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1.
Gender exponence in underived French nouns is particularly opaque. In this paper, we identify two subsystems of gender assignment: monogendered nouns, bi-gendered nouns; we show what they share and where they diverge. We show how the notorious floating final consonants of the language are handled in each subsystem for purposes of gender exponence. Our analysis and proposals develop in two steps: (a) we elaborate on the internal structure of √P, arguing that it is more richly articulated than had been assumed in previous work; (b) we propose that a gender feature sitting on n probes into its complement √P for valuation. Our proposal opens a range of selectional options of √P by n. These selectional options along with the probing device they feed, are shown to account for the French evidence.  相似文献   

2.
3.
Parallel evolution in phenotype may result when closely related taxa are adapting in the face of similar ecological pressures. Here, we discuss possible parallelism in shell morphology in the context of the microgeographic phylogeography of two conchologically distinct sympatric hydrocenid snails inhabiting a limestone outcrop and its cave system, Georissa pyrrhoderma and Georissa silaburensis, respectively, at Mount Silabur in Sarawak, Malaysian Borneo. Our results show a certain degree of morphological parallelism of a third, possibly new, cryptic Georissa species within the same cave that strongly diverged from its above-ground sister species, G. pyrrhoderma. We found that both sympatric cave species have shifted from a more sculptured, conical shell toward a broader, less sculptured form.  相似文献   

4.
Populations of forms intermediate between Carabus (Ohomopterus) insulicola and Carabus (Ohomopterus) arrowianus occur at the boundaries between the two species in the Kiso Valley, Nagano Prefecture, central Honshu, Japan. Morphological and mitochondrial DNA analyses revealed that these populations are derived from a hybrid swarm established as a result of secondary contact between the two species. A similar hybrid swarm has been reported in the Ina Valley, an adjacent river basin separated by the Kiso Mountain Range, where the two species are distributed parapatrically. The hybrid swarm individuals in the two valleys show parallelism in the morphological evolution of the male genitalia upon secondary contact and subsequent formation of hybrid swarms between the two Carabus species.  相似文献   

5.
Abstract

Lembotropis emeriflorus (Rchb.) Skali?ka in the Carnian Alps too.—Lembotropis (=Cytisus) emeriflorus, endemic species between the lakes of Lugano and Como, occurs also in the Southern Carnian Alps, where it grows either on gravelly habitats or on rocky slopes or under Austrian pine woods of the mountain zone. After this discovery its distributional pattern is now a typical bicentric one.  相似文献   

6.
The genus Bicyclus is one of the largest groups of African butterflies, but due to the generally cryptic nature and seasonal variation of adult wing patterns, there has been a lot of systematic confusion. With a large research community working with the model species Bicyclus anynana there has been increasing interest in the evolutionary history of the genus. A previous phylogeny started to unravel interesting patterns, but only included 61% of the then known species. With a range of new species having been described in the last decade there has been a need for an updated phylogeny for the genus. We present the most complete phylogeny of Bicyclus yet, including 93% of the currently 103 recognized species and make a range of taxonomic revisions. We revise the status of four previous subspecies and synonymized taxa that in the light of the new genetic data are raised to species level. We also subsume two subspecies and describe a new species, Bicyclus collinsi sp. nov., based on both genetic and morphological evidence. A further new taxon is identified, but not described at this point due to lack of morphological data. Our phylogeny lays a solid foundation for better understanding the evolution of Bicyclus and highlights key species-groups and complexes with intriguing ecological patterns making them prime candidates for future studies.

http://zoobank.org/urn:lsid:zoobank.org:pub:2F775351-097E-4CD7-8F8F-A90B26D52DE8  相似文献   

7.
A robust phylogeny estimate for the family Furnariidae (sensu lato) was obtained using sequences of two nuclear introns and one mitochondrial gene (cyt b). Contrary to the widely accepted sister-group relationship of ovenbirds (Furnariinae) and woodcreepers (Dendrocolaptinae), a basal clade is suggested for Sclerurus and Geositta, while Xenops, hitherto considered an aberrant ovenbird, was found to occupy a basal position on the woodcreeper lineage. The morphological variation is re-interpreted in view of this revised phylogenetic hypothesis. Presumably, the remarkable adaptive radiation in this family started as primitive, Sclerurus-likes forms, which used the tail as a prop during terrestrial feeding, lured up to seek food on tree-trunks. The two basal woodcreeper genera, Xenops and then Glyphorynchus, show strong cranial specializations for hammering in wood, thus presenting a remarkable parallelism with the family Picidae, Xenops resembling a piculet, Glyphorynchus, a diminutive woodpecker. However, this specialization was lost in other woodcreepers, which show a more normal passerine skull, adapted for probing and prying in tree-trunk crevices and sallying for escaping insects. The ovenbirds developed a more flexible (rhynchokinetic) bill, well suited for probing and retrieving hidden prey in dead-leaf clusters and debris suspended in the vegetation, and in epiphyte masses. Adaptations to live in open terrain are secondary.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10336-004-0054-5Communicated by A.J. Helbig  相似文献   

