Microbial expansion following faunal mass extinctions in Earth history can be studied by petrographic examination of microbialites (microbial crusts) or well-preserved organic-walled microbes. However, where preservation is poor, quantification of microbial communities can be problematic. We have circumvented this problem by adopting a lipid biomarker-based approach to evaluate microbial community ...

Recent debate regarding microbial biogeography has focused largely on free-living microbes, yet those microbes associated with host organisms are also of interest from a biogeographical perspective. Marine eukaryotes and associated bacteria should provide ideal systems in which to consider microbial biogeography, as (i) bacteria in seawater should be able to ...

Onchocerciasis is a chronic filarial infection transmitted by Simulium flies that has a focal geographical distribution in Latin America. The southern Venezuelan focus has a gradient of endemicity that includes the largest number of hyperendemic communities in the continent, many of them in remote forest and mountainous areas, where it ...

Present-day thought on the notion of species is troubled by a mistaken understanding of the nature of the issue: while the species problem is commonly understood as concerning the epistemology and ontology of one single scientific concept, I argue that in fact there are multiple distinct concepts at stake. An ...

Fifty-five paleolimnological records from lakes in the circumpolar Arctic reveal widespread species changes and ecological reorganizations in algae and invertebrate communities since approximately anno Domini 1850. The remoteness of these sites, coupled with the ecological characteristics of taxa involved, indicate that changes are primarily driven by climate warming through lengthening ...

Riparian vegetation, which normally differs structurally and compositionally from surrounding vegetation, has been degraded in many parts of the fynbos biome by several species of invasive Australian <i>Acacia</i>. Systematic clearing of dense stands of these alien trees was initiated in 1995, and information is urgently needed to guide the restoration ...

To locate their hosts, parasitic wasps can 'eavesdrop' on the intraspecific chemical communications of their insect hosts. Here we describe an example in which the information exploited by the parasitic wasp Trichogramma brassicae is a butterfly anti-aphrodisiac that is passed from male to female Pieris brassicae butterflies during mating, to ...

The ITS region including the 5.8S rRNA gene as well as the 5' end of the 28S rRNA gene of hypogeous Pezizaceae and Tuberaceae were studied to clarify the generic placement of two southern African desert truffles, Terfezia pfeilii and Choiromyces echinulatus. The results show that neither species belongs in ...

Seven kairomone formulations (Trécé, Inc., Salinas, CA) were evaluated for their effectiveness as attractants for luring three species of cucumber beetles into Pherocon CRW traps (Trécé, Inc.) in cucurbit and sweetpotato fields. The spotted cucumber beetle, Diabrotica undecimpunctata howardi Barber; the banded cucumber beetle, Diabrotica balteata LeConte; and the striped ...

Various test strategies are in use in ecotoxicology to assess the potential risks of toxicants on aquatic communities. The species-sensitivity distribution concept (SSD) works by arranging single-species laboratory test data in a cumulative frequency distribution. The pollution-induced community tolerance concept (PICT) uses observable community responses by measuring increases in community ...

Natural floodplains play an essential role in the processing and decomposition of organic matter and in the self-purification ability of rivers, largely due to the activity of bacteria. Knowledge about the composition of bacterial communities and its impact on organic-matter cycling is crucial for the understanding of ecological processes in ...

Laelaps neacomydis n. sp. is described from the pelage of the rodent Neacomys spinosus collected in Bolivia. Collection records from northern Brazil, southeastern Peru, and central Bolivia indicate its wide distribution across Amazonas associated with rodents of the genus Neacomys. The formal taxonomic description and illustrations are derived from the ...

A knowledge of the nesting requirements of R&uuml;ppell's Parrot can aid its conservation. Nests were found during 17 months of fieldwork in Namibia and characteristics of the sites are reported here. Nests were found in woodpecker cavities. 72% of the nests were in three tree species: <i>Faidherbia</i><i> albida</i>,<i> Acacia erioloba ...

BACKGROUND: and Aims The four cultivated Erythroxylum taxa (E. coca var. coca, E. novogranatense var. novogranatense, E. coca var. ipadu and E. novogranatense var. truxillense) are indigenous to the Andean region of South America and have been cultivated for folk-medicine and, within the last century, for illicit cocaine production. The ...

The rust fungus <i >Aecidium macowanianum</i> Thüm. occurring on <i >Conyza</i> species (Asteraceae), is transferred to the genus <i >Endophyllum</i> Lèv., as the new combination <i >Endophyllum macowanianum</i> (Thüm.) A.R. Wood. This species should not be confused with the similarly named <i >E. macowanii</i> Pole Evans occurring on <i >Rhamnus ...

Deep hypersaline anoxic basins in the Mediterranean Sea are a legacy of dissolution of ancient subterranean salt deposits from the Miocene period. Our study revealed that these hypersaline basins are not biogeochemical dead ends, but support in situ sulfate reduction, methanogenesis, and heterotrophic activity. A wide diversity of prokaryotes was ...

