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The study of rich material of Pterophoridae from Siberia and the Russian Far East revealed 96 species to inhabit these regions. 24 of them are reported for the first time from Asian Russia and 11 species and 2 genera (Sibiretta gen. nov. and Septuaginta gen. nov.) are described as new. Furthermore the genus Snellenia gen. nov. is described and isolated from the genus Stenoptilia, and previously unknown females are described for three species.
The morphology of the skeletal portions of the sting apparatus is described and compared in 63 genera of myrmicine ants in order to evaluate its taxonomic potential in this difficult subfamily. The survey covers about half of the myrmicine genera, and an but 3 small tribes (Ochetomyrmecini, Melissotarsini, Stegomyrmicini). Interspecific variation in the apparatus is described in a third of the genera examined. In addition, the sting apparatus of the primitive ponerine ant, Amblyopone pallipes is described for comparison with the primitive myrmicines; and the sting associated glands (poison gland, Dufour's gland) are illustrated for single species of Amblyopone, Basiceros, Monomorium, Aphaenogaster, Crematogasier, and Zacryptocerus.
The growth of blood vessels is crucial for organ growth in the embryo and repair of wounded tissues in the adult. An imbalance in this process contributes to numerous malignant, inflammatory, ischemic, infectious and immune disorders (Ferrara et al., 2003). Postnatal neovascularization occurs through the recruitment of progenitor cells and angiogenesis. Integrins are heterodimeric cell surface molecules and are the main receptors for extracellular matrix proteins. Regulation of integrin activation is crucial during embryonic development and during adult life. Dysregulation of integrin activity leads to severe diseases. In this study, we have demonstrated that Rap1, a small GTPase regulating integrin activity, and its GEF Epac1 are expressed in both EPC and endothelial cells. Moreover, the pharmacological activator of Epac activates the small GTPase Rap1 in progenitor cells. In parallel the angiogenic growth factors VEGF and bFGF activate Rap1 in endothelial cells. In addition, the regulation of Rap1 activity in EPC and in endothelial cells plays an important role in the regulation of migration and adhesion to matrix proteins, by regulating the activity of different integrins, a mechanism known as integrin inside‐out signaling. Furthermore, regulation of Rap1 activity affects probably indirectly through outside‐in signaling of integrins the activity of several and crucial proteins such PKB/Akt and focal adhesion kinase in endothelial cells. In line with these results, we have demonstrated that Rap1 activity affect angiogenesis, homing of EPC to ischemic tissues and thereby postnatal neovascularization. The understanding how Rap1 regulates integrin activity in endothelial cells is still not completely clear, for example we have demonstrated that the known effectors of Rap1 mediating the increase of integrin activity in T and B cells, such as RAPL and RIAM are, respectively, either not increasing integrin activity or not expressed in endothelial cells. We aim to find the effector of Rap1 promoting integrin activity in endothelial cells and how RAPL regulates integrin functions and angiogenesis. Moreover data from us and others using genetic models and generation of Rap1a or Rap1b deficient mice or deficient for Rap1a and Rap1b led to embryonic lethality suggesting that Rap1 is a key node protein during embryonic development. The development of conditionnal Rap1a/b endothelial/pericytes restricted deficient mice will help us to decipher more precisely the role of Rap1 during vascular development and angiogenesis.