8.
The article aims to analyze Ancient Greek complex verbs in -é?? from a constructionist perspective. These verbs are usually accounted for as the effect of a conversion from adjectival and/or nominal compounds in -os (and, eventually, -on). However, this account does not explain why in complex -é?? verb formations there seem to be two parallel morphological processes which ??feed into?? each other: nominal/adjectival compounds in -os can generate complex -é?? verbs, but also complex -é?? verbs can generate compound nouns or adjectives ending in -os. Moreover, both of these complex formations can give rise to new free simple words (both nouns and verbs) by means of a process of reanalysis. Construction morphology allows us to provide a single picture describing these processes, exploring and explaining all possible interrelations.  相似文献   

9.
The drilling mode of feeding is known from two clades of Gastropoda: Caenogastropoda and Heterobranchia. However, the level of convergence and parallelism or homology among these two lineages is unclear. The morphology of the buccal complex is well studied for drilling caenogastropods, but poorly known for drilling nudibranchs. It is also unclear whether the drilling feeding mechanism is similar between inside gastropods. Accordingly, a comparison between the feeding mechanisms of drilling nudibranchs and caenogastropods can help to understand the evolutional trends inside gastropods. In this study, we redescribe the morphology of the buccal complex of drilling dorid nudibranch Vayssierea cf. elegans, and compare it to that of previous investigations on this species and closely related dorid species. We describe the feeding mechanism of this species based on the obtained morphological and literature data and compare it to the feeding mechanisms described for drilling caenogastropods. The feeding apparatus of Vayssierea cf. elegans corresponds to the general morphology of the dorid buccal complex; that is, it has a similar arrangement of the buccal musculature and pattern of radular morphology. However, there are also adaptations to the drilling feeding mode similar to those found in Caenogastropoda: that is, specialized dissolving glands and lateral teeth with elongated pointed cusps; and even Sacoglossa: the specialized muscle for sucking. The feeding process of Vayssierea cf. elegans includes the same two stages as those described for drilling caenogastropods: (a) the boring stage, which is provided by mechanical and chemical activity, and (b) the swallowing stage.  相似文献   

10.
A role for the Pax‐6 homologue eyeless in adult Drosophila brain development and function is described. eyeless expression is detected in neurons, but not glial cells, of the mushroom bodies, the medullar cortex, the lateral horn, and the pars intercerebralis. Furthermore, severe defects in adult brain structures essential for vision, olfaction, and for the coordination of locomotion are provoked by two newly isolated mutations of Pax‐6/eyeless that result in truncated proteins. Consistent with the morphological lesions, we observe defective walking behavior for these eyeless mutants. The implications of these data for understanding postembryonic brain development and function in Drosophila are discussed. © 2001 John Wiley & Sons, Inc. J Neurobiol 46: 73–88, 2001  相似文献   

11.
The question investigated in this paper is whether long-range, parallel trends in evolution can be sustained in divergent though closely related lines. This study examines fossil and recent pongid dentitions, testing the hypothesis of the existence of certain trends in the pongid dental evolution. These are: reduction of the cingulum in both upper and lower molars; morphological and metrical reduction in third molars; mesial movement of the metaconid; buccal shifting of the hypoconulid; and alteration of the Dryopithecus groove pattern. More broadly the study tests conclusions of a previous study concerning parallelism of trends in the hominoid dentition. The results of reduction of the cingulum, reduction of the third molar, and alteration of the occlusal pattern on the lower molars support the theory that similar, long-term trends can operate in the evolution of divergent, though closely related lines. They also demonstrate that morphological resemblances between two forms are not certain proof of recent divergence.  相似文献   

12.
Rhizocephalan barnacles have been reported to parasitize a wide range of king crab species (Lithodidae). So far all these parasites have been assigned to a single species, Briarosaccus callosus Boschma, 1930, which is assumed to have a global distribution. Here we investigate Briarosaccus specimens from three different king crab hosts from the fjord systems of Southeastern Alaska: Lithodes aequispinus Benedict, 1895, Paralithodes camtschaticus (Tilesius, 1815), and Paralithodes platypus (Brandt, 1850). Using molecular markers and by morphological comparison we show that Briarosaccus specimens from these three commercial exploited king crabs are in fact morphologically distinct from B. callosus, and further represent two separate species which we describe. The two new species, Briarosaccus auratum n. sp. and B. regalis n. sp., are cryptic by morphological means and were identified as distinct species by the use of genetic markers (COI and 16S). They occur sympatrically, yet no overlap in king crab hosts occurs, with B. auratum n. sp. only found on L. aequispinus, and B. regalis n. sp. as parasite of the two Paralithodes hosts. © 2015 The Authors. Zoological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London  相似文献   

