Foraging behavior has been extensively studied in harvester ants (Hymenoptera: Formicidae); however, there is little information about the determinants of foraging success. We developed a path analysis model to quantify the functional relationships among the components of foraging at the colony level (onset, duration, number of foragers) and foraging success. Variation in the onset of foraging ...

Division of labour between reproductive queens and sterile workers is a hallmark of insect societies and an important component of their ecological success (Hölldobler & Wilson, 1990). In ants and other social Hymenoptera forming large and complex societies, reproductive division of labour is generally associated with marked morphological differences between the queen and worker castes. These d...

Many systems in the world are hierarchical and agentbased. These systems have natural higher levels in which agents are composites of lower-level agents and their environment. One example of such a system is a manycolony social insect system, such as those of Harvester Ants (1). At the lower level of description, the agents of the colony are individual ants, which act in their environment. At a...

Colonies of the red harvester ant, Pogonomyrmex barbatus, do various tasks outside the nest. There is a daily temporal pattern in the numbers of ants engaged in each of five activities: foraging, nest maintenance, patrolling, midden work and convening. Perturbations were carried out in the field to investigate how the daily round changes in response to environmental events and colony needs. Int...

Mitosis is a fundamental process for chromosome segregation in all multicellular organisms. Misregulation of mitosis can cause genetic instability and cancer. Thus, identification of the genes involved in the regulation of mitosis is important for understanding the mechanism of chromosome segregation and genome instability. Unbiased genetic screens are powerful tools for identifying new gene fu...

Many spatial patterns observed in nature emerge from local processes and their interactions with the local environment. The clustering of objects by social insects represents such a pattern formation process that can be observed at both the individual and the collective level. In this paper, we study the interaction between air currents and clustering behaviour in order to address the coordinat...

We revise species of seed-harvester ants in the genus Pogonomyrmex (subfamily Myrmicinae) that occur on the Caribbean island of Hispaniola. Three species are recognized: P. aterrimus Wheeler (new status), P. saucius Wheeler and Mann, and P. schmitti Forel. Pogonomyrmex schmitti sublaevigatus Wheeler (= schmitti) and P. schmitti darlingtoni Wheeler (= aterrimus) are synonomized. We also describe...

This paper addresses the issue of applying decentralised task allocation and task switching mechanisms in heterogeneous groups of robots in order to increase their ability to respond to task demand effectively. Our work is strongly inspired by the behaviour of eusocial insects (typically ants) and their behaviour of switching tasks in order to meet the changing demand. The objective of this pap...