Chemical Ecology

by

André Kessler

• LAST REVIEWED: 31 August 2021
• LAST MODIFIED: 23 May 2012
• DOI: 10.1093/obo/9780199830060-0023

Introduction

“Ours is a world of sights and sounds. We live by our eyes and ears and tend generally to be oblivious to the chemical happenings in our surrounds. Such happenings are ubiquitous. All organisms engender chemical signals, and all, in their respective ways, respond to the chemical emissions of others. The result is a vast communicative interplay, fundamental to the fabric of life” (Eisner and Meinwald 1995, p. v), cited under General Overviews). Chemical ecology is the study of ecological interactions between organisms mediated by chemicals produced by those organisms. Chemical interactions between organisms can be analyzed across all organizational levels, reaching from cell-cell interaction and intraspecific and multitrophic-level interactions to whole community interactions and environmental ecological processes. Because of their ubiquity, chemical signals that carry information (semiochemicals) can be categorized by the types of ecological interactions they mediate, such as intraspecific social communication, antagonistic interactions, and mutualism. Accordingly, this article is organized into three core areas, one formed by the chemicals mediating interactions between members of the same species (pheromones), and the others by interspecific interactions involving allomones (where the sender benefits), and synomones (where both sender and receivers benefit). A fourth group of signals, kairomones (where the receiver benefits), can comprise all other signal categories when they are perceived and utilized by a third organism that itself gains a benefit from eavesdropping on communication between others. While primary studies in chemical ecology focused on the identification of compounds mediating interactions between organisms, today’s debates are dominated by micro- and macroevolutionary aspects of chemical interactions. The very rapid growth of the chemical ecology literature over recent decades has been, in part, driven by the growing appreciation of the high economic value of understanding chemical communication, reaching from applications in pest management over the control of disease vectors in agriculture to the use of chemical signals in medicine. Moreover, the field has dramatically profited from innovations in analytical chemistry, making the separation of complex compound mixtures as well as the identification of compound structures efficient and accessible to a broader community of researchers. Recent advances in molecular ecology have aided an even more rapid mechanistic and functional analysis of semiochemicals, leading to a modern consolidation of different research fields. This collection of significant publications focuses on the functional and evolutionary analysis of chemical signals important in mediating ecological interactions. Moreover, attention has been given to publications that provide conceptual frameworks and are among the most highly cited in the respective subdisciplines. They can thus provide a good introduction for the interested reader and allow efficient forward and backward searching for more detailed information.

General Overviews

The field of chemical ecology as such is relatively young, but it has experienced a very rapid growth in the past few decades, primarily fueled by more readily available chemical analytical and molecular methods. This, on one hand, explains the limited number of concise textbooks in this field, but on the other hand, it also explains the increasing impact and explanatory power chemical ecology has in almost all fields of ecology, evolutionary biology, and biochemistry. In general, there are a number of very good summaries of the chemical ecology of particular groups of organisms, such as algae (Amsler 2008), insects (Roitberg and Isman 1992, Cardé and Miller 2004), crustaceans (Breithaupt and Thiel 2011), and vertebrates (Müller-Schwarze 2006) but a conceptional consolidation of the field of chemical ecology has rarely been undertaken. Sondheimer, et al. 1970 was one of the first comprehensive collections of studies of chemically mediated interactions by the pioneers in the field, and it was updated by another collection of studies, Eisner and Meinwald 1995. The coevolutionary aspects of chemical communication has always been a major concern of the field, and it is nicely summarized in Spencer 1988. Harborne 1993 was one of the first textbooks to reach a broader audience of students. The textbooks and collections of articles cited in this section either provide a general overview or focus on the chemical ecology of particular groups of organisms, while also allowing the extraction of the principal and generally applicable concepts.

• Amsler, Charles D., ed. 2008. Algal chemical ecology. Berlin and London: Springer.

  DOI: 10.1007/978-3-540-74181-7

  This is a collection of articles on the chemical ecology of algae in general, and on the role of defense compound production in different regions and habitats, as well as in mediating algal stress responses such as oxidative burst and herbivore offense. The book covers algal chemical ecology of both freshwater and marine habitats.

• Breithaupt, Thomas, and Martin Thiel. 2011. Chemical communication in crustaceans. New York: Springer Verlag.

  DOI: 10.1007/978-0-387-77101-4

  This collection of articles by specialists in the field of Crustacean chemical communication provides an almost complete overview of the chemical sensory world of crustaceans, covering the entire spectrum of levels of study from sensory physiology to ecology, and discussing potential applications of crustacean chemical ecology in nature conservancy and cultivation.

• Cardé, Ring T., and Jocelyn G. Millar, eds. 2004. Advances in insect chemical ecology. Cambridge, UK: Cambridge Univ. Press.

  DOI: 10.1017/CBO9780511542664

  A collection of articles considering how plants use chemicals to interact with insects.

• Eisner, Thomas, and Jerrold Meinwald, eds. 1995. Chemical ecology: The chemistry of biotic interaction. Washington: National Academy Press.

  A collection of articles providing a broad overview of the major research areas in chemical ecology.

• Harborne, J. B. 1993. Introduction to ecological biochemistry. 4th ed. London: Academic Press.

  A textbook that describes many aspects of biochemical interactions between plants and insects in a didactically immaculate way.

• Müller-Schwarze, Dietland. 2006. Chemical ecology of vertebrates. Cambridge, UK: Cambridge Univ. Press.

  DOI: 10.1017/CBO9780511607233

  The first comprehensive textbook that entirely focuses on vertebrate chemical ecology. It covers all four areas of chemical interaction, through pheromones, synomones, kairomones and allomones.

• Roitberg, Bernard D., and Murray B. Isman, eds. 1992. Insect chemical ecology: An evolutionary approach. New York: Chapman & Hall.

  A collection of articles that provides a comprehensive view on how natural selection may shape insect chemical interactions with their biotic environment.

• Sondheimer, E. H., John B. Simeone, and John Tyler Bonner. 1970. Chemical ecology. New York: Academic Press.

  This book was the first concise introduction into the new field of chemical ecology and was based on a lecture series taught at Syracuse University. It provides basic terminology and a theoretical framework for the then newly formed field.

• Spencer, Kevin C., ed. 1988. Chemical mediation of coevolution. San Diego, CA: Academic Press.

  A collection of articles discussing the coevolutionary processes that affect the chemical ecology of plant-insect interactions.