Behaviour of female and pup grey seals Halichoerus grypus during the breeding period at Froan, Norway

We studied the behaviour of grey seals, Halichoerus grypus , during the breeding period at Froan, Norway, and compared our findings with existing studies on grey seals at breeding sites in Britain and Canada. The pups at Froan spent more time in water than pups at other breeding sites. While on-shore, the pups at Froan spent most of their time resting, behaviour similar to pups at other breeding sites. Lactating females at Froan spent most of their time in the sea, thus differing from females at most other breeding sites which spend most of their time on-shore. While in the sea, the females at Froan spent most time diving, typically interrupted by regular periods of surface swimming.     

Additional Information on the Relationship between Intra-specific Aggression and Anti-predator Behaviour in the Three-spined Stickleback,Gasterosteus aculeatus

18 non-breeding three-spined sticklebacks from a heavily predated site a further 24 fish from a predator-free site were screened for their responses to a realistic model pike. The behaviour of the same fish when confronted with a territorial intruder during the breeding season was also recorded, the two tests being carried out in random sequence and with an interval of at least 6 weeks. Multivariate analyses identified major behavioural dimensions in the pike test and in the intruder test, summarized by the labels ‘boldness’ and ‘aggression’ respectively. Sticklebacks from the heavily predated site were both less bold and less aggressive than those from the unpredated site. Levels of aggression for individuals within each population were positively correlated with their boldness scores, but only for the period when the subjects were recovering from a simulated predatory attack.     

Social Behaviour and Cooperative Breeding in Arctic Foxes,Alopex lagopus (L.), in a Semi-natural Environment

Most canid species show cooperative breeding at least occasionally. The helper-at-the-den system, when extra adults serve as helpers by feeding and guarding the cubs of an alpha pair, has been observed but not studied in any detail in wild Arctic foxes (Alopex lagopus). During a 3-months study of arctic foxes in two enclosures of 4 ha each, we measured the social behaviour during the reproductive season. Older foxes dominated younger ones and males dominated females of the same age. A litter with one surviving cub was born in one enclosure. The alpha male increased his rate of urine marking and barking and fed the alpha female both before and after the birth of the litter. However, about 10 days after the birth, the alpha female died. The cub was fed by his putative father, his sister and his brother (both one year old). The one year old female increased her rate of territorial defence, measured as urine marking and barking, when the mother died. The subordinate females were probably suppressed from breeding by the high aggression levels and territorial defence of the dominant females in each enclosure. The dominant female in the second enclosure came into heat after the death of the alpha female (her mother) in the first enclosure. These changes in behaviour can probably be explained by sexual inhibition by the alpha female while she was present. The significance of territorial defence and dominance, inbreeding avoidance, sexual suppression and evolution of helping behaviour are discussed.     

Genetic Diversity of Naturally Established Ectomycorrhizal Fungi on Norway Spruce Seedlings under Nursery Conditions

We have assessed ectomycorrhizal fungi colonizing Norway spruce (Picea abies L.) seedlings in nine forest nurseries using restriction fragment length polymorphism (RFLP) and sequencing analyses of the internal transcribed spacers (ITS1-5.8S-ITS2) amplicons. Restriction analysis of the amplified DNA fragments with HinfI, MboI, and TaqI enzymes allowed the definition of 17 RFLP genotypes; five of them could be unambiguously assigned to Thelephora terrestris, Hebeloma longicaudum, H. crustuliniforme, Tricharina ochroleuca, and Cenococcum geophilum species by comparison with the sporocarp RFLP-pattern database. The remaining genotypes have been sequenced and compared with sequences deposited in the GenBank database. The phylogenetic analysis of resulting sequences and their identified matches indicated that isolated genotypes have formed seven clades. The ascomycetes were predominant: we have determined eight species—Wilcoxina mikolae, Phialophora finlandia, Tuber sp., Cenococcum geophilum, Tricharina ochroleuca, Pulvinula constellatio, and two unidentified ascomycetes—whereas the basidiomycetes were less common (four species denoted: Amphinema byssoides, Hebeloma crustuliniforme, H. longicaudum, and Thelephora terrestris). Wilcoxina mikolae and Phialophora finlandia were the most frequent fungi. Analysis of variance revealed that ascomycetes abundance was higher in nurseries that used organic fertilizer.     

