Morphology of the middle ear of golden moles (Chrysochloridae)

The middle ear structures of nine species of golden moles (family Chrysochloridae) were examined under the light microscope. Auditory structures of several of these species are described here for the first time in detail, the emphasis being on the ossicular apparatus. Confirming previous observations, some golden moles (e.g. Amblysomus species) have ossicles of a morphology typical of mammals, whereas others ( Chrysospalax , Chrysochloris , Cryptochloris and Eremitalpa species) have enormously hypertrophied mallei. Golden moles differ in the nature and extent of the interbullar connection, the shape of the tympanic membrane and that of the manubrium. The stapes has an unusual orientation, projecting dorsomedially from the incus. It has been proposed that hypertrophied ossicles in golden moles are adapted towards the detection of seismic vibrations. The functional morphology of the middle ear apparatus is reconsidered in this light, and it is proposed that adaptations towards low-frequency airborne hearing might have predisposed golden moles towards the evolution of seismic sensitivity through inertial bone conduction. The morphology of the middle ear apparatus sheds little light on the disputed ordinal position of the Chrysochloridae.     

石灰土和酸性土生境下金花茶组植物叶片钙形态差异

为探究不同生境下金花茶组植物的叶片钙形态特征，该研究以10种石灰土生境和4种酸性土生境的金花茶为对象，测定了其生境土壤的钙含量和pH值，以及该生境下金花茶组植物叶中的硝酸钙和氯化钙、水溶性有机酸钙、果胶酸钙、磷酸钙和碳酸钙、草酸钙、硅酸钙和总钙的含量。结果表明：(1)石灰土生境的土壤钙含量和土壤pH均极显著(P<0.01)高于酸性土。(2)在石灰土生境中，金花茶组植物的叶钙形态以草酸钙(41.17%)为主，而在酸性土生境中则以果胶酸钙(43.10%)为主，除硝酸钙和氯化钙、果胶酸钙外，石灰土金花茶的各叶钙形态和总钙含量均极显著(P<0.01)高于酸性土金花茶。(3)相关性分析结果显示，大部分叶钙形态含量与土壤pH和土壤钙含量呈极显著(P<0.01)正相关，表明土壤环境对金花茶组植物叶钙形态特征具有重要影响。(4)单因素方差分析结果显示，各叶钙形态含量在物种间存在极显著(P<0.01)差异，表明金花茶组植物在物种分化过程中叶钙形态特征具有多样性。(5)基于叶钙形态特征的聚类分析显示，14种金花茶可归为3大类。总体而言，不同生境背景下金花茶组植物的叶钙形态差异可能是...     

Finding a place to live: conspecific attraction affects habitat selection in juvenile green and golden bell frogs

Conspecific attraction plays an important role in habitat selection of several taxa and can affect and determine distribution patterns of populations. The behaviour is largely studied and widespread among birds, but in amphibians, its occurrence seems limited to breeding habitats of adults and gregarious tadpoles. The Australian green and golden bell frogs (Litoria aurea) have suffered considerable shrinking of their original distribution in south-eastern Australia since the 1970s. Currently, with only about 40 populations remaining, the species is considered nationally threatened. In natural conditions, these frogs are aggregated in the landscape and do not seem to occupy all suitable ponds within the occurrence area. To date, studies focusing on the frogs’ habitat have failed in finding a general habitat feature that explains current or past occupancy. This led us to the hypothesis that social cues may play a key role in habitat selection in this species. Using two choice experiments, we tested the preference of juvenile green and golden bell frogs for habitats containing cues of conspecifics of similar size versus habitats without conspecific cues. Tested frogs did not show a preference for habitats containing only scent from conspecifics but did prefer habitats where conspecifics were present. Our results show that conspecific attraction is a determining factor in juvenile green and golden bell frog habitat selection. To our knowledge, this is the first time the behaviour is shown to occur in juvenile frogs in the habitat selection context. From a conservation management point of view, the behaviour may help to explain the failure of reintroductions to areas where the frogs have been extinct, and the non-occupation of suitable created habitats in areas where they still inhabit and develop appropriated management strategies.     

