Our results assume the existence of an extended dispersal barrier for freshwater hydrobionts between Europe and Siberia in the Late Pliocene that may be important for biogeographical explanations. Three other nominal Siberian species of Radix : R . kurejkae (Gundrizer and Starobogatov, 1979), R . gundrizeri (Kruglov and Starobogatov, 1983), and R . ulaganica (Kruglov and Starobogatov, 1983) proved to be the junior synonyms of R . dolgini . [ABSTRACT FROM AUTHOR]

Résumé L’article engage une investigation historique sur l’origine de l’expression « biologie synthétique » dans le but d’en dégager les principales composantes philosophiques. Les résultats de cette analyse sont ensuite utilisés pour étendre l’examen au terme d’« homme synthétique ». On montre ainsi que les deux notions comportent l’affirmation d’une conviction philosophique commune qui peut se résumer de la façon suivante : « la biologie est de la technologie ». L’analyse de cette affirmation permet de distinguer nettement deux notions qui sont généralement confondues dans la littérature transhumaniste : celle d’homme synthétique et celle d’homme nouveau. Les conséquences de cette distinction cruciale sont discutées. In this paper, we propose an historical survey of the expression “synthetic biology” in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of “synthetic man”. It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: “biology is technology”. The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed. [ABSTRACT FROM AUTHOR]

Résumé Cet article porte sur les liens entre éthique et science, au cours de la période 1974–2014, qui est un moment de grandes avancées des sciences de la vie. Dans un premier temps (1974–1994), l’essor d’une bioéthique d’inspiration philosophique, formulée en termes de grands principes , soutient la recherche, et les savants, appelés à se conduire de façon responsable , pensent pouvoir converger vers des solutions irréprochables et consensuelles aux problèmes posés par les progrès de la science. Dans un second temps (1994–2014), cependant, avec l’entrée dans le jeu bioéthique des sciences humaines et sociales, les pratiques normatives observées sur le terrain révèlent que les attitudes dites responsables sont compatibles avec une pluralité de convictions éthiques divergentes . Alors, les politiques rétablissent un ordre, la loi court-circuite la réflexion éthique , et, loin de rester les sages que l’on croyait porteurs des meilleures solutions, les chercheurs sont accusés d’être irresponsables lorsqu’ils manquent d’honnêteté intellectuelle. The paper is about the links between ethics and science, at a time (1974–2014) when the life sciences expanded rapidly. First (1974–1994), the development of a principlist ethics, set out by philosophers, sustained the research, and the scientists, expected to behave responsibly, felt like they could easily converge towards impeccable and consensual solutions to any problem arising from scientific innovations. Later on (1994–2014), however, while yielding ground to social sciences and ground work, bioethics took an empirical turn; then it became clear that behaving responsibly was compatible with a plurality of divergent normative convictions. Ethics crumbled. Local or national policies restored order, so-called bioethical laws short-circuited ethical reflection. And far from being respected as the wise men, apt to recommend the very best solutions to problems raised by new scientific advances, researchers happened to be deemed irresponsible , as some of them were suspected of lacking intellectual integrity. [ABSTRACT FROM AUTHOR]

In this paper, I examine some important metaphysical lessons that are often presented as derived from two new scientific disciplines: synthetic biology and neuroscience. I analyse four of them: the nature of life, the existence of a soul (the mind-body problem), personhood, and free will. Many caveats are in order, and each ‘advance’ or each case should be assessed for itself. I conclude that a main lesson can nevertheless be learned: in conjunction with modern science, neuroscience and synthetic biology allow us to enrich old metaphysical debates, to deepen and even renew them. In particular, it becomes less and less plausible to consider life, mind, person, and agency as non-natural or non-physical entities. [ABSTRACT FROM AUTHOR]

At the Paris Colloquium held forty years ago, and which this paper celebrates, the issue of psychosurgery had not been tackled yet. At that time psychosurgery was tainted by the controversial history of lobotomy and leucotomy. Supporters of psychosurgery at the time of the Colloquium were preparing their fourth International Conference, which was held in Madrid the following year. This represented a key characteristic of the collective, institutional and symbolic action of psychosurgery practitioners. At the end of the seventies, their strategy changed as noted below. Furthermore, we focus on the special importance of the results presented and commented on by psychosurgery supporters, including its conception and classification throughout the rhetoric historically involved (its supposed ventriloquism, its persuasive strength). Based on this view, we suggest a critical reflection encompassing old and new psychosurgery, while questioning the value of new rhetorical devices for the assessment and presentation of psychosurgery results after the surge of Deep Brain Stimulation. [ABSTRACT FROM AUTHOR]