Respiratory Behaviour of Young Hinoki Cypress (Chamaecyparis obtusa) Trees under Field Conditions

Night-time respiration rates of aerial parts of six sample trees in a 9-year-old hinoki cypress [Chamaecyparis obtusa(Sieb. et Zucc.) Endl.] stand were measured at monthly intervals over a 1-year period, by an enclosed whole-tree method. When the relationships between annual respiration rate and mean phytomass, and between annual respiration rate and annual phytomass increment were examined, one sample tree, which was under stress, did not follow the trend of the rest, indicating that its lower respiration rate did not correspond to its size because of its negligible phytomass increment. Respiration was partitioned into maintenance and growth respiration to explain this phenomenon. The maintenance coefficients were 0.0345, 0.0373, 0.0352, 0.0211, 0.0316 and 0.0200g CO₂g^-1month^-1, in decreasing order of tree size. The maintenance coefficients of the stressed (i.e. 0.0211g CO₂g^-1month^-1) and suppressed (i.e. 0.0200g CO₂g^-1month^-1) trees were similar and smaller than those of the rest which were larger and alike, indicating that stress and suppression reduced the coefficient. The growth coefficients were 1.45, 1.51, 1.28, 1.80, 1.45 and 1.64g CO₂g^-1, in decreasing order of tree size. The growth coefficient of the stressed tree (i.e. 1.80g CO₂g^-1) was the largest followed by that of the smallest and suppressed tree (i.e. 1.64g CO₂g^-1), suggesting that stress and suppression reduced the efficiency of conversion of substrate into new structural phytomass. The stressed tree respired mainly to maintain itself. The respiratory behaviour of the sample trees, including the stressed tree, was compatible with the concept of growth and maintenance respiration.     

Morphology of Cymodocea serrulata from Yap,Micronesia, kept under controlled light conditions

Long-stemmed plants collected in subtidal beds in Tomil Harbor continued to develop short shoots that were elevated above the sediment under low light conditions (< 100 μM m^?2 s^?1), but produced stems that were horizontally orientated under higher light conditions (> 125 μM m^?2 s^?1). The direction of the growth of the stem could be altered by changing the light conditions, but only nodes initiated under the new light conditions showed a change in orientation. In contrast, plants from intertidal beds on Thursday Island, Queensland, Australia, produced only stems that were horizontally directed under diverse light conditions.     

Light Masking in the Field: An Experiment with Nocturnal and Diurnal Spiny Mice Under Semi-natural Field Conditions

Light masking has been studied almost exclusively in the laboratory. The authors populated four field enclosures with locally coexisting nocturnal Acomys cahirinus and diurnal A. russatus, and monitored their body temperatures (T_b) using implanted temperature-sensitive radio transmitters. A 3-h light pulse was initiated at the beginning of two consecutive nights; preceding nights were controls. A. cahirinus T_b and calculated activity levels decreased significantly during the light pulse, demonstrating a negative light masking response (light effect on T_b: ?0.32°C?±?0.15°C; average calculated activity records during the light pulse: 7?±?1.53, control: 9.8?±?1.62). Diurnal A. russatus did not respond to the light pulse. We conclude that light masking is not an artifact of laboratory conditions but represents a natural adaptive response in free-living populations. (Author correspondence: Shayroti@post.tau.ac.il)     

Ultradian Rhythm of Activity in Japanese Quail Groups under Semi-Natural Conditions during Ontogeny: Functional Aspects and Relation to Circadian Rhythm

