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Journal of Insect Science (Online) May 2024Honey bees are the most important managed insect pollinators in the US and Canadian crop systems. However, the annual mortality of colonies in the past 15 years has been...
Honey bees are the most important managed insect pollinators in the US and Canadian crop systems. However, the annual mortality of colonies in the past 15 years has been consistently higher than historical records. Because they are eusocial generalist pollinators and amenable to management, honey bees provide a unique opportunity to investigate a wide range of questions at molecular, organismal, and ecological scales. Here, the American Association of Professional Apiculturists (AAPA) and the Canadian Association of Professional Apiculturists (CAPA) created 2 collections of articles featuring investigations on micro and macro aspects of honey bee health, sociobiology, and management showcasing new applied research from diverse groups studying honey bees (Apis mellifera) in the United States and Canada. Research presented in this special issue includes examinations of abiotic and biotic stressors of honey bees, and evaluations and introductions of various stress mitigation measures that may be valuable to both scientists and the beekeeping community. These investigations from throughout the United States and Canada showcase the wide breadth of current work done and point out areas that need further research.
Topics: Bees; Animals; Canada; United States; Beekeeping; Stress, Physiological; Pollination
PubMed: 38805646
DOI: 10.1093/jisesa/ieae055 -
IScience Jul 2023Plants advertise their presence by displaying attractive flowers, which pollinators use to locate a floral reward. Understanding how floral traits scale with reward... (Review)
Review
Plants advertise their presence by displaying attractive flowers, which pollinators use to locate a floral reward. Understanding how floral traits scale with reward status lies at the heart of pollination biology, because it connects the different interests of plants and pollinators. Studies on plant phenotype-reward associations often use different terms and concepts, which limits developing a broader synthesis. Here, we present a framework with definitions of the key aspects of plant phenotype-reward associations and provide measures to quantify them across different species and studies. We first distinguish between cues and signals, which are often used interchangeably, but have different meanings and are subject to different selective pressures. We then define honesty, reliability, and information content of floral cues/signals and provide ways to quantify them. Finally, we discuss the ecological and evolutionary factors that determine flower phenotype-reward associations, how context-dependent and temporally variable they are, and highlight promising research directions.
PubMed: 37426347
DOI: 10.1016/j.isci.2023.107093 -
Journal of the History of Biology Aug 2023When the sociobiology debate erupted in 1975, there were almost too many contributions to the heated exchanges between sociobiologists and their critics to count. In the...
When the sociobiology debate erupted in 1975, there were almost too many contributions to the heated exchanges between sociobiologists and their critics to count. In the fall of 1976, a Canadian educational film entitled Sociobiology: Doing What Comes Naturally sparked further controversy due to its graphic visuals and outrageous narration. While critics claimed the film was a promotional tool to further the sociobiological agenda in educational settings, sociobiologists quickly distanced themselves from the film and, in turn, accused the critics of consciously misrepresenting sociobiology by organizing showings of the film. Using audio, video, archival, and published sources, this paper explores the complicated history of Sociobiology: Doing What Comes Naturally and demonstrates how the public debate about the film reflects the positions, polemics, and polarization of the sociobiology debate as a whole.
PubMed: 37382807
DOI: 10.1007/s10739-023-09719-7 -
Frontiers in Insect Science 2023
PubMed: 38469501
DOI: 10.3389/finsc.2023.1186027 -
Journal of Comparative Physiology. A,... Jul 2023The neural basis underlying spatial orientation in arthropods, in particular insects, has received considerable interest in recent years. This special issue of the...
The neural basis underlying spatial orientation in arthropods, in particular insects, has received considerable interest in recent years. This special issue of the Journal of Comparative Physiology A seeks to take account of these developments by presenting a collection of eight review articles and eight original research articles highlighting hotspots of research on spatial orientation in arthropods ranging from flies to spiders and the underlying neural circuits. The contributions impressively illustrate the wide range of tools available to arthropods extending from specific sensory channels to highly sophisticated neural computations for mastering complex navigational challenges.
Topics: Animals; Arthropods; Orientation, Spatial; Space Perception; Insecta; Spiders
PubMed: 37198448
DOI: 10.1007/s00359-023-01635-9 -
Environment International Apr 2024Bumblebees are among the most important wild bees for pollination of crops and securing wildflower diversity. However, their abundance and diversity have been on a...
Bumblebees are among the most important wild bees for pollination of crops and securing wildflower diversity. However, their abundance and diversity have been on a steady decrease in the last decades. One of the most important factors leading to their decline is the frequent use of plant protection products (PPPs) in agriculture, which spread into forests and natural reserves. Mixtures of different PPPs pose a particular threat because of possible synergistic effects. While there is a comparatively large body of studies on the effects of PPPs on honeybees, we still lack data on wild bees. We here investigated the influence of the frequent fungicide Cantus® Gold (boscalid/dimoxystrobin), the neonicotinoid insecticide Mospilan® (acetamiprid) and their combination on bumblebees. Cognitive performance and foraging flights of bumblebees were studied. They are essential for the provisioning and survival of the colony. We introduce a novel method for testing four treatments simultaneously on the same colony, minimizing inter-colony differences. For this, we successfully quartered the colony and moved the queen daily between compartments. Bumblebees appeared astonishingly resilient to the PPPs tested or they have developed mechanisms for detoxification. Neither learning capacity nor flight activity were inhibited by treatment with the single PPPs or their combination.
