Ecological Characters Research Articles

Word as Object: A View of Language at Hand

Here we develop a view of language as a form of material engagement, one that foregrounds its embodied and ecological character. Achieving such a view, however, requires disabusing ourselves of certain received and deeply entrenched notions. We present a thought experiment meant to illuminate the materiality of language, as a technological activity on par with the construction and manipulation of artifacts. We explore its implications, justifying the comparison with actual languages while emphasizing revealing differences. Ultimately, we hope to expose the embodied and enactive nature of language, offering a view of language as continuous with our engagement with the environment, as opposed to a picture of language as an essentially symbolic system or code.

Pollinator-mediated competition influences selection for flower-color displacement in sympatric monkeyflowers.

When coflowering plant species share pollinators, pollinator-mediated competition may favor divergent floral characters associated with pollinator attraction. One potential outcome of this process is that sympatric populations will display increased divergence in floral traits compared with allopatric populations. We developed a new system to study the pattern and process of character displacement. In the central Sierra Nevada of California, USA, Mimulus bicolor is a spring wildflower with two flower-color morphs, one of which resembles coflowering M. guttatus. We documented a fine-scale geographic pattern of character displacement in sympatric and allopatric patches and, using experimental arrays, measured seed set in M. bicolor color morphs in the presence versus absence of M. guttatus. In sympatric arrays yellow, guttatus-like M. bicolor morphs had lower relative fitness (0.35 ± 0.05) and reduced conspecific pollen deposition compared with the distinct alternative morph, whereas in allopatric arrays yellow, guttatus-like morphs were occasionally strongly favored. Pollinator-mediated competition with M. guttatus is consistent with ecological character displacement in M. bicolor and likely contributes to a geographic pattern of character displacement.

Ramsar Wetlands: Understanding Change in Ecological Character

Ramsar Wetlands: Understanding Change in Ecological Character

종자수명에 영향을 미치는 벼 유전자원의 형태적 · 생태적 특성

종자수명에 영향을 미치는 벼 유전자원의 형태적 · 생태적 특성

An eight-gene molecular phylogeny of the Kickxellomycotina, including the first phylogenetic placement of Asellariales

Kickxellomycotina is a recently described subphylum encompassing four zygomycete orders (Asellariales, Dimargaritales, Harpellales, Kickxellales). These fungi are united by the formation of disciform septal pores containing lenticular plugs. Morphological diversification and life history evolution has made the relationships within and among the four orders difficult to resolve on those grounds alone. Here we infer the phylogeny of the Kickxellomycotina based on an eight-gene supermatrix including both ribosomal rDNA (18S, 28S, 5.8S) and protein sequences (MCM7, TSR1, RPB1, RPB2, β-tubulin). The results of this study demonstrate that Kickxellomycotina is monophyletic and related to members of the Zoopagomycotina. Eight unique clades are distinguished in the Kickxellomycotina, including the four defined orders (Asellariales, Dimargaritales, Harpellales, Kickxellales) as well as four genera previously placed within two of these orders (Barbatospora, Orphella, Ramicandelaber, Spiromyces). Dimargaritales and Ramicandelaber are the earliest diverging members of the subphylum, although the relationship between these taxa remains uncertain. The remaining six clades form a monophyletic group, with Barbatospora diverging first. The next split divides the remaining members of the subphylum into two subclades: (i) Asellariales and Harpellales and (ii) Kickxellales, Orphella and Spiromyces. Estimation of ancestral states for four potentially informative morphological and ecological characters reveals that arthropod endosymbiosis might have been an important factor in the early evolution of the Kickxellomycotina.

The eco-social transformation of urban wetlands: A case study of Colombo, Sri Lanka

Recent studies in both the environmental sciences and geography highlight unforeseen ecological transformations occurring in eco-social landscapes. These transformations often result in ‘novel’ or ‘hybrid’ ecosystems that differ from the original ecosystems both in ecological character and social setting. However, little is known about the causes, consequences, and dynamics of such transformations in complex urban environments and the consequences for highly sensitive ecosystem types such as wetlands. This paper investigates the environmental history and recent ecological transformations in the urban wetlands of Colombo, Sri Lanka. Our methodology includes a combination of techniques from environmental history, wetland science and urban ecology. We investigate the ecological changes in the wetlands from colonial times to the present and establish relationships among wetland ecology (the hydro-soil-vegetation nexus), landscape change, community, and governance factors. We conclude that from 1980 onwards, the Colombo urban wetlands have undergone an overall transformation in both wetland type (composition and structure) and the social setting. Hydrological modification, watershed urbanization and the changes in ecosystem use were identified as the main causes of wetland transformation with the causes and consequences of the transformation having complex feedback loops. We synthesize these relationships into a post hoc conceptual model that will be of broader utility as a general framework to understand eco-social interactions in the governance of urban ecosystems.