The Indian Hill Mynah (Gracula religiosa) was studied in the field in Assam in north-east India. The aims of the study were two-fold: (i) to understand better this bird's exceptional ability in captivity to imitate human speech; and (ii) to provide background understanding to studies of the importance of early auditory experience and of vocal imitation in the development of normal song patterns in birds. First is given a brief description of the distribution, general behaviour, and breeding biology of this arboreal, sexually isomorphic, semi-gregarious species. The remainder of the monograph deals with vocalizations; these were either tape-recorded in the field, or transcribed directly using a written notation developed for the purpose. Any wild adult Mynah of either sex possesses four categories of vocalizations: (i) 'Chip-call'; a loud piercing squeak made in contexts which include alarm. (ii) 'Um-sound'; a soft grunt, acting in close range social contexts, and (like chip-calls) common to all individuals. (iii) 'Whisper-whistles': several soft sounds of types unique to the individual. (iv) 'Calls': several loud noises, of extremely varied patterns. The bulk of the monograph deals with 'calls', as defined thus. Calls were compared quantitatively with one another by a method developed which measured the degree of overlap of one sonogram with a tracing of a second sonogram. Both by this method and by ear, calls were divided into discrete types, without intermediates. Birds of either sex have a repertoire of usually between five and twelve such call types, some of which are produced much more commonly than others. Repertoires tend to be larger in birds which call more frequently, or which have mates with large repertoires. The repertoire of a given bird stays largely constant from year to year in size. composition, and proportions. No bird shares any of its call types with its mate, but it shares several of them with near neighbours of the same sex. There is a progressive change of dialect with distance, such that birds nesting more than about 14 km apart have no call types in common. No general characteristics of call structure could be found which were indicative of the sex of the caller, but in a known locality the call type made immediately reveals the sex of the bird producing it. Call types are learnt by selective imitation of neighbouring individuals during a young bird's first several months. A call type common in the repertoire of one bird tends also to be common in the repertoire of a neighbour, except at the edge of the limited range of that call type. Which particular call type a calling bird selects from among those in its repertoire is discussed. Few call types could be related to non-auditory contexts. A bird is likely to repeat the call type last made, and also tends to standardize the order in which it produces its different call types; this standard order tends to be the same as that of its neighbours. A birdtends also to reply at once and to standardize the call type it makes in immediate reply to a particular call type of its mate; again, neighbouring pairs of birds tend to use the same standardized call and reply types. The length of the interval between a particular call and its reply tends to be constant in a given pair of birds, and approximately the same in neighbouring pairs. These are all further aspects of extensive but selective vocal imitation by Mynahs of adult birds; other species are not imitated. Information on calling when in contact with other pairs came mainly from playback experiments, when single calls were presented to nesting pairs of Mynahs. Response strength was measured by the incidence of flight, number of subsequent vocalizations, latency of response, and proportion of playbacks ignored. When presented with playbacks of calls of familiar types (of neighbours) and of unknown types (of strangers), birds responded more strongly to the familiar than to the unknown call types. They did, however, respond somewhat to the unknown call types, which were of patterns never previously heard by them, presumably recognizing these as being Mynah calls by their sound quality. Mynahs responded as strongly to playbacks of neighbours' calls which were not in their own repertoire as to playbacks of neighbours' calls which were. A bird tends to match at once the call last heard (either from a tape recorder or from a wild neighbour), itself producing the same call type at once, if it possesses it in its own repertoire. That call type, and others associated with it, also occurs more frequently thereafter. Thus calls heard affect calls made, and vice-versa since other individuals nearby behave similarly. A change of nearest neighbours in successive years was shown to affect one pair's repertoire proportions. Further playback experiments showed that Mynahs were able to distinguish between a single call made by their neighbours and a single call of the same call type made by their mates. Small but consistent differences were found in the sonograms of such calls of the same type made by different birds. The structure of a single call type may change gradually with distance. The development of vocalizations with age is briefly described. In the final discussion sections, the ways in which, and the extent to which, Mynahs are able to determine the species, home locality, sex and individual identity of other Mynahs are outlined. There follow consideration, and comparison with other species: (i) of various aspects of repertoires; (ii) of the distribution of call types among different individuals; (iii) of the dynamic aspects of calling, and a scheme is proposed which accounts for the selection for utterance of a particular call type from the repertoire; and (iv) of the organization and coordination of calling. The lack of imitation of other species in the wild is discussed, and contrasted with the several ways in which wild Mynahs imitate one another in various aspects of their calling.