The function of ultradian rhythms is not yet clearly elucidated. In particular, short-term rhythms are expressed during early ontogeny, especially in broods of precocial birds. We investigated the relationship between the clarity of the ultradian rhythm of the activity/rest cycle of a group of young Japanese quail (Coturnix japonica) and the level of social synchronisation and spatial cohesion between the birds within that group. The subjects were descended from two lines selected for either very pronounced rhythmic or arrhythmic circadian activity. We found a positive relationship between the clarity of the ultradian rhythm of the activity/rest cycle when birds were young and the clarity of the circadian rhythm of feeding activity when birds were older, but still immature. The temporal organisation of the behaviour of the chicks from these two lines was observed in outdoor aviaries, when they were 4, 8, 12 and 15 days old. The mean ultradian period expressed by groups of 12 chicks was variable, with a minimum of 6 minutes. The ultradian period lengthened regularly as chicks grew older, and reached approximately 40 min on day 15. The clarity of the ultradian rhythmicity of group activity was linked to the level of inter-individual social synchronisation and of spatial cohesion; the more pronounced the ultradian rhythms of a group, the greater the temporal and spatial cohesion of the chicks within the group. Moreover, these characteristics varied with the age of the chicks. Finally, chicks in the less rhythmic groups weighed less. These results stress the adaptive value of this temporal organisation strategy under natural conditions.     

Ultradian Rhythm of Activity in Japanese Quail Groups under Semi-Natural Conditions during Ontogeny: Functional Aspects and Relation to Circadian Rhythm

The function of ultradian rhythms is not yet clearly elucidated. In particular, short-term rhythms are expressed during early ontogeny, especially in broods of precocial birds. We investigated the relationship between the clarity of the ultradian rhythm of the activity/rest cycle of a group of young Japanese quail (Coturnix japonica) and the level of social synchronisation and spatial cohesion between the birds within that group. The subjects were descended from two lines selected for either very pronounced rhythmic or arrhythmic circadian activity. We found a positive relationship between the clarity of the ultradian rhythm of the activity/rest cycle when birds were young and the clarity of the circadian rhythm of feeding activity when birds were older, but still immature. The temporal organisation of the behaviour of the chicks from these two lines was observed in outdoor aviaries, when they were 4, 8, 12 and 15 days old. The mean ultradian period expressed by groups of 12 chicks was variable, with a minimum of 6 minutes. The ultradian period lengthened regularly as chicks grew older, and reached approximately 40 min on day 15. The clarity of the ultradian rhythmicity of group activity was linked to the level of inter-individual social synchronisation and of spatial cohesion; the more pronounced the ultradian rhythms of a group, the greater the temporal and spatial cohesion of the chicks within the group. Moreover, these characteristics varied with the age of the chicks. Finally, chicks in the less rhythmic groups weighed less. These results stress the adaptive value of this temporal organisation strategy under natural conditions.     

Behaviour of the chrysoflagellate alga,Dinobryon divergens,during lorica formation

Summary A timed series of light micrographs illustrates the process of lorica formation inDinobryon divergens. Analysis of this series reveals that theDinobryon cell forms the lorica in two distinct phases: First, the stalk region, without rotation of the cell, and second, the vaseshaped upper part of the lorica, with five slow rotations of the cell yielding the helicoidal band structure of the lorica. Complex changes of shape by the cell body provide the model for lorica diameter.     

Behaviour of the bark beetle, Ips grandicollis, during host selection

ABSTRACT. Equal numbers of dispersing Ips grandicollis adults were caught on sticky traps held on susceptible and resistant Pinus radiata trees. When beetles were attracted to the same set of trees using baits of ipsenol (aggregation pheromone), some of the beetles that landed on the boles of the trees bored into the bark. The subsequent response of the tree determined whether the tree was accepted or rejected. In resistant trees, the exudation of resin prevented continued boring and led to the retreat of the beetles. In susceptible trees, continued boring led to the establishment of the beetles. Ipsenol was not detected in males that retreated after boring into resistant trees. Beetles that bored into P. radiata logs obtained from slash, continued to bore into the bark, due to the absence of any of the resistance mechanisms; ipsenol was detected in such males. Extracts of groups of male beetles caught from the dispersing population on pheromone-baited traps, contained little or no ipsenol.     

