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In recent years, an increasing number of studies have focused on exploring the principles and mechanisms underlying the emergence of collective intelligence in biological populations, aiming to provide insights for human society and the engineering field. Pigeon flock behavior garners significant attention as a subject of study. Collective homing flight is a commonly observed behavioral pattern in pigeon flocks. The study analyzes GPS data during the homing process and utilizes acceleration information, which better reflects the flock's movement tendencies during turns, to describe the leadership relationships within the group. By examining the evolution of acceleration during turning, the study unveils a dynamic leadership mechanism before and after turns, employing a more intricate dynamic model to depict the flock's motion. Specifically, during stable flight, pigeon flocks tend to rely on fixed leaders to guide homing flight, whereas during turns, individuals positioned in the direction of the flock's turn experience a notable increase in their leadership status. These findings suggest the existence of a dynamic leadership mechanism within pigeon flocks, enabling adaptability and stability under diverse flight conditions. From an engineering perspective, this leadership mechanism may offer novel insights for coordinating industrial multi-robot systems and controlling drone formations. [ABSTRACT FROM AUTHOR]

Wind energy is considered as one of the most promising renewable energy sources. However the growth in wind farms over the last few years raises questions about the possible effects on ecosystems. The widely documented impacts on birds and bats have garnered much attention. On the other hand, few studies exist concerning the impact on insects, and notably pollinators, despite the essential pollination services they provide for food production and plant biodiversity. We evaluated the effects of wind turbines on the honey bee via young mated queen egg-laying activity, colony weight gain, and bee behavior at the colony level, and on the homing ability of foragers at the individual level. Our results did not show an impact of wind turbines on forager mortality or on the reproductive caste during mating flights, nor an alteration of the orientation of foragers returning to the hive. We also did not observe a disruptive effect on the behavior, development or functioning of the colonies. Our results, under the described experimental conditions, reveal new information that would support an absence of impact of wind turbines on honey bee colonies. [ABSTRACT FROM AUTHOR]

Abstract The paradigm for all toxicological bioassays in the risk assessment of pesticide registration reflects the principle that experimental conditions should be controlled to avoid any other factors that may affect the endpoint measures. As honeybee colonies can be frequently exposed to bio-aggressors in real conditions, often concomitantly with pesticides, co-exposure to pesticide/bio-aggressors is becoming a concern for regulatory authorities. We investigated the effects of the neonicotinoid insecticide thiamethoxam on the homing performances of foragers emerging from colonies differentiated by health status (infestation with Varroa destructor mites, microsporidian parasite Nosema spp. and Deformed Wing Virus). We designed a homing test that has been recently identified to fill a regulatory gap in the field evaluations of sublethal doses of pesticides before their registration. We also assessed the effect of temperature as an environmental factor. Our results showed that the Varroa mite exacerbates homing failure (HF) caused by the insecticide, whereas high temperatures reduce insecticide-induced HF. Through an analytical Effective Dose (ED) approach, predictive modeling results showed that, for instance, ED level of an uninfested colony, can be divided by 3.3 when the colony is infested by 5 Varroa mites per 100 bees and at a temperature of 24 °C. Our results suggest that the health status of honeybee colonies and climatic context should be targeted for a thorough risk assessment. Graphical abstract Image 1 Highlights • Temperature and colony health modulate insecticide-induced homing failure in honeybee. • Varroa mites exacerbate homing failure caused by the insecticide thiamethoxam. • Low temperatures aggravate insecticide-induced homing failure. • Pesticide risk assessment should include temperature and Varroa mites as covariates. [ABSTRACT FROM AUTHOR]