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Trichromatic Colour Vision: The Choice between Red and Green Colour in Chlorocebus aethiops
No full textTwo main theories try to explain the nature of the selective pressure that led to trichromatic colour vision in primates. The foraging hypothesis suggests that colour discrimination is linked to the detection and selection of food, whereas another hypothesis connects trichromacy to the perception of skin colour signaling in a socio-sexual context. The goal of this study was to investigate which hypothesis could be the most plausible to explain the evolution of trichromatic colour vision. At this purpose the colour preference of a colony of vervet monkeys (Chlorocebus aethiops) hosted at Parco Natura Viva – Garda Zoological Park was investigated. Couples of red and green bags containing the same hidden reward were placed in the outdoor enclosure of vervet monkeys and their choice between red and green objects was recorded in order to investigate the effects of colour cues on object preference in the social context. Moreover, the hand used to retrieve objects was recorded to assess a possible relation between hand preference and colour choices. Results indicate that choices do not seem to be based on object colour. However, monkeys showed a significant right-hand preference to retrieve green objects. In conclusion, these observations seem not to support the foraging hypothesis of the origin of colour vision. Therefore, the role of intraspecific socio-sexual communication could be more plausible for the evolution of trichromacy, but this aspect should be better investigate in future studies
Infants in a colony of captive Chimpanzees: Social enrichment?
No full textSocial enrichment refers broadly to the social lives of chimpanzees as social interactions with other chimpanzees. Optimizing the management of social behavior is essential to maintaining a breeding population of chimpanzees that retain their behavioral competence over generations.
This study aims to underline whether and how newborns could be considered a social environmental enrichment for a colony of captive chimpanzees hosed at Parco Natura Viva, by comparing interactions between the different members of the colony and two young females: a 2-month-old infant, fully dependent on the care of her mother, and a 4-year-old infant, completely weaned.
Results highlight that the 2-month-old infant receives attentions significantly more from the mother and the grandmother than from the remaining subjects. On the contrary, the 4-year-old infant receives more interactions from the rest of the group rather than from her mother. Moreover, the grandmother of the 2-month-old infant acts as an allomother.
In conclusion, an infant may represent a social enrichment for a group of chimpanzees, since it stimulates social relationships among individuals, especially when the strong mother-infant bond becomes less exclusive
Dual-route imitation in preschool children
No full textImitation can be realized via two different routes: a direct route that translates visual input into motor output when gestures are meaningless or unknown, and a semantic route for known/meaningful gestures. Young infants show imitative behaviours compatible with the direct route, but little is known about the development of the semantic route, studied here for the first time. The present study examined preschool children (3–5 years of age) imitating gestures that could be transitive or intransitive, and meaningful or meaningless. Both routes for imitation were already present by three years of age, and children were more accurate at imitating meaningful-intransitive gestures than meaningless-intransitive ones; the reverse pattern was found for transitive gestures. Children preferred to use their dominant hand even if they had to anatomically imitate the model to do this, showing that a preference for specular imitation is not exclusive at these ages
Can greater flamingo recognize fertile vs. unfertile egg? A single case study
No full textFlamingos are colonial birds and in zoos are best kept in flocks of at least 20 birds. However reliable breeding occurs with flocks of more than 40 birds. Fertility of captive flamingos varies between different flocks, species and seasons. Knowing the reproductive history of each individual flamingo allows anticipating fertility/infertility in eggs and makes informed decisions as to whether to pull, allow recycling, substitute a dummy, or allow continued incubation. Infertile eggs (or the dummy eggs on the parents' nest) can be removed to encourage birds to relay. Pairs producing infertile first eggs will often produce fertile second eggs.
Flamingos appear to be unable to recognize their own egg and will incubate any object roughly the correct size and shape. This study investigated the behaviours of the male and the female of a pair of Greater flamingos’ colony housed at Parco Natura Viva in order to detect their ability to recognise fertile and unfertile eggs. The behaviours of the male and the female of the pair were collected over the first period of incubation - the unfertile egg - and the second period of incubation – the fertile egg. Results of this study underline that the female performed different behaviours between the infertile egg incubation period and the fertile egg incubation period; whereas no behavioural differences of the male were found between the two periods. These findings seem to highlight that flamingos might be able to detect infertile eggs, especially the female of the pair. The results of this study can make a difference in the care and management of captive colony of Greater flamingos. However, further researches are needed to observe the behaviour of greater flamingos in order to determine behavioural differences between fertile and unfertile eggs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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