Bayesian species delimitation can be robust to guide-tree inference errors.

Bayesian species delimitation can be robust to guide-tree inference errors.

The ecology of rivers with contrasting flow regimes: identifying indicators for setting environmental flows

Summary The scientific basis for setting environmental flows is still hampered by our incomplete understanding of flow–ecology relationships and how river ecology varies with flow regime. We conducted a study of six rivers in Tasmania (Australia), three perennial and three intermittent, measuring a range of abiotic, biotic and ecosystem process attributes over 2 years. Our intentions were to identify: (i) whether they had an ecology characteristic of their flow regime and (ii) whether certain ecological attributes were more responsive to flow regime than others, and therefore represented candidate indicators (for environmental flows or flow alteration) specific to each flow regime. Only a few abiotic variables showed any relationship with flow regime: banks were higher, pools shallower and sediments finer in perennial rivers, and water temperature was generally lower in perennial rivers. Although rarely measured, we found that productivity and net ecosystem metabolism were strongly related to flow regime, whereas food chain length did not vary between perennial and intermittent rivers. Multivariate, rather than univariate, metrics of biotic assemblages were more effective at distinguishing perennial and intermittent flow regimes, and this was consistent among riparian and instream vegetation, biofilm and macroinvertebrate assemblages. In contrast to expectations from the literature, fish assemblages were not strong indicators of flow regime, largely due to the relatively low diversity and abundance of the Tasmanian fish fauna. Our findings demonstrate that rivers with different flow regimes can support a distinctive ecology, and conventional metrics of ecological character may not be the most sensitive to flow regime. We provide a set of ecological attributes that can: (i) support extrapolation of flow–ecology relationships across rivers to regional scales, (ii) provide benchmarks for environmental flow and flow restoration objectives, (iii) indicate alterations to natural or existing flow regimes and (iv) be used to monitor and evaluate flow management actions.

Morphometry of Chara aspera, C. canescens, C. baltica var. baltica, C. baltica var. liljebladii and C. intermedia oospores: Local variation versus taxonomic differences

Oospores of charophytes allow species delineation in palaeoecology, but are rarely used for determination of recent taxa. Especially in the genus Chara there is no generally accepted catalogue of oospore characters and the existing determination keys do not include brackish water material. Parameters with discriminatory power by statistical analysis are required to exploit the potential of oospore morphometry for species identification. Taking into consideration the conflicting species concepts in use for charophytes, we propose to continue building a database providing information about the parent plant of each oospore, including geographical coordinates and morphological details. This database is used here for the first time to determine which oospore parameters discriminate brackish water charophyte taxa from Germany. The results are discussed in the context of the recent debate of the systematic status of these taxa. In relation to Chara baltica var. baltica (Hartman) Bruzelius 1824, Chara baltica var. liljebladii (Wallm.) R.D.W. 1853 and Chara intermedia A. Braun 1859, our results indicate that C. baltica var. liljebladii is within the variability range of C. baltica var. baltica. On the other hand, C. intermedia and C. baltica var. liljebladii appear better separated in the statistical analyses, but still these two taxa cannot be clearly segregated except for ecological characters as, e.g. habitat salinity and incrustation. The article also presents a method for reliable discrimination between oospores of Chara aspera Willd. 1809 and Chara canescens Desv. & Loisel. In Loisel. 1810.

The Correlated Random Walk and the Rise of Movement Ecology

Understanding why, how, and when animals move is essential to many areas of ecology and related fields. Indeed, key aspects of animal behavior, population genetics, biological control, predator–prey dynamics, ecosystem engineering, and conservation biology all hinge upon knowing what critters are moving from where to where in a landscape, including information on how quickly, how regularly, and by what route they travel. The complexities involved in such processes have spawned tremendous efforts in both field research (where goals include measuring and characterizing such movements) and theoretical research (where goals include exploring the nature and potential consequences of movement). Ecologists today routinely receive some training in both empirical and theoretical research, and in the role of statistical analyses and model fitting as a way of linking the two perspectives. However, that has not always been the case. Spatial questions in ecology were long an area where the gulf between theory and reality was particularly wide. In part, this was due to the additional mathematical challenges of spatial models, but it also due to the perhaps greater technological challenges of measuring and contextualizing animal movements.