Thyme and isolation for the Sinai baton blue butterfly (<Emphasis Type="Italic">Pseudophilotes sinaicus</Emphasis>)

The distribution of the narrowly endemic butterfly Pseudophilotes sinaicus (Lycaenidae) was studied. Potential habitat within its range was first located and then the quality of that habitat assessed. Degree of shelter, diversity of plant species, and resource area of an individual food plant (Thymus decussatus) all affected habitat quality and together were used to develop an index of habitat suitability applicable to each site. The butterfly's distribution was then studied within the identified network of suitable habitat patches: isolated patches with a small resource area were least likely to contain butterflies. Population size in a patch (as opposed merely to patch occupancy) was affected by resource area and the quality of habitat within that patch. Metapopulation processes and variation in habitat quality therefore appear to combine to describe the distribution of patches occupied by P. sinaicus and their population sizes. This finding provides insights into some of the processes operating on an endemic species throughout its geographical range and has important implications for the conservation of this rare butterfly.     

Character evolution in the orbital region of the Afrotheria

The orbit or eye socket is a highly plastic area of the mammalian skull. There is significant variation within and between the different mammalian orders in the size and position of the bones and foramina that contribute to this region. For this reason, orbital characters are often used in attempts to determine the relationships of the various mammalian groups. This study describes the orbital region of the Afrotheria, the proposed group of endemic African mammals that comprises the paenungulates (elephants, manatees and dugongs, and hyraxes), elephant-shrews, aardvarks, golden moles and tenrecs. Evolution within the Afrotherian orbit is then explored by scoring 19 orbital characters in each Afrotherian genus, and plotting the character state changes on to previously existing phylogenies of the Afrotheria. These phylogenies were all produced from recent molecular work. It was found that there is a great deal of variation in the orbital region within the Afrotheria, most notably in the size of the lacrimal and its contacts with other bones, the appearance of the palatine in the orbit and the structure of the zygomatic arch. Overall, orbital characters strongly supported an elephant-hyrax clade over the more traditional grouping of elephants and sirenians (Tethytheria) within the paenungulates. There was also support for a monophyletic Tenrecoidea (a clade of tenrecs plus golden moles). Additionally, it was shown that there is a great deal of variation in the orbital region among the genera of the Tenrecidae and the Macroscelididae.     

Local ecology and geographic ranges of plants in the Bishop Creek watershed of the eastern Sierra Nevada, California, USA

Aim The physiological requirements and tolerances of a species partially determine both its habitat preferences within a community and its broader geographic range. Therefore, we predicted that local ecology should be correlated with geographic distribution. We tested for a correlation between local ecology and range size, and we attempted to account for this correlation by the climate of the range. Location Bishop Creek Watershed, on the eastern side of the Sierra Nevada, California. Methods We recorded all plant species growing in each of 263 plots in the montane to alpine zones of the watershed. The local habitat preferences of 282 species were described in terms of wetness, elevation, soil, and amount of shade. The size and centre of the geographic range for each species were determined from regional floras. Results Wetness preference within the watershed was significantly correlated with range size. Specifically, plants of wet sites had larger ranges that extend to the north, whereas plants of dry sites tended to have smaller ranges centred to the east. The correlation between local wetness preference and range size was entirely explained by the location of the range centre of the species. Main conclusions A possible reason for the large ranges of mesophilic plants in our study area is that mesic habitats are continuous throughout the western Cordillera, while dry alpine habitats are isolated by valleys to the east. The correspondence between local ecology and geographic distributions implies evolutionary stasis in the niches of these plant species.     

Chromosomal evolution and distribution of telomeric repeats in golden moles (Chrysochloridae, Mammalia)

Golden moles (Chrysochloridae) are small, subterranean mammals endemic to sub-Saharan Africa that together with tenrecs constitute one of six orders in Afrotheria. Here we present a comprehensive karyotypic comparison among six species/subspecies of golden moles based on G-banding and chromosome painting. By expanding the species representation to include a further five species recently published in a companion paper, we were able to map the distribution of telomeric repeats in ten species/subspecies that are representative of six of the nine currently recognized genera. We conclude that: (i) the monophyly of Amblysomus is supported by the amplification of heterochromatin in several pericentric regions and one intrachromosomal rearrangement; (ii) A. hottentotus meesteri groups as sister to a clade that contains A. h. hottentotus, A. h. longiceps, A. h. pondoliae and A. robustus, an association that is underpinned by a shared intrachromosomal rearrangement and the detection of telomeric sequences in the centromeres of all chromosomes of the three A. hottentotus subspecies and A. robustus but, importantly, not in those of A. h. meesteri. These findings indicate an absence of gene flow suggesting that A. h. meesteri should be elevated to specific status. We hypothesize that the lack of gene flow may, in part, reflect hybrid dysgenesis resulting from abnormal meiotic segregation as a consequence of differences in the nature of the centromeric specific satellites; (iii) chromosomes 7 and 13 of Chrysochloris asiatica are fused in both Calcochloris obtusirostris and Eremitalpa granti, but that the position of the centromere in the fused chromosome differs in each species. This suggests that rather than being indicative of common ancestry, the fusion is more likely a convergent character which has arisen independently in each lineage. Furthermore our painting data show two centromeric shifts that are probably autapomorphic for C. obtusirostris. Finally, we conclude that (iv) golden moles are characterized by strong karyotypic conservatism but in marked contrast to the constrained rates of change exhibited by most species, A. robustus is unique in that three autapomorphic fissions define its evolutionary history, and hence the more extensive reshuffling of its genome.     

