Division of labour within cooperatively breeding groups

Within cooperative societies, group members share in caring for offspring. Although division of labour among group members has been relatively well studied in insects, less is known about vertebrates. Most studies of avian helping focus solely on the extent to which helpers provision the offspring, however, helpers can participate in everything from nest building to predator defence. Bad provisioners may, for example, not be as 'uncooperative' as they appear. if they are good defenders. Thus, the distribution of helping tasks between group members should have important implications for our interpretation of group dynamics. Here, we compare two distinct forms of helping behaviour in the cooperatively breeding noisy miner (Manorina melanocephala): chick provisioning and mobbing nest predators. We show that the way in which individual helpers invest in these two helping behaviours varies enormously across individuals and among social groups. Good provisioners often contributed relatively little to mobbing and vice versa. Indeed, (18%) of helpers only mobbed, 22% just provisioned, whereas 60% of helpers performed both forms of helping. Across nests, provisioning was significantly negatively correlated with mobbing effort. We suggest that small differences in the costs or benefits of different aspects of helping (due to differences in age, relatedness or social status) have a big impact on the division of labour within a group. Consequently, social groups can be made up from individuals who often specialise in one helping behaviour, and/or helpers who perform a number of behaviours to differing degrees. Division of labour within social groups will, therefore, have important consequences for the maintenance of cooperatively breeding in vertebrates.

On labour market dualism in the Lewis model: A comment

In a special issue of this journal commemorating the 50th anniversary of W. Arthur Lewis's (The Manchester School, Vol. 28 (1954), No. 2, pp. 139-191) seminal paper, the Lewis model is treated as a model of labour market dualism (Fields, The Manchester School, Vol. 72 (2004), No. 6, pp. 724-735). This interpretation is flawed for a number of reasons. First, it overemphasizes the role ascribed by Lewis to intersectoral earnings differentials in his original model. Second, it fails to acknowledge that a major shortcoming of the model was its inability to account for the widening intersectoral earnings differential observed across a wide range of developing economies. For Lewis himself this was one of the 'major theoretical puzzles of the period' (1979, p. 150). Third, it ignores Lewis's subsequent revision of the model (Lewis, The Manchester School, Vol. 47 (1979), No. 3, pp. 211-229) that, ironically, incorporates a dual labour market to resolve this puzzle. However, for Lewis the critical issue was dualism within the modern sector, not, as Fields understands it, labour market dualism between the modern and traditional sectors. Fields's appreciation of the contribution of the Lewis model to understanding the process of wage determination in developing economies is therefore misplaced.

Folk singers during Labour Day march Brisbane 1965

Folk singers during the Labor Day procession, in Brisbane, Australia, May 1965. One person holds a banner relating to the S.S. Binburra

Queensland Trades and Labor Council float with banner during Labour Day march Brisbane 1965

Queensland Trades and Labor Council float with banner during the Labor Day procession, May 1965, Brisbane Australia.

Participants with Equal pay placard during Labour Day march Brisbane 1965

Participants with Equal pay placard in Brisbane, Australia, during the Labor Day procession, May 1965.

Marchers with banners during Labour Day march Brisbane 1965

Marchers with banners in Brisbane, Australia, during the Labor Day procession, May 1965.

Rethinking the labour movement in the "new South Africa"

The socio-economic system underpinning apartheid in South Africa was based on the exploitation of black workers in the mines, the factories, the fields and the shops. It is widely recognized that the struggles of the South African black working class contributed decisively to the overthrow of the racist regime. In recognition of the power of organised labour, the democratic government elected in 1994 granted South Africa's unions unprecedented legal and constitutional rights. However, despite these gains, the country's labour movement has been facing a fresh set of challenges, from macroeconomic policy to the factory floor, many of them emanating from labour’s political allies in Government. The purpose of this book is to examine how the South African labour movement is responding to these challenges in the new millennium. A variety of experts on South African labour, both within the country and outside deal with crucial issues: How has South Africa's labour movement reacted to the ANC Government's neoliberal economic agenda? How do the unions relate to an increasingly diversifying, “flexible” and vulnerable workforce? What are labour’s prospects of contributing to a left project in democratic South Africa? What are the challenges facing the unions in relation to new forms of militancy and social movements?