The Effects of Climate Seasonality on Behavior and Sleeping Site Choice in Sahamalaza Sportive Lemurs, <Emphasis Type="Italic">Lepilemur sahamalaza</Emphasis>

Temperature, rainfall, and resource availability may vary greatly within a single year in primate habitats. Many primate species show behavioral and physiological adaptations to this environmental seasonality, including changes to their diets and activity. Sahamalaza sportive lemurs (Lepilemur sahamalaza) inhabit the northwest of Madagascar and have been studied only during the dry, colder period of the year. We investigated potential effects of climate seasonality on this species by collecting behavioral data between October 2015 and August 2016, encompassing both the warmer wet and the colder dry seasons. We collected 773.15 hours of behavioral data on 14 individual sportive lemurs to investigate year-round activity budgets, ranging behavior, and sleeping site locations. Additionally we recorded temperature and rainfall data at our study site to describe the environmental conditions during the study period. The study individuals significantly decreased their time spent traveling and increased their time spent resting in the dry season compared to the wet season. Although home range size and path lengths did not differ over the study period, sleeping locations were significantly different between seasons as the lemurs focused on more confined areas in colder periods. Overall, the results indicate that Sahamalaza sportive lemur behavior varies with season, in line with reports for other primates.     

High Repeatability of Anti-Predator Responses and Resting Metabolic Rate in a Beetle

Measures of repeatability are essential for understanding behavioral consistency and individual differences in behavior, i.e. animal personalities. We studied anti-predator responses of the yellow mealworm beetle (Tenebrio molitor) and performed behavioral tests in plastic containers representing a typical laboratory environment of T. molitor. Behavioral tests were repeated in Eppendorf test tubes where we also measured resting metabolic rate (RMR). Results show that the response latency to a threatening/startling stimulus, and the total time spent in the state of tonic immobility, correlated across the tests. The behavioral responses were repeatable and RMR covaried phenotypically with personality: we found a negative correlation between response latency time and time spent immobile, a positive correlation between response latency and RMR, and a negative correlation between RMR and total time spent immobile. These correlations were also similar across trials performed in the Eppendorf test tubes and the plastic containers.     

Predation selects for low resting metabolic rate and consistent individual differences in anti-predator behavior in a beetle

Significant between-individual variation in resting metabolic rate (RMR) of animals is a widespread phenomenon that may have important implications for our understanding of variation in behavior and animal personality. By using wild caught mealworm beetles, Tenebrio molitor, we examined the relationships among survival rate under predator tests, individual response latency time to become immobile under the risk of predation, duration of immobility time, and RMR. Individuals with higher levels of RMR were bold, and bold individuals were found to be more exposed to the risk of bird predation. We found that RMR was positively correlated with the latency of immobility response and negatively correlated with the total duration of immobility. The correlation between behavioral responses suggests a behavioral syndrome in the anti-predator behavior of T. molitor. The results indicate that energy metabolism may be part of a syndrome that involves behavior and life history traits in animals.     

Group composition influences on behavioral sequence patterns of the Guiana dolphin Sotalia guianensis

Analysis of behavioral sequences displayed by different individuals can be used to infer individual decisions under diverse conditions. This study investigates whether behavioral transitions and routines differ according to the group composition of Guiana dolphins (Sotalia guianensis). We used the Z-score binomial test to detect significant behavioral transitions from a first-order transition matrix. The directed tree method was used to identify behavioral routines. Solitary individuals presented fewer transitions than heterogeneous groups. More routines were observed for heterogeneous than for homogeneous groups, and fewer routines for solitary individuals. Homogeneous groups maximized routines ending in traveling and milling, while heterogeneous groups presented higher probabilities of socializing. The analyses indicate that subgroups formed during Guiana dolphin fission–fusion events differed in probability of behavioral sequences, reflecting different feeding, resting, and socializing needs at different moments.     

