Rosie Cooney

Inbreeding avoidance and reproductive skew in a cooperative mammal

In animal social groups, socially subordinate individuals frequently show low reproductive success or completely fail to breed. This suppression of subordinate reproduction is currently typically attributed to control by dominant individuals. However, subordinates in cooperative groups often lack access to unrelated mates, and an alternative possibility is that their reproduction is limited by inbreeding avoidance. Using the eusocial Damaraland mole–rat Cryptomys damarensis, this paper provides the first experimental evidence, to our knowledge, for this explanation. Subordinate, non–breeding female mole–rats were given access to unrelated mates while remaining in the presence of dominant females, and many became reproductively active soon after unrelated males were introduced. Inbreeding avoidance and the availability of unrelated mates provides a plausible and untested explanation for variation in reproductive skew across animal societies.

Territorial defence is the major function of female song in the superb fairy-wren, Malurus cyaneus

Abstract Unlike most passerines, female superb fairy-wrens are prolific solo singers. Four hypotheses for the function of female song were evaluated: (1) to defend territories; (2) to maintain contact with mates; (3) to assess the amount of time mates are spending on the territory; and (4) to solicit displays from extra-group males. Female song rates increased as fairy-wrens reasserted territorial boundaries after a period of communal winter flocking. Song rates were not affected by the age of the female, the time she had been paired to her current mate, the time her mate had been the dominant male on the territory, or the composition of her group. However, females that had recently established territories, or had undergone significant changes in territorial borders, sang at higher rates than females that had been established in their territories for many years. Playback experiments revealed that: (1) females were more likely to sing in response to songs of male or female neighbours than to songs of their mates or their own song; (2) females responded more intensely to songs of female strangers than to songs of female neighbours; (3) extra-group males did not respond with extra-group courtship displays when a females song was played back from her territory, although some territorial responses were elicited. The stronger response to neighbours indicates that mate location and mate assessment are not major functions of female song. The display solicitation hypothesis can be rejected because extra-group males did not respond to playbacks of females, and there was no correlation between female song rate and the incidence of male display. In contrast, the results suggest that the major function of female song is territorial defence, and that receivers use variation in the song to discriminate between different classes of individuals (self, mate, neighbour, stranger).

CITES and the CBD: Tensions and Synergies

The international legal regime for the protection of biological diversity evolved, throughout the last half of the twentieth century, in an ad hoc and piecemeal fashion, reflecting changing political realities, conservation challenges and the rapidly developing scope and nature of international environmental law. This fragmented and unsystematic development, in the face of ecological challenges on a global scale, raises serious problems of lack of coordination, replication of efforts and policy divergence between regimes. Concern about these inefficiencies has prompted a range of recent initiatives to promote coherent links between environmental agreements, with the United Nations Environment Programme (UNEP) as the prime motivator. These include an ongoing project focusing on the harmonization of national reporting requirements, a United Nations University/UNEP 1999 Conference on ‘Interlinkages: Synergies and Coordination between Multilateral Environmental Agreements’, and statements or substantive action brought about by many multilateral environmental agreements (MEAs) to address the need for cooperation.

A Long and Winding Road? Precaution from Principle to Practice in Biodiversity Conservation

This challenging book takes a broad and thought-provoking look at the precautionary principle and its implementation, or potential implementation, in a number of fields. In particular, it explores the challenges faced by public decision-making processes when applying the precautionary principle, including its role in risk management and risk assessment. Frameworks for improved decision-making are considered, followed by a detailed analysis of prospective applications of the precautionary principle in a number of emerging fields including: nanotechnology, climate change, natural resource management and public health policy. The analysis is both coherent and interdisciplinary, employing perspectives from law, the social sciences and public policy with a view to improving both the legitimacy and effectiveness of public policy at national and international levels.

THE DAMARALAND MOLE-RAT: SOCIAL LIFE IN THE KALAHARI

SUMMARY The mole-rats of sub-Sarahan Africa are a taxon uniquely suited for examining hypotheses of social evolution. The Damaraland mole-rat, found in Kalahari red sands, displays an elaborate extended form of cooperative breeding. Here I review recent developments concerning the evolution of sociality in mole-rats, and discuss these in the light of current theories of the evolution of cooperative breeding. The central importance of the ecology of the Kalahari in shaping group size and group dynamics in the Damaraland mole-rat is emphasised.