Jens Krause

Jens Krause
Humboldt-Universität zu Berlin | HU Berlin

About

285
Publications
103,637
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
24,798
Citations

Publications

Publications (285)
Article
The increasing miniaturisation of animal-tracking technology has made it possible to gather exceptionally detailed machine-sensed data on the social dynamics of almost entire populations of individuals, in both terrestrial and aquatic study systems. Here, we review important issues concerning the collection of such data, and their processing and an...
Article
Full-text available
The study of social identity and crowd psychology looks at how and why individual people change their behaviour in response to others. Within a group, a new behaviour can emerge first in a few individuals before it spreads rapidly to all other members. A number of mathematical models have been hypothesized to describe these social contagion phenome...
Article
Full-text available
In a wide range of contexts, including predator avoidance, medical decision-making and security screening, decision accuracy is fundamentally constrained by the trade-off between true and false positives. Increased true positives are possible only at the cost of increased false positives; conversely, decreased false positives are associated with de...
Preprint
Resource availability and sociality are tightly coupled. Sociality facilitates resource access in a wide range of animal species. Simultaneously, resource availability may change sociality. However, experimental evidence for resource-driven social changes in the wild, beyond local aggregations at the resource, remains scarce. Moreover, it is largel...
Article
Recent comparative studies of billfishes (Istiophoridae and Xiphiidae) have provided evidence of differences in the form and function of the rostra (bill) among species. Here, we report the discovery of a new structure, lacuna rostralis, on the rostra of sailfish Istiophorus platypterus, which is absent on the rostra of swordfish Xiphias gladius, s...
Article
The collective behavior of animals has attracted considerable attention in recent years, with many studies exploring how local interactions between individuals can give rise to global group properties.1, 2, 3 The functional aspects of collective behavior are less well studied, especially in the field,⁴ and relatively few studies have investigated t...
Article
Full-text available
A key benefit of sociality is a reduction in predation risk. Cohesive group behaviour and rapid collective decision making are essential for reducing predation risk in groups. Parasite infection might reduce an individuals’ grouping behaviours and thereby change the behaviour of the group as a whole. To investigate the relationship between parasite...
Article
Rules form an important part of our everyday lives. Here we explore the role of social influence in rule-breaking. In particular, we identify some of the cognitive mechanisms underlying rule-breaking and propose approaches for how they can be scaled up to the level of groups or crowds to better understand the emergence of collective rule-breaking....
Article
Full-text available
Bird predation poses a strong selection pressure on fish. Since birds must enter the water to catch fish, a combination of visual and mechano-acoustic cues (multimodal) characterize an immediate attack, while single cues (unimodal) may represent less dangerous disturbances. We investigated whether fish could use this information to distinguish betw...
Data
In recent years, the incorporation of lower levels of organization to the understanding of population ecology, has led to an increase in interest for animal personality and individual foraging specialization. Despite these topics investigating comparable phenomena, that is, individual consistency in behaviour and in food resource use respectively,...
Article
Full-text available
In recent years, the incorporation of lower levels of organization to the understanding of population ecology, has led to an increase in interest for animal personality and individual foraging specialization. Despite these topics investigating comparable phenomena, i.e. individual consistency in behavior and in food resource use respectively, they...
Article
Full-text available
Decision makers in contexts as diverse as medical, judicial and political decision making are known to differ substantially in response bias and accuracy, and these differences are a major factor undermining the reliability and fairness of the respective decision systems. Using theoretical modelling and empirical testing across five domains, we sho...
Article
Biomimetic robots that replace living social interaction partners can help elucidate the underlying interaction rules in animal groups. Our review focuses on the use of interactive robots that respond dynamically to animal behavior as part of a closed control loop. We discuss the most influential works to date and how they have contributed to our u...
Article
Full-text available
Animals often face changing environments, and behavioral flexibility allows them to rapidly and adaptively respond to abiotic factors that vary more or less regularly. However, abiotic factors that affect prey species do not necessarily affect their predators. Still, the prey’s response might affect the predator indirectly, yet evidence from the wi...