From Aggregation to Dispersion: How Habitat Fragmentation Prevents the Emergence of Consensual Decision Making in a Group

In fragmented landscape, individuals have to cope with the fragmentation level in order to aggregate in the same patch and take advantage of group-living. Aggregation results from responses to environmental heterogeneities and/or positive influence of the presence of congeners. In this context, the fragmentation of resting sites highlights how individuals make a compromise between two individual preferences: (1) being aggregated with conspecifics and (2) having access to these resting sites. As in previous studies, when the carrying capacity of available resting sites is large enough to contain the entire group, a single aggregation site is collectively selected. In this study, we have uncoupled fragmentation and habitat loss: the population size and total surface of the resting sites are maintained at a constant value, an increase in fragmentation implies a decrease in the carrying capacity of each shelter. For our model organism, Blattella germanica, our experimental and theoretical approach shows that, for low fragmentation level, a single resting site is collectively selected. However, for higher level of fragmentation, individuals are randomly distributed between fragments and the total sheltered population decreases. In the latter case, social amplification process is not activated and consequently, consensual decision making cannot emerge and the distribution of individuals among sites is only driven by their individual propensity to find a site. This intimate relation between aggregation pattern and landscape patchiness described in our theoretical model is generic for several gregarious species. We expect that any group-living species showing the same structure of interactions should present the same type of dispersion-aggregation response to fragmentation regardless of their level of social complexity.     

Are shy individuals less behaviorally variable? Insights from a captive population of mouse lemurs

Increasingly, individual variation in personality has become a focus of behavioral research in animal systems. Boldness and shyness, often quantified as the tendency to explore novel situations, are seen as personality traits important to the fitness landscape of individuals. Here we tested for individual differences within and across contexts in behavioral responses of captive mouse lemurs (Microcebus murinus) to novel objects, novel foods, and handling. We report consistent differences in behavioral responses for objects and handling. We also found that the responses to handling and novel objects were correlated and repeatable. Lastly, we show that shyer individuals may show less variability in their behavioral responses. This study provides new information on the potential for behavioral syndromes in this species and highlights differences in the degree to which behavioral types (e.g., shy/bold) vary in their behavioral responses.     

Reactions to Media Violence: It’s in the Brain of the Beholder

Media portraying violence is part of daily exposures. The extent to which violent media exposure impacts brain and behavior has been debated. Yet there is not enough experimental data to inform this debate. We hypothesize that reaction to violent media is critically dependent on personality/trait differences between viewers, where those with the propensity for physical assault will respond to the media differently than controls. The source of the variability, we further hypothesize, is reflected in autonomic response and brain functioning that differentiate those with aggression tendencies from others. To test this hypothesis we pre-selected a group of aggressive individuals and non-aggressive controls from the normal healthy population; we documented brain, blood-pressure, and behavioral responses during resting baseline and while the groups were watching media violence and emotional media that did not portray violence. Positron Emission Tomography was used with [¹⁸F]fluoro-deoxyglucose (FDG) to image brain metabolic activity, a marker of brain function, during rest and during film viewing while blood-pressure and mood ratings were intermittently collected. Results pointed to robust resting baseline differences between groups. Aggressive individuals had lower relative glucose metabolism in the medial orbitofrontal cortex correlating with poor self-control and greater glucose metabolism in other regions of the default-mode network (DMN) where precuneus correlated with negative emotionality. These brain results were similar while watching the violent media, during which aggressive viewers reported being more Inspired and Determined and less Upset and Nervous, and also showed a progressive decline in systolic blood-pressure compared to controls. Furthermore, the blood-pressure and brain activation in orbitofrontal cortex and precuneus were differentially coupled between the groups. These results demonstrate that individual differences in trait aggression strongly couple with brain, behavioral, and autonomic reactivity to media violence which should factor into debates about the impact of media violence on the public.     

Effect of meiofauna on macrofauna recruitment: settlement inhibition of the polychaete Hydroides elegans by the harpacticoid copepod Tisbe japonica

Various aspects of marine macroinvertebrate ecology cannot be understood without detailed knowledge of larval settlement processes. An important effect underscored during the settlement process is the disturbance of marine invertebrate larvae by predators. We demonstrated that biotic disturbance, comprising physical elimination and mortality due to predation and the behavioral irritation of larvae by the harpacticoid copepod Tisbe japonica, prevent a significant portion of larvae of the polychaete Hydroides elegans from settlement on otherwise suitable substrata. Experiments were performed both in the laboratory and the field showing reproducible significant differences in larval settlement and mortality rates between gender-specific copepod treatments and the control. The trend of decreased larval settlement in the presence of copepods coincided with increased larval mortality in these treatments. In the corresponding field experiments, larval settlement and mortality were similar to the ones obtained under laboratory conditions.     

