Chemical Communication in Lobsters [chapter]

Juan Aggio, Charles D. Derby
2010 Chemical Communication in Crustaceans  
Lobsters are fascinating animals that use chemicals as messages regarding their sexual status, their standing in a social hierarchy, and whether they affiliate with or avoid conspecifics. This, plus their economic importance, makes them important models for the study of intraspecific chemical communication. Our chapter is an overview of these processes, including the types of interactions between lobsters influenced by chemicals, how those interactions are affected by chemicals, and how these
more » ... ls, and how these chemicals are detected. Since "lobster" refers to a common body plan rather than a taxonomic group and thus includes animals of differing phylogenetic relatedness and lifestyles -most notably clawed lobsters, spiny lobsters, and slipper lobsters, their use of chemicals in intraspecific interactions is diverse. Whenever possible, we compare the different groups of lobsters, though the amount of data available for relevant behaviors varies with the lifestyle of lobsters. Clawed lobsters use urinary chemicals processed by the olfactory pathway to identify previous opponents and maintain a stable social order, which is important because only the most dominant males will mate. After a hierarchy has been established by fighting, subsequent rematches are shorter and less violent, with urinary chemicals playing a key role in this process. Mate choice and mating behavior are also mediated by urinary olfactory cues. These behaviors are disrupted when one of the animals either has a compromised olfactory sense or is not allowed to release urine. Although there is less available data, the picture seems similar in spiny lobsters, with females using urinary chemicals from males as one of the cues in mate selection. Both spiny and slipper lobsters form dominance hierarchies, but little is known about how they are influenced by chemical signals. Conversely, spiny lobsters have been extensively studied regarding the mechanisms of aggregation and avoidance. Aggregation is mediated by urine-borne chemicals and avoidance is mediated by blood-borne chemicals, both processed by the olfactory system. Molecular identification of these compounds will be critical in allowing researchers to study the neural processing of intraspecific chemicals. Because of their abundance, size, tastiness, and accessibility, lobsters are appreciated by all who enjoy a good seafood meal, are important in the fisheries of many countries, and are well known by most people throughout the world. Lobsters are also well known to scientists because they have been frequently used as models for the study of, among other things, the chemical senses, including the role of chemicals in mediating intraspecific behavior. Much is known about how lobsters use their chemical senses to find or avoid each other, recognize individuals, mate, and battle. Unfortunately, the chemical identities of most of the compounds driving these behaviors are unknown, which has limited the types of studies that can be done and our current understanding of lobsters' chemical ecology. Nevertheless, chemical communication among lobsters is a fascinating topic that is being investigated in many laboratories worldwide. In this chapter, we review the ways whereby lobsters chemically communicate with each other and the contexts in which they do it. We make a distinction between different types of chemicals. Based on the terminology of Wyatt (Chap. 2), we use "semiochemicals" as chemicals involved in animal interactions and "pheromones" as a subset of semiochemicals used in intraspecific contexts. We also use "cues" as chemicals that benefit the receiver and not necessarily the sender, with a prime example being alarm cues released in the blood of injured conspecifics. 12 Chemical Communication in Lobsters 241
doi:10.1007/978-0-387-77101-4_12 fatcat:pjcxeno7ejgvhg7bhywjh5zxfu