Search

Several letters to the editor are presented in response to the article on overtaking in motorcycle racing, television coverage of bike racing, and testimonial section for county courts on a website.

Hyalella azteca, in common with other amphipods, exhibits precopulatory pairing, when the male carries the female beneath his ventral surface for several days until she moults, and so ensures successful sexual contact during the post ecdysis period when mating can occur. Although animal courtship is a ritualist behaviour, for some groups there is clear evidence that mating behaviour and mate selection are dependant upon and can be influenced by experiences and learning during early development stages. This study was designed to examine the effect of social isolation, during neonatal development, on the success of H. azteca in forming precopula pairs for the first time. The results demonstrated that animals reared in isolation and so deprived of physical, visual and chemical exposure to conspecifics formed precopula pairs at the same developmental time and with the same frequency as animals which had been reared together with their conspecifics.

1. A light and scanning electron microscopic study of the structure of epilithic diatom communities was carried out at two sites on the River Taff, South Wales, an upstream unpolluted site (Site 1) and a downstream polluted site (Site 2). 2. Community structure at the micro-scale revealed that, although communities at both sites were similar in terms of species present (similarity indices ranging between 0.44 and 0.96), they were very different with respect to their physical structure. 3. The traditional approach in studying epilithic diatom communities ignores information relating to community structure. The combination of light and scanning electron microscopy proved to be most useful for studying the epilithic diatom communities. 4. The examination of community succession on stone substrata showed that communities were highly dynamic on a weekly time scale, which suggests that the “age” of a substratum is a very important determinant of the attaching communities. A change from a prostate, two-dimensional community structure to an erect, three-dimensional community structure, and a shift from the dominance of epilithic diatoms to the dominance of epiphytic diatoms were noted. Such a change was more noticed at the polluted downstream site, possibly due to a higher rate of surface pre-conditioning and biofilm production at this site than at the unpolluted upstream site.

Several letters to the editor are presented in response to articles in previous issues including one about riding a Ducati Panigale by John Howie in a 2013 issue, an article about the Yamaha Thunderace motorcycle, and one about the Ducati 250.