title: Dung odours signal sex, age, territorial and oestrous state in white rhinos.
abstract: Mammals commonly communicate olfactorily via urine. However, the extent to which they communicate via dung, another waste product, is unknown. Behavioural studies suggest that mammals can obtain information from dung odours but are unclear about the information transmitted. Moreover, an understanding of the volatile organic compounds (VOCs) released from dung is limited. To address this, we analysed the odours emitted from the dung of free-ranging white rhinos, and found that 2,3-dimethylundecane signalled an individual's sex, heptanal discriminated age class, nonane defined male territorial status and 2,6-dimethylundecane indicated female oestrous state. To validate these findings, we artificially reproduced key elements of the territorial and oestrous odour profiles (i.e. profiles likely to elicit behavioural responses from receivers). We then exposed free-ranging territorial males to these odours. In response, males elicited behaviours associated with the specific odours (e.g. territorial male (potential threat): reduced latency in assuming vigilance; oestrous female (potential mate): increased investigation). These results indicate that the VOCs identified from the dung of free-ranging individuals do transmit key information. Moreover, as white rhinos of all ages and sexes defecate communally, middens probably act as information centres. Furthermore, as many other mammals defecate communally, olfactory communication via dung odours is likely a widespread phenomenon.
authors.affiliation: School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa courtney.marneweck@gmail.com.
authors.forename: Courtney
authors.identifier: 0000-0002-5064-1979
authors.initials: C
authors.lastname: Marneweck
authors.affiliation: Chemical Plant Ecology, Technische Universität Darmstadt, Darmstadt, Germany.
authors.forename: Andreas
authors.identifier: 0000-0002-5288-0498
authors.initials: A
authors.lastname: Jürgens
authors.affiliation: School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa.
authors.forename: Adrian M
authors.identifier: 0000-0002-6451-6132
authors.initials: AM
authors.lastname: Shrader
mesh_terms: D000818:Animals; D004971:Estrus / Q000502:physiology*; D005260:Female; D008297:Male; D009812:Odorants; D010527:Perissodactyla / Q000502:physiology*; D012726:Sexual Behavior, Animal; D013731:Territoriality; D055549:Volatile Organic Compounds
chemical_list: D055549:Volatile Organic Compounds
keywords: Ceratotherium simum; middens; olfactory communication; volatile compounds