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We used data from 12 allozyme loci for two endemic Brassicaceae from Gran Canaria (the endangered narrow endemic Crambe tamadabensis and its more widespread congener C. pritzelii) to assess whether their genetic diversity patterns reflect their phylogenetic closeness and contrasting population sizes and distribution areas, and to derive conservation implications. Genetic diversity values are high for both species and slightly higher in C. tamadabensis, despite its narrow distribution in north-western Gran Canaria. At odds with the generally high interpopulation diversity levels reported in Canarian endemics, values of GST in C. tamadabensis and C. pritzelii are rather low (0.067 and 0.126, respectively). We construe that the higher genetic structure detected in C. pritzelii is mainly a result of unbalanced allele frequencies and low population sizes at the edges of its distribution. The overall high allozyme variation detected in C. tamadabensis and C. pritzelii is nevertheless compatible with an incipient but consistent genetic differentiation between the two species, modulated by recurrent bottlenecks caused by grazing and drift. Our data suggest that conservation efforts aimed at maintaining the existing genetic connectivity in each species and ex situ conservation of seeds are the best strategies to conserve their genetic diversity. [ABSTRACT FROM AUTHOR]

The article discusses several community developments across the globe based on Utopian Ideals. Topics discussed include a self-proclaimed autonomous neighbourhood known as Freetown Christiania created in Copenhagen, Denmark, creation of Findhorn Ecovillage in Scotland thought to be the largest single intentional community in Great Britain and information on Arcosanti, an experimental town in the desert of Arizona, designed by architect Paulo Soleri.

Triacylglycerols occur in both the endosperm and embryo of Euphorbia lambii seeds. Upon germination, the amount of these neutral lipids in the endosperm decreased with 1.06 mg fatty acid day-1. The embryo contained 1.4 mg fatty acids in the triacylglycerols and this value declined slowly to 0.4 mg seedling-1 during the 8 day period of endosperm depletion. Radioactive acetate was rapidly taken up by the cotyledons of intact seedlings, translocated throughout the entire seedling, and up to 10.5% of the 14C proceeded to the sterols and latex triterpenols. Maximum uptake values of 1.4 μmol seedling-1 day-1 of acetate were measured. Acetate uptake and subsequent incorporation into sterols and triterpenols decreased substantially in the presence of increasing amounts of sucrose (up to 0.3 M). Traces of acetate did not effect [14C]-sucrose uptake and corresponding synthesis of [14C]-sterols and triterpenols, but increased concentrations of acetate (0.05 M and up) reduced both uptake of sucrose and its conversion into unsaponifiable lipids. The uptake capacity of the cotyledons for [14C]-glycerol exceeded the daily production in the endosperm, but only a small amount of label proceeded to the sterols and triterpenols. [14C]-Triacylglycerols were never detected in the seedling, regardless of the labeled substrate used. Although acetate is an efficient precursor in triterpenol and sterol synthesis, the uptake capacity of the cotyledons for this metabolite is too small in relation to the daily production of water soluble substrates in the endosperem. If acetate is released by the endosperm, only a marginal contribution towards triterpenol and sterol synthesis in the seedling is to be anticipated from this substrate. [ABSTRACT FROM AUTHOR]