Full-length RNA transcript sequencing traces brain isoform diversity in house mouse natural populations.

The ability to generate multiple RNA transcript isoforms from the same gene is a general phenomenon in eukaryotes. However, the complexity and diversity of alternative isoforms in natural populations remain largely unexplored. Using a newly developed full-length transcript enrichment protocol with 5' CAP selection, we sequenced full-length RNA transcripts of 48 individuals from outbred populations and subspecies of , and from the closely related sister species and as outgroups.

Is the speed of adjusting to environmental change condition dependent? An experiment with house mice ().

Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and time. Often, a change in behavior is the first response to changing conditions. Behavioral flexibility can potentially improve an organism's chances to survive and reproduce.

Food quality influences behavioural flexibility and cognition in wild house mice.

Environmental change is frequent. To adjust and survive, animals need behavioural flexibility. Recently, cognitive flexibility has emerged as a driving force for adjusting to environmental change.

Shifts in energy allocation and reproduction in response to temperature in a small precocial mammal.

Background: Species adjust to changes in temperature and the accompanying reduction in resource availability during the annual cycle by shifts in energy allocation. As it gets colder, the priority of energy allocation to maintenance increases and reproduction is reduced or abandoned.

Results: We studied whether and how young female guinea pigs (Cavia porcellus) adjust even under ad libitum food conditions growth, storage of fat reserves and reproduction when kept at 5 °C versus 15 °C, and how offspring born into these conditions compensate during development to independence.

Stressfulness of the design influences consistency of cognitive measures and their correlation with animal personality traits in wild mice (Mus musculus).

Individual variation in cognition is being increasingly recognized as an important evolutionary force but contradictory results so far hamper a general understanding of consistency and association with other behaviors. Partly, this might be caused by external factors imposed by the design. Stress, for example, is known to influence cognition, with mild stress improving learning abilities, while strong or chronic stress impairs them.

Fast adjustment of pace-of-life and risk-taking to changes in food quality by altered gene expression in house mice.

The pace-of-life syndrome hypothesis provides a framework for the adaptive integration of behaviour, physiology and life history between and within species. It suggests that behaviours involving a risk of death or injury should co-vary with a higher allocation to fast reproduction. Empirical support for this hypothesis is mixed, presumably because important influencing factors such as environmental variation, are usually neglected.

Lifetime Observation of Cognition and Physiological Parameters in Male Mice.

Laboratory mice are predominantly used for one experiment only, i.e., new mice are ordered or bred for every new experiment.

Enhanced problem-solving ability as an adaptation to urban environments in house mice.

Humans have a large impact on the distribution and abundance of animal species worldwide. The ecological effects of human-altered environments are being increasingly recognized and understood, but their effects on evolution are largely unknown. Enhanced cognitive abilities and the ability to innovate have been suggested as crucial traits for thriving in human-altered habitats.

Zebra finches bi-directionally selected for personality differ in repeatability of corticosterone and testosterone.

Consistent between-individual differences in behaviour have been documented across the animal kingdom. Such variation between individuals has been shown to be the basis for selection and to act as a pacemaker for evolutionary change. Recently, equivocal evidence suggests that such consistent between-individual variation is also present in hormones.

Reproduction affects immune defenses in the guinea pig even under ad libitum food.

Reproduction is one of the costliest processes in the life of an animal. Life history theory assumes that when resources are limiting allocation to reproduction will reduce allocation to other essential processes thereby inducing costs of reproduction. The immune system is vital for survival.

Within-Family Environment and Cross-Fostering Stress Affect Behavior and Physiology in Wild Cavies ().

Stability of personality traits is well-documented for a wide variety of animals. However, previous results also suggest that behavioral phenotypes are plastic during early ontogeny and can be adaptively shaped to the social environment. In cavies (), it has already been documented that the size at birth relative to siblings (size rank) greatly influences various behavioral and physiological traits that last at least until independence.

Senescence and costs of reproduction in the life history of a small precocial species.

Species following a fast life history are expected to express fitness costs mainly as increased mortality, while slow-lived species should suffer fertility costs. Because observational studies have limited power to disentangle intrinsic and extrinsic factors influencing senescence, we manipulated reproductive effort experimentally in the cavy ( which produces extremely precocial young. We created two experimental groups: One was allowed continuous reproduction (CR) and the other intermittent reproduction (IR) by removing males at regular intervals.

Does Animal Personality Affect Movement in Habitat Corridors? Experiments with Common Voles () using Different Corridor Widths.

