Methods for ecological monitoring: Biological interactions in a rocky subtidal community

Whilst both abiotic and biotic factors affect communities, biological interactions are widely believed to be the most important factors structuring subtidal communities. Among the potential biological interactions a few “key ” species may regulate species fluctuations. A rocky subtidal community in the Oslofjord (Norway) has been investigated using stereophotography, field experiments and manipulations (settlement plates, scraping, cages). The purpose was to develop a method for biological monitoring of chronic pollution effects. Around 60 species were identified in the community. The most permanent occupants wereLithothamnion sp. (25–30% cover) andPomatoceros triqueter (ca. 20% cover). The most important fluctuation was induced by the rapid growth of the hydroidLaomedea longissima to a 100% cover in June and its rapid disappearance. Free space covered more than 30% except in the period with large hydroid occurrence. The most active settlement period was in summer and autumn. The most important predators observed wereCoryphella sp.,Asterias rubens andPasmmechinus miliaris.Coryphella grazed upon the hydroids andAsterias andPsammechinus foraged on settled organisms which resulted in an increase of free space. Predation and recruitment in that order are probably the two most important factors structuring the studied community. The “key ” species were therefore the three predators. A monitoring programme should concentrate on these predators and their influence on the success of recruitment and the abundance of hydroids and free space, since these species control the natural fluctuations in the studied community. The stereophotographic method combined with simple settlement-plate experiments seems suitable for such a monitoring programme.     

Two types of using of space in the resident common shrews <Emphasis Type="Italic">Sorex araneus</Emphasis> L.

The home range of resident animals is considered as “familiar area” including a “foraging area.” It has been revealed that the activity of an average animal unit in the “foraging area” could be approximated by normal distribution. Estimation of activity distribution in the “familiar area” (beyond the “foraging area”) was impeded by means of marking since it might be difficult to record distant movements, and the method does not provide an essential body of data. In the case of the common shrew Sorex araneus, the “familiar area” was estimated using pitfall as animals evade them in the known areal. The “foraging area” radius of the average shrew was taken to be 30 m (95% of the animal unit activity), the radius of “familiar area” was within the range of 180–240 m. The “foraging area” was expected to provide the animal with vital resources, and the “familiar area” reflects its need for exploratory activity.     

Small mammals at the southeast of Tver oblast. Brief note 2. Diversity,population density and biomass

The analysis of biotic diversity using pictographs has shown various changes after long-term deforestation and under short-term disturbance of forest habitats. The biomass of small mammals was similar in all types of forest habitats; it was higher in meadows and dropped in the young (9-year) forest in the former field. The total biomass of settled and nonresident population has been considered. Though the numbers of species as well as the diversity structure vary, the biomass of settled population is similar in all types of forest habitats. Nonresident population contributes to general biomass the more the greater habitat is disturbed. The relevant sustainability of general biomass is considered in terms of biocenotic compensation. Biocenosis is regarded as a system having an inclination to “autonomous” functioning.     

Experiences of a Non-Governmental Organisation (NGO) dedicated to the conservation of Arctic char <Emphasis Type="Italic">Salvelinus alpinus</Emphasis> in Ireland

Podocopid ostracods have a calcified carapace encasing their uncalcified body parts like an envelope. A marginal infold (calcified inner lamella) develops along the free margin of both valves, notably in the adult stage. Radial pore canals, which often exhibit a distinct branched shape, can be seen in the free margin and they connect to the space between the outer and inner calcified cuticles called “vestibule.” These characters associated with the marginal infold have been recognized as important criteria both taxonomically and anatomically, but the calcification process of the marginal infold has never been investigated. In this study, we observed the calcification process of the anterior free margin in Leptocythere species. The free margin of the adult specimen starts its calcification just after ecdysis, but the degree of calcification remains the same as in the juvenile until approximately 35 h after ecdysis. The marginal infold of the adult specimen then begins to calcify from its distal part around 40 h postecdysis, and short simple pore canals can still be observed in the free margin. Marginal pore canals become more branched and narrower as calcification proceeds beyond 100 h postecdysis. These results indicate that the calcification of the free margin in a podocopid carapace occurs in two steps, and needs much time to complete the process even in small species of Leptocythere. In addition, these observations provide a basis for discussion on the correlation of the carapace size, environmental factors of the habitat, and the development of the vestibule in some Krithe species, “Krithe problem.”     

