Zeitschrift fur Tierpsychologie最新文献

Analysed sound-spectrographically 129 field tape-recordings of the pant-hooting vocalization of seven chimpanzees at the Gombe Stream National Park, Tanzania. Quantitative statistical comparisons revealed that each animal had distinctive differences, sufficient to permit observers and probably chimpanzees to identify individuals. A consistent sexual difference was found, as well as a possible ageclass difference.

Male farm animals (kids, lambs and piglets) were kept isolated from conspecifics for their first 10 days of life. Until reaching sexual maturity they lived like pets in close contact with human beings; later some of them were removed to farms. Here they could interact with animals of other species, but not with conspecifics. Their first contact with conspecifics took place after they were sexually mature. In simultaneous choice experiments, offering a conspecific and a human being as passive participants, the animals were tested for any imprinted preference for human beings. Criteria were sexual advances and copulation attempts, as these indicate a strong social attachment. Two conditions proved necessary for imprinting on another species: 1. long-term isolation from conspecifics, and 2. close contact with another species during this time. Under these circumstances the term "sensitive period" may not be appropriate. Contrary to imprinting in birds isolation during the first days of life is not necessary for imprinting on another species to take place.

The behaviour of the African chevrotain (Hyemoschus aquaticus) was examined in 70 animals living in an enclosure. As far as possible every element of behaviour was seen in relationship to the animal's way of life in the field, and compared with the known behaviour of other Artiodactyla. It was attempted to ascertain the evolutionary stage of every behavioural element. Activity corresponds exactly to the dark period from 18.00 to 6.00. The males are by far more active than the females. An activity period during the night seems to be typical for the more primitive species. The sleeping position is reminiscent of the Suidae, the comfort behaviour of the smaller Artiodactyla. There is no mutual grooming. Hyemoschus aquaticus searches for food with its snout as do the Suidae, and can not rise on its hind legs as can most Artiodactyla. The alarm behavior is the same as in other forest-dwelling ruminants, behaviours of mainly visual importance are missing. Feces and urine are deposited anywhere. Both sexes announce their presence with these excrements, which are mixed with an excrete of the anal (male and female) and preputial glands (male). The interramal gland is occasionally used for marking twigs. Hyemoschus aquaticus does not have a single gland of the ruminant type. Fighting between females is seldom, between males more frequent, but of short duration. No demonstrations of rank order or territorial behaviour were observed. The male finds the female olfactorially. Precopulatory behaviour and copulation are similar to that of the Suidae. Early development and mother-infant behavior can be devided into 5 stages, which are described. Play behaviour of the young is very simple, there is no contact with peers. In its whole behaviour Hyemoschus aquaticus is the prototype of the solitary forest-dweller, more pig than ruminant. The Asian genus Tragulus of the same family is already more a ruminant than Hyemoschus aquaticus; the primitive Cervidae, with the genus Muntiacus, indicate the next level.

Newly hatched domestic chicks learned to prefer the object bearing the same visual characteristics as the environment associated to the initially preferred clucking sound. Domestic chicks chose after prenatal exposure between two different clucking sounds by running towards one loudspeaker and settling there. Then all chicks were individually exposed to two alternating optical stimulus situations of equal length, each of which was accompanied by one of the clucking sounds. Subsequently, in an exclusively visual choice situation, the chicks chose the stimulus that had been associated with the preferred clucking sound.

Equally sated three-spined sticklebacks (Gasterosteus aculeatus) that had a free view of stray individuals and of a swarm of Daphnia magna preferentially preyed upon the strays; the resulting risk to the strays increased with swarm density (a leads to c leads to e in Fig. 1). This applied also to situations with constant swarm numbers but varied density (a leads to b, d leads to e). The results from two experiments with equal swarm density (b/e, c/d) suggest selection to be affected also by swarm number and/or volume.

Yawning in reptiles was investigated in field observations of various lizard and tortoise species and in laboratory experiments with the tortoises Testudo h. hermanni and Emys orbicularis. In the experiments the animals' reactions to various conditions of temperature, air O2 and CO2 content, fatigue and hunger, were tested. Yawning and related or similar motor patterns are described and discussed.

Investigated the role of the odor of the flank gland in the stimulation of flank marking by male hamsters, Mesocricetus auratus. In the first experiment it was shown that a male has customary marking posts and that a second male introduced into the first male's area will mark in the same places. In experiment 2 nine test male male flank, marked less in the home cages of flank glandectomized male male than in the cages of normal male male. In experiment 3 it was shown that flank glandectomized male male marked at within the range of frequencies for normal male male.

Possible functions of territorial behavior were evaluated on the basis of observations of agonistic and reproductive activities of Uganda kob at a "territorial ground" (TG) in southwestern Uganda. We have found that male residents of a TG tend to occupy exclusive areas, and that agonistic interactions are concentrated along the boundaries separating adjacent occupied areas. Thus, we conclude that male kob do engage in the active defense of spatially exclusive territories at a TG.

The behaviour of the dragonfly E. fatime was observed in the field in the Near East, in Turkey and on Rhodos in the summers of 1971 and 1973. A short ethogram of the species is given and its behaviour compared with that of other dragonflies. On this basis its phylogenetic position is discussed.