In 1959, Jacques Monod wrote a manuscript entitled Cybernétique enzymatique [Enzymatic cybernetics]. Never published, this unpublished manuscript presents a synthesis of how Monod interpreted enzymatic adaptation just before the publication of the famous papers of the 1960s on the operon. In addition, Monod offers an example of a philosophy of biology immersed in scientific investigation. Monod's philosophical thoughts are classified into two categories, methodological and ontological. On the methodological side, Monod explicitly hints at his preferences regarding the scientific method in general: hypothetical-deductive method, and use of theoretical models. He also makes heuristic proposals regarding molecular biology: the need to analyse the phenomena in question at the level of individual cells, and the dual aspect of all biological explanation, functional and evolutionary. Ontological issues deal with the notions of information and genetic determinism, “cellular memory”, the irrelevance of the notion of “living matter”, and the usefulness of a cybernetic comprehension of molecular biology. [ABSTRACT FROM AUTHOR]

In his famous book Le hasard et la nécessité (1970), Monod claims that natural evolution is based on the interplay between chance and necessity bringing about adaptive evolutionary change. This article addresses a set of related questions about Monod's conception of chance: what does he mean when he uses the term “chance”? Does he invoke one or many different concepts of chance? What are the implications of his conception about the issue of the deterministic or indeterministic nature of the biological world? Is Monod's view of what chance is relevant in contemporary biology? This paper, structured by these four questions, aims at providing a synthetic study of the way Monod conceptualizes chance, particularly highlighting the metaphysical and epistemological implications of his conception and its value in biology today. [ABSTRACT FROM AUTHOR]

Exploiting the annotation of the western clawed frog Silurana tropicalis genome, we identified a new metallothionein (MT) gene, exhibiting all the features to be considered an active gene, but with an atypical coding region, showing only 17 cysteine residues instead of the canonical 20 cysteines of vertebrate metallothioneins and two anomalous cysteine triplets. However, the presence of a gene in the genome does not ensure its effective expression. By using conventional and Real-Time PCR analyses, we demonstrated that this atypical MT is constitutively expressed throughout the life cycle of the African clawed frog Xenopus laevis ; moreover, this gene is highly expressed in the adult liver, the major site of MT expression and synthesis in vertebrates. To our knowledge, the X. laevis MT described in this paper is the first sequence of a vertebrate MT showing only 17 cysteine residues, arranged in two Cys–Cys–Cys motifs. Phylogenetic analyses also demonstrated that the atypical X. laevis MT merges in the anuran clade, but is the most derived sequence among tetrapods MTs. Finally, Tajima's Relative Rate Test suggested a different evolutionary rate between the canonical X. laevis MT and this novel isoform. [ABSTRACT FROM AUTHOR]

In this paper, a delayed predator–prey model with Hassell–Varley-type functional response is investigated. By choosing the delay as a bifurcation parameter and analyzing the locations on the complex plane of the roots of the associated characteristic equation, the existence of a bifurcation parameter point is determined. It is found that a Hopf bifurcation occurs when the parameter τ passes through a series of critical values. The direction and the stability of Hopf bifurcation periodic solutions are determined by using the normal form theory and the center manifold theorem due to Faria and Maglhalaes (1995). In addition, using a global Hopf bifurcation result of Wu (1998) for functional differential equations, we show the global existence of periodic solutions. Some numerical simulations are presented to substantiate the analytical results. Finally, some biological explanations and the main conclusions are included. [ABSTRACT FROM AUTHOR]

The recently erected cestode order Diphyllobothriidea is unique among all tapeworm orders in that its species infect all major groups of tetrapods, including man. In the present paper, the vitellogenesis of representatives of all three currently recognized families of this order was evaluated, based on ultrastructural (transmission electron microscopy) and cytochemical (detection of glycogen) observations. Vitelline follicles of all taxa studied, i.e. Cephalochlamys namaquensis from clawed frogs ( Xenopus ), Duthiersia expansa from monitors ( Varanus ) and Schistocephalus solidus that matures in fish-eating birds, contain vitelline cells at various stages of development and interstitial cells. Developing vitellocytes are characterized by the presence of mitochondria, granular endoplasmic reticulum and Golgi complexes involved in the synthesis of shell globules and formation of shell globule clusters. Mature vitellocytes contain lipids and glycogen in different proportions. The most significant differences among the three diphyllobothriidean families were found in the presence or absence of lamellar bodies. Variations of vitelline clusters morphology and types of lipid droplets are described and discussed in relation to the presumed evolutionary history of diphyllobothriideans, which belong to the most basal cestode groups. [ABSTRACT FROM AUTHOR]

