Theoretical considerations of eye design allow us to find routes along which the optical structures of eyes may have evolved. If selection constantly favours an increase in the amount of detectable spatial information, a light-sensitive patch will gradually turn into a focused lens eye through continuous small improvements of design. An upper limit for the number of generations required for the complete transformation can be calculated with a minimum of assumptions. Even with a consistently pessimistic approach the time required becomes amazingly short: only a few hundred thousand years.

In higher natural science education, the scientific report is the prevailing genre of writing. Despite the fact that communicative skills are highly valued in working life, earlier studies have shown deficiencies among science students. In this paper, we highlight the need for varied communication training, in particularly arguing for the possibilities that students' popular science writing offers. Our study was based on a questionnaire answered by 64 degree project students in biology. The questions focused on the students' own experiences of writing about their projects for the general public and what contribution the writing made to their learning of science. A vast majority of the students expressed that the writing helped change their perspectives and that they saw their subject and project in a different light. Many of the students described that the popular science writing made it easier for them to put the science content in a context, to better understand the aim of their own work, and the implications of their findings. We discuss the positive effects that popular science writing may have on students' subject matter understanding and development of scientific literacy. Our concluding remark is that popular science writing is a useful tool for reflection and that it adds significant value to the students' capacity to change perspectives, understand their subject and develop scientific literacy.

The composition of the major storage protein, hordein, in wild barley species has been studied by using gel electrophoresis, Coomassie staining, and immunoblot assays. We have shown earlier that it is possible to obtain cross-reaction outside the cultivated barley, with monoclonal antibodies raised against hordeins from the barley cultivar Bomi. These antibodies have now been used to investigate the hordein composition in all species of the Hordeum genus. The results showed that polypeptides similar to the two major hordein groups of cultivated barley, the B- and C-hordeins, are produced in all wild Hordeum species, and that there are both similarities and differences between the two hordein groups. The similarities indicate a common evolutionary origin, while the distinction between B- and C-hordeins in the entire genus clearly shows that the divergence of their coding genes preceded the divergence of the Hordeum species. The presence of the same antigenic site in two different species indicates that they are evolutionarily related. Among the wild species, two rarely occurring sites were exclusively found in H. vulgare ssp. spontaneum and H. bulbosum, which confirms that they are the cultivated barley's closest relatives. Some of the antibodies also gave an extensive reaction pattern with H. murinum, which suggests a fairly close relationship to H. vulgare, though not as close as between H. vulgare and H. bulbosum.

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