Article
Full-text available
Mate choice that is based on behavioural traits is a common feature in the animal kingdom. Using the Trinidadian guppy, a species with mutual mate choice, we investigated whether males use female swimming activity—a behavioural trait known to differ consistently among individuals in many species—as a trait relevant for their mate choice. In the fir...
Article
Making fast and accurate group decisions under uncertain and risky conditions is a fundamental problem for groups. Currently, there is little empirical evidence of how natural selection (such as environmental predation risk) has shaped the mechanisms of group decision making. We repeatedly tested individually marked guppies, Poecilia reticulata, fr...
Article
Full-text available
Sociality is a fundamental organizing principle across taxa, thought to come with a suite of adaptive benefits. However, making causal inferences about these adaptive benefits requires experimental manipulation of the social environment, which is rarely feasible in the field. Here we manipulated the number of conspecifics in Trinidadian guppies (Po...
Preprint
Mate choice that is based on behavioural traits is a common feature in the animal kingdom. Using the Trinidadian guppy, a species with mutual mate choice, we investigated whether males use female swimming activity – a behavioural trait known to differ consistently among individuals in many species – as a trait relevant for their mate choice. In a f...
Article
Full-text available
Understanding the linkage between behavioral types and dispersal tendency has become a pressing issue in light of global change and biological invasions. Here, we explore whether dispersing individuals exhibit behavioral types that differ from those remaining in the source population. We investigated a feral population of guppies (Poecilia reticula...
Chapter
Biomimetic robots that are accepted as social partners by animals may help to gain insights into animals’ social interaction skills. Here, we present an experiment using the biomimetic Robofish which resembles live guppies (Poecilia reticulata) - a small tropical freshwater fish. Guppy females were given the opportunity to interact with different o...
Article
Full-text available
Many prey species have evolved collective responses to avoid predation. They rapidly transfer information about potential predators to trigger and coordinate escape waves. Predation avoidance behaviour is often manipulated by trophically transmitted parasites, to facilitate their transmission to the next host. We hypothesized that the presence of i...
Article
Full-text available
Understanding the emergence of collective behaviour has long been a key research focus in the natural sciences. Besides the fundamental role of social interaction rules, a combination of theoretical and empirical work indicates individual speed may be a key process that drives the collective behaviour of animal groups. Socially induced changes in s...
Preprint
Full-text available
Collective motion is commonly modeled with simple interaction rules between agents. Yet in nature, numerous observables vary within and between individuals and it remains largely unknown how animals respond to this variability, and how much of it may be the result of social responses. Here, we hypothesize that Guppies (\textit{Poecilia reticulata})...
Preprint
Full-text available
Sociality is a fundamental organizing principle across taxa, thought to come with a suite of adaptive benefits. However, making causal inferences about these adaptive benefits requires experimental manipulation of the social environment, which is rarely feasible in the field. Here we manipulated the number of conspecifics in Trinidadian guppies (Po...
Article
Billfishes are well-known for their distinctive elongated rostra, a.k.a. bills. The functional significance of billfish rostra has been frequently discussed and the recent discovery of an oil gland (glandula oleofera) at the base of the rostrum in swordfish, Xiphias gladius , has added an interesting facet to this discussion regarding the potential...
Article
Full-text available
1. Consistent individual differences in behaviour (i.e. personality) can be explained in an evolutionary context if they are favoured by life history trade-offs as conceptualized in the pace-of-life syndrome (POLS) hypothesis. Theory predicts that faster-growing individuals suffer higher mortality and that this trade-off is mediated through explora...
Data
1) Consistent individual differences in behaviour (i.e. personality) can be explained in an evolutionary context if they are favoured by life-history trade-offs as conceptualized in the pace-of-life syndrome (POLS) hypothesis. Theory predicts that faster growing individuals suffer higher mortality and that this trade-off is mediated through explora...
Preprint
Full-text available
Over the last decades, the relative benefits and costs of individual vs. collective decision-making systems have attracted ample attention in the behavioural sciences and beyond. This research however, has almost exclusively focused on accuracy as a performance criterion, neglecting another major performance dimension of decision-making systems, th...
