Experimental evidence of minimal effects on octocoral hosts caused by the introduced ophiuroid Ophiothela mirabilis

Coral Reefs - Highly abundant and widespread populations of the introduced eastern Pacific ophiuroid brittle star Ophiothela mirabilis occur in southeast Florida, extending the range of this new...     

Experimental evidence for latent developmental plasticity: intertidal whelks respond to a native but not an introduced predator

Animals with highly inducible traits may show no inducible response when exposed to a related but wholly novel cue. This appears to be true for the intertidal whelk Nucella lamellosa faced with a voracious introduced predator. In the laboratory, we exposed whelks to effluent from two species of predatory crab, the native red rock crab Cancer productus and the invasive European green crab Carcinus maenas. Nucella and Cancer have a long shared history in the northeast Pacific, whereas potential interaction with Carcinus began here less than 10 years ago. Although Nucella responded adaptively to Cancer effluent by increasing shell thickness and decreasing somatic growth, there was no such response to Carcinus. Furthermore, thicker shelled Nucella were less likely to be eaten by Carcinus. Because Nucella produces thicker shells when exposed to Cancer cues, its ability to respond similarly to Carcinus depends only on the coupling of the Carcinus cue to the existing developmental pathways for adaptive changes in shell form. Such coupling of latent plasticity to a novel cue -- via genetic changes or associative learning -- could explain many cases of rapid phenotypic change following a sudden shift in the environment.     

Correction to: Widespread colonisation of Tanzanian catchments by introduced Oreochromis tilapia fishes: the legacy from decades of deliberate introduction

Hydrobiologia - Due to an unfortunate turn of events, four rows in Table 2 were transposed. Hence, the original article has been corrected. The corrected section (part of ‘Minor...     

Geographic distribution of Ophiothela brittle stars (Echinodermata: Ophiuroidea): substrate use plasticity and implications for the silent invasion of O. mirabilis in the Atlantic

Hydrobiologia - This study aimed to address the Ophiothela species distribution worldwide, report invasive populations, and investigate their association with benthic organisms through an...     

Vocal mimicry of hosts by Great Spotted Cuckoo Clamator glandarius: further evidence

Great Spotted Cuckoo nestlings were shown, after some days in the nest, to have begging calls that differed depending on whether they were being reared by Magpies or Carrion Crows. They also produced calls of a pitch and repetition rate that implied a high level of hunger.     

Experimental evidence of environmental effects on age-specific reproductive success: the importance of resource quality.

Age-specific access to high-quality resources (e.g. territory or nest site) might be an important determinant for improved reproductive performance with increasing age. I experimentally investigated the effects of territory quality versus other age-related improvements in breeding competence (e.g. foraging skills, breeding experience and local knowledge) on age-specific reproductive success. Territory quality (i.e. territory field layer height) was manipulated in year 2 of northern wheatears (Oenanthe oenanthe) that were breeding in the same territory in two consecutive years. Changing territory quality by changing field layer height had a strong effect on within-individual change in the reproductive success of wheatears. This effect was mainly due to a corresponding change in nest predation risk. When territory quality was kept constant (i.e. no between-year change in territory field layer height), within-individual reproductive success did not change between subsequent years. Thus, age-related improvements in foraging skills, breeding experience and local familiarity had no significant effect on within-individual changes in reproductive success. Increased reproductive success with increased age in northern wheatears is therefore mainly explained by an improved access to high-quality territories with increasing age. I conclude that age-dependent access to high-quality breeding resources might be a widespread phenomenon in nature.     

Edge effects and intraguild predation in native and introduced centipedes: evidence from the field and from laboratory microcosms

Human alteration of habitat has increased the proportion of forest edge in areas of previously continuous forest. This edge habitat facilitates invasion of exotic species into remaining fragments. The ability of native species to resist invasion varies and may depend on intrinsic variables such as dispersal and reproductive rates as well as external factors such as rate of habitat change and the density of populations of introduced species in edge habitat. We examined the distributional and competitive relationships of two members of the class Chilopoda, Scolopocryptops sexspinosus, a centipede native to the eastern US, and Lithobius forficatus, an exotic centipede introduced from Europe. We found that L. forficatus was most abundant in edge habitat and S. sexspinosus was most abundant in the interior habitat at our field sites. Although L. forficatus was present in habitat interiors at 11 of 12 sites, there was no correlation between fragment size and numbers of L. forficatus in interior habitat. The native centipede was rarely found occupying fragment edges. We used laboratory microcosms to examine potential competitive interactions and to indirectly assess prey preferences of the two species. In microcosms both species consumed similar prey, but the native centipede, S. sexspinosus, acted as an intraguild predator on the introduced centipede. Native centipedes were competitively superior in both intraspecific and interspecific pairings. Our results suggest that intraguild predation may aid native centipedes in resisting invasion of introduced centipedes from edge habitat.     