Spread of information through a population with socio-structural bias: I. Assumption of transitivity

A previously derived iteration formula for a random net was applied to some data on the spread of information through a population. It was found that if the axon density (the only free parameter in the formula) is determined by the first pair of experimental values, the predicted spread is much more rapid than the observed one. If the successive values of the “apparent axon density” are calculated from the successive experimental values, it is noticed that this quantity at first suffers a sharp drop from an initial high value to its lowest value and then gradually “recovers”. An attempt is made to account for this behavior of the apparent axon density in terms of the “assumption of transitivity”, based on a certain socio-structural bias, namely, that the likely contacts of two individuals who themselves have been in contact are expected to be strongly overlapping. The assumption of transitivity leads to a drop in the apparent axon density from an arbitrary initial value to the vicinity of unity (if the actual axon density is not too small). However, the “recovery” is not accounted for, and thus the predicted spread turns out to beslower than the observed.     

Transient behaviour of the single loop solute cycling model of the renal medulla

Transient solutions are developed for the buildup of a concentration gradient in the single loop solute cycling model of the renal medulla. The “pump” from ascending limb to descending limb is considered in both unsaturated and completely saturated modes of operation. Both analytic solutions and semianalytic solutions obtained from inverting Laplace transforms are considered. The classic representation of concentration buildup by the multiplication process is compared with calculated profiles. The “single effect” is found to vary both in time and space.     

Group formation and anemone use in captively reared anemonefish (<Emphasis Type="Italic">Amphiprion frenatus</Emphasis>)

We studied group formation and anemone use in captively reared anemonefish Amphiprion frenatus. Four small fish (23–32 mm total length) were simultaneously released into a central area of the aquaria (ca. 160 l) that was divided in half with an anemone placed on each half, with the opportunity to settle on either side. Four-day trials were conducted for analyzing settlement patterns. Because of the monogamous mating system, we predicted that small fish should settle in pairs. However, all four small fish settled on the same side in 7 of 14 replicates, which was a higher than expected value under random settlement.     

Responses of mobile epifauna to small-scale seagrass patchiness: is fragmentation important?

Habitat fragmentation is a process involving splitting of continuous habitats into smaller, and more isolated habitat patches. To assess the effects of small-scale habitat patchiness and isolation without the confounding effect of habitat loss on benthic macrofauna, two field experiments were conducted in the Archipelago Sea, SW Finland. Using artificial seagrass units (ASUs) we contrasted continuous patches (“C”) with fragmented patches (“F”) of the same combined area as the continuous patches. The fragmentation treatment involved two isolation distances (0.5 and 3.0 m) between the ASUs (“F 0.5”) and (“F 3.0”). This design was repeated in two consecutive experiments where the patch area was 0.25 and 0.0625 m², respectively. Mobile epifauna were allowed to colonize patches for 12 days in both experiments. In both experiments, the total epifaunal density was significantly higher in the “F 0.5” treatment than in the “C” treatment, and the three dominant taxa showed positive or neutral responses to the habitat configuration. No fragmentation effect on the number of species was detected in either of the experiments, but fragmentation had a negative effect on the epifaunal diversity (Shannon’s H′) in the experiment with the largest patch area. Epifaunal diversity was significantly lower in “F 3.0” treatment than in “C” or “F 0.5” treatments in the first experiment, indicating stronger effect of isolation instead of fragmentation per se. Edge effects were indirectly tested by comparing epifaunal densities with patch edge:area ratios. The results suggest that edge effects may have a more important role than patch size for the total densities of epifaunal taxa, and that small, isolated patches have equal or higher habitat value compared to larger fragments.     

A mathematical study of non-equimolar ternary gas diffusion

In view of the increasing evidence that multicomponent diffusion effects could be significant in biological gas exchange systems, a non-equimolar film model of multicomponent diffusion was derived. “Osmotic” ternary diffusion was studied for the gas systems He−N₂−O₂, He−SF₆−O₂, and N₂−SF₆−O₂. Diffusional fluxes and concentration profiles were calculated under both the “square-root” and the “product” flux conditions. Results were also compared with those obtained using the equimolar flux condition. It was found that the greater the difference of the diffusibilities between the two active components in a system, the greater the osmotic fluxes, and also the more alinear the concentration profiles. These results support the suggestion that the “product” condition applies to molecular diffusion in free space, the “square-root” condition to molecular diffusion in pores, and the equimolar flux condition to closed diffusion systems.     