Bone conduction and seismic sensitivity in golden moles (Chrysochloridae)

Some genera of golden moles are known to possess enormously hypertrophied auditory ossicles. These structures have been implicated as potentially mediating a form of inertial bone conduction, used by the golden mole to detect seismic vibrations. A simple model of ossicular inertial bone conduction, based on an existing model of the human middle ear from the literature, was used in an attempt to examine vibrational sensitivity in these animals. Those golden moles with hypertrophied ossicles are predicted to possess a sensitive inertial bone conduction response at frequencies below a few hundred hertz, whereas species lacking these middle ear adaptations are predicted to have a far less sensitive response in this ecologically important frequency range. An alternative mode of inertial bone conduction in golden moles, potentially conferring sensitivity to vertically-polarized seismic vibrations such as Rayleigh waves, is proposed. Certain behaviours of golden moles described in the literature are interpreted as augmenting seismic sensitivity.     

荒漠草原“土岛”生境群落物种共存机制

经过长期破碎化, 荒漠草原原生硬质灰钙土斑块散布在广大沙化土地中, 形成类似“土岛”的土被结构。为揭示土岛生境的群落物种共存机制, 2016年在宁夏盐池县皖记沟村选取大(200-300 m²)、中(约100 m²)、小(约50 m²)土岛各3个开展调查, 采用Jaccard相异系数、物种生态位宽度和生态位重叠度、零模型、Meta分析, 综合计算和分析土岛内部与外部植物群落相似性、物种生态位宽度和生态位重叠、物种共存格局及其影响因子。研究发现, (1)随着破碎化加剧, 土岛内部植物多样性整体呈现下降趋势, 群落优势种从短花针茅(Stipa breviflora)转变为猪毛蒿(Artemisia scoparia)和短花针茅共优种, 土岛内外群落相似性增加。(2)土岛内外绝大多数物种生态位重叠较小, 生态位重叠在土岛内呈集中分布, 而土岛外则呈均匀发散分布。(3)环境过滤为主的生态过程决定了土岛生境群落物种的共存格局, 随着土岛面积减小, 环境因子对群落物种共存的调控强度降低, 关键性环境因子由土壤细砂粒和黏粒转变为粗砂粒, 显著性竞争物种共存格局在小岛出现。综上所述, 土岛生境对于维持草原物种具有重要作用, 环境过滤主导了荒漠草原物种共存格局。随着生境破碎化加剧或土岛面积减小, 物种共存格局及其调控因子发生转变。保护面积在200 m²以上的大土岛对于恢复荒漠草原区草原成分种和其物种多样性机制都十分必要。     

中条山东段森林乔木树种分布的环境梯度分析与种组划分

利用CCA排序和TWINSPAN分类,探讨了中条山东段森林植被中乔木树种分布与环境梯度的关系,并根据树种在排序图上的相对位置,同时参考相关文献资料,进行了种组划分。结果表明,海拔梯度是影响乔木树种分布的最重要的环境因子,土壤肥力和土壤湿度指数也具有较大的作用。72个树种（含变种）归纳划分为6个种组,即低海拔暖湿型、中低海拔暖燥型、中低海拔温润型、中海拔湿沃型、中高海拔燥瘠型和高海拔冷湿型。每个种组内的树种在生态习性特别是在分布特征上显示出较大的相似性,介绍了各种组分布的生境特征。TWINSPAN分类结果与种组划分吻合较好。     

Functional morphology of the middle ear in Chlorotalpa golden moles (Mammalia, Chrysochloridae): predictions from three models

