1,721,027 research outputs found
Influence of social status on paternal behaviour in mice
No full textHouse mice (_Mus musculus domesticus_) in triads of one female and two males showed differences in parental behaviour and the influence of male social status. Every test consisted in putting a strange test-pup into the cage of the triad. Many parental activities and particularly retrieving were recorded. The results demonstrated the social dominance of the female on the males, while the males maintained their hierarchy status, whether the female was present or not. The “killer” dominant male was less interested in parental care than the “normal” dominant male. The origin of such behaviour in relation to the possible social situation of the “killer” male in a natural environment is discussed
Evolution of parental care in tetrapods
No full textSe uno degli sforzi maggiori nella vita di ogni specie è quello di aumentare o quanto meno mantenere alta la propria fitness, è indubbio che le cure parentali sono uno dei mezzi migliori per raggiungere quello scopo. Nei vertebrati le cure parentali sono molto più sviluppate che in altri taxa, specialmente se andiamo a considerare gli aspetti delle cure che potremmo definire "attivi", in cui cioè non si ha semplice preoccupazione per la scelta del substrato per la deposizione delle uova, la loro mimetizzazione o la fornitura di cibo già pronto per la larva che nasce, ma si registra la coesistenza del genitore accanto alla covata prima e ai piccoli dopo la nascita, al loro nutrimento, protezione dai predatori, fino alle raffinate forme di insegnamento e trasmissione culturale di informazioni che rinveniamo nelle due classi tipicamente endoterme.
Indubbiamente i vertebrati, e tra questi in particolar modo le classi terrestri, cioè i tetrapodi, sono stati avvantaggiati nel poter sviluppare atteggiamenti parentali dall'avere una lunga vita media e dalla forte tendenza alla socialità. Tutto questo si è riflettuto nella possibilità di potersi riprodurre più volte (iteroparità) dedicandosi quindi volta per volta alla progenie anzichè puntare tutte le proprie chances di fitness in un'unica "scommessa" riproduttiva (semelparità). In tal modo la prole poteva essere ridotta di numero (senza necessariamente arrivare ad avere un numero totale di figli inferiore alle specie semelpare), comportando l'imbocco della strada verso una selezione di tipo K (pochi figli, ma estremamente fit) anzichè una di tipo r (molti figli, ma con minimo intervento parentale per assicurarne la sopravvivenza).
Lo scopo di questa review non è quello di essere esaustiva, ma di cercare di dare qualche indicazione su alcuni comportamenti parentali, cercando nel contempo di mostrare come l'evoluzione filogenetica e comportamentale non sono processo indipendenti o tutt'al più paralleli, ma con interazioni continue e reciproche influenze
Infant signals
No full textThis chapter reviews the adaptive origin, significance and presence among the vertebrates of infant signals. These signals are convergent cues beared by young of almost all mammals and birds in order to be recognised as infants, then to elicit protective behaviour, also in strange adults; in fact, they are at the base of the adopting behaviour, even between specie
Early food experience and later preferences in young red-legged partridges
No full textThe present paper reports that in 3-month-old red-legged partridges (_Alectoris rufa_) early experience of certain foods, restricted to the 10 days after hatching, determines some later shifts of preference towards known foods. Vegetable seeds, insect larvae or commercial food dust were the foods used during the treatment period. The increase of preference, measured as grams of food eaten, was independent of the type of food tasted after hatching. The adaptive and applied implications of such a tendency are discussed
Paternal behaviour of the house mouse: the effect of social status
No full textPaternal behaviour in rodents has been studied only recently (Dudley, 1974; Beilharz, 1975; Elwood, 1975, 1977; Svare et al., 1977; Priestnall, 1979). With this work we wanted to search for variations in the paternal behaviour of mice, divided into three categories: (A) a female and a dominant male (that had previously killed a subordinate one); (B) a female, a dominant male and a subordinate one; (C) a dominant male and a subordinate one (females were removed just before the test)
Escape-reaction of captive young red-legged partridges (_Alectoris rufa_) reared with or without visual contact with man
No full textIt was noted that adult birds of _Alectoris rufa_, hatched and reared in captivity, cannot survive in nature after their release for restocking for hunting. An attempt was made to ascertain what effect various kinds of visual experiences with man during the first 2 months of life might have on the escape-response of young individuals. It was observed that absence of visual contact with man during the 48 h after hatching causes fear of human beings in those individuals when 2 months old. Conversely, subjects which were in visual contact with man during the 48 h after hatching did not show this tendency to escape in front of him. The possible links between this finding and the phenomenon of imprinting, together with the need for new rearing techniques, are discussed
Parental aggression displayed by female mice in relation to sex, reproductive status and infanticidal potential of conspecific intruders
No full textThe predatory behaviour of captive wild kestrels, _Falco tinnunculus_
No full textThe predatory behaviour of captive wild kestrels was investigated to ascertain whether prolonged captivity, with no predation opportunities, could affect prey capture. Thirty kestrels were observed. After a 48-hour fast they were offered a live laboratory mouse. The behaviour before and after prey appearance, and latency to predation were recorded. There was no difference in capture efficiency correlated with kestrel age, but adults performed preening significantly more often than young birds. Moreover, a clear inverse correlation was found between the latency of preening and of predation. Therefore, prolonged captivity associated with inactivity does not seem to exert a negative influence on predation in this species
Effects of captive breeding on the adaptive capability of the red-legged partridge (_Alectoris rufa_) in the wild
No full textA series of experiments has been carried out in order to verify whether the methods generally used in intensive husbandry of the red-legged partridge can influence the adaptive capability after the restocking in the wild. We showed the existence of several early sensitive-periods. They determine later the individual choices about attachment, flight response, food preferences
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