title: Reproductive endocrine patterns and volatile urinary compounds of Arctictis binturong: discovering why bearcats smell like popcorn.
abstract: Members of the order Carnivora rely on urinary scent signaling, particularly for communicating about reproductive parameters. Here, we describe reproductive endocrine patterns in relation to urinary olfactory cues in a vulnerable and relatively unknown viverrid--the binturong (Arctictis binturong). Female binturongs are larger than and dominate males, and both sexes engage in glandular and urinary scent marking. Using a large (n = 33), captive population, we collected serum samples to measure circulating sex steroids via enzyme immunoassay and urine samples to assay volatile chemicals via gas chromatography-mass spectrometry. Male binturongs had expectedly greater androgen concentrations than did females but, more unusually, had equal estrogen concentrations, which may be linked to male deference. Males also expressed a significantly richer array of volatile chemical compounds than did females. A subset of these volatile chemicals resisted decay at ambient temperatures, potentially indicating their importance as long-lasting semiochemicals. Among these compounds was 2-acetyl-1-pyrroline (2-AP), which is typically produced at high temperatures by the Maillard reaction and is likely to be responsible for the binturong's characteristic popcorn aroma. 2-AP, the only compound expressed by all of the subjects, was found in greater abundance in males than females and was significantly and positively related to circulating androstenedione concentrations in both sexes. This unusual compound may have a more significant role in mammalian semiochemistry than previously appreciated. Based on these novel data, we suggest that hormonal action and potentially complex chemical reactions mediate communication of the binturong's signature scent and convey information about sex and reproductive state.
authors.affiliation: University Program in Ecology, Duke University, Durham, NC, USA.|Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.
authors.forename: Lydia K
authors.initials: LK
authors.lastname: Greene
authors.affiliation: Department of Chemistry, Hendrix College, Conway, AR, USA.|National Center for Environmental Health, Division of Laboratory Sciences, Clinical Chemistry Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Wallen
authors.affiliation: Carnivore Preservation Trust (now Carolina Tiger Rescue), 1940 Hanks Chapel Road, Pittsboro, North Carolina, 27312, USA.|Denver Zoo, 2300 Steele Street, Denver, Colorado, 80205, USA.
authors.forename: Anneke
authors.initials: A
authors.lastname: Moresco
authors.affiliation: Department of Chemistry, Hendrix College, Conway, AR, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Goodwin
authors.affiliation: University Program in Ecology, Duke University, Durham, NC, USA. cdrea@duke.edu.|Department of Evolutionary Anthropology, Duke University, Durham, NC, USA. cdrea@duke.edu.|Department of Biology, Duke University, Durham, NC, USA. cdrea@duke.edu.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Drea
mesh_terms: D000735:Androstenedione / Q000652:urine; D000819:Animal Communication; D000818:Animals; D004032:Diet; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood; D008297:Male; D009812:Odorants / Q000032:analysis*; D010675:Pheromones / Q000737:chemistry / Q000502:physiology*; D011758:Pyrroles / Q000652:urine*; D012098:Reproduction / Q000502:physiology*; D013696:Temperature; D045949:Viverridae / Q000097:blood / Q000502:physiology* / Q000652:urine; D055549:Volatile Organic Compounds / Q000032:analysis / Q000652:urine
chemical_list: D012739:Gonadal Steroid Hormones; D010675:Pheromones; D011758:Pyrroles; D055549:Volatile Organic Compounds; D000735:Androstenedione; C426303:2-acetyl-1-pyrroline
keywords: 2-Acetyl-1-pyrroline; Female dominance; Olfactory communication; Reproductive endocrinology; Urinary signals; Viverrid