Individual precocity, temporal persistence, and task-specialization of hygienic bees from selected colonies of Apis mellifera

Abstract

A b s t r a c t Hygienic behaviour is a complex trait that gives Apis mellifera L. resistance against brood diseases. Variability in the expression of hygienic behaviour is evidenced at the colonylevel and is explained by the proportion and propensity of individual worker bees that engage in hygienic activities. We investigated the temporal performance and the dynamics of task-specialisation of individual bees over time, both in selected hygienic (H) and non-hygienic (NH) colonies. Then we evaluated the impact of these behavioural aspects on the colony performance. Bees that perform hygienic behaviour (hygienic bees) in our H colonies were more persistent in the hygienic activities throughout the days of the investigation. Such bees were more efficient in the removal of pin-killed brood than hygienic bees in the NH colonies. Hygienic bees in the H colonies were also specialist in the sub-tasks involved in the detection of odour stimulus from dead brood and continued to perform these activities throughout the days of the investigation (temporal persistence). Age-distribution of hygienic bees in the H colonies was asymmetrical, with a larger proportion of these bees performing hygienic activities early in life. At a colony-level, H showed higher efficiency compared to the NH colonies. The present results highlight the fact that individual behaviour may influence the collective dynamics of the hygienic behaviour in honeybee colonies. The results also note that the selection for highly hygienic colonies would result in changes in individual bees that improve the performance of the behaviour at the colony level. The relevance of task-partitioning and age-specialisation of hygienic bees on social immunity is discussed.

Parallel evolution ofVarroaresistance in honey bees: a common mechanism across continents?

“…Variability is also likely due to temporal changes in the composition of the different hygienic workers. To elaborate, the three main stages of brood removal (the initial detection and opening of the cell cap, the full uncapping of the cell and finally removing or cannibalizing the pupae or recapping the cell [124]) are conducted by bees of different ages and sensory acuity, a division of labour further affected by genetic, neural, social and environmental conditions [55,[125][126][127][128]. For example, an imbalance of 'uncapper' versus 'recapper' bees may cause many brood cells to be left open [55].…”

Hygienic Behavior of Apis mellifera and Its Relationship with Varroa destructor Infestation and Honey Production in the Central Highlands of Ecuador

“…However, the variability in the expression of this trait depends on the aptitude or composition of the colonies. It might be due to the distribution of workers to different tasks [37]. Similarly, in evaluations conducted in two different years, a wide range of variations was attributed to seasonal changes [38].…”

APIS MELLIFERA EN EL ALTIPLANO CENTRAL DEL ECUADOR: africanización, Varroa destructor, caracteres conductuales y producción melífera

“…Resultados coincidentes reportaron Boutin et al, (2015), quienes después de realizar dos evaluaciones en años diferentes, indicaron un amplio rango de variación atribuible a la diferencia de estaciones. Sin embargo, el hecho de que las colonias muestren variabilidad para la expresión de este rasgo, se les atribuirá a la fuerte aptitud física o a una composición óptima de colonias, que se basa en la distribución de los obreras a diversas tareas (Scannapieco et al, 2016). Se encontraron los mejores porcentajes de higiene en el primer muestreo, en las colonias ubicadas en el primer piso…”