Nature 4.0: A networked sensor system for integrated biodiversity monitoring.

Ecosystem functions and services are severely threatened by unprecedented global loss in biodiversity. To counteract these trends, it is essential to develop systems to monitor changes in biodiversity for planning, evaluating, and implementing conservation and mitigation actions. However, the implementation of monitoring systems suffers from a trade-off between grain (i.e., the level of detail), extent (i.e., the number of study sites), and temporal repetition. Here, we present an applied and realized networked sensor system for integrated biodiversity monitoring in the Nature 4.0 project as a solution to these challenges, which considers plants and animals not only as targets of investigation, but also as parts of the modular sensor network by carrying sensors. Our networked sensor system consists of three main closely interlinked components with a modular structure: sensors, data transmission, and data storage, which are integrated into pipelines for automated biodiversity monitoring. We present our own real-world examples of applications, share our experiences in operating them, and provide our collected open data. Our flexible, low-cost, and open-source solutions can be applied for monitoring individual and multiple terrestrial plants and animals as well as their interactions. Ultimately, our system can also be applied to area-wide ecosystem mapping tasks, thereby providing an exemplary cost-efficient and powerful solution for biodiversity monitoring. Building upon our experiences in the Nature 4.0 project, we identified ten key challenges that need to be addressed to better understand and counteract the ongoing loss of biodiversity using networked sensor systems. To tackle these challenges, interdisciplinary collaboration, additional research, and practical solutions are necessary to enhance the capability and applicability of networked sensor systems for researchers and practitioners, ultimately further helping to ensure the sustainable management of ecosystems and the provision of ecosystem services.

Drift on holey landscapes as a dominant evolutionary process.

An organism's phenotype has been shaped by evolution but the specific processes have to be indirectly inferred for most species. For example, correlations among traits imply the historical action of correlated selection and, more generally, the expression and distribution of traits is expected to be reflective of the adaptive landscapes that have shaped a population. However, our expectations about how quantitative traits-like most behaviors, physiological processes, and life-history traits-should be distributed under different evolutionary processes are not clear. Here, we show that genetic variation in quantitative traits is not distributed as would be expected under dominant evolutionary models. Instead, we found that genetic variation in quantitative traits across six phyla and 60 species (including both Plantae and Animalia) is consistent with evolution across high-dimensional "holey landscapes." This suggests that the leading conceptualizations and modeling of the evolution of trait integration fail to capture how phenotypes are shaped and that traits are integrated in a manner contrary to predictions of dominant evolutionary theory. Our results demonstrate that our understanding of how evolution has shaped phenotypes remains incomplete and these results provide a starting point for reassessing the relevance of existing evolutionary models.

Implementing code review in the scientific workflow: Insights from ecology and evolutionary biology.

Code review increases reliability and improves reproducibility of research. As such, code review is an inevitable step in software development and is common in fields such as computer science. However, despite its importance, code review is noticeably lacking in ecology and evolutionary biology. This is problematic as it facilitates the propagation of coding errors and a reduction in reproducibility and reliability of published results. To address this, we provide a detailed commentary on how to effectively review code, how to set up your project to enable this form of review and detail its possible implementation at several stages throughout the research process. This guide serves as a primer for code review, and adoption of the principles and advice here will go a long way in promoting more open, reliable, and transparent ecology and evolutionary biology.

Fencing amplifies individual differences in movement with implications on survival for two migratory ungulates.

Fences have recently been recognized as one of the most prominent linear infrastructures on earth. As animals traverse fenced landscapes, they adjust movement behaviours to optimize resource access while minimizing energetic costs of coping with fences. Examining individual responses is key for connecting localized fence effects with population dynamics. We investigated the multi-scale effects of fencing on animal movements, space use and survival of 61 pronghorn and 96 mule deer on a gradient of fence density in Wyoming, USA. Taking advantage of the recently developed Barrier Behaviour Analysis, we classified individual movement responses upon encountering fences (i.e. barrier behaviours). We adopted the reaction norm framework to jointly quantify individual plasticity and behavioural types of barrier behaviours, as well as behaviour syndromes between barrier behaviours and animal space use. We also assessed whether barrier behaviours affect individual survival. Our results highlighted a high-level individual plasticity encompassing differences in the degree and direction of barrier behaviours for both pronghorn and mule deer. Additionally, these individual differences were greater at higher fence densities. For mule deer, fence density determined the correlation between barrier behaviours and space use and was negatively associated with individual survival. However, these relationships were not statistically significant for pronghorn. By integrating approaches from movement ecology and behavioural ecology with the emerging field of fence ecology, this study provides new evidence that an extraordinarily widespread linear infrastructure uniquely impacts animals at the individual level. Managing landscape for lower fence densities may help prevent irreversible behavioural shifts for wide-ranging animals in fenced landscapes.

