Computational model of collective nest selection by ants with heterogeneous acceptance thresholds

Collective decision-making is a characteristic of societies ranging from ants to humans. The ant Temnothorax albipennis is known to use quorum sensing to collectively decide on a new home; emigration to a new nest site occurs when the number of ants favouring the new site becomes quorate. There are several possible mechanisms by which ant colonies can select the best nest site among alternatives based on a quorum mechanism. In this study, we use computational models to examine the implications of heterogeneous acceptance thresholds across individual ants in collective nest choice behaviour. We take a minimalist approach to develop a differential equation model and a corresponding non-spatial agent-based model. We show, consistent with existing empirical evidence, that heterogeneity in acceptance thresholds is a viable mechanism for efficient nest choice behaviour. In particular, we show that the proposed models show speed–accuracy trade-offs and speed–cohesion trade-offs when we vary the number of scouts or the quorum threshold

The emergence and development of behavioral individuality in clonal fish

Behavioral individuality is a ubiquitous phenomenon in animal populations, yet the origins and developmental trajectories of individuality, especially very early in life, are still a black box. Using a high-resolution tracking system, we mapped the behavioral trajectories of genetically identical fish (Poecilia formosa), separated immediately after birth into identical environments, over the first 10 weeks of their life at 3 s resolution. We find that (i) strong behavioral individuality is present at the very first day after birth, (ii) behavioral differences at day 1 of life predict behavior up to at least 10 weeks later, and (iii) patterns of individuality strengthen gradually over developmental time. Our results establish a null model for how behavioral individuality can develop in the absence of genetic and environmental variation and provide experimental evidence that later-in-life individuality can be strongly shaped by factors predating birth like maternal provisioning, epigenetics and pre-birth developmental stochasticity

Exploration adjustment by ant colonies

© 2016 The Authors. How do animals in groups organize their work? Division of labour, i.e. the process by which individuals within a group choose which tasks to perform, has been extensively studied in social insects. Variability among individuals within a colony seems to underpin both the decision over which tasks to perform and the amount of effort to invest in a task. Studies have focused mainly on discrete tasks, i.e. tasks with a recognizable end. Here, we study the distribution of effort in nest seeking, in the absence of new nest sites. Hence, this task is open-ended and individuals have to decide when to stop searching, even though the task has not been completed. We show that collective search effort declines when colonies inhabit better homes, as a consequence of a reduction in the number of bouts (exploratory events). Furthermore, we show an increase in bout exploration time and a decrease in bout instantaneous speed for colonies inhabiting better homes. The effect of treatment on bout effort is very small; however, we suggest that the organization of work performed within nest searching is achieved both by a process of self-selection of the most hard-working ants and individual effort adjustment

How can Inclusive Citizen Science Transform the Sustainable Development Agenda? Recommendations for a Wider and More Meaningful Inclusion in the Design of Citizen Science Initiatives

Although there has been a sharp increase in citizen science (CS) initiatives in past years, barriers to participation are often too high for many social groups, including vulnerable social groups, making CS subject to the same exclusionary processes that are reflected on a wider societal level. This essay aims to start a conversation on achieving more inclusive practices in CS initiatives and integrating them into the 2030 Agenda for wider data representation. First, we present prior research findings on the importance and benefits of social inclusion to science, citizens, and society, and considerations when designing for inclusive participatory practices. Next, we highlight ongoing European research projects that are making substantial efforts towards CS inclusion (e.g., SOCIO-BEE). Then, we discuss how inclusive CS can advance the Sustainable Development Agenda in general and in several Sustainable Development Goals (SDGs) in particular. Finally, we put forward a set of 12 recommendations to design for inclusion in CS initiatives, ranging from more abstract ideas (e.g., centering the strategy around the margins, being open to making mistakes) to practical actions (e.g., involving intermediary organizations, using inclusive language, publishing participant demographics)