Assessment of the Neva Estuary ecosystem state on the basis of structural characteristics of benthic animal communities in 1994–2005

In the years 1994–2005, the values of the integrated index IP’ at some stations of the Neva Bay changed from 38.1 to 81.9%, water quality changed from class 3 to class 5, and the states of some areas of the ecosystem that were evaluated as “tense” went to “catastrophic.” The integrated mean assessment of water quality according to the IP’ index over the entire Neva Bay throughout 12 years (1994–2005) remained relatively stable, waters were assessed as “polluted” (fourth class), and the state of the ecosystem was considered “critical.” The state of the eastern part of the Gulf of Finland in 1994–2005 was less favorable. The species diversity of zoobenthos in the resort zone of the eastern part of the Gulf of Finland is considerably lower than in the Neva Bay. Waters of the resort zone of the eastern part of the Gulf of Finland in 1994–2005 were assessed as one class lower than in the Neva Bay, i.e., as “polluted-dirty” (fourth-fifth class), and the state of the ecosystem was assessed as being in a “crisis.” In the resort zone, there was a decline in species diversity and abundance and biomass of benthic animals; i.e., all characteristics of the degradation of benthic animal communities were observed.     

Monitoring and manipulation of a sublittoral hard bottom biocoenosis in Balsfjord,northern Norway

Sublittoral hard bottom biocoenoses in Balsfjord, Norway (69°31′ N, 19°1′ E), were monitored using underwater stereophotogrammetry. The study includes manipulation of natural densities of organisms and testing the importance of biological interactions and “key species ” for the structure of biocoenoses. Underwater photography has the advantages of being a non-destructive method, but it is selective because small or hidden organisms cannot always be observed. Field experiments with exclusion of organisms from cages seem suitable for testing hypotheses concerning which animals are “key species ” in certain biocoenoses. Sea-urchins(Strongylocentrotus droebachiensis, S. pallidus) were suspected to be “key species ” in the present study, and their removal from cages caused an increase in abundance of barnacles(Balanus balanoides), the limpetAcmaea testudinalis and algal cover.     

Elongated microvilli support the sea urchin embryo concentrically within the perivitelline space until hatching

Summary The early sea urchin embryo is supported in a concentric position within the perivitelline space by elongated microvilli which are attached to the fertilization envelope by extracellular matrix fibers. This “attachment complex,” of microvillus tip: extracellular matrix fibers: fertilization envelope, was revealed by two methods: the use of pronase or calcium-free sea water to dissolve the extracellular matrix fibers, thus causing the eggs to lose their concentric location, and the visualization of the “attachment complex” using video-enhanced differential interference contrast microscopy and transmission electron microscope images. The presence of the “attachment complex” helps in understanding two types of early developmental events: (1) the apparently continual change in microvillus length during cleavage stages which retains the embryos in their concentric position and (2) the hatching process.     

Carbohydrate tolerance,serum albumin and protein values of normal and “waster” marmosets (Callithrix jacchus)

The major objective of this study was to establish standard glucose and lactose tolerance curves for the common marmoset (Callithrix jacchus). These data were utilized to establish criteria for detection of abnormal glucose tolerance and characterization of some aspects of the “marmoset wasting syndrome” which has been observed in this species. Glucose and lactose tolerance tests were performed on healthy animals and typical “marmoset wasters.” Eighteen normal animals were 18 to 36 months old and weighed 194–280 g. Six “wasters” were in the age range of 24 to 84 months and weighed 163–253 g. Seven experiments were carried out for each glucose tolerance test. In each trial it was observed that the serum glucose concentration (SGC) of the healthy animal after 90 min was two times higher than the pre-administration concentrations. The SGC returned to the pre-administration concentration within 150–300 min in animals administered glucose at dosages of 2 g/kg and 1 g/kg of body weight. However, at the dosage level of 5 g/kg body weight, the SGC of the animals tripled after 30 min and required 300 min to return to the pre-administration level. The 2 g/kg dosage level was chosen as typical. When similar experiments were conducted with animals identified as “chronic wasters,” all of the animals except one were observed to be inefficient in the absorption of glucose. When lactose was administered at a level of 4 g/kg, similar results were obtained. Normal and “waster” marmosets were also subjected to serum total protein, albumin and electrophoresis determinations in an effort to establish additional criteria that may be utilized in the identification of the “marmoset wasting” syndrome. Serum albumin was significantly higher in the “waster” marmosets 30 min following an oral administration of glucose than was observed in normal animals. Total protein values were not significantly lower in the “wasters” when subjected to the same tolerance test. The albumin level in normal animals was not affected by similar glucose tolerance tests. The electrophoretic patterns of serum protein for normal animals exhibited more bands than was observed in patterns of serum protein for “waster” marmosets. From these data, it seems logical that these diagnostic tests may be useful in developing a profile for the early detection of the “wasting” syndrome in marmosets.     