Behavioral adjustments and support use of François' langur in limestone habitat in Fusui,China: Implications for behavioral thermoregulation

Climatic factors such as temperature and humidity vary seasonally in primate habitats; thus, behavioral adjustments and microhabitat selection by primate species have been interpreted as behavioral adaptations. François' langur (Trachypithecus francoisi), a native species to southwest China and northern Vietnam, inhabits a limestone habitat with extreme climatic conditions. To understand the potential effects of climatic seasonality on this species, we collected data on the individual behavioral budgets in a T. francoisi group between January and December 2010 in Fusui County, China. Monthly, we performed 5–11 days of observation during this period, using focal animal sampling and continuous recording methods. We also recorded ambient temperature (T_a) and relative humidity (H_r) data at our study site. Results indicated that T_a and H_r were significantly correlated with each other and fluctuated dramatically on a daily, monthly, and seasonal basis. The amount of time spent resting, grooming, basking, and huddling also varied on a daily, monthly, and seasonal basis. The proportion of resting time and total sedentary activity time significantly increased at high and low T_as, respectively. The total sedentary time, resting time, and plant branch use all showed positive significant correlations with T_a. Our results suggest that behavioral adjustment and support use of T. francoisi, at least partly, were related to thermoregulation. T. francoisi minimized thermal stress through behavioral adjustments and support use. It is an adaptive behavior associated with the climatic extremes of limestone habitat. This study can potentially advise conservation management strategies in this specific habitat. Conservation efforts should focus on vegetation restoration in langurs' habitat, including those in the foothills.     

Interspecific interactions between wild black and gold howlermonkeys (<Emphasis Type="Italic">Alouatta caraya</Emphasis>) and other mammals in northeastern Argentina

We studied the interactions between wild black and gold howler monkeys (Alouatta caraya) and other mammals at three sites with different human disturbance levels and forest structures in northeastern Argentina. The main goal was to evaluate the effects of the study site and type of interaction (agonistic or non-agonistic) on the rate of interaction. In addition, we also described the associations between interspecific interaction rate, species involved, howler monkeys’ activity, and seasonality. We present 50 group-years for 14 groups, collected between 2003 and 2012. We registered a total of 29 interactions (0.22 ± 0.26 interactions/100 h). Most interactions (56.7%) were agonistic (12% of high intensity and 88% of low intensity), 41.9% were neutral, and 1.5% were affiliative. We found that both factors, site and type of interaction, have an effect on the rate of interaction. Interspecific interactions were more frequent at the two sites without human settlement than in the rural site. Interspecific interactions occurred during resting (46.73%), traveling (27.40%), and feeding (25.87%). Interactions occurred throughout the year but were concentrated in August (late winter) and September (beginning of spring). Our results suggest that both site and type of interaction affected the rate of interaction between howler monkeys and other mammals in northeastern Argentina. Agonistic interactions were more frequent that non-agonistic ones, and monkeys reacted agonistically to several mammalian species, but these interactions were mainly of low intensity.     

Maladaptive behavior reinforces a recruitment bottleneck in newly settled fishes

Settlement from the plankton ends the major dispersive stage of life for many marine organisms and exposes them to intense predation pressure in juvenile habitats. This predation mortality represents a life-history bottleneck that can determine recruitment success. At the level of individual predator–prey interactions, prey survival depends upon behavior, specifically how behavior affects prey conspicuousness and evasive ability. We conducted an experiment to identify behavioral traits and performance levels that are important determinants of which individuals survive or die soon after settlement. We measured a suite of behavioral traits on late stage, pre-settlement Ward's damsel (Pomacentrus wardi) collected using light traps. These behavioral traits included two measures of routine swimming (indicators of conspicuousness) and eight measures of escape performance to a visual startle stimulus. Fish were then released onto individual patch reefs, where divers measured an additional behavioral trait (boldness). We censused each patch reef until approximately 50% of the fish were missing (~24 h), which we assumed to be a result of predation. We used classification tree analysis to discriminate survivors from fish presumed dead based on poor behavioral performance. The classification tree revealed that individuals displaying the maladaptive combination of low escape response speed, low boldness on the reef, and high routine swimming speed were highly susceptible to predation (92.4% with this combination died within 24 h). This accounted for 55.2% of all fish that died. Several combinations of behavioral traits predicted likely survival over 24 h, but there was greater uncertainty about that prediction than there was for fish that were predicted to die. Thus maladaptive behavioral traits were easier to identify than adaptive traits.     

