An assessment of optimal foraging in honeybees through decoding of waggle dances in an urban landscape

A global decline of honeybees (Apis mellifera) and other pollinators which are essential for pollinating crops and wild flowers has been reported throughout the last decades. One major cause is the loss of available resources due to agricultural intensification. Especially urban areas seem to become an important habitat for pollinators. In 2017, Stange et al. developed a habitat suitability model for pollinators indicating habitat quality in terms of available floral resources and nesting sites for the City of Oslo, Norway. Our aim was to analyse whether the foraging patterns of honeybees match with highly suitable habitat patches as indicated by the ESTIMAP model. According to the optimal foraging theory honeybees should visit the closest and most rewarding habitat patches from the hive location, maximizing energetic intake per unit time. Hence, we hypothesised that patches which were frequently visited by the studied honeybees also had a high habitat suitability value and vice versa. We studied honeybee foraging patterns over the summer 2017 by decoding 506 waggle dances from three bee colonies located at two study sites in the urban area of Oslo. The waggle dance is a communication tool of successful foragers to indicate rewarding resource locations to their nestmates. We used this unique behavioural trait to analyse how the used foraging patches of our honeybees are correlated with values of the ESTIMAP model by applying a beta regression model. Moreover, we examined to what extent the foraging patterns of two bee colonies placed in the same environment overlapped. After decoding the dances, the foraging patterns showed that visitation probabilities of used patches were only for one location correlated with the habitat suitability values of the ESTIMAP model. Furthermore, we ascertained that there was also only a mediocre overlap between the foraging patterns of the two hives located next to each other. In general, most of the foraging took place close to the hive locations. With a mean foraging distance of 688 m, 490 m and 425 m respectively, the mean foraging distances of the three urban bee colonies are much shorter than the foraging distances from their colleagues in rural areas. Factors that lead to the moderate correlation between the visitation probabilities of the decoded waggle dances and the ESTIMAP values as well as of the foraging pattern of the hives placed in the same environment can be of various nature. First, by decoding waggle dances we did not have insight where honeybees of other hives or wild pollinators forage. Thus, high suitability habitat patches might have been exploited by other bees. Secondly, human error in the process of decoding the waggle dances might cause some inaccuracy in plotting the foraging patterns of our honeybees. Overall, our study raises more interesting questions about the resource selection of honeybees and suggests that next to the distance and the nectar-reward of the floral resources, also the exploitative competition by other bees might play a role in the resource selection of honeybees

Analysis and network simulations of honeybee interneurons responsive to waggle dance vibration signals

BACKGROUND: Honeybees have long fascinated neuroscientists with their highly evolved social structure and rich behavioral repertoire. They sense air vibrations with their antennae, which is vital for several activities during foraging, like waggle dance communication and flight. GOALS: This thesis presents the investigation of the function of an identified vibration-sensitive interneuron, DL-Int-1. Primary goals were the investigation of (i) adaptations during maturation and (ii) the role of DL-Int-1 in networks encoding distance information of waggle dance vibration signals. RESULTS: Visual inspection indicated that DL-Int-1 morphologies had similar gross structure, but were translated, rotated and scaled relative to each other. To enable detailed spatial comparison, an algorithm for the spatial co-registration of neuron morphologies, Reg-MaxS-N was developed and validated. Experimental data from DL-Int-1 was provided by our Japanese collaborators. Comparison of morphologies from newly emerged adult and forager DL-Int-1 revealed minor changes in gross dendritic features and consistent, region-dependent and spatially localized changes in dendritic density. Comparison of electrophysiological response properties showed an increase in firing rate differences between stimulus and non-stimulus periods during maturation. A putative disinhibitory network in the honeybee primary auditory center was proposed based on experimental evidence. Simulations showed that the network was consistent with experimental observations and clarified the central inhibitory role of DL-Int-1 in shaping the network output. RELEVANCE: Reg-MaxS-N presents a novel approach for the spatial co-registration of morphologies. Adaptations in DL-Int-1 morphology during maturation indicate improved connectivity and signal propagation. The central role of DL-Int-1 in a disinhibitory network in the honeybee primary auditory center combined with adaptions in its response properties during maturation could indicate better encoding of distance information from waggle dance vibration sig- nals