Molecular phylogeny and biogeography of the fern genus Pteris (Pteridaceae).

Pteris (Pteridaceae), comprising over 250 species, had been thought to be a monophyletic genus until the three monotypic genera Neurocallis, Ochropteris and Platyzoma were included. However, the relationships between the type species of the genus Pteris, P. longifolia, and other species are still unknown. Furthermore, several infrageneric morphological classifications have been proposed, but are debated. To date, no worldwide phylogenetic hypothesis has been proposed for the genus, and no comprehensive biogeographical history of Pteris, crucial to understanding its cosmopolitan distribution, has been presented. A molecular phylogeny of Pteris is presented for 135 species, based on cpDNA rbcL and matK and using maximum parsimony, maximum likelihood and Bayesian inference approaches. The inferred phylogeny was used to assess the biogeographical history of Pteris and to reconstruct the evolution of one ecological and four morphological characters commonly used for infrageneric classifications. The monophyly of Pteris remains uncertain, especially regarding the relationship of Pteris with Actiniopteris + Onychium and Platyzoma. Pteris comprises 11 clades supported by combinations of ecological and morphological character states, but none of the characters used in previous classifications were found to be exclusive synapomorphies. The results indicate that Pteris diversified around 47 million years ago, and when species colonized new geographical areas they generated new lineages, which are associated with morphological character transitions. This first phylogeny of Pteris on a global scale and including more than half of the diversity of the genus should contribute to a new, more reliable infrageneric classification of Pteris, based not only on a few morphological characters but also on ecological traits and geographical distribution. The inferred biogeographical history highlights long-distance dispersal as a major process shaping the worldwide distribution of the species. Colonization of different niches was followed by subsequent morphological diversification. Dispersal events followed by allopatric and parapatric speciation contribute to the species diversity of Pteris.

바둑돌부전나비(Taraka hamada)의 야외 생태학적 특성 조사

2010년부터 2012년까지 전국 각지 야외에서 조사한 바둑돌부전나비의 생태학적 특성은 다음과 같다. 1. 이대에 서식하는 일본납작진딧물은 바둑돌부전나비 유충의 먹이로서 지표로부터 폭넓게 분포하였으며, 조사 8회 차인 6월 13일부터 밀도가 현저히 감소하였다. 2. 일본납작진딧물과 바둑돌부전나비가 가장 많은 밀도를 보이는 곳은 줄기와 가장 인접한 부위이었다. 3. 바둑돌부전나비의 유충 예상 령수는 4령으로 추측된다. 4. 바둑돌부전나비 성충의 야외 노출 시 생존시간 조사 결과, 2분 이내에 사망하는 것으로 조사 되었다. Taraka hamada is known as the sole aphidophagous lycaenid butterfly in Korea. The species specifically preys upon Ceratovacuna japonica which lives in bamboo forests. During several years, the species has been received attention from the field of industrial insects in order to commercialize as a pet. However, an ecological character of the species have been unclear in Korea. We carried out a survey for basic ecology and distribution of the two species for 2010 to 2012. As the results, both species only cohabit at Pseudosasa japonica in our investigation. C. japonica is widely distributed from the host plant. Population density of T. hamada is synchronized with the density changes of C. japonica. Their densities are gradually decreased from the point to the investigation and significantly declined in mid-june. The maximum population density of both species shows at the basal part of a leaf. The last-larval instar of T. hamada may seem to be reaching at <TEX>$4^{th}$</TEX> stage. The adults of T. hamada are killed within two minutes when they were exposed to the sun.

