Sensory ecology is a relatively new field focusing on the information organisms obtain about their environment. It includes questions of what information is obtained, how it is obtained (the mechanism), and why the information is useful to the organism (the function). Sensory ecology is the study of how organisms acquire, process, and respond to information from their environment. All individual organisms interact with their environment (consisting of both animate and inanimate components), and exchange materials, energy, and sensory information. Ecology has generally focused on the exchanges of matter and energy, while sensory interactions have generally been studied as influences on behavior and functions of certain physiological systems (sense organs). The relatively new area of sensory ecology has emerged as more researchers focus on questions concerning information in the environment. This field covers topics ranging from the neurobiological mechanisms of sensory systems to the behavioral patterns employed in the acquisition of sensory information to the role of sensory ecology in larger evolutionary processes such as speciation and reproductive isolation. While human perception is largely visual, other species may rely more heavily on different senses. In fact, how organisms perceive and filter information from their environment varies widely. Organisms experience different perceptual worlds, also known as “umwelten”, as a result of their sensory filters. These senses range from smell (olfaction), taste (gustation), hearing (mechanoreception), and sight (vision) to pheromone detection, pain detection (nociception), electroreception and magnetoreception. Because different species rely on different senses, sensory ecologists seek to understand which environmental and sensory cues are more important in determining the behavioral patterns of certain species. In recent years, this information has been widely applied in conservation and management fields. Reactions of organisms to environmental changes Noise level changes Communication is the key to many species interactions. In particular, many species rely on vocalizations for information such as potential mates, nearby predators, or food availability. Human changes in the habitat modify acoustic environments and may make it more difficult for animals to communicate. Humans may alter acoustic environments by modifying background noise levels, modifying habitat, or changing species composition. These changes in acoustic environments can mask the vocalizations of various species. Because humans can exert such strong changes on acoustic environments, sensory ecologists have been particularly interested in researching and understanding how organisms react to these changes. Anthropogenic changes to acoustic environments have had perhaps the most significant impacts on species that rely on