Bee-ing There: The Systematicity of Honeybee Navigation Supports a Classical Theory of Honeybee Cognition

The Classical theory of cognition proposes that there are cognitive processes that are computations defined over syntactically specified representations, "sentences" in a language of thought, for which the representational-constituency relation is concatenative. The main rival to Classicism is(Nonimplementational, or Radical, Distributed) Connectionism. It proposes that cognitive processes are computations defined over syntactically simple, distributed representions, for which the constituency relation is nonconcatenative. I argue that Connectionism, unlike Classicism, fails to provide an adequate theoretical framework for explaining systematically related cognitive capacities and that this is due to its necessary reliance on nonconcatenative constituency. There appears to be an interesting divergence of attitude among philosophers of psychology and cognitive scientists regarding Classicism's language of thought hypothesis. On one extreme, there are those who argue that only humans are likely to possess a language of thought (or that we at least have no evi- dence to the contrary). On the other extreme, there are those who argue that distinctively human thinking is not likely to be explicable in terms of a language of thought. They point to features of human cognition which they claim strongly support the hypothesis that human cognitive-state transition functions are computationally intractable. This implicitly suggests that the cognitive processes of simpler, nonhuman minds might be computationally tractable and thus amenable to Classical computational explanation. I review much of the recent literature on honeybee navigation. I argue that many capacities of honeybees to acquire various sorts of navigational information do in fact exhibit systematicity. That conclusion, together with the correctness of the view that Classicism provides a better theoretical framework than does Connectionism for explaining the systematicity of the relevant cognitive capacities, gives one reason in support of the claim that sophisticated navigators like honeybees have a kind of language of thought. At the very least, it provides one reason in support of the claim that the constituency relation for the mental representations of such navigators is concatenative, not nonconcatenative

Bumblebees in a Changing Climate: Evaluating the Effects of Temperature on Queen Performance

Bumblebees are a very essential group of pollinating insects, but their populations have declined drastically during the past decades. We need to understand why their numbers are decreasing and what can be done to reverse this trend. Climate change-related phenomena, such as changes in the overwintering temperatures and spring conditions, are among the most prominent threats to bumblebees. Queens have a special role in the lifecycle of bumblebees because they overwinter and start new colonies the next year. Their successful performance: survival, overwintering ability, longevity, immune competence, and nest establishing capability in spring, is highly important for bumblebee populations. However, the effects of climate change on bumblebee queen performance remain unknown. The main objective of this thesis was to assess how temperature affects the performance of bumblebee queens during and after overwintering. The effects of warm temperature predicted by climate change scenarios on queen survival and stress-tolerance were studied by a four-month artificial diapause of bumblebee queens at two temperatures (9°C and 1.8°C). Bumblebee colonies were also reared in a laboratory and factors affecting colony characteristics were examined. In addition, queen performance during spring was studied in a starvation experiment using two temperatures (15°C as normal; 24°C as warmer than average) and queens collected from nature right after their emergence. My research revealed how temperature affects queen performance, and queen size was found to be an important factor determining the direction of some of these effects. We found a 0.4g weight threshold for bumblebee queens to be able to survive overwintering. In addition, during mild winters, larger queens have a higher chance than smaller ones to survive through winter and also to cope with immunological stresses after overwintering. During cold conditions, which are normal in the current climatic situation, this advantage disappears. In the spring starvation experiment, the starved queens survived approximately eight days longer in 15°C than in 24°C, which means that starvation risk rises significantly with increasing spring temperature, in a situation where food is scarce due to for example frost damage or asynchrony between bumblebees and their important food plants. These results could mean that in the future climate, larger queens are better able to survive the winter, initiate their nests and start rearing their offspring. This may be problematic, because I also detected two alternative strategies of colony development that differ between large and small queens; larger queens start to lay eggs earlier at nest initiation, their colonies mature later, they produce more workers, and they have a more strongly male biased sex allocation compared with smaller queens. If larger queens have a greater change of producing offspring after a mild winter, this could lead to a significant decline in the total production of new queens at a population level. Thus, it seems that queen size could act as one mechanism regulating the population level outcomes in different temperatures. The new information presented in my thesis reinforces that basic research, monitoring, and local species conservation of bumblebees both in Finland and globally must be increased to ensure that this highly important pollinator group survives in the face of climate change.Siirretty Doriast