Phylogenetic conservation of behavioural variation and behavioural syndromes.

Individuals frequently differ consistently from one another in their average behaviours (i.e. 'animal personality') and in correlated suites of consistent behavioural responses (i.e. 'behavioural syndromes'). However, understanding the evolutionary basis of this (co)variation has lagged behind demonstrations of its presence. This lag partially stems from comparative methods rarely being used in the field. Consequently, much of the research on animal personality has relied on 'adaptive stories' focused on single species and populations. Here, we used a comparative approach to examine the role of phylogeny in shaping patterns of average behaviours, behavioural variation and behavioural correlations. In comparing the behaviours and behavioural variation for five species of Gryllid crickets, we found that phylogeny shaped average behaviours and behavioural (co)variation. Despite differences among species, behavioural responses and variation were most similar among more closely related species. These results suggest that phylogenetic constraints play an important role in the expression of animal personalities and behavioural syndromes and emphasize the importance of examining evolutionary explanations within a comparative framework.

Biologging reveals individual variation in behavioural predictability in the wild.

Recent research highlights the ecological importance of individual variation in behavioural predictability. Individuals may not only differ in their average expression of a behavioural trait (their behavioural type) and in their ability to adjust behaviour to changing environmental conditions (individual plasticity), but also in their variability around their average behaviour (predictability). However, quantifying behavioural predictability in the wild has been challenging due to limitations of acquiring sufficient repeated behavioural measures. We here demonstrate how common biologging data can be used to detect individual variation in behavioural predictability in the wild and reveal the coexistence of highly predictable individuals along with unpredictable individuals within the same population. We repeatedly quantified two behaviours-daily movement distance and diurnal activity-in 62 female brown bears Ursus arctos tracked across 187 monitoring years. We calculated behavioural predictability over the short term (50 consecutive monitoring days within 1 year) and long term (across monitoring years) as the residual intra-individual variability (rIIV) of behaviour around the behavioural reaction norm. We tested whether predictability varies systematically across average behavioural types and whether it is correlated across functionally distinct behaviours, that is, daily movement distance and amount of diurnal activity. Brown bears showed individual variation in behavioural predictability from predictable to unpredictable individuals. For example, the standard deviation around the average daily movement distance within one monitoring year varied up to fivefold from 1.1 to 5.5 km across individuals. Individual predictability for both daily movement distance and diurnality was conserved across monitoring years. Individual predictability was correlated with behavioural type where individuals which were on average more diurnal and mobile were also more unpredictable in their behaviour. In contrast, more nocturnal individuals moved less and were more predictable in their behaviour. Finally, individual predictability in daily movement distance and diurnality was positively correlated, suggesting that individual predictability may be a quantitative trait in its own regard that could evolve and is underpinned by genetic variation. Unpredictable individuals may cope better with stochastic events and unpredictability may hence be an adaptive behavioural response to increased predation risk. Coexistence of predictable and unpredictable individuals may therefore ensure adaptable and resilient populations.

Behavioural syndromes shape evolutionary trajectories via conserved genetic architecture.

Behaviours are often correlated within broader syndromes, creating the potential for evolution in one behaviour to drive evolutionary changes in other behaviours. Despite demonstrations that behavioural syndromes are common, this potential for evolutionary effects has not been demonstrated. Here we show that populations of field crickets (Gryllus integer) exhibit a genetically conserved behavioural syndrome structure, despite differences in average behaviours. We found that the distribution of genetic variation and genetic covariance among behavioural traits was consistent with genes and cellular mechanisms underpinning behavioural syndromes rather than correlated selection. Moreover, divergence among populations' average behaviours was constrained by the genetically conserved behavioural syndrome. Our results demonstrate that a conserved genetic architecture linking behaviours has shaped the evolutionary trajectories of populations in disparate environments-illustrating an important way for behavioural syndromes to result in shared evolutionary fates.

The Heritability of Behavior: A Meta-analysis.