13.
Amy Rose Deal 《Morphology》2016,26(3-4):313-339
This paper analyzes two patterns of number marking in the DP in Nez Perce (Sahaptian) within the framework of Distributed Morphology. The first involves under-realization of plural on nouns. Number has classically been understood as a feature inherent to nouns, rather than to adjectives that modify them. In Nez Perce, however, only a small set of nouns show number morphology, whereas number morphology is highly productive on adjectival modifiers. Adjectives in fact may realize the plural more than once per word—an instance of multiple exponence. I show that the puzzle of under-realization for nouns can be solved through conditioned allomorphy, providing new evidence for the presence of gender features on n (Lowenstamm 2007; Kramer 2014). The puzzle of multiple exponence (over-realization) for adjectives can be solved through Local Dislocation (Embick and Noyer 2001) combined with very late insertion of reduplicative content (Haugen 2008, 2011), demonstrating one way the DM architecture may produce multiple exponence without recourse to dedicated mechanisms.  相似文献   

14.
Year-to-year variation in phenotypic gender in the monoecious cucurbit, Apodanthera undulata Gray was investigated. Small plants produce no flowers. Larger plants produce only staminate flowers (“male” plants), while a somewhat greater threshold size is necessary for pistillate flower production (cosexual plants). Approximately 85% of the plants that bloomed did not change gender group between years. Two measures of phenotypic gender were used: prospective femaleness, a measure standardized to the population floral ratio, and morphological femaleness, an unstandardized measure. Femaleness of cosexes between years was positively correlated; r values were somewhat greater when using morphological femaleness values. Plants that opened only staminate flowers one year were likely to open only staminate flowers the next year. Similarly, cosexes were likely to be cosexes again the following year, with similar femaleness values. Beyond the threshold size for pistillate flower production, plant size was not correlated with femaleness. These patterns suggest that all plants are male until they reach a certain size and that plants in their cosexual phase may have an intrinsic femaleness tendency due to either genotype or microsite effects.  相似文献   

15.
A recent molecular taxonomic study along the Chilean coast (18° S–53° S) described 18 candidate species of bladed Bangiales of which only two were formally described. Few studies focused on local genetic and morphological diversity of bladed Bangiales and attempted to determine their intertidal distribution in contrasting habitats, and none were performed in Chile. To delimit intertidal distributions of genetic species, 66 samples of bladed Bangiales were collected at Maitencillo (32° S) in four zones: a rocky platform, a rocky wall, and two boulders zones surrounded by sandy and rocky bottoms, respectively. These samples were identified based on sequences of the mitochondrial COI and chloroplast rbcL markers. We also collected 87 specimens for morphological characterization of the most common species, rapidly assessing their putative species identity using newly developed species‐diagnostic (PCR‐RFLP) markers. Eight microscopic and two macroscopic morphological traits were measured. We described and named three of four species that predominate in Maitencillo (including Pyropia orbicularis): Pyropia variabilis Zapata, Meynard, Ramírez, Contreras‐Porcia, sp. nov., Porphyra luchea Meynard, Ramírez, Contreras‐Porcia sp. nov., and Porphyra longissima Meynard, Ramírez, Contreras‐Porcia, sp. nov. With the exception of Po. longissima restricted to boulders surrounded by sandy bottom, and a morphotype of Py. variabilis restricted to rocky walls, the other species/morphotypes have overlapping intertidal distributions. Except for Po. longissima, which is clearly differentiated morphologically (longest and thinnest blades), we conclude that morphology is not sufficient to differentiate bladed Bangiales. Our findings underscore the importance of refining our knowledge of intrinsic and environmental determinants on the distribution of bladed Bangiales.  相似文献   

16.
Background: Phenotypic variations have been observed in populations of west Cuban Pinguicula species. Such populations occur in patches under different ecological conditions associated with specialised habitats and separated by geographical and ecological barriers, which can lead to morphological differentiation.

Aims: To analyse morphological diversity among species and populations of Cuban Pinguicula; and to test if morphological variability is associated with geographical distribution and distance between populations.

Methods: We sampled a total of eight populations of P. albida, P. cubensis and P. filifolia and tested for morphometric differences among them by Principal Component Analysis (PCA) and analysis of variance (ANOVA) based on 31 quantitative traits. We also assessed the geographical isolation with respect to morphological distance.

