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In our study we taught a female African Grey 11 Italian words: vowel-like sounds were extracted from comprehensible words after critical listening, and pitch frequency (Pkf) was measured for the first three formants of each vowel. Similarly, formants from human vowels were isolated and measured. The analysis run on formant frequencies mean values of both samples revealed that human vowels could be separated on the basis of the first three formants. Comparison between each human vowel and its parrot counterpart revealed that four out of five parrot vowels could be considered statistically different from human ones regarding the first two formants, but comparison between F 2 /F 1 and F 3 /F 2 are not significant. Our results suggest that formant spaces do exist in the vocalic production of a talking bird. This leads to interesting conclusions about generalization skills involved in speech recognition, vowel parsing patterns and label production.

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Subsongs are vocal trials uttered by young birds to practice songs. Among songbirds, subsongs are displayed by individuals in their first year of life. Studies on Zebra Finches Poephila guttata suggest that the juveniles learn their songs from a vocal tutor, their father. In this study we examine the subsongs in six captive-born Meyer's Parrots Poicephalus meyeri, from fledging time to weaning. Recordings of songs from chicks and fathers were analyzed for similarities in frequency and time parameters. With age, the subsongs of the chicks became more similar to the vocalizations of the fathers with 20% similarity rating in the first week after fledging to 100% at weaning time. Moreover, fledged chicks were exposed to a wide range of stimuli from several species of parrots breeding pairs caged nearby but chicks exclusively learned their fathers' songs. Our data support the hypothesis that Meyer's Parrots are vocal learners and use their father as their tutor.

Few species of reptiles are known to establish stable social structures and among these, chelonians provided scarce and conflicting results. Moreover, studies on turtles are usually performed on adult individuals. In this study, we checked whether and when hatchlings of the European Pond Turtle (Emys orbicularis galloitalica) established stable hierarchical structures in their first year of life, whether hierarchies were stable in time and how steady they were. We also verified whether social ranks were associated to the individuals’ size. We observed dyadic interactions daily within three small groups of turtles reared in a controlled environment for seven months. After two months, the hatchlings started to interact and progressively established stable hierarchical structures. However, the effectiveness of the three types of observed aggressive behaviors in reversing social ranks was low and the resulting hierarchies were flat. We did not find a significant effect of the turtles’ size on their interactions’ outcome and hierarchy structure. Our results provide clear evidence of the development and the characteristics of social behaviors in young reptiles in captivity. This study could be a starting point for investigating social structures in wild populations.