Behaviour of leatherback sea turtles, Dermochelys coriacea, during the migratory cycle

Leatherback sea turtles, Dermochelys coriacea, undertake broad oceanic movements. While satellite telemetry has been used to investigate the post-nesting behaviour of female turtles tagged on tropical nesting beaches, long-term behavioural patterns of turtles of different sexes and sizes have not been described. Here we investigate behaviour for 25 subadult and adult male and female turtles satellite-tagged in temperate waters off Nova Scotia, Canada. Although sex and reproductive condition contributed to variation in migratory patterns, the migratory cycle of all turtles included movement between temperate and tropical waters. Marked changes in rates of travel, and diving and surfacing behaviour, accompanied southward movement away from northern foraging areas. As turtles approached higher latitudes the following spring and summer, they assumed behaviours consistent with regular foraging activity and eventually settled in coastal areas off Canada and the northeastern USA. Behavioural patterns corresponding to various phases of the migratory cycle were consistent across multiple animals and were repeated within individuals that completed return movements to northern waters. We consider the potential biological significance of these patterns, including how turtle behaviour relates to predator avoidance, thermoregulation and prey distribution.     

Cyanobacterial Blue Color Formation during Lysis under Natural Conditions

Cyanobacteria produce numerous volatile organic compounds (VOCs), such as β-cyclocitral, geosmin, and 2-methylisoborneol, which show lytic activity against cyanobacteria. Among these compounds, only β-cyclocitral causes a characteristic color change from green to blue (blue color formation) in the culture broth during the lysis process. In August 2008 and September 2010, the lysis of cyanobacteria involving blue color formation was observed at Lake Tsukui in northern Kanagawa Prefecture, Japan. We collected lake water containing the cyanobacteria and investigated the VOCs, such as β-cyclocitral, β-ionone, 1-propanol, 3-methyl-1-butanol, and 2-phenylethanol, as well as the number of cyanobacterial cells and their damage and pH changes. As a result, the following results were confirmed: the detection of several VOCs, including β-cyclocitral and its oxidation product, 2,2,6-trimethylcyclohexene-1-carboxylic acid; the identification of phycocyanin based on its visible spectrum; the lower pH (6.7 and 5.4) of the lysed samples; and characteristic morphological change in the damaged cyanobacterial cells. We also encountered the same phenomenon on 6 September 2013 in Lake Sagami in northern Kanagawa Prefecture and obtained almost the same results, such as blue color formation, decreasing pH, damaged cells, and detection of VOCs, including the oxidation products of β-cyclocitral. β-Cyclocitral derived from Microcystis has lytic activity against Microcystis itself but has stronger inhibitory activity against other cyanobacteria and algae, suggesting that the VOCs play an important role in the ecology of aquatic environments.     

Effects of Rearing Conditions on Behaviour and Endogenous Opioids in Rats with Alcohol Access during Adolescence

Causal links between early-life stress, genes and later psychiatric diagnoses are not possible to fully address in human studies. Animal models therefore provide an important complement in which conditions can be well controlled and are here used to study and distinguish effects of early-life stress and alcohol exposure. The objective of this study was to investigate the impact of rearing conditions on behaviour in young rats and if these changes could be followed over time and to examine interaction effects between early-life environment and adolescent alcohol drinking on behaviour and immunoreactive levels of the opioid peptides dynorphin B, met-enkephalin-Arg⁶Phe⁷ and beta-endorphin. We employed a rodent model, maternal separation, to study the impact of rearing conditions on behaviour, voluntary alcohol consumption and alcohol-induced effects. The consequences of short, 15 min (MS 15), and long, 360 min (MS 360), maternal separation in combination with adolescent voluntary alcohol consumption on behaviour and peptides were examined. A difference in the development of risk taking behaviour was found between the MS15 and MS360 while the development of general activity was found to differ between intake groups. Beta-endorphin levels in the pituitary and the periaqueductal gray area was found to be higher in the MS15 than the MS360. Adolescent drinking resulted in higher dynorphin B levels in the hippocampus and higher met-enkephalin-Arg⁶Phe⁷ levels in the amygdala. Amygdala and hippocampus are involved in addiction processes and changes in these brain areas after adolescent alcohol drinking may have consequences for cognitive function and drug consumption behaviour in adulthood. The study shows that individual behavioural profiling over time in combination with neurobiological investigations provides means for studies of causality between early-life stress, behaviour and vulnerability to psychiatric disorders.     