Behavioral and Physiological Changes during Benthic-Pelagic Transition in the Harmful Alga,Heterosigma akashiwo: Potential for Rapid Bloom Formation

Many species of harmful algae transition between a motile, vegetative stage in the water column and a non-motile, resting stage in the sediments. Physiological and behavioral traits expressed during benthic-pelagic transition potentially regulate the timing, location and persistence of blooms. The roles of key physiological and behavioral traits involved in resting cell emergence and bloom formation were examined in two geographically distinct strains of the harmful alga, Heterosigma akashiwo. Physiological measures of cell viability, division and population growth, and cell fatty acid content were made using flow cytometry and gas chromatography – mass spectrometry techniques as cells transitioned between the benthic resting stage and the vegetative pelagic stage. Video-based tracking was used to quantify cell-level swimming behaviors. Data show increased temperature and light triggered rapid emergence from the resting stage and initiated cell swimming. Algal strains varied in important physiological and behavioral traits, including survivorship during life-stage transitions, population growth rates and swimming velocities. Collectively, these traits function as “population growth strategies” that can influence bloom formation. Many resting cells regained the up-swimming capacity necessary to cross an environmentally relevant halocline and the ability to aggregate in near-surface waters within hours after vegetative growth supporting conditions were restored. Using a heuristic model, we illustrate how strain-specific population growth strategies can govern the timescales over which H. akashiwo blooms form. Our findings highlight the need for identification and quantification of strain-specific physiological and behavioral traits to improve mechanistic understanding of bloom formation and successful bloom prediction.     

Time matters. Locomotor behavior of <Emphasis Type="Italic">Lacerta viridis</Emphasis> and <Emphasis Type="Italic">Lacerta agilis</Emphasis> in an open field maze

Locomotor performance provides one of the key pieces of information regarding whole-organism function. Experiments encompassing behavioral data commonly endeavor to measure parameters such as burst speed, latency time, distance traveled, and other aspects of locomotion. Behavioral experiments can uncover an immense range of information, from the individual, interspecific, and intraspecific levels up to correlations with ecological factors and parameters from the ecosystem. Here, we explored the locomotor behavior of two lizard species, Lacerta viridis and Lacerta agilis, in an open field test (OFT). The main aim was to reveal changes in locomotion over time. Although we observed no time-related variation in L. agilis, we discovered significant changes in locomotor behavior over the course of the experiment in Lacerta viridis. Measured behavioral traits (resting time, total distance traveled, mean speed) showed significant changes across time in L. viridis, thus indicating the importance of time as a factor when conducting behavioral experiments. Moreover, we observed that in 10-min experimental session, the individuals have undergone different stages from freezing behavior, exploration, to habituation.     

Adaptive settlement in sedge warblers Acrocephalus schoenobaenus—focus on the scale of individuals

Breeding site selection can be linked to population dynamics through pre-emptive site selection, by which an individual selects the best (in terms of fitness) available site, preventing others from sharing it. We examined the pattern of territorial settlement and its fitness consequences during a study of sedge warblers Acrocephalus schoenobaenus inhabiting two study plots in the Nida Wetlands (southern Poland). Throughout all 7 years of the study (1997–2003), male sedge warblers repeatedly occupied sites in sequence from best to worst, according to the amount of cover by reedmace and common reed on one plot, and the amount of common reed on the other plot. As individuals aged, they occupied sites with increasingly higher proportions of reedmace and common reed. On the first plot, where the within-habitat heterogeneity was greater, settlement date and consequently reedmace and common reed cover at the sites occupied by a male had a positive influence on that male's fitness components: the probability of mating, nesting success, and the number of offspring recruited to the breeding population in succeeding years. On the second plot, which was more homogenous, there was no such evident relationship between fitness and the proportion of cover by reeds.     