Canopy effects of octocoral communities on sedimentation: modern baffles on the shallow-water reefs of St. John,USVI

Coral Reefs - Recent shifts in the presence and abundance of species on shallow Caribbean coral reefs have left octocorals as the dominant functional group on some reefs, creating an ‘animal...     

Experimental comparative studies of the reactibility of lung tissue to intratracheally introduced ash produced by power plants

There was analysed the behaviour of the pulmonary tissue in white Wistar female rats exposed to a single effect of electroenergetic ashes from a few Polish power stations, hasting plants and electrohasting plants. The animals received a single 0.6 ml dose of the ashes in suspension of physiologic fluid intratracheally; 3 and 6 months after the experiment, the animals were decapitated and material for examinations was collected. Grains of used ashes were then assessed under the scanning electron microscope. Segments were stained with hematoxyline and cosine and by Masson's method. All the ashes caused inflammatory infiltrations, granulomas containing grains of the examined ash, fibrosis, thickening of interalveolar septa, atelectasis, and emphysema. The experiment resulted in a disturbance of biological balance of pulmonary connective tissue (stroma) due to the action of the ashes.     

Correction of intestinal dysbacteriosis in elderly patients with the use of bifidobacterin introduced by different routes

The results of the correction of disturbances in intestinal microflora in elderly patients with the use of bifidumbacterin in the form of powder or suppositories are presented. The effectiveness of the rectal administration of bifidumbacterin (by microinjections through an enema or in suppositories) is shown in comparison with the oral administration of the preparation. The administration of bifidumbacterin in suppositories for 15 days resulted in decreased content of hemolytic Escherichia below the threshold of determination in all examined patients.     

Cercosporoid hyphomycetes on malpighiaceous hosts from the Brazilian Cerrado: species of Pseudocercospora on hosts belonging to Byrsonima

Eleven new species of the genus Pseudocercospora were found on Byrsonima spp. from the Cerrado in Brazil: Pseudocercospora annellidica, P. byrsonimae-basilobae, P. byrsonimae-coccolobifoliae, P. byrsonimicola, P. byrsonimigena, P. campograndensis, P. grajauensis, P. mutabiliconidiophorum, P. pediformiconidiorum, P. planaltinensis, and P. subhyalina. The new species are described, illustrated and compared with hitherto described Pseudocercospora spp. on various hosts belonging to the Malpighiaceae, and all species concerned are keyed out.     

Morphological and ecological shifts in a land snail caused by the impact of an introduced predator

Introduced predators have become major threats to native animal species in oceanic islands. A number of studies have shown that alien predators have caused serious extinctions of island endemics. However, little attention has been paid to the evolutionary impacts of alien predators on native species. The present study shows that predation by black rats, Rattus rattus, has resulted in ecological and morphological changes in the land snail Mandarina anijimana from the island of Anijima in the Ogasawara archipelago. The frequency of empty predated shells has increased over the past 17–19 years in southern areas of the island. The shells of these snails were found to be significantly higher, smaller and darker in the survey in 2006 than in the survey in 1987–1989 performed in central and southern parts of Anijima, where predation by Rattus was serious. M. anijimana were formerly restricted to shallow broad-leaved litter, whereas they are currently found in deep palm litter, where predation pressure from Rattus may be lower. This suggests that increased predation pressure by Rattus has changed the habitat use of M. anijimana. The close association between shell morphology and habitat use of Mandarina species suggests that the habitat shift induced by the predation of Rattus has caused these changes in the shell morphology of M. anijimana over a period of 17–19 years.     

Correction to: How whale and dolphin barnacles attach to their hosts and the paradox of remarkably versatile attachment structures in cypris larvae

Organisms Diversity & Evolution - A typographical error was found in the Table 1 and Figures 5 and 9 legends. The specie name "Lepas anatifera" should have been "Lepas...     

Acetylcholine receptor-controlled ion translocation caused by phenyltrimethylammonium and nereistoxin: simple estimation of equilibrium constants of the minimal model

The rate of slow Li+ influx and the fraction of active form of acetylcholine receptor (AChR) of Electrophorus electricus membrane vesicles at equilibrium between the active and desensitized forms of the receptor were measured in the presence of various concentrations of phenyltrimethylammonium (PTA) and nereistoxin (NTX), by a simple filtration assay and flame emission spectroscopy. The equilibrium constants of these ligands in the minimal model, which accounts for the AChR-mediated ion flux, were estimated simply from these two measurements, since the equilibrium constants for acetylcholine (ACh) and carbamylcholine (Carb) estimated from two kinetic measurements agreed well with those estimated from five sophisticated kinetic measurements of AChR-mediated ion fluxes. PTA showed high potency but not high efficacy, and showed inhibition when large doses were applied. NTX showed both low potency and low efficacy and acted as an inhibitor when it was added with Carb. The apparent dissociation constants of these three agonists evaluated from the minimal model and the equilibrium constants agreed with those obtained by assay of inhibition of radiolabeled ligand binding.