Comparative Analysis of Vestibular System Development in Various Groups of Mammals Living under Different Environmental Conditions

We have conducted for the first time a comparative study of the prenatal development of the vestibular system in representatives of pinnipeds (Phocidae, Otariidae, Odobenidae) and cetaceans (Odontoceti, Mysticeti) in comparison with terrestrial mammals. This allowed us to perform a detailed study of the structural organization of the inner ear in species with different ecological specialization, to find out adaptive aspects and stages of the formation of cochlear and vestibular structures in each of the studied species, and to correlate it with the properties of the environment. Studies on early embryogenesis of the labyrinth in cetaceans and pinnipeds, which represent a special direction in the evolution of placentates, give a significant contribution to the solution of the problem of the evolutionary origin of the labyrinth in the mammals studied. Sensory systems clearly demonstrate the scope of evolutionary and adaptive transformations, which appear in mammals during the transition from the terrestrial to the aquatic mode of life. At the same time, these results may provide help in understanding the general trends of the development of structure and function of the inner ear in mammals as a whole.     

Behaviour of nucleolus during mitosis

The aim of the present work was to study the distribution and the behaviour of the silver-staining nucleolar organizer region (Ag-NOR) proteins at the ultrastructural level during interphase and mitosis in five human and murine cancerous cell lines each characterized by a typical nucleolar morphology. During interphase the Ag-NOR proteins are restricted to the fibrillar centres (F.C.) and/or to the dense fibrillar component (D.F.C.). During prophase the silver-staining components come into close contact with some chromosomes and are arranged with a typical polarity: chromosome, F.C. and D.F.C. Then F.C. and D.F.C. together form roundish silver-stained structures and integrate in part within indentations at the periphery of the metaphase chromosomes. During anaphase and telophase large and small spherical silver-staining structures may be seen. They correspond respectively to the metaphase NORs and to numerous structures which appear de novo within ribonucleoprotein (RNP) material localized between the chromosomes. During late telophase the number of the small silver-staining structures decreases whereas the size of the larger ones increases. Then the interphase nucleoli recover their typical shape. These results suggest that when rRNA synthesis is impaired during mitosis the inactive NORs assume a structure and a localization which are not typical of the cell line. In contrast the F.C. and D.F.C. are probably two aspects of the NORs whose typical distribution, relative to the other nucleolar components, gives the interphasic nucleolus its characteristic morphology.     

Pseudo-Inductive Behaviour of the Membrane Potential of Chara corallina under Galvanostatic Conditions: A TIME-VARIANT CONDUCTANCE PROPERTY OF POTASSIUM CHANNELS

The membrane potential of Chara corallina Klein ex Willd, emR.D.W. displays an oscillatory behaviour in response to an appliedcurrent step. The relative amplitude and the frequency of oscillationof the overshoot increase with the strength of the current. Increasing temperature from 10 °C to 30 °C decreasesboth the relative overshoot amplitude and the static membraneresistance. The activation energy calculated from the Arrheniusplot of the frequency of the overshoot has a value of 36.1±2.3kJ mol_–1. Raising the external pH from 5.0 to 6.0 decreases the relativeamplitude of the overshoot and increases the steady state membraneresistance. Treating the cells for 30 s with 0.1 mol m_–3 N-ethylmaleimideinduces a rapid fall in both static membrane resistance andovershoot. These results are interpreted in terms of changes in potassiumchannels conductance. Key words: Chara corallina, Membrane potential, Potassium channels conductance