Decline in energy storage in the Antarctic minke whale (<Emphasis Type="Italic">Balaenoptera bonaerensis</Emphasis>) in the Southern Ocean

The annual trend in energy storage in the Antarctic minke whale was examined using catch data from all 18 survey years in the Japanese Whale Research Program (JARPA). Regression analyses clearly showed that blubber thickness, girth and fat weight have been decreasing for nearly 2 decades. The decrease per year is estimated at approximately 0.02 cm for mid-lateral blubber thickness and 17 kg for fat weight, corresponding to 9% for both measurements over the 18-year period. Furthermore, “date”, “extent of diatom adhesion”, “sex”, “body length”, “fetus length”, “latitude”, “age” and “longitude” were all identified as partially independent predictors of blubber thickness. The direct interpretation of this substantial decline in energy storage in terms of food availability is difficult, since no long-term krill abundance series is available. However, an increase in the abundance of krill feeders other than minke whales and a resulting decrease in the krill population must be considered as a likely explanation.     

Age changes of the carpal bones in macaques: Application of the fourier analysis on the radiographs

A method based on the Fourier analysis is proposed, which describes and analyzes the contour morphology of carpal bones by separating morphology into factors of shape and size. Here, “size” refers to the average diameter of the contour. The “shape” is expressed byshape factors which are derived from the Fourier series and the “shape” of a monkey is expressed by ashape index which is calculated fromshape factors. The age change in the morphology of the lunate and capitate ofMacaca fuscata fuscata was analyzed by this method. The development of “shape” approximately completes by 3 years of age, whereas increase in “size” begins its spurt at that age as do body weight and anterior trunk length. By applying this method to other macaque species, it was found thatM. mulatta, M. f. yakui andM. cyclopis exhibit similar patterns of growth and development of carpal bones to those ofM. f. fuscata. Patterns found inM. fascicularis differ in that its bones develop faster than in the other macaques with respect to the “shape,” but remain small with respect to the “size.”     

Male parasitism and intrasexual competition in a burrowing barnacle

Summary In sexually dimorphic animals, large male body size is often associated with direct interference competition among males for access to females or resources used in reproduction. In constrast, small male body size may be associated with indirect scramble competition among males for temporal or spatial access to females. Minute, “parasitic” males of the acrothoracican barnacleTrypetesa lampas (Hancock) appear to compete with one another for permanent attachment sites on the external body of the female. Several spatial patterns suggest indirect male-male competition: 1) males were consistently aggregated on the anterior surface of the female ovarian disc; 2) the average distance from attached males to the site of insemination correlated positively with local male density; 3) average male body size on a female decreased as a function of male density; 4) the distribution of males on the left and right hand sides of the female ovarian disc was more even than expected, suggesting that males avoided crowded settlement sites. The number of males attached to a female increased with female body size and matched a null model in which males colonized female “targets” of differing areas. These results suggest that competition between males primarily affected settlement sites and male body sizes within, rather than among, females. Male parasitism may have evolved through both sexual selection for efficient access to females (Ghiselin 1974) and natural selection for reduced burrow density in a space-limited habitat (Turner and Yakovlev 1983).     