The pairwise approach to analysing species co‐occurrence

AbstractThe analysis of species co‐occurrence patterns continues to be a main pursuit of ecologists, primarily because the coexistence of species is fundamentally important in evaluating various theories, principles and concepts. Examples include community assembly, equilibrium versus non‐equilibrium organization of communities, resource partitioning and ecological character displacement, the local–regional species diversity relationship, and the metacommunity concept. Traditionally, co‐occurrence has been measured and tested at the level of an entire species presence–absence matrix wherein various algorithms are used to randomize matrices and produce statistical null distributions of metrics that quantify structure in the matrix. This approach implicitly recognizes a presence–absence matrix as having some real ecological identity (e.g. a set of species exhibiting nestedness among a set of islands) in addition to being a unit of statistical analysis. An emerging alternative is to test for non‐random co‐occurrence between paired species. The pairwise approach does not analyse matrix‐level structure and thus views a species pair as the fundamental unit of co‐occurrence. Inferring process from pattern is very difficult in analyses of co‐occurrence; however, the pairwise approach may make this task easier by simplifying the analysis and resulting inferences to associations between paired species.

Familial placement of Wightia (Lamiales)

The familial placement of Wightia has long been a problem. Here, we present a comprehensive phylogenetic inspection of Wightia based on noncoding chloroplast loci (the rps16 intron and the trnL–F region) and nuclear ribosomal internal transcribed spacer, and on chemical analysis. A total of 70 samples (including 51 genera from 13 families of Lamiales) were employed in a molecular study. Phylograms suggest that Wightia is sister to Paulownia or Phrymaceae; species tree shows Wightia and Paulownia are sister groups which clustered with Phrymaceae in an unresolved clade. Chemical evidence shows affinity of Wightia to Paulowniaceae. With the addition of morphological, palynological and ecological characters, we suppose a familial position of Wightia belonging to or close to Paulowniaceae. Brandisia (a member of Orobanchaceae) does not have a close relationship with Wightia.

Evolution of body shape in differently coloured sympatric congeners and allopatric populations ofLakeMalawi's rock‐dwelling cichlids

The cichlid fishes of Lake Malawi represent one of the most diverse adaptive radiations of vertebrates known. Among the rock-dwelling cichlids (mbuna), closely related sympatric congeners possess similar trophic morphologies (i.e. cranial and jaw structures), defend overlapping or adjacent territories, but can be easily distinguished based on male nuptial coloration. The apparent morphological similarity of congeners, however, leads to an ecological conundrum: theory predicts that ecological competition should lead to competitive exclusion. Hence, we hypothesized that slight, yet significant, ecological differences accompanied the divergence in sexual signals and that the divergence of ecological and sexual traits is correlated. To evaluate this hypothesis, we quantified body shape, a trait of known ecological importance, in populations of Maylandia zebra, a barred, widespread mbuna, and several sympatric nonbarred congeners. We found that the barred populations differ in body shape from their nonbarred sympatric congeners and that the direction of shape differences was consistent across all barred vs. nonbarred comparisons. Barred populations are generally deeper bodied which may be an adaptation to the structurally complex habitat they prefer, whereas the nonbarred species have a more fusiform body shape, which may be adaptive in their more open microhabitat. Furthermore, M.zebra populations sympatric with nonbarred congeners differ from populations where the nonbarred phenotype is absent and occupy less morphospace, indicating potential ecological character displacement. Mitochondrial DNA as well as published AFLP data indicated that the nonbarred populations are not monophyletic and therefore may have evolved multiple times independently. Overall our data suggest that the evolution of coloration and body shape may be coupled as a result of correlational selection. We hypothesize that correlated evolution of sexually selected and ecological traits may have contributed to rapid speciation as well as the maintenance of diversity in one of the most diverse adaptive radiations known.

Allometric Convergence, Acoustic Character Displacement, and Species Recognition in the Syntopic Cricket Frogs Acris crepitans and A. gryllus

Evidence for reproductive character displacement (RCD) has accumulated more slowly than for ecological character displacement, perhaps because sampling scales and environmental covariates can obscure the role of RCD in speciation. We examined an early example of RCD in an anuran species group, the vocalizations of the sympatric cricket frogs Acris crepitans and A. gryllus. With a relatively fine spatial scale, we compared mixed-species choruses (syntopy), nearby locations where A. gryllus is recently extirpated (historic sympatry), and surrounding areas without secondary contact (allopatry). In each of these areas, we evaluated variation in dominant frequency, click rate, and mass of males. In addition, we determined the acoustic preferences of syntopic females. Temperature influenced dominant frequency of vocalizations in A. crepitans, but not in A. gryllus. Body size varied more and had a stronger influence on dominant frequency in A. crepitans than in A. gryllus. Consequently, the decrease in mass of A. crepitans in syntopy resulted in convergence of body size and divergence of dominant frequencies of the two species. In contrast, dominant frequency of A. crepitans did not differ between historic sympatry and allopatry. Females of both species used fine temporal structure to discriminate between conspecific and heterospecific vocalizations and showed no preferences for dominant frequency. Chorus noise limited the ability of A. gryllus females to detect and discriminate vocalizations, so convergence in mass might have resulted from RCD in dominant frequency to reduce heterospecific acoustic interference. However, influences other than RCD might have caused syntopic convergence in body size.