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota . Richness in Basidiomycota , denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota . Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: Sexually dimorphic glands have convergently appeared in animals and are often responsible for the production of pheromones. In the suborder Laniatores of the order Opiliones (Arachnida), glands of such type are widespread, but there is not a single paper on how they are used. Using Scanning Electron Microscopy and a behavioral approach, we describe glandular openings and how these glands are used, in the harvestmen Gryne perlata and Gryne coccinelloides (Cosmetidae). Males of these two species have glandular openings on the metatarsi of legs I and on the metatarsi IV. Males were shown rubbing the glands of the metatarsi I against their other legs, whereas glands on the metatarsi IV are gently touched on the substrate or rubbed either against other legs, or against the substrate. Not all behaviors were seen in both species. [Copyright &y& Elsevier]

Abstract: This paper reports the role of darkling beetles Pimelia laevigata costipennis and Hegeter amaroides (Tenebrionidae) as intermediate hosts of spiruroid nematodes parasites of the black rat and house mouse of El Hierro (Canary Islands). Larvae of spiruroid species were found in the two tenebrionids (18.1% in P. l. costipennis, 7.8% in H. amaroides), Streptopharagus greenbergi being predominant in both (16.1% and 7.1%, respectively), ahead of Mastophorus muris and Gongylonema type larva. The larval stages of S. greenbergi are described for the first time, and adult worms were obtained experimentally from an infected laboratory rat, allowing the identification of the species. Morphometric measurements of experimental adults match those of adults detected in naturally infected rats on the island. Molecular data for S. greenbergi, and the ITS nucleotide sequence of the genus Streptopharagus are also provided for the first time. After the isolation of S. greenbergi DNA and amplification of the ITS region, the ITS1 of this spirocercid was sequenced and deposited in the GenBank database. [Copyright &y& Elsevier]

Abstract: Plant organs grow in coordinated and continuous way. Such growth is of a tensor nature, hence there is an infinite number of different directions of growth rate in each point of the growing organ. Three mutually orthogonal directions of growth can be recognized in which growth achieves extreme values (principal directions of growth [PDGs]). Models based on the growth tensor have already been successfully applied to the root and shoot apex. This paper presents the 2D model of growth applied to the arabidopsis leaf. The model employs the growth tensor method with a non-stationary velocity field. The postulated velocity functions are confirmed by growth measurements with the aid of the replica method. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a 14-year study about the diet of the Sacred ibis in its main introduction area in France and its impact on native bird species, and compares the data to literature from its native area. During an initial period (1993–2004), the diet was essentially composed of invertebrates such as common aquatic insects (correlated with flooding) or Eristalis larvae picked from the mud (a vacant food niche in France), while scraps of meat taken from rubbish dumps were minor. These traditional preys taken from the same ecosystems as in its native area did not result in an exponential increase of the number of breeding Sacred ibises. Invasive Red swamp crayfish recently replaced other foods in its diet with a resulting sharp increase in breeding pair numbers (R 2 =0.48). As in other parts of the world, vertebrates constituted very accidental preys, and no bird species were really threatened by such predation. Conversely, the Sacred ibis can have a positive effect as a predator of invasive crayfish. Adding the species to the DAISIE list of the 100 most invasive alien species in Europe therefore appears debatable. [Copyright &y& Elsevier]