Analysis and network simulations of honeybee interneurons responsive to waggle dance vibration signals

BACKGROUND: Honeybees have long fascinated neuroscientists with their highly evolved social structure and rich behavioral repertoire. They sense air vibrations with their antennae, which is vital for several activities during foraging, like waggle dance communication and flight. GOALS: This thesis presents the investigation of the function of an identified vibration-sensitive interneuron, DL-Int-1. Primary goals were the investigation of (i) adaptations during maturation and (ii) the role of DL-Int-1 in networks encoding distance information of waggle dance vibration signals. RESULTS: Visual inspection indicated that DL-Int-1 morphologies had similar gross structure, but were translated, rotated and scaled relative to each other. To enable detailed spatial comparison, an algorithm for the spatial co-registration of neuron morphologies, Reg-MaxS-N was developed and validated. Experimental data from DL-Int-1 was provided by our Japanese collaborators. Comparison of morphologies from newly emerged adult and forager DL-Int-1 revealed minor changes in gross dendritic features and consistent, region-dependent and spatially localized changes in dendritic density. Comparison of electrophysiological response properties showed an increase in firing rate differences between stimulus and non-stimulus periods during maturation. A putative disinhibitory network in the honeybee primary auditory center was proposed based on experimental evidence. Simulations showed that the network was consistent with experimental observations and clarified the central inhibitory role of DL-Int-1 in shaping the network output. RELEVANCE: Reg-MaxS-N presents a novel approach for the spatial co-registration of morphologies. Adaptations in DL-Int-1 morphology during maturation indicate improved connectivity and signal propagation. The central role of DL-Int-1 in a disinhibitory network in the honeybee primary auditory center combined with adaptions in its response properties during maturation could indicate better encoding of distance information from waggle dance vibration sig- nals

Beasts in Collaboration: A Study of Biomimicry and Evolutionary Principles applied to Management Innovation

This research describes the frontier of bio-inspired management innovation and how it may lead to a paradigm shift in how we structure and lead organizations. As an exploratory foray into a subculture of bio-inspired experts, it asks how we might apply evolutionary principles to creating more resilient and adaptive organizations. The experts hail from both science-based and organizational management backgrounds, showcasing a distinct divergence in how biomimicry is applied in their work. A review of contributions from these pioneering practitioners discovers the impetus and resulting benefits of their application. This is contrasted with the barriers that currently limit further development of biomimicry for organizational change. Ultimately there remains a common understanding among these practitioners that involves the intention to learn from nature. The research therefore analyzes the study of nature for informed and intentional change, and provides examples of edge corporations leading the way. As we are frantically racing to reverse the consequences of our actions on the planet’s finite resources, the potential for a new paradigm that might consciously change how we model our organizations will have a direct impact on our resilience as a species

