摘要:

The societies of Isoptera and Hymenoptera differ in two general features. 1. The termite societies are bisexual. From a primitive symmetry between both sexes, many asymmetries appeared during the course of their evolution. These asymmetries are related either to a sexual dimorphism, or a biased sex ratio, or both, and are differently expressed in the separate castes of a given species. 2. The hemimetabolous development allows a termite to take part in the social tasks before the end of its postembryonic development, and even to reproduce at a larval stage (neoteny). Thus Isoptera exhibit a polymorphism of larvae, unlike Hymenoptera where a polymorphism of imagoes is observed. Moreover, an individual can change its physical caste: this temporal polymorphism never exists in Hymenoptera. These facts have important consequences for the caste system and its evolution. The differences between the social structures of Isoptera and Hymenoptera are related to the differences between their non-social ancestors.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525528

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This article starts with a brief description of the phenomenon of song learning in birds, and then outlines various consequences that it has for the individuals that show it and the groups to which they belong. Among these are the following features, each of which has been described in at least some species: the sharing of song between kin and between neighbours; changes in song with time; changes with distance, including the phenomenon of dialects. The final section is a discussion of which of these consequences may have functional significance and so be likely to be an advantage of song learning. It is suggested that cultural evolution, geographical variation and dialect boundaries, being features of populations rather than individuals, are epiphenomena without functional significance in themselves. However, song learning may confer advantages stemming from the copying process itself, in interactions with neighbours and in matching song to habitat. The evidence that learnt dialects have a role in assortative mating is less convincing. It is likely both that song learning has different functions in different species, and that it has more than a single function in many of them.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525529

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Pigeons considerably experienced in homing (EX) and others completely inexperienced (IN) were released simultaneously at sites approximately 30 and 150 km from their home loft at Würzburg, Germany. Some of them had been made anosmic by means of bilateral olfactory nerve section (experimentais, EP); untreated birds served as controls (CP).

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525530

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The initial orientation of homing pigeons subjected to various magnetic disturbances prior to releases was studied. Sine wave oscillations of the magnetic field had no effect at low frequencies, whereas there was a significant and increasing effect at frequencies above 0.42 Hz. Oscillations of either the vertical or horizontal component of the earth's magnetic field were found to have an effect on initial orientation. Keeping the pigeons in a near zero magnetic field or in a natural magnetic field from which either the vertical or horizontal component had been removed also resulted in errors of initial orientation. No significant differences, however, were found in homing performance.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525531

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525532

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The great majority of adult Swiss albino males exhibit infanticide when sexually naive, but after mating and cohabitation with females they show paternal or amicable behaviour towards pups.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525533

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The behaviour of lactating house mice (Mus domesticus) with litters of young of different degrees of relatedness was analyzed under different environmental conditions to test whether females recognize and discriminate in their maternal behaviour between own and alien young. Both under ad libitum and under restricted feeding there was no significant difference in the amount of time a female spent nursing or licking own versus alien young (litters consisted of four own and four unrelated alien pups, cross-fostered on day 1 of lactation). Weaning weight was also not significantly different. Under restricted feeding the females reduced their litter sizes by killing some young. On average five out of eight pups survived until weaning. The females killed as many own as alien pups. In a third series of experiments two females (either familiar sisters or unrelated, unfamiliar females) were allowed to share a communal nest and they always indiscriminately nursed both litters (food was available ad libitum). However, the degree of relatedness of the females sharing a communal nest did affect their lifetime reproductive success (measured as the number of offspring weaned during a lifetime of 6 months): a female sharing a nest with a sister weaned significantly more young than a monogamously paired female; the reproductive success of a female living with an unrelated partner did not differ significantly from that of a monogamous female or from that of a female living with a sister. Although females did not discriminate in their maternal behaviour between own and alien young in the same nest, kin recognition might be important for choosing a partner for cooperative brood care.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525534

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Kin discrimination should be a tactic in the fitness strategy of individuals. Two postulates derived from inclusive fitness theory that fitness benefits toward kin are correlated with degree of relatedness and that social behavior of members of a kin group is always cooperative are refuted by analyses of the social dynamics of yellowbellied marmots. Cooperative behavior occurs predominantly between mother/ daughter and sister/sister pairs, but such pairs also compete. More distant kin are treated similarly to unrelated animals, social behavior is primarily agonistic. Patterns of space-use, matrilineal formation and organization, social dynamics, and reproductive suppression of close kin suggest that marmots attempt to maximize direct fitness.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525535

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Bird song is a well-studied communication system which at first sight would seem to have the potential to transmit information on kinship. However there are very few examples of kin recognition by song (as distinct from calls). It is argued that this rarity is a consequence of two developmental constraints. Firstly, females do not usually sing, therefore song cannot give cues on female kinship. Secondly, in most species studied to date males learn their songs from neighbours (non-kin) rather than fathers, therefore a male's song is not related to kinship.

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525536

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

ISSN:0394-9370    

DOI:10.1080/08927014.1989.9525537

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor