Morphological modifications of vocal anatomy are widespread among vertebrates, and the investigation physiological mechanisms adaptive functions such variants is an important focus research into evolution communication. The 'descended larynx' adult humans has traditionally been considered unique to our species, representing adaptation for articulate speech, debate concerning position larynx in extinct hominids assumes that a lowered diagnostic speech language. Here, we use bioacoustic...

The field of animal vocal communication has benefited greatly from improved understanding production mechanisms and specifically the generalization source–filter theory speech to non-human mammals. application enabled researchers decompose acoustic structure signals according their mode thereby predict variation that is caused by anatomical or physiological attributes caller. states result a two-stage production, with glottal wave generated in larynx (the source), being subsequently filtered...

Nonlinear phenomena (NLP) are often associated with high arousal and function to grab attention and/or signal urgency in vocalizations such as distress calls. Although biomechanical models vivo / ex experiments suggest that their occurrence reflects the destabilization of vocal fold vibration under intense subglottal pressure muscle tension, comprehensive descriptions dynamics NLP natural signals critically lacking. Here, plug this gap, we report timing, type, extent acoustic context 12 011...

Nonlinear acoustic phenomena (NLP) likely facilitate the expression of distress in animal vocalizations, making calls perceptually rough and hard to ignore. Yet, their function adult human vocal communication remains poorly understood. Here, examine production perception correlates pain spontaneous nonverbal we take advantage childbirth—a natural context which labouring women typically produce a range highly evocative loud including moans screams—as they experience excruciating pain. We...

At some point in our evolutionary history, humans lost vocal membranes and air sacs, representing an unexpected simplification of the apparatus relative to other great apes. One hypothesis is that these simplifications represent anatomical adaptations for speech because a simpler larynx provides suitably stable tonal source with fewer nonlinear phenomena (NLP). The key assumption NLP reduce intelligibility indirectly supported by studies dysphonia, but it has not been experimentally tested....

While vocal tract resonances or formants are key acoustic parameters that define differences between phonemes in human speech, little is known about their function animal communication. Here, we used playback experiments to present red deer stags with re-synthesized vocalizations which formant frequencies were systematically altered simulate callers of different body sizes. In response stimuli where lower indicated longer tracts, more attentive, replied roars and extended tracts further...

Individual recognition is considered a complex process and, although it believed to be widespread across animal taxa, the cognitive mechanisms underlying this ability are poorly understood. An essential feature of individual in humans that cross-modal, allowing matching current sensory cues identity with stored information about specific from other modalities. Here, we use cross-modal expectancy violation paradigm provide clear and systematic demonstration nonhuman animal: domestic horse....

Surprisingly little is known about the role of acoustic cues in mammal female mate choice. Here, we examine response red deer ( Cervus elaphus ) to male roars which an cue body size, formants, has been re-scaled simulate different size callers. Our results show that oestrous hinds prefer simulating larger callers and constitute first evidence mammals use a choice context. We go on suggest sexual selection through mating preferences may have provided additional pressure along with male–male...

Males often face a trade-off between investments in precopulatory and postcopulatory traits [1], particularly when male-male contest competition determines access to mates [2]. To date, studies of strategies have largely focused on visual ornaments (e.g., coloration) or weapon morphology antlers, horns, canines). However, vocalizations can also play an important role both male female choice [3-5]. We investigated variation vocal tract dimensions among howler monkeys (Alouatta spp.), which...

Abstract Recent studies have revealed that some mammals possess adaptations enable them to produce vocal signals with much lower fundamental frequency ( F 0) and formant spacing (Δ ) than expected for their size. Although these are assumed reflect selection pressures males components exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show male terrestrial Δ (but mating systems greater sexual dimorphism. We also reveal...

Until recently, human nonverbal vocalisations such as cries, laughs, screams, moans, and groans have received relatively little attention in the behavioural sciences. Yet these vocal signals are ubiquitous social interactions across diverse cultures may represent a missing link between fixed nonhuman animal highly flexible speech. Here, we review converging empirical evidence that acoustic structure ("forms") of affective sounds humans reflect their evolved biological "functions". Human thus...

In most human societies, grandparents often provide substantial care and support for their grandchildren, including as babies. Given that previous studies have shown ageing is accompanied by a gradual decline in our ability to identify other people’s emotions, does age also reduce skill at understanding baby’s cries? Here, we show older people with experience of caring babies remain able correctly decode the information conveyed babies’ cries. The results psychoacoustic experiments underline...

Pet-directed speech is strikingly similar to infant-directed speech, a peculiar speaking pattern with higher pitch and slower tempo known engage infants' attention promote language learning. Here, we report the first investigation of potential factors modulating use dog-directed as well its immediate impact on dogs' behaviour. We recorded adult participants in front pictures puppies, old dogs, analysed quality their speech. then performed playback experiments assess reaction compared normal...

Humans as well many animal species reveal their emotional state in voice. Vocal features show strikingly similar correlation patterns with states across mammalian species, suggesting that the vocal expression of emotion follows highly conserved signalling rules. To fully understand principles mammals it is, however, necessary to also account for any inconsistencies way they are acoustically encoded. Here we investigate whether emotions differs between call types produced by same species. We...

Inter-individual differences in human fundamental frequency ( F 0, perceived as voice pitch) predict mate quality and reproductive success, affect listeners' social attributions. Although humans can readily volitionally manipulate their vocal apparatus resultant pitch, for instance, the production of speech sounds singing, little is known about whether exploit this capacity to adjust non-verbal dimensions voices during (including sexual) interactions. Here, we recorded full-length...

Abstract We investigated whether the growls of domestic dogs, Canis familiaris , exhibit predictable variations in a range key acoustic parameters when they are given two contrasting experimental contexts, and humans sensitive to such variation. In standardized paradigm, an experimenter visited 32 dogs generated aggression context play context. these 204 isolated were recorded subsequently acoustically analysed. Contrary previous findings on barks, fundamental formant frequencies did not...