Re-evaluation of the morphological variability of Microglossum viride and M. griseoviride sp. nov.

Studies in Microglossum viride (Pers.) Gillet revealed that the name was used incorrectly for two similar but different taxa. Analyses of morphological, ecological and molecular (sequences of ITS and LSU region of rRNA gene) characters of type and voucher specimens of M. viride and related taxa resulted in delimitation and description of a new species, Microglossum griseoviride V. Kučera, Lizoň & M. Tomšovský. Lectotypes of Geoglossum viride Pers., and epitype of Geoglossum viride are designated. Species Microglossum minus Velen. and Microglossum lutescens Boud. are confirmed to be conspecific to M. viride.

Insect Diversity of the Muni-Pomadze Ramsar Site: An Important Site for Biodiversity Conservation in Ghana

An inventory of species diversity of insects of the Muni-Pomadze Ramsar site, with special reference to species of conservation concern, was carried out as part of an evaluation of changes in the ecological character of the site, twenty years after designation. Samples were taken from two protected areas within the Ramsar site, in the wet (July), dry (January), and intermediate (June) seasons. Community diversity was characterized in terms of number of species accumulated, species richness, Shannon-Weiner indices of diversity, Pielou’s evenness, and Bray-Curtis similarity. A total of 134 families from 19 insect orders were recorded during the entire study period. Yenku Block A recorded the highest species richness (98) and the highest diversity index (14.97), corroborated by the highest Margalef index of 3.82 with a relatively even distribution of species (0.834) during the intermediate season, and recorded the lowest diversity (6.957) and species richness (41) during the dry season. On the whole, the Muni-Pomadzi Ramsar site showed a high diversity of insect species. The presence of species such as Junonia oenone and Papilio demodocus which are specialized in degraded habitats at Yenku Block A in large numbers is a clear indication of degradation of the forest, but the presence of forest species such as Salamis anacardii and Euphaedra crokeri is an indication that some parts of this reserve are still in good shape. A comparison of the butterfly species recorded with findings in a 1997 survey showed a marked increase in numbers from 75 to 130; this may be attributed to the habitat changes that have taken place at the site offering more diverse habitat types.

Inocybe aureocitrina (Inocybaceae), a new species of section Rimosae from Mediterranean evergreen oak forests

The new agaricoid species Inocybe aureocitrina, belonging to section Rimosae, is described and illustrated based on morphological and ecological characters. It is recognized by the pale citrine yellow when young to golden yellow or orange yellow pileus colour at maturity, habitat in evergreen oak calcareous forests and especially by the rather small spores, broadly ellipsoid and not reniform in profile. A comparison with the holotypes of two close taxa with yellowish colours, e.g. Inocybe obsoleta var. lutea and Inocybe fastigiata var. cerina, is presented. Illustrations of the macro- and micro-morphological features of this new species are given.

Water-quality issues in Ramsar wetlands

Wetland water chemistry, i.e. the concentrations of macro ions in the water, encompasses an important component of the ecological character of a wetland. Of these ions, nutrients play a very active role because they are exchanged between living organisms and the environment via cycling processes involving plants, animals and microbes in the ecosystem. Because many wetlands in agricultural or densely populated parts of the earth are subject to enlarged nutrient inputs, their ecological character may be affected. At the same time, nutrients are processed and retained from the through-flowing water. The present article summarises these aspects of water quality in wetlands and reflects on the development of guidance for managers of wetlands listed as internationally important under the Ramsar Convention. Protection of the water-chemistry characteristics as part of the ecological character of the wetland, consequences of nutrient loading and opportunities for nutrient retention and their limitations are critically evaluated.