Abstract: The specific identification and systematic of triatomines have been based fundamentally on morphological observations. These organisms are classified into complexes and specific subcomplexes, principally for morphological parameters and geographical disposition. The use of cytogenetic analyzes has been represented as a tool in systematic and taxonomy of triatomines. Thus, the present work, through the analysis of spermiogenesis, aims to characterize this stage of spermatogenesis in triatomines little studied, and especially to compare it among the species Triatoma lenti and T. sherlocki, to assist in the diagnosis of differentiation of these insects. The presence of the heteropyknotic corpuscle is shown as a diagnostic tool to differentiate T. sherlocki and T. lenti, since it is absent in T. lenti. The analysis of the spermiogenesis in T. sherlocki also allowed us to address morphological differences between elongating cells, which were relatively smaller and more filamentous when compared to T lenti. Furthermore, the flagellum was observed in all stages of cell differentiation and elongation. This structure, which helps in the locomotion of the sperm, is hardly observed in cytogenetic analysis, especially throughout spermiogenesis. Thus, although other comparative approaches should be taken, this paper allowed emphasizing the analysis of spermiogenesis as an important cytotaxonomic tool that assists in the differentiation of morphologically related species, such as T. lenti and T. sherlocki. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a prey–predator system with stage structure for predator. The proposed system incorporates cannibalism for predator populations in a competitive environment. The combined fishing effort is considered as control used to harvest the populations. The steady states of the system are determined and the dynamical behavior of the system is discussed. Local stability of the system is analyzed and sufficient conditions are derived for the global stability of the system at the positive equilibrium point. The existence of the Hopf bifurcation phenomenon is examined at the positive equilibrium point of the proposed system. We consider harvesting effort as a control parameter and subsequently, characterize the optimal control parameter in order to formulate the optimal control problem under the dynamic framework towards optimal utilization of the resource. Moreover, the optimal system is solved numerically to investigate the sustainability of the ecosystem using an iterative method with a Runge–Kutta fourth-order scheme. Simulation results show that the optimal control scheme can achieve sustainable ecosystem. Results are analyzed with the help of graphical illustrations. [Copyright &y& Elsevier]

Abstract: Quorum sensing is a decision-making process used by decentralized groups such as colonies of bacteria to trigger a coordinated behavior. The existence of decentralized coordinated behavior has also been suggested in the immune system. In this paper, we explore the possibility for quorum sensing mechanisms in the immune response. Cytokines are good candidates as inducer of quorum sensing effects on migration, proliferation and differentiation of immune cells. The existence of a quorum sensing mechanism should be explored experimentally. It may provide new perspectives into immune responses and could lead to new therapeutic strategies. [Copyright &y& Elsevier]

Abstract: The last two decades have seen numerous debates in the field of the initial settlement of America and noteworthy was the disagreement between physical and molecular anthropologists. Recently, it has been pointed out that this discordance could partly originate from the description methods and classification labels used in craniometry, which did not account fairly for the within-sample and within-group variance. From there, a federative model for the initial peopling of America has been designed which could now explain the biological variability found at both the craniofacial and genetic level. This is a major step in the study of the initial settlement of America, which deserved to be highlighted. The present paper recalls the two conflicting models that prevailed for the last 20years of anthropological studies in America before browsing the newly accepted hypothesis about the origin of the first Amerindians as seen by its authors. Lastly, the article evokes some areas of investigations, which could furnish significant fallouts about the dynamics of the peopling of Americas in the future. [Copyright &y& Elsevier]

Abstract: Why was sexual selection so important to Darwin? And why was it de-emphasized by almost all of Darwin''s followers until the second half of the 20th century? These two questions shed light on the complexity of the scientific tradition named “Darwinism”. Darwin''s interest in sexual selection was almost as old as his discovery of the principle of natural selection. From the beginning, sexual selection was just another “natural means of selection”, although different from standard “natural selection” in its mechanism. But it took Darwin 30 years to fully develop his theory, from the early notebooks to the 1871 book The Descent of Man, and Selection in Relation to Sex. Although there is a remarkable continuity in his basic ideas about sexual selection, he emphasized increasingly the idea that sexual selection could oppose the action of natural selection and be non adaptive. In time, he also gave more weight to mate choice (especially female choice), giving explicit arguments in favor of psychological notions such as “choice” and “aesthetic sense”. But he also argued that there was no strict demarcation line between natural and sexual selection, a major difficulty of the theory from the beginning. Female choice was the main reason why Alfred Russel Wallace, the co-discoverer of the principle of natural selection, engaged in a major controversy with Darwin about sexual selection. Wallace was suspicious about sexual selection in general, trying to minimize it by all sorts of arguments. And he denied entirely the existence of female choice, because he thought that it was both unnecessary and an anthropomorphic notion. This had something to do with his spiritualist convictions, but also with his conception of natural selection as a sufficient principle for the evolutionary explanation of all biological phenomena (except for the origin of mind). This is why Wallace proposed to redefine Darwinism in a way that excluded Darwin''s principle of sexual selection. The main result of the Darwin–Wallace controversy was that most Darwinian biologists avoided the subject of sexual selection until at least the 1950s, Ronald Fisher being a major exception. This controversy still deserves attention from modern evolutionary biologists, because the modern approach inherits from both Darwin and Wallace. The modern approach tends to present sexual selection as a special aspect of the theory of natural selection, although it also recognizes the big difficulties resulting from the inevitable interaction between these two natural processes of selection. And contra Wallace, it considers mate choice as a major process that deserves a proper evolutionary treatment. The paper''s conclusion explains why sexual selection can be taken as a test case for a proper assessment of “Darwinism” as a scientific tradition. Darwin''s and Wallace''s attitudes towards sexual selection reveal two different interpretations of the principle of natural selection: Wallace''s had an environmentalist conception of natural selection, whereas Darwin was primarily sensitive to the element of competition involved in the intimate mechanism of any natural process of selection. Sexual selection, which can lack adaptive significance, reveals this exemplarily. [Copyright &y& Elsevier]

