Almeidaetal.revised.xlsx

This study examines whether rock cavies (Kerodon rupestris), which are social rodents, modulate their alarm calls in response to various threat contexts. Conducted across four sample areas within two study sites in the Brazilian Caatinga region, alarm calls were collected using the ad libitum method. The acoustic responses of free-ranging rock cavies were then analyzed using discriminant function analysis, principal component analysis, and generalized mixed linear models to classify vocal types and assess differences in vocalization rates and acoustic parameters. The findings reveal that rock cavies produce both slow and fast alarm whistles in response to threats. Fast alarm whistles, emitted exclusively in response to nearby ocelots (Leopardus pardalis), exhibited a lower pitch (F1, 26.81=22.15, P<0.001), shorter duration (F1, 28.66=30.08, P<0.001), and shorter pulse intervals (F1, 29.30=9.95, P=0.004) compared to the slow alarm whistles. Slow alarm whistles were produced when rock cavies were threatened by distant ocelots, as well as by both distant and closer humans, dogs (Canis familiaris), marmosets (Callithrix spp.), tayras (Eira barbara), and birds of prey (Caracara plancus). The type of threat influenced the number of pulses (F6, 20.76=3.60, P=0.013) and pulse intervals (F6, 12.20=11.57, P<0.001) of slow alarm whistles. Rock cavies produced more pulses when threatened by dogs and birds of prey compared to humans (P<0.05) and shorter pulse intervals when threatened by ocelots compared to humans and dogs (P<0.05). Additionally, lower-pitched slow alarm whistles (F1, 19.84=7.46, P=0.013) with shorter pulse intervals (F1, 21.02=17.04, P<0.001) were emitted when threats were nearby compared to more distant threats. This study highlights the influence of various threats and their proximity on the modulation of rock cavy alarm calls, showcasing their behavioral adaptability. This crucial survival strategy not only enhances our understanding of rock cavies’ behavior but also has the potential to inspire research in other species and ecological contexts.

本研究旨在探究群居啮齿类动物岩豚鼠（Kerodon rupestris）是否会根据不同威胁情境调控其报警叫声。研究于巴西卡廷加（Caatinga）区域内两个研究地点的四个采样区域开展，采用任意取样法（ad libitum method）采集报警叫声样本。随后，通过判别函数分析、主成分分析以及广义线性混合模型，对自由活动岩豚鼠的声学响应进行分析，以对其鸣叫声类型进行分类，并评估鸣叫声频次与声学参数的差异。研究结果显示，岩豚鼠会针对威胁发出慢速与快速两类报警哨声。快速报警哨声仅在应对近距离虎猫（Leopardus pardalis）威胁时发出，与慢速报警哨声相比，其音调更低（F₁,₂₆.₈₁=22.15, P<0.001）、持续时长更短（F₁,₂₈.₆₆=30.08, P<0.001）且脉冲间隔更短（F₁,₂₉.₃₀=9.95, P=0.004）。慢速报警哨声则在岩豚鼠遭遇远距离虎猫，以及远距离、近距离的人类、家犬（Canis familiaris）、狨猴（Callithrix spp.）、美洲獭猫（Eira barbara）和猛禽（Caracara plancus）威胁时发出。威胁类型会影响慢速报警哨声的脉冲数量（F₆,₂₀.₇₆=3.60, P=0.013）与脉冲间隔（F₆,₁₂.₂₀=11.57, P<0.001）：当遭遇家犬与猛禽威胁时，岩豚鼠发出的脉冲数量多于遭遇人类威胁时（P<0.05）；而遭遇虎猫威胁时，其脉冲间隔短于遭遇人类与家犬威胁时（P<0.05）。此外，当威胁距离更近时，岩豚鼠会发出音调更低（F₁,₁₉.₈₄=7.46, P=0.013）且脉冲间隔更短（F₁,₂₁.₀₂=17.04, P<0.001）的慢速报警哨声。本研究阐明了各类威胁及其距离对岩豚鼠报警叫声调控的影响，展现了其行为适应性。这一关键的生存策略不仅加深了我们对岩豚鼠行为的认知，还有望为其他物种及生态场景下的相关研究提供启发。