Physiological bases of oligotrophy of microorganisms and the concept of microbial community

Three groups of physiological processes in microorganisms are considered the physiological basis of oligotrophy: the greater substrate affinity of the oligotrophs' transport systems, efficient or “economical” metabolism, and existence of a “master reaction” or “rate-determining steps” controlling the rate of metabolism. Heterotrophic microorganisms are divided into three unequal groups according to “reaction norma.” Two groups representing the extremes are small groups with the “narrow” reaction norma, regarding the concentrations and structure of the assimilated organic compounds and variability limits of the physiological characteristics mentioned above. The third, intermediate group includes the majority of microorganisms with the “wide” reaction norma.     

Hexadecanoid pathway in plants: Lipoxygenase dioxygenation of (7<Emphasis Type="Italic">Z</Emphasis>,10<Emphasis Type="Italic">Z</Emphasis>,13<Emphasis Type="Italic">Z</Emphasis>)-hexadecatrienoic acid

7,10,13-Hexadecatrienoic acid (16:3) is abundant in many plant species. However, its metabolism through the lipoxygenase pathway is not sufficiently understood. The goal of present work was to investigate the oxygenation of 16:3 by different plant lipoxygenases and to study the occurrence of oxygenated derivatives of 16:3 in plant seedlings. The recombinant maize 9-lipoxygenase specifically converted 16:3 into (7S)-hydroperoxide. Identification of this novel oxylipin was substantiated by data of GC-MS, LC-MS/MS, ¹H-NMR, and 2D-COSY as well as by deuterium labeling from [²H₆]16:3. Soybean lipoxygenase 1 produced 91% (11S)-hydroperoxide and 6% racemic 14-hydroperoxide. Recombinant soybean lipoxygenase 2 (specifically oxidizing linoleate into 13-hydroperoxide) lacked any specificity towards 16:3. Lipoxygenase 2 produced 7-, 8-, 10-, 11-, 13-, and 14-hydroperoxides of 16:3, as well as a significant amount of bis-allylic 9-hydroperoxide. Seedlings of several examined plant species possessed free hydroxy derivatives of 16:3 (HHTs), as well as their ethyl esters. Interestingly, HHTs occur not only in “16:3 plants”, but also in typical “18:3 plants” like pea and soybean seedlings.     

From “Us vs. Them” to “Shared Risk”: Can Animals Help Link Environmental Factors to Human Health?

Linking human health risk to environmental factors can be a challenge for clinicians, public health departments, and environmental health researchers. While it is possible that nonhuman animal species could help identify and mitigate such linkages, the fields of animal and human health remain far apart, and the prevailing human health attitude toward disease events in animals is an “us vs. them” paradigm that considers the degree of threat that animals themselves pose to humans. An alternative would be the development of the concepts of animals as models for environmentally induced disease, as well as potential “sentinels” providing early warning of both noninfectious and infectious hazards in the environment. For such concepts to truly develop, critical knowledge gaps need to be addressed using a “shared risk” paradigm based on the comparative biology of environment–host interactions in different species.     

Polymorphism of canonical and noncanonical <Emphasis Type="Italic">gypsy</Emphasis> sequences in different species of <Emphasis Type="Italic">Drosophila </Emphasis><Emphasis Type="Italic">melanogaster</Emphasis> subgroup: possible evolutionary relations

Mobile genetic elements constitute a substantial part of eukaryotic genome and play an important role in its organization and functioning. Co-evolution of retrotransposons and their hosts resulted in the establishment of control systems employing mechanisms of RNA interference that seem to be impossible to evade. However, “active” copies of endogenous retrovirus gypsy escape cellular control in some cases, while its evolutionary elder “inactive” variants do not. To clarify the evolutionary relationship between “active” and “inactive” gypsy we combined two approaches: the analysis of gypsy sequences, isolated from G32 Drosophila melanogaster strain and from different Drosophila species of the melanogaster subgroup, as well as the study of databases, available on the Internet. No signs of “intermediate” (between “active” and “inactive”) gypsy form were found in GenBank, and four full-size G32 gypsy copies demonstrated a convergence that presumably involves gene conversion. No “active” gypsy were revealed among PCR generated gypsy ORF3 sequences from the various Drosophila species indicating that “active” gypsy appeared in some population of D. melanogaster and then started to spread out. Analysis of sequences flanking gypsy variants in G32 revealed their predominantly heterochromatic location. Discrepancy between the structure of actual gypsy sites in G32 and corresponding sequences in database might indicate significant inter-strain heterochromatin diversity. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.