Production and perception of situationally variable alarm calls in wild tufted capuchin monkeys (Cebus apella nigritus)

Abstract

Production and perception of situationally variable alarm calls in wild tuftedby examining responses to predator and snake decoys encountered at various distances 34 (reflecting differences in risk-urgency). Observations in natural situations were conducted to 35 determine if predator-associated calls were given in additional contexts. Results indicate the use 36 of three call types. ÒBarksÓ are elicited exclusively by aerial threats but the call most commonly 37given to terrestrial threats (the ÒhiccupÓ) is given in non-predatory contexts. The rate in which 38 this latter call is produced reflects risk-urgency. Playbacks of these two call types indicate that 39 each elicits appropriate anti-predator behaviors. The third call type, the ÒpeepÓ, seems to be 40 specific to terrestrial threats, but it is unknown if the call elicits predator-specific responses. 41

The alarm call system of wild black-fronted titi monkeys, Callicebus nigrifrons

“…These findings are consistent with the current theory of primate alarm calls, which states that aerial and terrestrial predators elicit acoustically distinct vocal behaviour (e.g., Seyfarth and Cheney 1980;Macedonia and Evans 1993;Zuberbühler 2000b;Digweed et al 2005;Fichtel et al 2005;Kirchhof and Hammerschmidt 2006;Schel et al 2009;Wheeler 2010). However, they are also at odds with N number of events per predator stimuli recorded and analysed.…”

“…6 this general theory in a number of ways. Firstly, titi monkeys regularly produce B calls not only to terrestrial predators but also in non-predatory contexts, something that has also been observed in other New World primates, particularly during inter-group encounters (Digweed et al 2005;Fichtel et al 2005;Kirchhof and Hammerschmidt 2006;Wheeler 2010). In putty-nosed monkeys (Cercopithecus nictitans martini), males regularly produce loud and conspicuous calls to predators (Arnold and Zuberbühler 2006a, b), but the same calls are also produced during non-predator events, such as during inter-group encounters, to falling branches, or to initiate group travel Zuberbühler 2006a, 2008).…”

“…Although predatorspecific alarm calls are well described in Old World monkeys (see Zuberbühler 2009 for a review), this is not the case for most New World monkeys (but see Digweed et al 2005;Fichtel et al 2005;Kirchhof and Hammerschmidt 2006;Wheeler 2010), which besides having undergone an independent radiation within the primate lineage also differ in essential life-history and socio-ecological characteristics from cercopithecines and lemurs (Strier 2007). Therefore, discovering whether and how titi monkeys use specific vocal signals when interacting with predators thus has considerable theoretical implications for evolutionary theories of primate communication and cognitive process underlying call production.…”

Suffixation influences receivers' behaviour in non-human primates

“…In some species, natural selection has favoured the evolution of acoustically distinct alarm calls with call variants related to the type of predator, the degree of threat or the appropriate anti-predator behaviour. Evidence is not restricted to primates but also includes a range of other taxa, including birds [5][6][7], non-primate mammals ( prairie dogs (Cynomys gunnisoni) [8], suricates [9]) and non-human primates (lemurs (Lemur catta) [10], Old World monkeys (Cercopithecoidae) [11 -14], New World monkeys (Platyrrhini) [15][16][17][18], apes (Hominoidea) [19]). Although these findings have been interpreted in terms of potential parallels to human language, animal alarm call systems usually lack flexibility, arbitrariness in acoustic structure and generativity, indicating profound differences between animal communication and human language [20 -22].…”

Evidence for semantic communication in titi monkey alarm calls

“…The conclusion was that the aerial and terrestrial alarm calls of S. mystax were functionally referential, but that in S. fuscicollis functionally referential calls were only present to aerial but not terrestrial predators. Similarly, Wheeler (2010) demonstrated that tufted capuchin monkeys, Cebus apella, showed appropriate responses after hearing 'barks' (aerial predator calls) and 'hiccups' (generalized disturbance call), and that these calls were made in the appropriate contexts.…”