Chloroplast microsatellites: new tools for studies in plant ecology and systematics

The nonrecombinant, uniparentally inherited nature of organelle genomes
makes them useful tools for evolutionary studies. However, in plants, detecting
useful polymorphism at the population level is often difficult because of the
low level of substitutions in the chloroplast genome, and because of the slow
substitution rates and intramolecular recombination of mtDNA. Chloroplast
microsatellites represent potentially useful markers to circumvent this problem
and, to date, studies have demonstrated high levels of intraspecific variability.
Here,we discuss the use of these markers in ecological and evolutionary
studies of plants, as well as highlighting some of the potential problems
associated with such use.

Developing Creative Solutions to the Problems of Children and their Families: Communicative Reason and the use fo Forum Theatre

Building on Habermas’s conceptualisation of modes of reasoning, the authors proposed that an application of critical theory to the present bureaucratised nature of communication between state representatives and welfare recipients (Howe 1992) might open up ways in which social workers could reconceptualise their practice. In a subsequent edition of this journal, three of the present authors introduced the radical theatre of Augusto Boal as a methodology which might provide an expressive route for social workers seeking to build a practice combining the intellectual analysis of critical theory with new ways of working (Spratt et al. 2000). Boal’s method recognises the oppressed status of groups who come to the attention of agents of the state and, through the use of a range of theatrical techniques, introduces strategies to facilitate the conscious recognition of such collective oppressions and develop dialogical ways to address them. In the last paper, the authors presented one such technique, ‘image theatre’, and demonstrated its use with social workers in consciousness raising and developing strategies for collective action.

The Equalization of Effective Communicative Freedom: Democratic Justice in the Constitutional State and Beyond

Jurgen Habermas takes the realization of rights through the democratic self-organization of legal communities to be the normative core of emancipatory politics. In this article I explore the implications of this claim in relation to the requirements of justice. I argue that Habermas's discourse theory of democratic legitimacy presupposes a substantive principle of justice that demands the equalization of effective communicative freedom for all structurally constituted social groups in any constitutional state. This involves the elimination of a range of structural injustices rooted in the complex interrelationships between political, economic and cultural orders. In the final section I sketch briefly the implications of this analysis in the context of ongoing globalization processes. It is suggested that the most effective way to establish a just system of global governance is to equalize effective communicative freedom among nation-states.

Long-term ecology of native pinewood communities in East Glen Affric, Scotland

Fossil pollen, stomata and charcoal were examined from a lake sedimentary sequence in the Glen Affric National Nature Reserve, one of the largest areas of remnant native pine woodland in Scotland, in order to assess ecosystem dynamics over the last 11 000 years. Results reveal that pinewood communities have been continuously present in East Glen Affric for the last 8300 years. Pinus sylvestris fi rst arrived in the area around 9900 cal. BP, but occurred in only low abundance for the subsequent 1600 years. Pine populations expanded around 8300 cal. BP and remained in relatively constant abundance throughout the remainder of the Holocene. There is no evidence of a hypothesized regional mid-Holocene ‘ pine decline ’ at the site. Charcoal results reveal that pinewood communities in East Glen Affric do not appear to have been dependent on fire for either their establishment or their maintenance as has previously been suggested.

Effects of the acanthocephalan parasite Echinorhynchus truttae on the feeding ecology of Gammarus pulex (Crustacea : Amphipoda)

The amphipod Gammarus pulex is an intermediate host to the acanthocephalan fish parasite Echinorhynchus truttae. Gammarus pulex has a wide trophic repertoire, feeding as a herbivore, detritivore and predator. In this study an examination was made of the effects of E. truttae parasitism on components of the G. pulex diet: stream-conditioned leaves, dead chironomids and live juvenile isopods Asellus aquaticus. Over 21 days, parasitism had no effect on daily feeding rates or wet weights of G. pulex fed on leaves or chironomids. Parasitism had a significant effect on the number of A. aquaticus killed by G. pulex, with parasitized individuals killing significantly fewer than their unparasitized counterparts. In addition, unparasitized amphipods killed all size classes of A. aquaticus indiscriminately, whereas parasitized animals tended to kill the smaller size classes. The impacts of the parasitism of G. pulex throughout the wider freshwater community are discussed.

Developing critical social work in theory and in practice: child protection and communicative reason

This paper argues that a critical analysis of the ideologies that inform contemporary child care has been missing from the ‘re-focusing debate’. Such an analysis points up the necessity of reasserting a critical social work position in order to provide a basis for reconstructing practice and engaging with other social actors and their ideologies in an open and creative fashion compatible with Habermas’ aspiration of ‘communicative reason’.