Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.
Department of Biology, Bishop's University, Sherbrooke, QC, Canada.
Sci Rep. 2018 Jun 29;8(1):9882. doi: 10.1038/s41598-018-27322-3.
Honesty is crucial in animal communication when signallers are conveying information about their condition. Condition dependence implies a cost to signal production; yet, evidence of such cost is scarce. We examined the effects of naturally occurring injury on the quality and salience of olfactory signals in ring-tailed lemurs (Lemur catta). Over a decade, we collected genital secretions from 23 (13 male, 10 female) adults across 34 unique injuries, owing primarily to intra-group fights. Using gas chromatography-mass spectrometry, we tested for differences in the chemical composition of secretions across pre-injury, injury and recovery, in animals that did and did not receive antibiotics. Lemur genital secretions were significantly dampened and altered during injury, with patterns of change varying by sex, season and antibiotics. Using behavioural bioassays (excluding odorants from antibiotic-treated animals), we showed that male 'recipients' discriminated injury status based on scent alone, directing more competitive counter marking towards odorants from injured vs. uninjured male 'signallers.' That injured animals could not maintain their normal signatures provides rare evidence of the energetic cost to signal production. That conspecifics detected olfactory-encoded 'weakness' suggests added behavioural costs: By influencing the likelihood of intra- or inter-sexual conflict, condition-dependent signals could have important implications for socio-reproductive behaviour.
在动物交流中，当信号传递者传达有关其自身状况的信息时，诚实至关重要。状况依赖性意味着信号产生会带来成本；然而，这种成本的证据很少。我们研究了自然发生的伤害对环尾狐猴（Lemur catta）的嗅觉信号的质量和显著性的影响。在十多年的时间里，我们从 34 个不同的伤口中收集了 23 只（13 只雄性，10 只雌性）成年个体的生殖器分泌物，这些伤口主要是由于群体内部的争斗造成的。我们使用气相色谱-质谱联用技术，在接受和不接受抗生素的动物中，检测了生殖器分泌物在受伤前、受伤中和恢复期的化学成分差异。环尾狐猴的生殖器分泌物在受伤期间明显减弱和改变，变化模式因性别、季节和抗生素而异。通过行为生物测定（排除来自接受抗生素治疗的动物的气味），我们表明，雄性“接受者”仅根据气味就能区分受伤状态，将更多的竞争性反击标记指向来自受伤雄性“信号发送者”的气味。受伤的动物无法保持其正常特征，这为信号产生的能量成本提供了罕见的证据。同种动物检测到嗅觉编码的“弱点”表明存在额外的行为成本：通过影响内部或外部性别冲突的可能性，状况依赖性信号可能对社会生殖行为有重要影响。