Haptic communication between partner dancers and swing as a finite state machine

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Vita.Includes bibliographical references (p. 129-138).To see two expert partners, one leading and the other following, swing dance together is to watch a remarkable two-agent communication and control system in action. Even blindfolded, the follower can decode the leader's moves from haptic cues. The leader composes the dance from the vocabulary of known moves so as to complement the music he is dancing to. Systematically addressing questions about partner dance communication is of scientific interest and could improve human-robotic interaction, and imitating the leader's choreographic skill is an engineering problem with applications beyond the dance domain. Swing dance choreography is a finite state machine, with moves that transition between a small number of poses. Two automated choreographers are presented. One uses an optimization and randomization scheme to compose dances by a sequence of shortest path problems, with edge lengths measuring the dissimilarity of dance moves to each bar of music. The other solves a two-player zero-sum game between the choreographer and a judge. Choosing moves at random from among moves that are good enough is rational under the game model.(cont.) Further, experiments presenting conflicting musical environments to two partners demonstrate that although musical expression clearly guides the leader's choice of moves, the follower need not hear the same music to properly decode the leader's signals. Dancers embody gentle interaction, in which each participant extends the capabilities of the other, and their cooperation is facilitated by a shared understanding of the motions to be performed. To demonstrate that followers use their understanding of the move vocabulary to interact better with their leaders, an experiment paired a haptic robot leader with human followers in a haptically cued dance to a swing music soundtrack. The subjects' performance differed significantly between instances when the subjects could determine which move was being led and instances when the subjects could not determine what the next move would be. Also, two-person teams that cooperated haptically to perform cyclical aiming tasks showed improvements in the Fitts' law or Schmidt's law speed-accuracy tradeoff consistent with a novel endpoint compromise hypothesis about haptic collaboration.by Sommer Elizabeth Gentry.Ph.D

Reinforcement learning of visually guided spatial goal directed movement

A range of visually guided, spatial goal directed tasks are investigated, using a computational neuroethology approach. Animats are embedded within a bounded, 2-D environment, and map a 1-D visual array, through a convolution network, to a topography preserving motor array that stochastically determines the direction of movement. Temporal difference reinforcement learning modifies the convolution network in response to a reinforcement signal received only at the goal location. Three forms of visual coding are compared: multiscale coding, where the visual array is convolved by Laplacian of Gaussian filters at a range of spatial scales before convolution to determine the motor array; rectified multiscale coding, where the multiscale array is split into positive and negative components; and intensity coding, where the unfiltered visual array is convolved to determine the motor array. After learning, animats are examined in terms of performance, behaviour and internal structure. When animats learn to approach a solitary circle, of randomly varying contrast, rectified multiscale coding animats learn to outperform multiscale and intensity coding animats in both independent and coarse scale noise conditions. Analysis of the learned internal structure shows that rectified multiscale filtering facilitates learning by enabling detection of the circle at scales least affected by noise. Cartwright and Collett (1983) showed that honeybees learn the angle subtended by a featureless landmark to guide movement to a food source at a fixed distance from the landmark, and furthermore, when tested with only the edges of the landmark, still search in the same location. In a simulation of this experiment, animats are reinforced for moving to where the angle subtended by a solitary circle falls within a certain range. Rectified multiscale filtering leads to better performing animats, with fewer hidden units, in both independent and coarse scale visual noise conditions, though for different reasons in each case. Only those animats with rectified multiscale filtering, that learn in the presence of coarse scale noise, show similar generalisation to the honeybees. Collett, Cartwright and Smith (1986) trained gerbils to search at locations relative to arrangemments of landmarks and tested their search patterns in modifications of the training arrangements. These experiments are simulated with landmark distance coded as either a 1-D intensity array, or a 2-D vector array, plus a simple compass sense. Vector coding animats significantly outperform those using intensity coding and do so with fewer hidden units. Furthermore, vector coding animats show a close match to gerbil behaviour in tests with modified landmark arrangements