Preprint
Full-text available
Understanding the emergence of collective behaviour has long been a key research focus in the natural sciences. Besides the fundamental role of social interaction rules, a combination of theoretical and empirical work indicates individual speed may be a key process that drives the collective behaviour of animal groups. Socially-induced changes in s...
Article
Full-text available
Body size is often assumed to determine how successfully an individual can lead others with larger individuals being better leaders than smaller ones. But even if larger individuals are more readily followed, body size often correlates with specific behavioral patterns and it is thus unclear whether larger individuals are more often followed than s...
Article
Full-text available
Animals often show high consistency in their social organisation despite facing changing environmental conditions. Especially in shoaling fish, fission–fusion dynamics that describe for which periods individuals are solitary or social have been found to remain unaltered even when density changed. This compensatory ability is assumed to be an adapta...
Preprint
Full-text available
Understanding the linkage between behavioral types and dispersal tendency has become a pressing issue in light of global change and biological invasions. Here, we explore whether dispersing individuals exhibit behavioral types that differ from those remaining in the source population. We investigated a feral population of guppies ( Poecilia reticul...
Article
Full-text available
Personality traits (i.e. consistent individual differences in behaviour) often covary, forming behavioural syndromes. Such associations, if driven by an underlying proximate mechanism, could limit the independent evolution of each behaviour. In contrast, a behavioural syndrome may be the result of selection favouring the behavioural correlation und...
Article
Full-text available
Linking morphological differences in foraging adaptations to prey choice and feeding strategies has provided major evolutionary insights across taxa. Here, we combine behavioural and morphological approaches to explore and compare the role of the rostrum (bill) and micro-teeth in the feeding behaviour of sailfish (Istiophorus platypterus) and strip...
Article
Full-text available
Distinguishing between high- and low-performing individuals and groups is of prime importance in a wide range of high-stakes contexts. While this is straightforward when accurate records of past performance exist, these records are unavailable in most real-world contexts. Focusing on the class of binary decision problems, we use a combined theoreti...
Article
Full-text available
Responding to the information provided by others is an important foraging strategy in many species. Through social foraging, individuals can more efficiently find unpredictable resources and thereby increase their foraging success. When individuals are more socially responsive to particular phenotypes than others, however, the advantage they obtain...
Article
Full-text available
Collective decision-making is ubiquitous, and majority-voting and the Condorcet Jury Theorem pervade thinking about collective decision-making. Thus, it is typically assumed that majority-voting is the best possible decision mechanism, and that scenarios exist where individually-weak decision-makers should not pool information. Condorcet and its ap...
Preprint
Full-text available
Distinguishing between high- and low-performing individuals and groups is of prime importance in a wide range of high-stakes contexts. While this is straightforward when accurate records of past performance exist, in most real-world contexts, such records are unavailable. Focusing on the class of binary decision problems, we use a combined theoreti...
Article
Science requires replication. The development of many cloned or isogenic model organisms is a testament to this. But researchers are reluctant to use these traditional animal model systems for certain questions in evolution or ecology research, because of concerns over relevance or inbreeding. It has largely been overlooked that there are a substan...
Preprint
Full-text available
BioRxiv link to article: https://doi.org/10.1101/478537 When individuals are more socially responsive to one sex than the other, the benefits they get from foraging socially are likely to depend on the sex composition of the social environment. We tested this hypothesis by performing experimental manipulations of guppy, Poecilia reticulata, sex co...
Article
Full-text available
Individual foraging is under strong natural selection. Yet, whether individuals differ consistently in their foraging success across environments, and which individual- and population-level traits might drive such differences, is largely unknown. We addressed this question in a field experiment, conducting over 1,100 foraging trials with subpopulat...
Preprint
Full-text available
We compared the social dynamics of two populations of the live-bearing Atlantic molly (Poecilia mexicana) that live in adjacent habitats with very different predator regimes: cave mollies that inhabit a low-predation environment inside a sulfidic cave with a low density of predatory water bugs (Belostoma sp.), and mollies that live directly outside...
Article
Full-text available
Artificial light at night (ALAN) is a major form of anthropogenic pollution. ALAN is well known to affect different behaviours during nighttime, when changes in light conditions often have immediate consequences for the trade-offs individuals experience. How ALAN affects daytime behaviours, however, has received far less attention. Here we studied...