Social behaviour and collective motion in plant-animal worms

© 2016 The Author(s) Published by the Royal Society. All rights reserved. Social behaviour may enable organisms to occupy ecological niches that would otherwise be unavailable to them. Here, we test this major evolutionary prin- ciple by demonstrating self-organizing social behaviour in the plant-animal, Symsagittifera roscoffensis. These marine aceol flat worms rely for all of their nutrition on the algae within their bodies: hence their common name. We show that individual worms interact with one another to coordinate their movements so that even at low densities they begin to swim in small polarized groups and at increasing densities such flotillas turn into circular mills. We use computer simulations to: (i) determine if real worms interact socially by com- paring them with virtual worms that do not interact and (ii) show that the social phase transitions of the real worms can occur based only on local inter- actions between and among them. We hypothesize that such social behaviour helps the worms to form the dense biofilms or mats observed on certain sun- exposed sandy beaches in the upper intertidal of the East Atlantic and to become in effect a super-organismic seaweed in a habitat where macro-algal seaweeds cannot anchor themselves. Symsagittifera roscoffensis, a model organ- ism in many other areas in biology (including stem cell regeneration), also seems to be an ideal model for understanding how individual behaviours can lead, through collective movement, to social assemblages

Ботаника: морфология и систематика растений

В учебном пособии представлено содержание курса «Ботаника», относящееся к следующим модулям: морфология растений, систематика растений и основы фитоценологии. Материал учебного пособия содержит теоретические вопросы по основным темам курса, для некоторых тем предложен ход выполнения практических работ. Пособие проиллюстрировано рисунками, таблицами и схемами, помогающими в освоении учебного материала

Averting biodiversity collapse in tropical forest protected areas

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon¹⁻³. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses⁴⁻⁹. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world’s major tropical regions. Our analysis reveals great variation in reserve ‘health’: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.Keywords: Ecology, Environmental scienc

Familiarity increases aggressiveness among clonal fish

Understanding how animal groups form and function is a major goal in behavioural ecology. Both genetic relatedness and familiarity among group mates have been shown to be key mediators of group composition. However, disentangling the two in most species is challenging as the most familiar individuals are often the most related, and vice versa. The relatedness between individuals is constant, whereas familiarity is not, and so familiarity may be more likely to mediate interactions in dynamic environments. Here, we manipulated the level of familiarity among groups of the naturally clonal, and genetically identical, Amazon molly, Poecilia formosa, and monitored group behaviour in an open-field assay and when given the opportunity to forage. Contrary to our predictions, fish that were the most familiar with each other showed the highest levels of aggression. Additionally, fish that were less familiar with each other exhibited the highest group cohesion and took the longest to begin feeding, compared to the more familiar fish. These results suggest that familiarity may socially buffer individuals from the perception of risk in novel environments, such as is common in most behavioural assays designed to test group behaviour. Increases in aggression that are associated with increasing familiarity as shown here might be a mechanism by which fish maintain a fission–fusion society with important consequences for the patterns of associations in group-living animals

Effectiveness of animal conditioning interventions in reducing human–wildlife conflict: a systematic map protocol

BACKGROUND: Human–wildlife conflict (HWC), is currently one of the most pressing conservation challenges. We restrict ourselves here to wildlife behaviour that is perceived to negatively impact social, economic or cultural aspects of human life or to negatively impact species of conservation concern. HWC often involves wild animals consuming anthropogenic resources, such as crops or livestock, either out of necessity (loss of habitat and natural prey) or as consequence of opportunistic behaviour. A variety of interventions are undertaken to reduce HWC, differing in practicability, costs and social acceptance. One such non-lethal intervention is animal conditioning, a technique to reduce conflict by modifying the behaviour of ‘problem’ animals long-term. Conditioning changes associations animals have with resources or behaviours. Both via ‘punishment’ of unwanted behaviour and ‘rewarding’ of alternative behaviour, researchers aim to make expression of unwanted behaviour relatively less desirable to animals. Despite the potential, however, studies testing conditioning interventions have reported seemingly contradictory outcomes. To facilitate reduction of HWC via conditioning, we thus need to better understand if and when conditioning interventions are indeed effective. With this systematic map we intend to make the global evidence base for conditioning of free-ranging vertebrates more accessible to practitioners, to identify potential evidence clusters and effect modifiers for a subsequent systematic review and to highlight evidence gaps for future research. METHODS: We will compile evidence, including grey literature, from bibliographic databases, online search engines, specialist sites and expert contacts. Where possible, a Boolean-style full search string will be used, including Intervention and Outcome search terms. Searches will be conducted in English. Search comprehensiveness will be evaluated with an a priori list of benchmark articles. We will base inclusion of articles on presence of quantitative data, subject identity, comparator and outcome. Inclusion consistency checks will be performed with 10% of the titles, abstracts and full texts. We will assess validity of the literature base on basis of study design and sample size. Finally, we will develop a searchable literature database and an interactive evidence atlas along with a narrative synthesis of the evidence