The Use of an Invasive Species Habitat by a Small Folivorous Primate: Implications for Lemur Conservation in Madagascar

The lemurs of Madagascar are among the most threatened mammalian taxa in the world, with habitat loss due to shifting cultivation and timber harvest heavily contributing to their precarious state. Deforestation often leads to fragmentation, resulting in mixed-habitat matrices throughout a landscape where disturbed areas are prone to invasion by exotic plants. Our study site, the Mandena littoral forest (southeast Madagascar), is a matrix of littoral forest, littoral swamp, and Melaleuca swamp habitats. Here, Melaleuca quinquenervia has invaded the wetland ecosystem, creating a mono-dominant habitat that currently provides the only potential habitat corridor between forest fragments. We sought to understand the role of this invasive Melaleuca swamp on the behavioral ecology of a threatened, small-bodied folivore, the southern bamboo lemur (Hapalemur meridionalis). We collected botanical and behavioral data on four groups of H. meridionalis between January and December 2013. Our results confirm Melaleuca swamp as an important part of their home range: while lemurs seasonally limited activities to certain habitats, all groups were capable of utilizing this invasive habitat for feeding and resting. Furthermore, the fact that Hapalemur use an invasive plant species as a dispersal corridor increases our knowledge of their ecological flexibility, and may be useful in the conservation management of remaining threatened populations.     

Repeatable nest defense behavior in a wild population of Eastern bluebirds (Sialia sialis) as evidence of personality

Consistent individual differences in behavior, or personality, have been demonstrated in a variety of species other than humans, including mammals, birds, and invertebrates. Behavioral consistency has been shown to affect dispersal, foraging, exploration, and antipredator responses, which may have an impact on parental and offspring survival. Despite increasing research in behavioral consistency, the repeatability of nest defense behavior has rarely been assessed in wild bird populations. Furthermore, previous studies investigating nest defense behavior have utilized laboratory studies or mounted predators to elicit defensive behavior. It is important to assess personality in wild populations to fully understand the fitness consequences of behavioral consistency across natural contexts and to utilize live predators or competitors for accurate assessment of defensive behavior. We used an ecologically relevant, live, invasive, nest site competitor, the house sparrow (Passer domesticus), to elicit nest defense behavior in a wild population of Eastern bluebirds (Sialia sialis) to determine if nest defense behavior is repeatable within and between years for males and females (males: 2009, N?=?17; 2010, N?=?18; both years, N?=?9. Females: 2009, N?=?22; 2010, N?=?15; both years, N?=?11). We also determined if individual behavior changes as a function of season, parental age, brood size, or the number of house sparrows around the nest site. We found that females demonstrated repeatable behavior both within and between years. Male nest defense behavior was only repeatable in 1 year and was influenced by season in the other year. Parental age, brood size, and the number of house sparrows around the nest site did not affect nest defense behavior. We conclude that Eastern bluebirds demonstrate consistent nest defense behavior, or personality, although males are more plastic than females.     

Site fidelity and behavioral plasticity regulate an ungulate’s response to extreme disturbance

With rapid global change, the frequency and severity of extreme disturbance events are increasing worldwide. The ability of animal populations to survive these stochastic events depends on how individual animals respond to their altered environments, yet our understanding of the immediate and short‐term behavioral responses of animals to acute disturbances remains poor. We focused on animal behavioral responses to the environmental disturbance created by megafire. Specifically, we explored the effects of the 2018 Mendocino Complex Fire in northern California, USA, on the behavior and body condition of black‐tailed deer (Odocoileus hemionus columbianus). We predicted that deer would be displaced by the disturbance or experience high mortality post‐fire if they stayed in the burn area. We used data from GPS collars on 18 individual deer to quantify patterns of home range use, movement, and habitat selection before and after the fire. We assessed changes in body condition using images from a camera trap grid. The fire burned through half of the study area, facilitating a comparison between deer in burned and unburned areas. Despite a dramatic reduction in vegetation in burned areas, deer showed high site fidelity to pre‐fire home ranges, returning within hours of the fire. However, mean home range size doubled after the fire and corresponded to increased daily activity in a severely resource‐depleted environment. Within their home ranges, deer also selected strongly for patches of surviving vegetation and woodland habitat, as these areas provided forage and cover in an otherwise desolate landscape. Deer body condition significantly decreased after the fire, likely as a result of a reduction in forage within their home ranges, but all collared deer survived for the duration of the study. Understanding the ways in which large mammals respond to disturbances such as wildfire is increasingly important as the extent and severity of such events increases across the world. While many animals are adapted to disturbance regimes, species that exhibit high site fidelity or otherwise fixed behavioral strategies may struggle to cope with increased climate instability and associated extreme disturbance events.     

