Subjects and housing

Our subjects were 27 adult ring-tailed lemurs (17 males, 10 females; mean ± standard error or s.e. age at the time of study: 7.61 ± 0.53 yrs, range: 1.8–25.5 yrs). Of these, 23 (13 males and 10 females) provided genital secretion samples, collected between 2007–2016 (Table 2), and nine males served as focal subjects in behavioural bioassays, conducted in 2016 (see sections on sample collection and behavioural bioassays, below). All of the subjects were captive-born and housed socially at the Duke Lemur Center (DLC; Durham, NC, USA)^43,56. The animals’ social housing conditions allow for exposure to conspecific visual, auditory and olfactory cues, as well as for naturally occurring interactions, including those of aggression and their subsequent injuries (see injury section, below)^48,56,60. Most subjects are semi-free ranging, with access both to forested outdoor enclosures (3–7 ha) and to temperature-controlled, indoor areas. A minority of subjects are housed indoors year-round. All of the animals are provided with a mixed diet of commercial primate chow, fruit, vegetables, fresh browse, and water^56,60. Our research protocols (Protocol Registry Numbers A232–06–07, A171-09-06, A143-12-05 and A111-16-05) abided by the regulations of the United States Department of Agriculture and were approved by the Institutional Animal Care and Use Committee of Duke University. The DLC is fully accredited by the American Association for the Accreditation of Laboratory Animal Care; information on the DLC’s conservation, education and research mission is available at http://lemur.duke.edu/.

Number of unique injury events, involving three phases, that are represented by odorant samples collected from adult ring-tailed lemurs at the Duke Lemur Center, from 2007–2016.

Shown in parentheses are the numbers of samples used for gas chromatography-mass spectrometry (GC-MS) and behavioural bioassays, respectively. These samples were obtained at one time point during each uninjured phase (pre-injury and recovery), but at one or more time points during each injury phase.