Animal personality may affect an animal's mobility in a given landscape, influencing its propensity to take risks in an unknown environment. We investigated the mobility of translocated common voles in two corridor systems 60 m in length and differing in width (1 m and 3 m). Voles were behaviorally phenotyped in repeated open field and barrier tests.

Future Directions for Personality Research: Contributing New Insights to the Understanding of Animal Behavior.

As part of the European Conference on Behavioral Biology 2018, we organized a symposium entitled, "" The aims of this symposium were to address current research in the personality field, spanning both behavioral ecology and psychology, to highlight the future directions for this research, and to consider whether differential approaches to studying behavior contribute something new to the understanding of animal behavior. In this paper, we discuss the study of endocrinology and ontogeny in understanding how behavioral variation is generated and maintained, despite selection pressures assumed to reduce this variation. We consider the potential mechanisms that could link certain traits to fitness outcomes through longevity and cognition.

An Autaptic Culture System for Standardized Analyses of iPSC-Derived Human Neurons.

iPSC-derived human neurons are expected to revolutionize studies on brain diseases, but their functional heterogeneity still poses a problem. Key sources of heterogeneity are the different cell culture systems used. We show that an optimized autaptic culture system, with single neurons on astrocyte feeder islands, is well suited to culture, and we analyze human iPSC-derived neurons in a standardized, systematic, and reproducible manner.

Sex differences in life history, behavior, and physiology along a slow-fast continuum: a meta-analysis.

The pace-of-life syndrome (POLS) hypothesis predicts that behavior and physiology covary with life history. Evidence for such covariation is contradictory, possibly because systematic sources of variation (e.g.

Life-history trade-offs: are they linked to personality in a precocial mammal ()?

Life-history trade-offs are predicted to contribute to the maintenance of personality variation. Individuals with 'fast' lifestyles should develop faster, reproduce earlier and exhibit more risky behaviours. Evidence for such predicted links, however, remains equivocal.

Effect of season on reproductive behaviors and fertilization success in cavies (Cavia aperea).

Finding the optimal timing for breeding is crucial for small mammals to ensure survival and maximize lifetime reproductive success. Species living in temperate regions therefore often restrict breeding to seasons with favorable food and weather conditions. Although caviomorph rodents such as guinea pigs are described as non-seasonal breeders, a series of recent publications has shown seasonal adaptations in litter size, offspring birth mass and maternal investment.

Stability of the guinea pigs personality - cognition - linkage over time.

In human psychological research, personality traits as well as cognitive traits are usually validated for both, their stability over time and contexts. While stability over time gives an estimate on how genetically fixated a trait can be, correlations across traits have the power to reveal linkages or trade - offs. In animals, these validations have widely been done for personality but not for cognitive traits.

Blastocyst recovery and multifactorial gene expression analysis in the wild guinea pig (Cavia aperea).

The expression of specific developmentally important genes in preimplantation embryos is an accepted marker for unraveling the influence of single factors in studies that are mostly related to artificial reproduction techniques. Such studies, however, often reveal high levels of heterogeneity between single embryos, independently of the influence of factors of interest. A possible explanation for this variation could be the large variety of physiological and environmental factors to which early embryos are exposed and their ability to react to them.

The maternal social environment shapes offspring growth, physiology, and behavioural phenotype in guinea pigs.

Background: Prenatal conditions influence offspring development in many species. In mammals, the effects of social density have traditionally been considered a detrimental form of maternal stress. Now their potential adaptive significance is receiving greater attention.

Domestication effects on behavioural traits and learning performance: comparing wild cavies to guinea pigs.

The domestication process leads to a change in behavioural traits, usually towards individuals that are less attentive to changes in their environment and less aggressive. Empirical evidence for a difference in cognitive performance, however, is scarce. Recently, a functional linkage between an individual's behaviour and cognitive performance has been proposed in the framework of animal personalities via a shared risk-reward trade-off.

Animal housing and welfare: effects of housing conditions on body weight and cortisol in a medium-sized rodent (Cavia aperea).

Rodents are the most abundant experimental nonhuman animals and are commonly studied under standard laboratory housing conditions. As housing conditions affect animals' physiology and behavior, this study investigated the effects of indoor and outdoor housing conditions on body weight and cortisol level of wild cavies, Cavia aperea. The changing housing condition strongly influenced both parameters, which are commonly used as indicators for animal welfare.

Learning and personality types are related in cavies (Cavia aperea).

The evolution and maintenance of consistent individual differences, so called animal personalities, have attracted much research interest over the past decades. Variation along common personality traits, such as boldness or exploration, is often associated with risk-reward trade-offs. Individuals that are bolder and hence take more risks may be more successful in acquiring resources over the short term.