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The classification and generic definition in the tropical–subtropical fern family Lindsaeaceae have been uncertain and have so far been based on morphological characters only. We have now studied the evolutionary history of the Lindsaeaceae by simultaneously optimizing 55 morphological characters, two plastid genes (rpoC1 and rps4) and three non‐coding plastid intergenic spacers (trnL‐F, rps4‐trnS and trnH‐psbA). Our data set included all genera associated with Lindsaeaceae, except Xyropteris, and c. 73% of the currently accepted species. The phylogenetic relationships of the lindsaeoid ferns with two enigmatic genera that have recently been included in the Lindsaeaceae, Cystodium and Lonchitis, remain ambiguous. Within the monophyletic lindsaeoids, we found six well‐supported and diagnostic clades that can be recognized as genera: Sphenomeris, Odontosoria, Osmolindsaea, Nesolindsaea, Tapeinidium and Lindsaea. Sphenomeris was shown to be monotypic; most taxa formerly placed in that genus belong to the Odontosoria clade. Ormoloma is embedded within Lindsaea and therefore does not merit recognition as a genus. Tapeinidium is sister to a clade with some species formerly placed in Lindsaea that are morphologically distinct from that genus and are transferred to Osmolindsaea and Nesolindsaea, proposed here as two new genera. We do not maintain the current subgeneric classification of Lindsaea itself, because neither of the two generally accepted subgenera (Lindsaea and Odontoloma) is monophyletic, and most of the sections also appear unnatural. Nesolindsaea shows an ancient biogeographical link between Sri Lanka and the Seychelles and many of the main clades within Lindsaea have geographically disjunct distributions. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 305–359.  相似文献   
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Our understanding of the effects of habitat loss on individual performance is limited due to a lack of experimental studies that take the potential genetic and parental effects producing phenotypic variation into consideration. To assess the relative role of habitat loss on offspring phenotype while controlling for the confounding effects of genetic and parental variation we performed a partial cross‐fostering experiment using the Eurasian Treecreeper Certhia familiaris. The experiment was carried out by swapping half the nestlings in a brood between small and large nesting forest patches to determine the effect of nesting forest patch size on five nestling traits reflecting morphological size, body condition, physiological stress and inflammation status. There was no effect of nesting forest patch size on the offspring traits examined. Instead, we found evidence of genetic and early parental effects on all traits except inflammation status, as well as parental effects after cross‐fostering for all of the measured offspring traits. Our results suggest that genetic and parental effects should be taken into account when making inferences about species’ responses to habitat loss.  相似文献   
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ABSTRACT The isolated gray wolf (Canis lupus) population of the Scandinavian Peninsular is suffering from inbreeding depression. We studied dispersal of 35 wolves fitted with very high frequency (20) or Global Positioning System—global system for mobile (15) radiocollars in the neighboring Finnish wolf population. The growing wolf population in Finland has high numbers of dispersing individuals that could potentially disperse into the Scandinavian population. About half (53%) of the dispersing wolves moved total distances that could have reached the Scandinavian population if they had been straight-line moves, but because of the irregular pattern of movements, we detected no wolves successfully dispersing to the Scandinavian population. Dispersal to the Scandinavian population was also limited by high mortality of wolves in reindeer (Rangifer tarandus) management areas and by dispersal to Bothnian Bay at times of the year when ice was not present. We suggest that when a small wolf population is separated from source populations by distance, barriers, and human exploitation, wildlife managers could promote the population's viability by limiting harvest in the peripheral areas or by introducing wolves from the source population.  相似文献   
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Phylogenetics of Echinodorus (Alismataceae) based on morphological data   总被引:1,自引:1,他引:0  
Echinodorus (Alismataceae) is a genus of aquatic and semi-aquatic herbs naturally distributed from Argentina to the USA but commonly used as ornamentals in aquaria worldwide. The phylogeny of the genus was studied on the basis of 96 morphological characters. The analysis resulted in a single most-parsimonious tree supporting a polyphyletic origin of the genus. However, subgenus Echinodorus together with Echinodorus nymphaeifolius formed a clade. Two large clades can be recognized in Echinodorus s.s. , but previous subdivisions of the genus are not supported and some earlier proposed subspecific combinations were shown to be non-monophyletic. Addition of continuous characters coded as value ranges enhanced both the resolution and the support values of the tree. Hence, inclusion of continuous overlapping data is encouraged in phylogenetic studies.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 291–305.  相似文献   
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Species traits explain recent range shifts of Finnish butterflies   总被引:1,自引:0,他引:1  
This study provides a novel systematic comparative analysis of the species characteristics affecting the range margin shifts in butterflies towards higher latitudes, while taking phylogenetic relatedness among species into account. We related observed changes in the northern range margins of 48 butterfly species in Finland between two time periods (1992–1996 and 2000–2004) to 11 species traits. Species with positive records in at least ten 10 km × 10 km grid squares (in the Finnish National Butterfly Recording Scheme, NAFI) in both periods were included in the study. When corrected for range size change, the 48 butterfly species had shifted their range margins northwards on average by 59.9 km between the study periods, with maximum shifts of over 300 km for three species. This rate of range shifts exceeds all previously reported records worldwide. Our findings may be explained by two factors: the study region is situated in higher latitudes than in most previous studies and it focuses on the period of most prominent warming during the last 10–15 years. Several species traits exhibited a significant univariate relationship with the range margin shift according to generalized estimation equations (GEE) taking into account the phylogenetic relatedness among species. Nonthreatened butterflies had on average expanded their ranges strongly northwards (84.5 km), whereas the distributions of threatened species were stationary (−2.1 km). Hierarchical partitioning (HP) analysis indicated that mobile butterflies living in forest edges and using woody plants as their larval hosts exhibited largest range shifts towards the north. Thus, habitat availability and dispersal capacity of butterfly species are likely to determine whether they will be successful in shifting their ranges in response to the warming climate.  相似文献   
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This paper presents models based on empirical data which can be used to predict the patterns of species richness of vascular plants at the poorly explored mesoscale. Using generalized linear modelling, multiple regression models of species richness in the Kevo Nature Reserve, North Finland, are built with a training set of 257 grid squares and 33 environmental variables. We validated the accuracy of the derived models with an independent test set of 100 grid squares. Two different modelling approaches are used: one where species richness is treated straightforwardly as the response variable, and another where it is tentatively stratified into two groups according to taxon types, i.e. alpine taxa versus wide-spread and silvine (forest) taxa. However, the latter approach only marginally improved the accuracy of the predictions of total number of species. Linear altitudinal variables were among the best predictors of vascular plant richness at the mesoscale. As variables involving altitude are crude surrogates for energy-related factors, the results support the available energy hypothesis and advocate its significance in richness-environment relationships. Other important predictors of species richness included length of rivers and brooks, abundance of cliff walls, occurrences of steep-sided gorges and valleys, and relative abundance of gabbro in bedrock. However, the accuracy of the predictions in the derived models is relatively modest. This points towards the necessity of field work as a final guarantee to identify local hotspots of vascular plant species in a subarctic landscape. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
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