Hayakawa Tomohiro, Dobata Shigeto, Matsuno Fumitoshi
Mechatronics-Lab, Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
J Theor Biol. 2020 May 7;492:110186. doi: 10.1016/j.jtbi.2020.110186. Epub 2020 Feb 4.
Self-organizing biological systems, such as colonies of social insects, are characterized by their decentralized control and flexible responses to changing environments, often likened to swarm intelligence. Although decentralized control is well known to be a product of local interactions among agents, without the need for a bird's-eye view, indirect knowledge of properties that indicate the current states of the entire system also helps each agent to respond to changes, thereby leading to a more adaptive system. In this study, we analyze the rules that govern workers' behavioral responses to colony-level properties and assess whether they contribute to adaptive flexibility in social insect colonies. We focus on task allocation among red harvester ants (Pogonomyrmex barbatus) as a model system and develop an ordinary differential equation model to describe the system of task allocation among workers. We simulate 12 scenarios specifying how workers respond to changes in the colony-level properties of colony size and nutritional state. We found that when workers decrease their contact rates in response to increasing colony size, they enable achievement of a larger colony size, similar to that of P. barbatus colonies in nature, and when workers increase their foraging levels in response to decreasing colony-wide nutritional levels, they increase resilience to environmental disturbances. These negative feedback rules governing the response to colony-level properties are consistent with previous reports on ants and honeybees.
自组织生物系统，如群居昆虫群落，其特点是分散控制以及对不断变化的环境具有灵活反应，常被比作群体智能。尽管众所周知，分散控制是个体间局部相互作用的产物，无需全局视角，但对指示整个系统当前状态的属性的间接了解也有助于每个个体对变化做出反应，从而形成一个更具适应性的系统。在本研究中，我们分析了支配工蚁对群落水平属性行为反应的规则，并评估它们是否有助于群居昆虫群落的适应性灵活性。我们将红收获蚁（Pogonomyrmex barbatus）的任务分配作为一个模型系统进行研究，并开发了一个常微分方程模型来描述工蚁间的任务分配系统。我们模拟了12种情景，具体说明了工蚁如何对群落大小和营养状态等群落水平属性的变化做出反应。我们发现，当工蚁随着群落规模的增加而降低其接触率时，它们能够实现更大的群落规模，类似于自然界中的红收获蚁群落；当工蚁随着全群落营养水平的下降而提高其觅食水平时，它们会增强对环境干扰的恢复力。这些支配对群落水平属性反应的负反馈规则与先前关于蚂蚁和蜜蜂的报道一致。
