The ring-tailed lemur has a complex array of distinct vocalizations used to maintain group cohesion during foraging and alert group members to the presence of a predator. The tables below detail calls documented in the wild and studied at the Duke Lemur Center.
+ Adult Affiliative VocalizationsCallVocalizersInferred Function Moan All except infants <14 weeks Promotes group cohesion in low-to-moderate arousal contexts Early-High Wail All except infants <6–8 weeks Promotes group cohesion; indicates moderate-to-high level arousal level of caller Late-High Wail Non-infant females (typically), males (rarely) May promote group cohesion under conditions of extreme arousal Howl Non-infant males Male advertisement call; together with female counter-calling, howls advertise the presence and location of the group Hmm All except infants <5 weeks Indicates that slow group relocation is imminent and promotes group cohesion, or reflects a caller's desire to maintain conspecific contact Huh Infants >3 months (most frequent); male juveniles and adolescents; rarely by adults Similar to hmm, but marks a caller's location more effectively Purr Adult females (most frequent); both sexes of all age classes Appears to express contentment; also may communicate nonaggressive intent of an adult during close contact Chirp All except infants <3 weeks Elicits rapid group movement and may promote group cohesion in this context
+ Adult Agonistic VocalizationsCallVocalizersInferred Function Yip All non-infants, except alpha females Expresses mild fear and, perhaps, willingness to defer to a dominant Cackle Adults of both sexes A defensive display that may reflect a willingness to become aggressive if pressed Squeal Males, during tail waving only Male "status assertion" vocalization Twitter All except infants <6 months Communicates somewhat fearful but nevertheless assertive demeanor Plosive Bark Both sexes of all ages classes High-intensity threat vocalization Chutter Dominant adults (toward subordinates of all ages) Low-to-moderate threat vocalization; may encourage subordinates to give way to dominants, thereby reaffirming dyadic dominance relationships.
+ Alerting & Antipredator VocalizationsCallVocalizersInferred Function Gulp All except infants <14 weeks Generalized "group alert" vocalization Rasp All except infants Aerial predator alarm call Shriek, variant 1 All except infants May serve to inform a raptor that it has been seen, and/or may discourage pursuit by intimidation, as well as to broadcast widely that a low-flying raptor has been detected Shriek, variant 2 All except infants Same as variant 1, except that variant 2 may express the more urgent nature of the aerial predator encounter. Click All except infants <2 weeks The click is a low-arousal "location marker" that draws attention to a caller. Close-Mouth Click Series (CMCS) All except infants <2 months Moderate-arousal "location marker" Open-Mouth Click Series (OMCS) All except infants A "location marker" reserved for a limited number of contexts of very high arousal; also appears to serve as a cue that aids in the synchronization of yaps Yap All except infants Carnivore mobbing call
+ Infant Affiliative VocalizationsCallInferred Function Infant Contact Call Conspecific vocal contact; functions initially to attract the mother and later as a precursor to moans and wails Infant Trill, variant 1 Expresses desire for, and contentment from, conspecific contact Infant Trill, variant 2 May express contentment and/or crossing the sensory threshold from contentment to discomfort
+ Infant Distress VocalizationsCallInferred Function Infant Whit, variant 1 Infant distress call; expresses discomfort and/or distress Infant Whit, variant 2 Infant high-intensity distress call Infant Yelp Serves both as an affiliative and distress vocalization in eliciting prompt retrieval by the mother
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