The ossicular apparatus of golden moles in the genus Chlorotalpa has received comparatively little attention in the literature, although the malleus is known to be intermediate in size between the "unmodified" malleus of Amblysomus and the hypertrophied mallei found in some other golden moles. In the present study, the middle ear structures of three Chlorotalpa species (C. duthieae, C. sclateri, and C. arendsi) are described. Measurements of middle ear structures were applied into three existing models of middle ear function. The predictions from the models suggest that the airborne hearing of Chlorotalpa species is limited to relatively low frequencies, but the impedance transformation by the middle ear apparatus is expected to be reasonably efficient. The sensitivity of the middle ear apparatus to inertial bone conduction is intermediate between that predicted for Amblysomus and that predicted for species with hypertrophied mallei. Hearing in fossorial mammals may be limited by factors other than the middle ear apparatus: the predictions for Chlorotalpa must therefore be treated with caution. However, a consideration of the "intermediate" middle ear morphology of Chlorotalpa species sheds some light on the origin of ossicular hypertrophy in golden moles. The limited enlargement of the malleus seen in Chlorotalpa is expected to have improved seismic sensitivity by bone conduction significantly at low frequencies, while airborne hearing might not have been adversely affected.     

Factors affecting the distribution of the mole (Talpa europaea) in Snowdonia (North Wales)

Moles are widespread in the uplands of Snowdonia, North Wales, and their distribution has been studied in relation to soil physical and chemical characteristics. Moles are significantly associated with freely drained mineral soils of pH greater than about 4.0. They are not present in soils with a very stony matrix which would preclude the construction of an effective tunnel system. Data are presented showing that moles are associated with sites showing a high return of sheep dung and the reason for this may be an increase in arthropod populations associated with decaying dung. The sites sampled which were not selected with this study in mind show that no factors other than soil characteristics need be invoked to explain the present distribution of moles.     

秦岭川金丝猴对高海拔栖息地的某些生理适应

金丝猴是我国特有的灵长类,也是海拔分布最高(4 167m)的灵长类,从生理生态学角度研究金丝猴怎样适应高寒山区的生活,具有重要的科学意义．依据十几年的研究结果,并结合已发表的相关资料,从消化、呼吸、血液、循环、生殖几个方面探讨了金丝猴的指名亚种——川金丝猴对秦岭高海拔栖息地的适应及适应机制     

Molecular support for Afrotheria and the polyphyly of Lipotyphla based on analyses of the growth hormone receptor gene

The order Lipotyphla has generally been viewed as a difficult group to classify. For example, recent morphologically based analyses only weakly support the lipotyphla while molecular evidence renders it polyphyletic, placing the golden moles and tenrecs in the superorder known as Afrotheria. Afrotheria is an hypothesized order that contains elephants, sirenians, hyraxes, aardvarks, elephant shrews, tenrecs, and golden moles. Within this group, it has been suggested that the African lipotyphlans (tenrecs and golden moles) form a monophyletic order sometimes referred to as "Afroscoricida," but more appropriately termed Tenrecoidea. The paper presents a molecular analysis of 36 taxa including representatives of five of the six families in Lipotyphla (Solenodontidae is absent) and all orders within Afrotheria. Parsimony analyses were completed using data from the nucleotide sequence of the tenth exon of the growth hormone receptor gene (GHR). These analyses support both the polyphyly of Lipotyphla and the monophyly of Afrotheria with high bootstrap and jackknife support. In addition, the remaining lipotyphlans (known as Eulipotyphla) appear polyphyletic, as does Tenrecoidea.     

Effects of tree species composition on within‐forest distribution of understorey species

Question: Do tree species, with different litter qualities, affect the within‐forest distribution of forest understorey species on intermediate to base‐rich soils? Since habitat loss and fragmentation have caused ancient forest species to decline, those species are the main focus of this study. Location: Three ancient forests, along a soil gradient from acidification‐sensitive to base‐rich, were studied: Limbrichterbosch and Savelsbos in The Netherlands and Holtkrat in Denmark. Methods: Canopy and soil surveys along transects generated data for Redundancy Analysis on tree – humus relationships. We analysed the distribution of forest plant species with Canonical Correspondence Analysis. The explanatory factors were soil characteristics (pH, organic matter, loam content and thickness of the humus layers), external crown projection, ground water and canopy data. We further analysed the relationship between forest species and humus characteristics with Spearman correlations. Results: Tree species have a significant impact on humus characteristics through the nature of their litter. Humus characteristics significantly explain the distribution of forest understorey species. The pH of the first 25 cm mineral soil and the thickness of the F‐ (fermentation) layer are the primary factors affecting the distribution of ancient forest species. Conclusion: This study indicates that the species composition of the forest canopy affects the distribution of forest understorey species. Ancient forest species are more abundant and frequent underneath trees with base‐rich litter. On acidification‐sensitive soils these relationships were stronger than on more base‐rich, loamy soils.     