Communication and cooperation in evolutionary biology

How can the concepts and results of communication theory aid evolutionary biology? This thesis argues for an explanatory framework, evolutionary communication theory, that interprets and illuminates scientific research into the phenomenon of biological signalling. By expanding the theory beyond the models and goals familiar to Claude Shannon and other engineers, real insight is gained into how strategic interplay between senders and receivers shapes signal form. Furthermore, interpreting artificial and natural signals in terms of sender-receiver teleosemantics demonstrates the explanatory role of relations borne between signals and world affairs. One of the major results of the thesis is a rejection of the orthodox distinction between Shannon and semantic information. While there are at least two useful distinctions to be drawn -- between cues and signals, and between statistical and functional content -- the terminological confusion that gave rise to the phrase `Shannon information' should be put aside for good. Chapter 1 outlines a way to capture the relationships between signals and other signal-like interactions using a multi-dimensional conceptual space called a hypercube. I argue that sender-receiver teleosemantics is uniquely well suited to capturing those aspects of communication theory that render it a viable mathematical framework for evolutionary biology. Chapter 2 discusses an early attempt to apply communication theory in evolutionary biology. Haldane & Spurway's informational interpretation of the honeybee waggle dance has recently been criticised on mathematical grounds. These criticisms lend support to scepticism about the relevance of information for evolutionary biology. I argue that the criticisms are themselves mathematically erroneous, so one route to scepticism about information is undercut. Chapter 3 explores a related line of scepticism. It is common in the philosophy of biology to treat the concepts and tools of communication theory as insufficient or irrelevant for analysing semantic content. I argue that the grounds of this supposition are based on misinterpretations of some features of communication theory. In chapter 4 I reconstruct Millikan's teleosemantics in a causal-modelling setting, highlighting the explanatory role of semantic content. In chapter 5 I respond to objections to the teleosemantic account, including the claim that the theory renders explanations of success that appeal to semantic content circular. I also argue for an interpretation of important features of communication-theoretic models in terms of teleosemantics. Chapter 6 explores another challenge to applying teleosemantics to biological signals. The theory places emphasis on cooperation between senders and receivers, but biological signals are often fraught with evolutionary conflict. I discuss recent formal work, and argue that prospects for teleosemantics are good. Finally, in chapter 7 I argue that an explanatory framework that draws on communication-theoretic concepts would be beneficial to evolutionary biology. I present case studies of communicative behaviour for which biologists offer explanations that are well interpreted through the principles of communications engineering

An Insect View of its Plain : Nature and Insects in Thoreau, Dickinson, and Muir

The simultaneous emergence of ecocriticism and cultural entomology has created a critical need for a discussion of the appearance and function of insects as they appear in literature. While nineteenth-century nature writing is frequently examined by ecocritics, very few have chosen to explore how critical writers such as Henry David Thoreau, Emily Dickinson, and John Muir incorporate insects into their work. This study explores three interrelated issues connected to encounters with and explorations of the microscopic and unacknowledged position of insects in nature: first, how insects factor into their growing knowledge about nature and ecology; second, how nature serves as a conduit to or inspiration for spirituality, revealing in its intricate processes the messages of the divine; and third, how insects are important not only for their critical ecological function but also for their symbolic value in suggesting the possibility of a renewed connection and relationship with the natural world and God, either through an awareness of ecological integration, an acknowledgement that all life participates in a joyous celebration of creation and has a right to exist, or a metamorphic process that unites the physical and spiritual in an attempt to transcend earthly experience. The introduction of this dissertation discusses how the evolution of ecocriticism establishes the legitimacy and importance of an insect\u27s point of view. Chapter one provides a partial cultural portrait of insects in the nineteenth century, examining insects in science, agriculture, folklore, fashion, religion, and literature. Chapter two focuses on Thoreau\u27s interpretation of the song of the crickets as a universal choir which nature continually invites humanity to join, on his interest in the reflective eyes of the water-skaters of Walden and their ability to exist between the margins of heaven and earth, and on his fascination with the process of metamorphosis in relation to both insects and human potential. Chapter three explores Dickinson\u27s vision of nature as an interdependent society of insects, animals, and plants, each having an important and unique purpose to fulfill, and her complex attitude toward cocoons and metamorphosis, especially in relation to her fear of death and uncertainly about salvation. Chapter four establishes Muir as a true lover of nature who views insects and all other citizens of creation as his brothers, equal members in a creation designed and lovingly maintained by God. Muir is especially interested in bees, attempting to adopt their point of view when he describes the flowers of California and idealizing apiculture as a form of agriculture in harmony with the needs of both nature and humanity