It is 20 years since Munro and Scott identified the causes and possible remedies for the dissipation of rents in fisheries. We analyse one of the solutions proposed by Munro and Scott by using insights from the British Columbia multi-species groundfish trawl fishery that has used ITQs since 1997. The ...

A four-year study of species composition of the zooplankton community was conducted at Lagoa Comprida, a coastal lagoon. Forty-two species of rotifers were recorded and illustrated. All rotifer species, except Lecane boettgeri Koste, 1986 and Macrochaetus kostei, Jose de Paggi, Branco & Kozlowsky-Suzuki, 2000, have already been found in other ...

This paper presents the results of a proposed intervention to deal with the odor problems of a sewage treatment works (STW), which is located near a populated area. The STW consists of a facultative pond. Since this pond functions under close to anaerobic conditions, unpleasant odors are emitted. In this ...

Diatoms, which are early autotrophic colonisers, are an important constituent of the biofouling community in the marine environment. The effects of substratum and temporal variations on the fouling diatom community structure in a monsoon-influenced tropical estuary were studied. Fibreglass and glass coupons were exposed every month for a period of ...

Illustrated keys for the identification of the fourth-instar larvae and adult females of the mosquito genera Culex and Lutzia is presented, along with information on the geographic distribution of each species, and bionomics. Eighty-two species belonging to subgenera Culex, Culiciomyia, Eumelanomyia, Lophoceraomyia, and Oculeomyia of genus Culex, and three species ...

Two sites located in the sublittoral fine-sand macrobenthic community of the Ares-Betanzos Ria were sampled over four years (December 1992-November 1996) in the wake of the Aegean Sea oil spill. This sampling revealed that the petroleum had affected the structure and abundance of this community, as well as the number ...

Ectomycorrhizal fungal communities can be structured by abiotic and biotic factors. Here, we present evidence for community structuring by species interactions. We sampled ectomycorrhizas and forest floor seven times during a 13-month period. The presence of various ectomycorrhizal fungal species was determined for each sample, and species co-occurrence analyses were ...

With the growing capacity to inventory microbial community diversity, the need for statistical methods to compare community inventories is also growing. Several approaches have been proposed for comparing the diversity of microbial communities: some adapted from traditional ecology and others designed specifically for molecular inventories of microbes. Rarefaction is one ...

This paper reviews the application of species richness estimators to microbial diversity data and describes phylogenetic approaches to comparing microbial communities. The techniques are demonstrated using a community of marine actinobacteria. Results demonstrate that marine environments harbour massive actinobacterial diversity. Furthermore, these predictions are likely to be severe underestimates due ...

Bacteria and phytoplankton dynamics are thought to be closely linked in coastal marine environments, with correlations frequently observed between bacterial and phytoplankton biomass. In contrast, little is known about how these communities interact with each other at the species composition level. The purpose of the current study was to analyze ...

Pheromonal communication is the most convenient way to transfer information regarding gender and social status in animals of the same species with the holistic goal of sustaining reproduction. This type of information exchange is based on pheromones, molecules often chemically unrelated, that are contained in body fluids like urine, sweat, ...

The impact of riparian land use on the stream insect communities was studied at Kudremukh National Park located within Western Ghats, a tropical biodiversity hotspot in India. The diversity and community composition of stream insects varied across streams with different riparian land use types. The rarefied family and generic richness ...

The Catenella caespitosa (Withering) L.M. Irvine community at two stations on the Slovenian coast of the northern Adriatic Sea was sampled monthly during 2002. The flora consisted of 18 species: seven Chlorophyceae, five Rhodophyceae, two Fucophyceae, and four Cyanobacteria. The diversity index indicated low community complexity at both stations (0.8 ...

The intestinal helminth communities of 8 horses, 12 donkeys, 21 Hartmann's mountain zebras, and 44 Burchell's zebras were compared using the original data from 6 studies in South Africa and Namibia. Necropsy and worm recovery techniques were comparable between the studies. Sixty helminth species (58 nematode, 1 cestode, and 1 ...

The search by naturalists for good characters upon which to base both classifications and determinations of species led some 19th century entomologists to put their faith in insect genitalia as a criteria by which they could differentiate between and classify forms. Karl Jordan was such an entomologist, who turned to ...

An analysis was undertaken of intestinal helminth communities in flounder Platichthys flesus from two sites on the River Thames. A comparison was made between helminth community richness and diversity from these sites at the component and infracommunity levels. At the component community level, a richer and more diverse parasite community ...

The composition of the mesozooplanktonic community was studied in the Punta Morales estuary, Gulf of Nicoya, Pacific coast of Costa Rica, during 1997. Oblique plankton hauls were performed during high and low tide using a 280 microm mesh screen net equipped with a flowmeter. The community was characterized by holoplanktonic ...

