Exploration and exploitation of food sources by social insect colonies: a revision of the scout-recruit concept

Abstract

Social insect colonies need to explore and exploit multiple food sources simultaneously and efficiently. At the individual level, this colony-level behaviour has been thought to be taken care of by two types of individual: scouts that independently search for food, and recruits that are directed by nest mates to a food source. However, recent analyses show that this strict division of labour between scouts and recruits is untenable. Therefore, a modified concept is presented here that comprises the possible behavioural states of an individual forager (novice forager, scout, recruit, employed forager, unemployed experienced forager, inspector and reactivated forager) and the transitions between them. The available empirical data are reviewed in the light of both the old and the new concept, and probabilities for the different transitions are derived for the case of the honey-bee. The modified concept distinguishes three types of foragers that may be involved in the exploration behaviour of the colony: novice bees that become scouts, unemployed experienced bees that scout, and lost recruits, i.e. bees that discover a food source other than the one to which they were directed to by their nest mates. An advantage of the modified concept is that it allows for a better comparison of studies investigating the different roles performed by social insect foragers during their individual foraging histories.

Exploring the Bee Hive Metaphor as a Model for Problem Solving: Search, Optimisation, and More

“…We again found inspiration in nature (Biesmeijer, 2001) and in the failed follower hypothesis (Beekman, 2007). The foraging bees fall within one of two categories -scouts or recruits.…”

Effect of Citrus floral extracts on the foraging behavior of the stingless bee Scaptotrigona pectoralis (Dalla Torre)

“…It might be then that the bees in our experimental setup needed more time to switch to the control patch or a decrease of the food profitability happen as it is proposed by Schmidt et al (2006). Switching to a new food source requires that foragers turn idle, receptive to be reactivated by successful foragers (Biesmeijer & de Vries 2001) in our case, the foragers in the control patch. For pollination purposes this might mean a delay in pollen transfer between trees; but as long as foragers are spread over several food sources, there is the chance of switching and of pollen transfer between individual plants.…”

Comparative brain transcriptomic analyses of scouting across distinct behavioural and ecological contexts in honeybees

“…Because of the big differences in ecological and behavioural contexts between the two types of scouts, we compared each type of scout to the relevant group of 'recruits', those bees who followed the information provided by the scouts in each context [21]. Recruits are similar to scouts in age, experience, search image and activity level during foraging and nest hunting, but differ significantly in their novelty-seeking tendency.…”