Topics: Bees; Animals; Neonicotinoids; Fungicides, Industrial; Strobilurins; Insecticides; Pyridines; Biphenyl Compounds; Niacinamide
PubMed: 38554503
DOI: 10.1016/j.envint.2024.108608 -
Journal of Comparative Physiology. A,... Jul 2023Many arthropods and vertebrates use celestial signals such as the position of the sun during the day or stars at night as compass cues for spatial orientation. The... (Review)
Review
Many arthropods and vertebrates use celestial signals such as the position of the sun during the day or stars at night as compass cues for spatial orientation. The neural network underlying sky compass coding in the brain has been studied in great detail in the desert locust Schistocerca gregaria. These insects perform long-range migrations in Northern Africa and the Middle East following seasonal changes in rainfall. Highly specialized photoreceptors in a dorsal rim area of their compound eyes are sensitive to the polarization of the sky, generated by scattered sunlight. These signals are combined with direct information on the sun position in the optic lobe and anterior optic tubercle and converge from both eyes in a midline crossing brain structure, the central complex. Here, head direction coding is achieved by a compass-like arrangement of columns signaling solar azimuth through a 360° range of space by combining direct brightness cues from the sun with polarization cues matching the polarization pattern of the sky. Other directional cues derived from wind direction and internal self-rotation input are likely integrated. Signals are transmitted as coherent steering commands to descending neurons for directional control of locomotion and flight.
Topics: Animals; Grasshoppers; Brain; Insecta; Orientation, Spatial; Sunlight
PubMed: 36550368
DOI: 10.1007/s00359-022-01601-x -
Pharmaceuticals (Basel, Switzerland) Jan 2024The expression of GPCRs has been associated with schizophrenia, and their expression may induce morphological changes in brain regions responsible for schizophrenia and... (Review)
Review
The expression of GPCRs has been associated with schizophrenia, and their expression may induce morphological changes in brain regions responsible for schizophrenia and disease-specific behavioral changes. The articles included in this review were selected using keywords and databases of scientific research websites. The expressions of GPRs have different involvements in schizophrenia, some increase the risk while others provide protection, and they may also be potential targets for new treatments. Proper evaluation of these factors is essential to have a better therapeutic response with a lower rate of chronicity and thus improve the long-term prognosis.
PubMed: 38256919
DOI: 10.3390/ph17010085 -
Current Biology : CB Oct 2023Animals form a behavioral decision by evaluating sensory evidence on the background of past experiences and the momentary motivational state. In insects, we still lack...
Animals form a behavioral decision by evaluating sensory evidence on the background of past experiences and the momentary motivational state. In insects, we still lack understanding of how and at which stage of the recurrent sensory-motor pathway behavioral decisions are formed. The mushroom body (MB), a central brain structure in insects and crustaceans, integrates sensory input of different modalities with the internal state, the behavioral state, and external sensory context through a large number of recurrent, mostly neuromodulatory inputs, implicating a functional role for MBs in state-dependent sensory-motor transformation. A number of classical conditioning studies in honeybees and fruit flies have provided accumulated evidence that at its output, the MB encodes the valence of a sensory stimulus with respect to its behavioral relevance. Recent work has extended this notion of valence encoding to the context of innate behaviors. Here, we co-analyzed a defined feeding behavior and simultaneous extracellular single-unit recordings from MB output neurons (MBONs) in the cockroach in response to timed sensory stimulation with odors. We show that clear neuronal responses occurred almost exclusively during behaviorally responded trials. Early MBON responses to the sensory stimulus preceded the feeding behavior and predicted its occurrence or non-occurrence from the single-trial population activity. Our results therefore suggest that at its output, the MB does not merely encode sensory stimulus valence. We hypothesize instead that the MB output represents an integrated signal of internal state, momentary environmental conditions, and experience-dependent memory to encode a behavioral decision.
Topics: Animals; Mushroom Bodies; Neurons; Drosophila; Odorants; Brain; Insecta; Drosophila melanogaster
PubMed: 37657449
DOI: 10.1016/j.cub.2023.08.016 -
Journal of Comparative Physiology. A,... Jul 2023Efficient spatial orientation in the natural environment is crucial for the survival of most animal species. Cataglyphis desert ants possess excellent navigational... (Review)
Review
Efficient spatial orientation in the natural environment is crucial for the survival of most animal species. Cataglyphis desert ants possess excellent navigational skills. After far-ranging foraging excursions, the ants return to their inconspicuous nest entrance using celestial and panoramic cues. This review focuses on the question about how naïve ants acquire the necessary spatial information and adjust their visual compass systems. Naïve ants perform structured learning walks during their transition from the dark nest interior to foraging under bright sunlight. During initial learning walks, the ants perform rotational movements with nest-directed views using the earth's magnetic field as an earthbound compass reference. Experimental manipulations demonstrate that specific sky compass cues trigger structural neuronal plasticity in visual circuits to integration centers in the central complex and mushroom bodies. During learning walks, rotation of the sky-polarization pattern is required for an increase in volume and synaptic complexes in both integration centers. In contrast, passive light exposure triggers light-spectrum (especially UV light) dependent changes in synaptic complexes upstream of the central complex. We discuss a multisensory circuit model in the ant brain for pathways mediating structural neuroplasticity at different levels following passive light exposure and multisensory experience during the performance of learning walks.
Topics: Animals; Ants; Learning; Brain; Cues; Walking; Homing Behavior; Desert Climate
PubMed: 36494572
DOI: 10.1007/s00359-022-01600-y