Short-Term Activity Cycles in Leptothorax Ants

行为研究中的一个基本问题是社会行为的复杂性是从社会单位内的个人行为中产生的。如果一个社会群体的特征可以用个人行为的总和来解释，那么社会行为就是个人行为的结果。如果一个群体的特征不是简单地由于个体的行动总和，那么社会行为就具有突现性。众所周知，群居昆虫具有群体的特性，而这些特性在组成群体的个体中并不存在。一个群体的活动是它所有其他行为的基础。科尔博士发现，一种叫异卵细胸蚁（Leptothorax allardycei）的蚂蚁巢穴内的活动具有短期周期，活动的脉冲间隔约为20分钟。单独的、孤立的蚂蚁并没有表现出这种规律性的活动，但随着越来越多的蚂蚁加入到群体中，这种周期性就出现了。本研究项目的目的是从个体蚂蚁的行为和运动模式来分析蚁群中周期性的产生。科尔博士将开发一个蚂蚁个体运动模式的计算机模型，包括它们的运动速度、转弯角度和在蚁巢中的位置。这些信息将与它们对遇到其他蚂蚁的反应、遇到对单个蚂蚁后续活动概率的影响以及活动的相互同步等信息相结合，以产生一个群体活动的计算机模型。该模型将通过使用报警信息素直接操纵菌落的活动来进行测试。科尔博士的研究是朝着理解社会单位中的个体产生社会现象的机制迈出的重要一步。在我们了解社会互动的机制之前，预测群体生活的后果和自然选择对社会行为的影响仍然是不可能的。

A fundamental problem in the study of behavior is the emergence of complexity of social behavior from the behavior of individuals within the social unit. If the characteristics of a social group can be accounted for by the summed actions of individuals, then social behavior is a resultant of individual behavior. If the characteristics of a group are not simply due to the summed actions of individuals, then social behavior has an emergent property. Social insects are well known to have attributes of the colony that are not present among the individuals comprising the colony. The activity of a colony is basic to all its other behavior. Dr. Cole has discovered that activity within nests of a species of ant, Leptothorax allardycei, has short-term cycles, with pulses of activity occurring at intervals of approximately 20 minutes. Individual, isolated ants do not show this regularity of activity, but the periodicity emerges as more and more ants are added to the aggregate. The purpose of this research project is to analyze the production of periodicity in colonies from the behavior and movement patterns of individual ants. Dr. Cole will develop a computer model of the movement patterns of individual ants, including their velocity of movement, turning angles, and position within the nest that they occupy. This information will be combined with information on their response to encounters with other ants, the effect of an encounter on the probability of subsequent activity by an individual ant, and mutual synchronization of activity to produce a computer model of the activity of a colony. This model will be tested by direct manipulation of the activity of colonies through the use of alarm pheromones. Dr. Cole's research is an important step toward gaining an understanding of the mechanisms by which the individuals within a social unit produce social phenomena. Until we understand the mechanisms of social interaction, it will remain impossible to predict the consequences of group living and the effects of natural selection on social behavior.