Results: The studied species showed high morphological variability at both species and population level. Reproductive characteristics appeared to be more promissory than vegetative ones in distinguishing geographical groups since they clearly defined populations; nevertheless a strong component of individual variation was observed. According to the distance analysis, such morphological variations were correlated with fragmented populations and isolation and allowed the differentiation of two morphotypes of P. albida and two of P. filifolia.

Conclusions: We conclude that high phenotypic variation of the analysed species is related to geographical and ecological isolation which have led to the differentiation of morphotypes within species.  相似文献   


17.
Objective: To examine the prevalence and correlates of night eating, the core behavioral symptom of night eating syndrome among adolescents and adults, using two public access survey databases of nationally representative samples. Research Methods and Procedures: Data were extracted for individuals age 13 years or older who completed food diary data for the National Health and Nutrition Examination Survey III (N = 18, 407) or the Continuing Survey of Food Intakes by Individuals (N = 10, 741). Prevalence estimates were calculated for three commonly used definitions of night eating. Logistic regression was used to examine correlates of night eating: type of day, season, gender, age, race/ethnicity, and BMI or obesity. Results: With few exceptions, findings were similar in the two surveys. Night eating is most common during the weekend; prevalence is greatest among young adults (18 to 30 years of age) and least common among individuals age 65 years or older; and is not associated with BMI or obesity. Gender or ethnicity effects were not found to be stable across surveys. Discussion: Experts need to consider type of day, age group, and possibly gender and race/ethnicity when examining population differences in night eating. Longitudinal studies are needed to further examine the link between night eating and obesity.  相似文献   

18.
Understanding the emergence of species through the process of ecological speciation is a central question in evolutionary biology which also has implications for conservation and management. Lake trout (Salvelinus namaycush) is renowned for the occurrence of different ecotypes linked to resource and habitat use throughout North America. We aimed to unravel the fine genetic structure of the four lake trout ecotypes in Lake Superior. A total of 486 individuals from four sites were genotyped at 6822 filtered SNPs using RADseq technology. Our results revealed different extent of morphological and genetic differentiation within the different sites. Overall, genetic differentiation was weak but significant and was on average three times higher between sites (mean FST = 0.016) than between ecotypes within sites (mean FST = 0.005) indicating higher level of gene flow or a more recent shared ancestor between ecotypes within each site than between populations of the same ecotype. Evidence of divergent selection was also found between ecotypes and/or in association with morphological variation. Outlier loci found in genes related to lipid metabolism and visual acuity were of particular interest in this context of ecotypic divergence. However, we did not find clear indication of parallelism at the genomic level, despite the presence of phenotypic parallelism among some ecotypes from different sampling sites. Overall, the occurrence of different levels of both genomic and phenotypic differentiation between ecotypes within each site with several differentiated loci linked to relevant biological functions supports the presence of a continuum of divergence in lake trout.  相似文献   

19.
The marmosets, tribe Callitrichini, are the most speciose clade in the subfamily Callitrichinae, containing 21 species. However, there is no consensus among molecular and morphological systematists as to how many genera should be recognized for the group. To test the morphological support for the alternative generic classifications, this study presents a comprehensive phylogenetic analysis. It is the first such analysis to include all 21 species and employ continuous and discrete osteological, pelage and tegument, karyological and vocal characters. This dataset was combined with nucleotide sequences from two mitochondrial and four nuclear regions. Separate analyses showed that, among morphological datasets, osteological characters were best at solving relationships at more inclusive levels, whilst pelage characters were most informative at the interspecific level. This suggests the presence of different transformation rates for the two character sets. When a single most parsimonious tree was obtained using the 83‐character matrix, three main clades were identified, supporting the division of the marmosets into three genera: Callithrix, Cebuella and Mico. The total evidence analysis that included an additional 3481 molecular characters corroborated most of the morphology‐based clades and also supported a three‐genus classification of the marmosets. This is the first morphological study to support an Amazonian marmoset clade (Cebuella Mico), which is also strongly supported in exclusively molecular phylogenies, and to synonimize Callibella under Mico.  相似文献   

20.
Elodea nuttallii (Planch). H. St John is an introduced aquatic macrophyte which was first observed in France in the early 1950s. The impact of two frequencies of harvesting on the biomass and regrowth strategy of this invasive species was evaluated by assessment of morphological traits monthly from February to October 2003. The effect of this management on the floristic biodiversity was also analysed. Harvesting caused a drastic reduction of biomass of E. nuttallii. Two harvests caused almost total disappearance of E. nuttallii. Furthermore, no significant difference was observed in the architecture of E. nuttallii between an unharvested site and harvested site. In one year, harvest did not allow the development of native aquatic plants.  相似文献   

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