Rapid changes in biodiversity are occurring globally, yet the ecological impacts of diversity loss are poorly understood. Here we use data from marine invertebrate communities to parameterize models that predict how extinctions will affect sediment bioturbation, a process vital to the persistence of aquatic communities. We show that species extinction ...

From 1995 up to the present, fish pens proliferated in the municipal waters of Bolinao, northern Philippines. Since then, fish kills and phytoplankton blooms have been recurrent. Have fishpens altered the phytoplankton community composition and production of these waters? The phytoplankton community in Cape Bolinao, Lingayen Gulf is typical of ...

We present here a study of European Neogene primate occurrences in the context of changing humidity. We studied the differences of primate localities versus non-primate localities by using the mammal communities and the ecomorphological data of the taxa present in the communities. The distribution of primates is influenced by humidity ...

The Australian fossil record shows that from ca. 25 Myr ago, the aseasonal-wet biome (rainforest and wet heath) gave way to the unique Australian sclerophyll biomes dominated by eucalypts, acacias and casuarinas. This transition coincided with tectonic isolation of Australia, leading to cooler, drier, more seasonal climates. From 3 Myr ...

Bacterioplankton community composition (BCC) was monitored in a shallow humic lake in northern Wisconsin, USA, over 3 years using automated ribosomal intergenic spacer analysis (ARISA). Comparison of ARISA profiles of bacterial communities over time indicated that BCC was highly variable on a seasonal and annual scale. Nonmetric multidimensional scaling (MDS) ...

A 2-yr, seasonal, parasitological study of 1,435 fish, belonging to 4 species of native fishes and 7 species of nonnative fishes from the lower Little Colorado River (LCR) and tributary creeks, Grand Canyon, Arizona, yielded 17 species of parasites. These comprised 1 myxozoan (Henneguya exilis), 2 copepods (Ergasilus arthrosis and ...

Ecological theory predicts that competition for a limiting resource will lead to the exclusion of species unless the within-species effects outweigh the between-species effects. Understanding how multiple competitors might coexist on a single resource has focused on the prescriptive formalism of a necessary niche width and limiting similarity. Here, we ...

Spottail shiner (Notropis hudsonius) from localities in each of the Great Lakes plus some nearby waterbodies, i.e., the St. Lawrence River, and the Chester River, Maryland, were examined for myxozoan parasites. A total of 10 species was found, including 7 histozoic (Myxobolus sp.; M. algonquinensis Xiao and Desser, 1997; M. ...

Completion of the Panama Canal in 1914 breached the continental divide and set into motion a natural experiment of unprecedented magnitude by bringing previously isolated freshwater fish communities into contact. The construction of a freshwater corridor connecting evolutionarily isolated communities in Pacific and Caribbean watersheds dramatically increased the rate of ...

Prey species that are unprofitable to attack often share conspicuous colours and patterns with other coexisting defended species. This phenomenon, termed müllerian mimicry, has long been explained as a consequence of selection on defended prey to adopt a common way of advertising their unprofitability. However, studies using two unpalatable prey ...

In southern Sweden, many wetlands have been constructed, and maintaining or increasing biological diversity is often included in the aims. Some wetlands are constructed near human settlements, thus raising the problem of wetlands being associated with mosquitoes (Diptera: Culicidae). Increased biodiversity (including mosquito diversity) is considered desirable, whereas mosquito nuisance ...

Investigating the role of intestinal microbial populations significantly relies on the assumption of stability. Therefore, the microbial community composition of the simulator of the human intestinal microbial ecosystem was qualitatively, quantitatively and functionally characterised during reactor start-up to evaluate its capacity to produce a stable bacterial community, representative for the ...

We study the problem of modeling species geographic distributions, a critical problem in conservation biology. We propose the use of maximum-entropy techniques for this problem, specifically, sequential-update algorithms that can handle a very large number of features.

The senescence and loss of photosynthetic and support structures is a nearly universal aspect of tree life history, and can be a major source of disturbance in forest understoreys, but the ability of falling canopy debris in determining the stature and composition of understorey communities seems not to have been ...

BACKGROUND: Community recovery following primary habitat alteration can provide tests for various hypotheses in ecology and conservation biology. Prominent among these are questions related to the manner and rate of community assembly after habitat perturbation. Here we use space-for-time substitution to analyse frog and lizard community assembly along two gradients ...

We studied epiphytic macrolichen communities in northern and central California to 1) describe how gradients in community composition relate to climate, topography, and stand structure and 2) define subregions of relatively homogeneous lichen communities and environmental conditions. Non-metric multidimensional scaling was used to characterize landscape-level trends in lichen community composition ...

Several important problems in ecology, evolution and conservation biology are affected by habitat selection in dispersing animals. Experience in the natal habitat has long been considered a potential source of variation in the habitat preferences displayed when dispersers select a post-dispersal habitat. However, the taxonomic breadth of this phenomenon is ...