Classical mutagenesis
(1992)
Classical genetic analyses require the presence of at least two different alleles per locus. Until the mid 1920's for the different alleles the investigators had to rely on spontaneous mutations. Since then mutagenic agents (mutagens) became available and these discoveries greatly enhanced the power of genetic analyses. Mutation is defined here as a heritable chemical alteration within the gene or the mutation process bringing about the change. Mutant is the individual (cell) containing the mutation. Point mutations are assumed to be free of loss, gain or rearrangement within the nucleotide sequence. Fonvard mutations are changes from the wild type allele (the allele predominant in wild populations) to a new allele, and the reverse process is backmutation. The frequency o/mutation per locus per generation (mutation rate) must be distinguished from mutant frequency, indicating simply the number of mutants in a population. Mutation in the broad sense involves also hereditary changes in chromosome number (polyploidy and aneuploidy) and chromosome structure, visible through the light microscope. The latter types are frequently called chromosomal aberrations. Arabidopsis, without further qualifications, in this context, will refer to Arabidopsis thaliana (L.) Heynh. in its diploid form (2n = 10). This species has three genomes, the nuclear, plastidic and the mitochondrial. Its nuclear genome (n = 5) is the smallest among higher plants (Leutweiler et al., 1984), containing about 0.7 - 1 x 108 bp, and redundancy is very low (Meyerowitz and Pruitt, 1985). The plastid genome is about the same size as that of the mcYority of higher plants, ca. 150 kb. The size of the mitochondrial genome is ca. 400 kb. Arabidopsis is an excellent tool for genetics and its critical features and known mutants have been reviewed (R&Iei , 1970, 1975a,b; Kranz, 1978; Meyerowitz and Pruitt, 1984; Meyerowitz, 1987, 1989; Estelle and Somerville, 1986; Bowman et al., 1988).
Results from a comparative anatomical study of the mesosomal skeleton of Chalcidoidea are presented. External and internal features are described and illustrated for 39 chalcidoid taxa, representing 16 families and 29 subfamilies. This is the most comprehensive morphological study ever conducted for the superfamily. The mesosoma was dissected, macerated and investigated using scanning electron microscopy. The mesothorax and metathorax contributed most of the phylogenetically relevant information. The metafurca is highly variable within Chalcidoidea but seems to be relatively constant at the subfamily level. One hundred and fifty-four morphological characters were scored and analysed cladistically. Outgroup species were chosen from six apocritan superfamilies: Stephanoidea, Ceraphronoidea, Cynipoidea, Platygastroidea, Proctotrupoidea and Mymarommatoidea. Some previously suggested chalcidoid relationships were retrieved: (1) Pteromalidae: Pteromalinae + Miscogasterinae + Panstenoninae; (2) Perilampidae + Eucharitidae; (3) Chalcididae + Leucospidae + Eurytomidae; (4) Eulophidae: Eulophinae + Tetrastichinae + Entedoninae; and (5) Eupelmidae + Encyrtidae, Mymarommatoidea renders Chalcidoidea paraphyletic in our analyses; however, the taxon sample is too restricted to provide a robust hypothesis. Three previously unreported putative autapomorphies of Chalcidoidea were revealed: (1) presence of an exposed, triangular or diamond-shaped prosternum; (2) presence of a percurrent mesopleural sulcus anteriorly terminating in the acropleuron; and (3) presence of paired metapectal plates lateral to the metafurca.
Lepidoptera phylogeny and systematics : the state of inventorying moth and butterfly diversity
(2007)
The currently recognized robust support for the monophyly of the Lepidoptera (and the superorder Amphiesmenoptera comprising Lepidoptera + Trichoptera) is outlined, and the phylogeny of the principal lineages within the order is reviewed succinctly. The state of the taxonomic inventory of Lepidoptera is discussed separately for ‘micro-moths’, ‘macro-moths’ and butterflies, three assemblages on which work has followed historically somewhat different paths. While currently there are about 160,000 described species of Lepidoptera, the total number of extant species is estimated to be around half a million. On average, just over one thousand new species of Lepidoptera have been described annually in recent years. Allowing for the new synonyms simultaneously established, the net increase in species numbers still exceeds 800/year. Most of the additions are foreseeable in the micro-moth grade, but even for butterflies ca 100 species are added annually. Examples of particularly interesting new high-rank taxa that have been described (or whose significance has become realized) since the middle of the 20th century include the non-glossatan lineages represented by Agathiphaga and Heterobathmia and the heteroneuran families Andesianidae, Palaephatidae, Hedylidae and Micronoctuidae. Some thoughts on how present and future systematic lepidopterology might be prioritised are presented.