Mechanisms of Chemical Communication

该项目的总体目标是了解动物通过气味的个体识别，并最终将其作为理解大脑嗅觉系统功能组织以及社会记忆方面的一种方式。在这个项目中，约翰斯顿博士将研究动物是如何通过气味进行交流的。特别是，他将研究一种被称为气味过度标记的现象，在这种现象中，一种动物将其气味储存在与另一种动物相同的地方。初步结果表明，通过这样做，一只动物可以掩盖另一只动物先前留下的气味信息，这表明过度标记具有竞争功能。约翰斯顿博士将利用金仓鼠进行各种行为测试，试图(1)证明过度标记在动物社会生活中的竞争功能；(2)描述允许动物从已被几个个体标记的地方破译信息的特殊感知机制；(3)研究动物如何利用这些标记中的个体信息来指导它们的社会行为。这些实验至少对三个科学领域具有重要意义，并且可能也有一些实际意义。首先，嗅觉交流和气味标记在大多数哺乳动物、少数鸟类、大多数爬行动物、一些两栖动物和大量无脊椎动物的生活中很重要，但我们对它仍然知之甚少。这项研究对动物如何利用气味进行相互交流，从而调节它们的社会互动提供了全新的见解。这一新知识将帮助我们理解领地、主从互动、配偶选择和配偶竞争以及社会认可等行为的各个方面。因此，它最终可能对如何更好地在实验室和动物园圈养动物，或在家庭中管理它们的行为有实际意义，甚至可能有助于野生动物管理。其次，这些实验应该给我们提供关于嗅觉的新见解，通过描述迄今为止未被怀疑的感官知觉能力，动物可以从两个或更多个体的复杂气味混合物中提取关于一个个体的信息。第三，这些实验将提供新的知识和新的行为范式，可以作为研究嗅觉和更一般的过程（如个体识别和记忆）背后的大脑机制的模型。

The general goals of this project are to understand individual recognition by scent in animals and, eventually, to use this as a way to understand the functional organization of the olfactory system in the brain as well as aspects of social memory. In this project, Dr. Johnston will investigate how animals communicate by scent. In particular, he will study a phenomenon known as scent over-marking, in which one animal deposits its scent in the same places as another. Preliminary results suggest that, by doing so, one animal can mask the information in scent deposited previously by another individual, suggesting that over-marking has competitive functions. Using golden hamsters in a variety of behavioral tests, Dr. Johnston will attempt to (1) document such competitive functions of over-marking in the social lives of animals, (2) characterize the special perceptual mechanisms that allow animals to decipher information from places that have been marked by several individuals, and (3) investigate how animals use information about individuals in such marks to guide their social behavior. These experiments have importance for at least three domains of science, and may have some practical implications as well. First, olfactory communication and scent-marking are important in the lives of most mammals, a few birds, most reptiles, some amphibians, and a huge number of invertebrates, yet we still understand little about it. This research promises entirely new insights into how animals use scent to communicate with one another and thus to regulate their social interactions. This new knowledge would help us to understand such aspects of behavior as territoriality, dominant-subordinate interactions, mate choice and competition for mates, and social recognition. Thus, it could eventually have practical implications for how to better house animals in captivity in labs and zoos, or to manage their behavior in households, and could even be helpful in wildlife management. Second, these experiments should give us new insights into the sense of smell by characterizing heretofore unsuspected sensory-perceptual abilities by which animals can extract information about one individual from complex mixtures of scent from two or more individuals. Third, the experiments will provide new knowledge and new behavioral paradigms that can be used as models for investigating the brain mechanisms underlying both the sense of smell and more general processes such as individual recognition and memory.