Parent–offspring communication in the Nile crocodile Crocodylus niloticus: do newborns’ calls show an individual signature?

@article{Vergne2006ParentoffspringCI,
  title={Parent–offspring communication in the Nile crocodile Crocodylus niloticus: do newborns’ calls show an individual signature?},
  author={Am{\'e}lie L. Vergne and Alexis Avril and Samuel Martin and Nicolas Mathevon},
  journal={Naturwissenschaften},
  year={2006},
  volume={94},
  pages={49-54}
}
Young Nile crocodiles Crocodylus niloticus start to produce calls inside the egg and carry on emitting sounds after hatching. These vocalizations elicit maternal care and influence the behaviour of other juveniles. In order to investigate the acoustic structure of these calls, focusing on a possible individual signature, we have performed acoustic analyses on 400 calls from ten young crocodiles during the first 4 days after hatching. Calls have a complex acoustic structure and are strongly… 
Acoustic communication in crocodiles: How do juvenile calls code information?
TLDR
By using calls modified in the temporal and the frequency domains, this work isolates the acoustic cues necessary to elicit a behavioral response from receivers, underlying the importance of the frequency modulation slope.
Size does matter: crocodile mothers react more to the voice of smaller offspring
TLDR
It is shown that acoustic communication has a key role in the dynamics of crocodilian’ mother-offspring relationships, and changes in acoustic interactions may go with the break of maternal care as well as dispersal of juvenile crocodilians.
Acoustic communication in crocodilians: information encoding and species specificity of juvenile calls
TLDR
Interestingly, using conditioning experiments, it was demonstrated that this tolerance in responses to signals of different acoustic structures was unlikely to be related to a lack of discriminatory abilities, reinforced the idea that crocodilians have developed adaptations to use sounds efficiently for communication needs.
Turtle vocalizations as the first evidence of posthatching parental care in chelonians.
TLDR
It is shown that hatchlings and adult turtles, Podocnemis expansa, produce sounds in and out of the water and that these sounds may be used to congregate hatchlings with adults for mass migration.
Vocalization by extant nonavian reptiles: A synthetic overview of phonation and the vocal apparatus
TLDR
The diversity of form of the sound producing apparatus and the increasing evidence that reptiles are more dependent upon vocalization as a communication medium than previously thought indicates that they have a significant role to play in the understanding of the evolution of vocalization in amniotes.
The distress call of Caiman crocodilus crocodilus (Crocodylia: Alligatoridae) in western Amazonia, Brazil.
TLDR
C crocodilians have the most complex acoustic repertoire, especially during the early stages of their life, having different functions according to their stimulus and being classified as hatching, contact, annoyance, threat and distress calls.
Vocal patterns of adult females and juveniles Caiman yacare (Crocodilia: Alligatoridae) in Brazilian Pantanal wetland.
TLDR
The Paraguayan caiman (Caiman yacare) is the main Caimaninae species occurring in the Brazilian Pantanal Wetland and it is hypothesized that the variation in the distress call pattern may be associated to a low specificity in sound recognition by adult caimans.
Vocalizations in two rare crocodilian species: A comparative analysis of distress calls of Tomistoma schlegelii (Müller, 1838) and Gavialis gangeticus (Gmelin, 1789)
TLDR
Distress calls of T. schlegelii show numerous harmonics, whereas extensive pulse trains are present in G. gangeticus, and a negative correlation of increasing body size with de- creasing dominant frequencies is recorded.
RESPONSES OF JUVENILE AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) TO CONTACT CALLS
TLDR
This study tests juvenile American alligators' ability to respond via movement and callback vocalizations to pre-recorded conspecific contact calls across a large sample size, and tests for relationships between response rates and juvenile body size and sex.
...
...

References

SHOWING 1-10 OF 19 REFERENCES
Vocal signature recognition of mothers by fur seal pups
TLDR
Investigation of how pups recognize their mother's calls found that they seemed to rely mainly on spectral analyses, as mothers mainly use temporal structures to recognize their pup's calls.
Individual identity coding depends on call type in the South Polar skua Catharacta maccormicki
TLDR
Both courtship and contact calls have a higher potentiality of individual identity coding than the alarm call, and this last result can be extrapolated to many other species.
"Distress Calls" of Crocodilians -- Whom Do They Benefit?
TLDR
The call is frequently referred to as the "distress call," although Neill (1971) chose to restrict he use of this term to the louder, higher-pitched call evoked by a high degree of excitement, i.e., seizure by a predator.
Vocalization in juvenile crocodilians.
TLDR
Evidence is presented that the grunts and distress calls of juvenile alligators are examples of graded calls, which are given in different form depending largely on contest.
Observations on Maternal Behavior of the American Alligator, Alligator mississippiensis
TLDR
Maternal behavior of four female alligators was observed over a six year period at Okefenokee Swamp, Georgia and vocal interactions between mothers and offspring indicate the possibility of a temporal relationship between maternal vocalizations and/or movements and offspring vocalizations.
How to vocally identify kin in a crowd: The penguin model
Snake Bioacoustics: Toward a Richer Understanding of the Behavioral Ecology of Snakes
  • B. Young
  • Environmental Science
    The Quarterly Review of Biology
  • 2003
TLDR
The ability of snakes to contextualize the sounds and respond with consistent predatory or defensive behaviors suggests that auditory stimuli may play a larger role in the behavioral ecology of snakes than was previously realized.
Signalling systems for individual recognition: an information theory approach
Principles of Animal Communication
Part 1 Production, transmission, and reception of signals: the properties of sound fourier analysis sound production sound propogation sound reception properties of light production and transmission
Information and Communication
Information and Prediction in ScienceProceedings of a Symposium sponsored by the Académie Internationale de Philosophie des Sciences, held in Brussels 3–8 September, 1962. Edited by S. Dockx and P.
...
...