Preprint
Full-text available
Majority-voting and the Condorcet Jury Theorem pervade thinking about collective decision-making. Thus, it is typically assumed that majority-voting is the best possible decision mechanism, and that scenarios exist where individually-weak decision-makers should not pool information. Condorcet and its applications implicitly assume that only one kin...
Article
Majority-voting and the Condorcet Jury Theorem pervade thinking about collective decision-making. Thus, it is typically assumed that majority-voting is the best possible decision mechanism, and that scenarios exist where individually-weak decision-makers should not pool information. Condorcet and its applications implicitly assume that only one kin...
Article
Full-text available
Responding towards the actions of others is one of the most important behavioural traits whenever animals of the same species interact. Mutual influences among interacting individuals may modulate the social responsiveness seen and thus make it often difficult to study the level and individual variation in responsiveness. Here, open-loop biomimetic...
Article
Full-text available
Trophically transmitted parasites frequently increase their hosts' risk-taking behaviour, to facilitate transmission to the next host. Whether such elevated risk-taking can spill over to uninfected group members is, however, unknown. To investigate this, we confronted groups of 6 three-spined sticklebacks, Gasterosteus aculeatus, containing 0, 2, 4...
Article
Collective intelligence refers to the ability of groups to outperform individuals in solving cognitive tasks. Although numerous studies have demonstrated this effect, the mechanisms underlying collective intelligence remain poorly understood. Here, we investigate diversity in cue beliefs as a mechanism potentially promoting collective intelligence....
Preprint
Full-text available
Responding towards the actions of others is one of the most important behavioral traits whenever animals of the same species interact. Mutual influences among interacting individuals may modulate the social responsiveness 19 seen and thus makes it often difficult to study the level and variation of individuality in responsiveness. Here, biomimetic...
Article
An animal's position within a group affects feeding - front positions generally offer richer pickings. However, a new study shows that position can be influenced by feeding because big meals reduce scope for locomotion.
Preprint
Full-text available
Individual foraging is under strong natural selection. Yet, whether individuals differ consistently in their foraging success across environments, and which individual and population-level traits might drive such differences, is largely unknown. We addressed this question in a field experiment, conducting over 1,100 foraging trials with nine subpop...
Article
Full-text available
Biomimetic robots (BRs) are becoming more common in behavioral research and, if they are accepted as conspecifics, allow for new forms of experimental manipulations of social interactions. Nevertheless, it is often not clear which cues emanating from a BR are actually used as communicative signals and how species or populations with different senso...
Article
Full-text available
Despite substantial research interest in understanding individual-level consistency in behavioral attributes, significant knowledge gaps remain across traits and taxa. For example, relatively few studies have looked at social personality in large marine species such as elasmobranchs and whether or not individual differences in behavior are maintain...
Article
Full-text available
Predation is thought to shape the macroscopic properties of animal groups, making moving groups more cohesive and coordinated. Precisely how predation has shaped individuals' fine-scale social interactions in natural populations, however, is unknown. Using high-resolution tracking data of shoaling fish (Poecilia reticulata) from populations differi...
Article
Full-text available
The costs and benefits of group living often depend on the spatial position of individuals within groups and the ability of individuals to occupy preferred positions. For example, models of predation events for moving prey groups predict higher mortality risk for individuals at the periphery and front of groups. We investigated these predictions in...
Article
The social network approach has focused increasing attention on the complex web of relationships found in animal groups and populations. As such, network analysis has been used frequently to identify the role that particular individuals play in their social interactions and this approach has led to the question of whether, and in what context, indi...
Article
Full-text available
Collective cognition has received much attention in recent years but most of the empirical work has focused on comparing individuals and groups within single populations, thereby not addressing evolutionary origins of collective cognition. Here, we investigated collective cognition in multiple populations that are subject to different levels of pre...
Article
Lateralization is widespread throughout the animal kingdom [1-7] and can increase task efficiency via shortening reaction times and saving on neural tissue [8-16]. However, lateralization might be costly because it increases predictability [17-21]. In predator-prey interactions, for example, predators might increase capture success because of speci...