Presence and spatio-temporal habitat characterization of Dermatemys mawii (Testudines: Dermatemydidae) in the Grijalva-Usumacinta watershed, Tabasco, Mexico

The Central American River Turtle (Dermatemys mawii) is an endangered species that has been poorly studied. There are no reports on their population status, habitat condition, and the species distribution area is still unknown. This study analyzes the seasonal and spatial variations of their habitat and the presence/absence of D. mawii in three rivers within the Pantanos de Centla Biosphere Reserve (Tabasco, Mexico). For habitat characterization, natural segmentation of rivers was used and three sites per segment were identified, 9 in each rivers (Grijalva and Usumacinta) and 6 in Tabasquillo. Additionally, the evaluation of 11 environmental variables such as water hydrological, physicochemical characteristics and riparian and hydrophytic vegetation were carried out during two different seasons (dry and rainy). The presence/absence of species was assessed with eight fike nets that were set per segment, with a capture effort of 384 hours per trap. The capture per unit effort (CPUE) was used as an indicator of relative abundance. The results indicated spatio-temporal variations in habitat characteristics and the presence of environmental gradients. The principal components analysis (PCA) applied allowed us to determine that the first three components explained 67.8% of the environmental variability. The species presence was confirmed in all rivers, however significant differences exists in their relative abundance: the highest was registered in the Tabasquillo River where the species was present in both seasons and in all segments. Of the 11 environmental variables analyzed, the gradient, shelter and depth were the most indicative of species presence. The obtained results evidenced the importance of riparian vegetation as habitat for Dermatemys. This represents the first approach towards an action plan for a species and its habitat protection within the Pantanos de Centla Biosphere Reserve.     

Habitat selection by the Spiny-tailed lizard (Uromastyx aegyptia): A view from spatial analysis

Many factors affect the habitat selection for animal species, which in turn may greatly affect their distribution in different ecosystems. Understanding the processes that affect habitat selection is also critical for guiding and managing conservation initiatives. Our study aimed to assess the habitat selection by free-ranging Spiny-tailed lizard (Uromastyx aegyptia) by analyzing a geospatial data connecting its burrow parameters to different habitat characteristics within selected sites in Hail region, Saudi Arabia. We examined evidence and patterns of significant spatial clustering for (366) active burrows by linking their parameters (burrow entrance size, burrow entrance width and burrow entrance height), their reference geographical locations and, two habitat characteristics defined by soil type and vegetation cover. The objective of the analysis was to increase the understanding on the burrows aggregation process in the space and, to describe its possible relation to other spatial habitat configurations. Analysis of distances based on the Nearest Neighbor Index (NNI) and hotspots detection in Nearest neighbor hierarchical clustering (Nnh) suggested twelve (12) spatial clusters located within the study area. In addition, a spatial ordinary least square (OLS) and Poisson regression models revealed significant effects of soil type and vegetation cover on burrow parameters (OLS, p < 0.05; Poisson, p < 0.001), which indicate a strong association between burrows parameters and habitats characteristics. Findings from the study also suggest that other factors such as elevations, highways, and human settlement concentration spots could possibly play a major role in defining burrow spatial aggregation and furthermore have a significant impact on habitat selection.     

Habitat Diversity in the Conservation of the Grassland Auchenorrhyncha (Homoptera: Cercopidae,Cicadellidae, Cixidae,Delphacidae) of Northern Britain

Definition of northern British grassland Auchenorrhyncha habitats was carried out using a classification based on analysis of data from 351 sites, involving 121 species, located between Greater Manchester and northern Scotland. Ten habitats were identified showing little influence of geographical position and exhibiting a basic upland-lowland trend. Other factors influencing habitat and species assemblage distribution were soil water, vegetation structure and land cover. An analysis of the species data with satellite-derived land cover data indicated that the lowland covers of tilled land, coast and urban and the upland covers of heath grassland and shrub heath were most important in affecting both species and assemblage distribution. The large-scale survey of grassland sites provided new information on both the ecology and distribution of individual Auchenorrhyncha species. Some were limited to specific habitat types but a considerable number were generalist species found in most or all of the 10 habitat types but showing preferences within upland to lowland or wet to dry site gradients. The ability to generate a subtle grassland Auchenorrhyncha habitat classification with large-scale survey results from standardised and reproducible sampling increases the potential for using habitat diversity for the conservation of grassland Auchenorrhyncha. Habitat preservation would also ensure that species richness (biodiversity) is maintained and that the habitats of rare species are conserved.