The contribution of genetic variation to phenotypes is a central factor in whether and how populations respond to selection. The most common approach to estimating these influences is via the calculation of heritabilities, which summarize the contribution of genetic variation to phenotypic variation. Heritabilities also indicate the relative effect of genetic variation on phenotypes versus that of environmental sources of variation. For labile traits like behavioral responses, life history traits, and physiological responses, estimation of heritabilities is important as these traits are strongly influenced by the environment. Thus, knowing whether or not genetic variation is present within populations is necessary to understand whether or not these populations can evolve in response to selection. Here we report the results of a meta-analysis summarizing what we currently know about the heritability of behavior. Using phylogenetically controlled methods we assessed the average heritability of behavior (0.235)-which is similar to that reported in previous analyses of physiological and life history traits-and examined differences among taxa, behavioral classifications, and other biologically relevant factors. We found that there was considerable variation among behaviors as to how heritable they were, with migratory behaviors being the most heritable. Interestingly, we found no effect of phylogeny on estimates of heritability. These results suggest, first, that behavior may not be particularly unique in the degree to which it is influenced by factors other than genetics and, second, that those factors influencing whether a behavioral trait will have low or high heritability require further consideration.

Phenotypic integration in an extended phenotype: among-individual variation in nest-building traits of the alfalfa leafcutting bee (Megachile rotundata).

Structures such as nests and burrows are an essential component of many organisms' life-cycle and require a complex sequence of behaviours. Because behaviours can vary consistently among individuals and be correlated with one another, we hypothesized that these structures would (1) show evidence of among-individual variation, (2) be organized into distinct functional modules and (3) show evidence of trade-offs among functional modules due to limits on energy budgets. We tested these hypotheses using the alfalfa leafcutting bee, Megachile rotundata, a solitary bee and important crop pollinator. Megachile rotundata constructs complex nests by gathering leaf materials to form a linear series of cells in pre-existing cavities. In this study, we examined variation in the following nest construction traits: reproduction (number of cells per nest and nest length), nest protection (cap length and number of leaves per cap), cell construction (cell size and number of leaves per cell) and cell provisioning (cell mass) from 60 nests. We found a general decline in investment in cell construction and provisioning with each new cell built. In addition, we found evidence for both repeatability and plasticity in cell provisioning with little evidence for trade-offs among traits. Instead, most traits were positively, albeit weakly, correlated (r ~ 0.15), and traits were loosely organized into covarying modules. Our results show that individual differences in nest construction are detectable at a level similar to that of other behavioural traits and that these traits are only weakly integrated. This suggests that nest components are capable of independent evolutionary trajectories.

Genetic conservation and management of the California endemic, Torrey pine (Pinus torreyana Parry): Implications of genetic rescue in a genetically depauperate species.

Rare species present a challenge under changing environmental conditions as the genetic consequences of rarity may limit species ability to adapt to environmental change. To evaluate the evolutionary potential of a rare species, we assessed variation in traits important to plant fitness using multigenerational common garden experiments. Torrey pine, Pinus torreyana Parry, is one of the rarest pines in the world, restricted to one mainland and one island population. Morphological differentiation between island and mainland populations suggests adaptation to local environments may have contributed to trait variation. The distribution of phenotypic variances within the common garden suggests distinct population-specific growth trajectories underlay genetic differences, with the island population exhibiting substantially reduced genetic variance for growth relative to the mainland population. Furthermore, F1 hybrids, representing a cross between mainland and island trees, exhibit increased height accumulation and fecundity relative to mainland and island parents. This may indicate genetic rescue via intraspecific hybridization could provide the necessary genetic variation to persist in environments modified as a result of climate change. Long-term common garden experiments, such as these, provide invaluable resources to assess the distribution of genetic variance that may inform conservation strategies to preserve evolutionary potential of rare species, including genetic rescue.

Varying predator personalities generates contrasting prey communities in an agroecosystem.

Most taxa show consistent individual differences in behavior, a phenomenon often referred to as animal "personalities." While the links between individual personality and fitness have received considerable attention, little information is available on how animal personality impacts higher-order ecological processes, such as community dynamics. Using a mesocosm experiment, we subjected a representative community of alfalfa pests to different compositions of personality types of the wolf spider Pardosa milvina. We show that subtle variation in the personality composition of P. milvina populations generate wildly different prey communities, where a mixture of both active and sedentary individuals performs best at suppressing prey abundance. Our results provide the first experimental evidence that predator personality types can generate contrasting prey communities. Moreover, our results suggest that manipulating the representation of predator personality types may be a profitable avenue by which one can maximize the biocontrol potential of predator populations.