Abstract: As part of a breeding strategy applied to pea (Pisum sativum L.), we propose the use of modelling as a tool for studying flowering time. The pea, both a crop and a model species for developmental processes, represents a valuable tool for systems biology approaches. A preliminary computational model for flowering control was previously developed based on genetic and physiological approaches. This paper discusses possible improvements of the model based on recent molecular advances on the regulation of flowering in peas and the model species Arabidopsis thaliana. A combination of a genetic approach together with agroecophysiological models that are not based on genotype, built into a complete model for flowering time prediction is also proposed. This complete model should allow an accurate prediction of flower initiation and also provide an integrative tool that will be useful for various purposes, from genetic networks to crop models. To cite this article: B. Wenden, C. Rameau, C. R. Biologies 332 (2009). [Copyright &y& Elsevier]

Abstract: The authors investigated in this paper the attractiveness of a water colonized (‘positive’ breeding site) or not (‘negative’ breeding site) by larvae of Aedes aegypti on gravid females and then characterized their physicochemical properties to identify and quantify the principal components. The results showed that the water that sheltered several generations of larvae was more attractive to gravid females than water that had never been colonized. The water in a ‘positive’ breeding site contains 2.5 times more ammonium ions (NH+ 4), four times more nitrite ions (NO− 2) and 20 times more nitrate ions (NO− 3) than ‘negative’ breeding water. The authors suggest that in the ‘positive’ breeding sites, where the larvae absorb the organic matter, the turbidity of water decreases, which makes it possible for organic nitrogen to be converted into nitrites and nitrates via the nitrifying activity of the bacteria (NH+ 4 →NO− 2 →NO− 3). It is likely that chitin, while accumulating and decomposing at the bottom of the breeding site, may increase the percentage of organic carbon and ammonium ions, then reinforcing the nitrification process. Conversely, in the ‘negative’ breeding site where the conditions of evolution of the nitrifying bacteria are more restrictive, the nitrogen remains primarily in its organic form. To cite this article: F. Darriet, V. Corbel, C. R. Biologies 331 (2008). [Copyright &y& Elsevier]

Abstract: With the advent of molecular biotechnologies, new opportunities are available for plant physiologists to study the relationships between wheat traits and their genetic control. The functional determinations of all genes that participate in drought adaptation or tolerance reactions are expected to provide an integrated understanding of the biochemical and physiological basis of stress responses in wheat. However, despite all the recent technological breakthroughs, the overall contribution of genomics-assisted breeding to the release of drought-resilient wheat cultivars has so far been marginal. This paper critically analyses how biotechnological, genetic and information tools can contribute to accelerating the release of improved, drought-tolerant wheat cultivars. Armed with such information from established models, it will be possible to elucidate the physiological basis of drought tolerance and to select genotypes with an improved yield under water-limited conditions. To cite this article: C.-X. Zhao et al., C. R. Biologies 331 (2008). [Copyright &y& Elsevier]

Abstract: A key point in the study of acoustic perception is whether brain responsiveness to sounds depends on sound acoustic structure or sound perceptive salience. Songbirds provide some evidence that higher auditory regions are sensitive to the subjective importance of the stimulus for the subject. In the present paper, we compare brain activation elicited by mate versus non-mate calls in female zebra finches Taeniopygia guttata. Using playback, we examined the responsiveness of the caudal telencephalon by measuring the evoked expression of the immediate early gene ZENK. Our results show that mate calls elicit a significantly higher ZENK expression than the calls of another male in hippocampus, but not in auditory areas. Using a hierarchical ascending classification, we show that this difference in brain activation is not explained by call acoustic structure, but relies on call identity. Thus, these results give evidence for a genomic response to calls in hippocampus that differentiate between call identity, and not between call structure. Our study gives further insight into the implication of the hippocampus in sound recognition in female songbirds. To cite this article: C. Vignal et al., C. R. Biologies 331 (2008). [Copyright &y& Elsevier]