Of mice and men--universality and breakdown of behavioral organization

Mental or cognitive brain functions, and the effect on them of abnormal psychiatric diseases, are difficult to approach through molecular biological techniques due to the lack of appropriate assay systems with objective measures. We therefore study laws of behavioral organization, specifically how resting and active periods are interwoven throughout daily life, using objective criteria, and first discover that identical laws hold both for healthy humans subject to the full complexity of daily life, and wild-type mice subject to maximum environmental constraints. We find that active period durations with physical activity counts successively above a predefined threshold, when rescaled with individual means, follow a universal stretched exponential (gamma-type) cumulative distribution, while resting period durations below the threshold obey a universal power-law cumulative distribution with identical parameter values for both of the mammalian species. Further, by analyzing the behavioral organization of mice with a circadian clock gene (Period2) eliminated, and humans suffering from major depressive disorders, we find significantly lower parameter values (power-law scaling exponents) for the resting period durations in both these cases. Such a universality and breakdown of the behavioral organization of mice and humans, revealed through objective measures, is expected to facilitate the understanding of the molecular basis of the pathophysiology of neurobehavioral diseases, including depression, and lay the foundations for formulating a range of neuropsychiatric behavioral disorder models.     

First dendro-archaeological evidence of a completely excavated medieval settlement in the extreme north of Western Siberia

The Buchta Nakhodka settlement is the only archaeological site in the northern part of Western Siberia that has been fully excavated. This well-preserved settlement on Russia’s Yamal Peninsula around 67° N and 72° E, however, has not yet been calendar dated, and the cultural identity of its inhabitants still remains unknown. Here we apply, for the first time, dendrochronological techniques to absolutely date 13 of the most important archaeological timbers from the Buchta Nakhodka settlement. Statistical robust cross-dating results place the construction into the second quarter of the 13th century. The Buchta Nakhodka settlement reveals no obvious connection with the modern, nomadic population of Yamal, the Nenets. Together with a careful literature review, this study indicates that the closest construction techniques and subsequent settlement forms can be found on Iceland and across northern Fennoscandia, where Sami people are building their houses in a similar way. Our combined archaeological, dendrochronological, ethnographical and (archaeo)zoological evidence suggests that the ancient inhabitants of Buchta Nakhodka were closely related to the Sihirtya people that were often mentioned in ancient Nenets folklore as legendary people who inhabited the Yamal Peninsula previously. In providing unique insights into the medieval settlement history of the northern part of Western Siberia, we hope to encourage further interdisciplinary research projects to be launched at Eurasia’s high-northern latitudes.     

Testing the relationship between intraspecific competition and individual specialization across both behavior and diet

Individual specialization within populations is increasingly recognized as important in both ecology and evolution, but researchers working on intraspecific variation in behavior and diet infrequently interact. This may be because individual specialization on diet and behavior was historically difficult to investigate simultaneously on the same individuals. However, approaches like stable isotope analysis that allow hindcasting past field diets for laboratory organisms may provide opportunities to unite these areas of inquiry. Here, we tested the role of intraspecific competition on individual specialization through analysis of both behavior and diet simultaneously. We focused on intraspecific competition as a mechanism that might drive individual specialization of both diet and behavior. We conducted this study in Vilas County, Wisconsin, United States (US), using rusty crayfish Faxonius rusticus from six lakes across a relative abundance gradient. We conducted six assays to measure individual specialization of behavior and used stable isotope analysis to measure individual specialization of diet. We then related both measures of individual specialization to relative abundance of F. rusticus using linear and quadratic models. We found a unimodal relationship between intraspecific competition and individual specialization of diet for F. rusticus, likely because some preferred resources are unavailable to specialize on at the highest densities of this well‐studied crayfish invader. Conversely, we found greater support for a linear relationship between individual specialization of behavior and intraspecific competition, perhaps because specialization by behavior is not inherently resource‐limited. Our results show that dietary and behavioral specialization may exhibit different responses to increased intraspecific competition, and demonstrate a potential technique that can be used to investigate individual specialization of diet and behavior simultaneously for the same individuals and populations.