Abstract
Unique mixtures of pheromone components are commonly identified in insects, and have been shown to increase attractiveness towards conspecifics when reconstructed at the natural ratio released by the signaler. In previous field studies of pheromones that attract female sea lamprey (Petromyzon marinus, L.), putative components of the male-released mating pheromone included the newly described bile alcohol 3,12-diketo-4,6-petromyzonene-24-sulfate (DkPES) and the well characterized 3-keto petromyzonol sulfate (3kPZS). Here, we show chemical evidence that unequivocally confirms the elucidated structure of DkPES, electrophysiological evidence that each component is independently detected by the olfactory epithelium, and behavioral evidence that mature female sea lamprey prefer artificial nests activated with a mixture that reconstructs the male-released component ratio of 30:1 (3kPZS:DkPES, molar:molar). In addition, we characterize search behavior (sinuosity of swim paths) of females approaching ratio treatment sources. These results suggest unique pheromone ratios may underlie reproductive isolating mechanisms in vertebrates, as well as provide utility in pheromone-integrated control of invasive sea lamprey in the Great Lakes.
Highlights
A common source of conspecific information used in orientation strategies and mate location across the animal kingdom is provided by pheromones, or unique chemical signatures that are released by animals and influence behavior or development of members of the same species [1, 2]
Adult sea lamprey used for electro-olfactogram (EOG) recordings were collected in spring 2012 by commercial fishing companies in Lake Huron and transported to United States Geological Survey and Great Lakes Science Center—Hammond Bay Biological Station (HBBS)
Vice versa, when the epithelium was pre-adapted to DkPES, the EOG response to 3-keto petromyzonol sulfate (3kPZS) was larger than the response to DkPES (Fig 2B, t = -4.68, P = 0.002). These results indicate that the olfactory epithelium distinguished DkPES and 3kPZS by at least two different sets of receptors
Summary
A common source of conspecific information used in orientation strategies and mate location across the animal kingdom is provided by pheromones, or unique chemical signatures that are released by animals and influence behavior or development of members of the same species [1, 2]. The sending and receiving of pheromones result in movement patterns that reduce the distance between conspecifics across their odor landscape (attraction) and/or maintain individuals in place (arrestant) to gain advantage in mating or feeding [2, 3]. Pheromones that function in sex and aggregation are often comprised of multiple components at specific ratios [4,5,6]. For pheromones of unique ratios to function as species-specific attractants, a level of discrimination against individual components must occur at the sensory and behavioral level. Olfactory systems have been shown, via electrophysiological cross-
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
