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Our current understanding of the complex digestive system of ruminants is mainly based on a few, but intensively studied livestock species. In comparison, information about the anatomy and function of the gastrointestinal tract of wild ruminants is limited. The aim of this thesis was to provide quantitative data on the digestive morphophysiology of the giraffe (Giraffa camelopardalis), the blackbuck (Antilope cervicapra) and the Arabian sand gazelle (Gazella subgutturosa marica). Digestive tract anatomy was characterized by dimensions and weights of the different gastrointestinal tract sections, and digesta samples were collected to describe the digestive function, as indirectly evidenced by the physical characteristics of the digesta. Of particular interest was to determine the presence/absence of rumen content stratification. The findings in each species were then evaluated against available data from other ruminant species, classified as either browsing ‘moose-type’ ruminants or grazing ‘cattle-type’ ruminants. The giraffe digestive morphophysiology generally resembled that of ‘moose-types’ ruminants, showing the same anatomical characteristics and having an unstratified rumen content. One exception was the relatively smaller parotid salivary glands found in giraffes compared to other ‘moose-type’ ruminants. Differences in rumen papillation pattern and fecal particle size between wild and captive giraffes indicate that adjustments should be made to the captive feeding programs. A feeding trial with various silage types revealed a potential for using silage as an alternative forage type. For logistical reasons it was not possible to further investigate this potential, as was originally an aim of the project. The blackbuck digestive morphophysiology generally resembled that of other grazing ruminants (‘cattle-types’), showing the same anatomical characteristics and having a stratified rumen content. One exception was the remarkably smaller omasum observed in blackbucks compared to other ‘cattle-type’ ruminants. The sand gazelle digestive morphophysiology showed both ‘moose-type’ and ‘cattle-type’ characteristics; while some of the characteristics were of an intermediate position between the ranges reported for ‘moose-types’ and ‘cattle-types’. This inconsistency is likely evidence of the sand gazelle being adapted to a diet including both grasses and browse. Overall, all three species investigated deviated in some way from the expectations regarding their digestive tract anatomy and function, thus emphasizing the uncertainty in using a single or a few digestive parameters to predict the feeding style or digestive strategy of a species. The suggested converging digestive morphophysiology of browsing and grazing ruminants do reflect reality, but with several species-specific exceptions. It remains to be investigated if such exceptions can serve to improve our understanding of the functional relevance of a given digestive characteristic, or offer insights into the ecological or phylogenetic history of a certain clade, but it certainly underlines the importance of including phylogeny in investigations of morphophysiological characters. Overall, the findings of this study contribute to a better understanding of the unique digestive strategy of ruminants.

In this paper, we sketch an empirically based theory about how class teaching seems to change in the era of digital media. The research question is: what consequences do access to the Internet have for classroom based teaching? We propose a dialectic process between ‘new conditions’ and ‘school reactions’ running as a deconstruction of the old closed classroom in favour of an open community between students, teachers and third parties. Yet, the deconstruction does not happen at once. Rather, we suggest that it arises through three waves. In the first wave, the old classroom is opened. Students are distracted and teachers do not know what to do. The Internet becomes a challenge to teaching. In the second wave, attention is drawn back to the educational interaction between teachers and students through the use of social media. In this phase, social media are used to re-stabilise the educational situation and intensify it. In the third wave, teachers and students go a step further, succeeding in establishing educationally relevant interaction with third parties (authors, researchers, foreigners, etc.). Only in this final phase does the Internet become a mean of new perspectives that thoroughly alter the old educational setting. In this paper, we sketch an empirically based theory about how class teaching seems to change in the era of digital media. The research question is: what consequences do access to the Internet have for classroom based teaching? We propose a dialectic process between ‘new conditions’ and ‘school reactions’ running as a deconstruction of the old closed classroom in favour of an open community between students, teachers and third parties. Yet, the deconstruction does not happen at once. Rather, we suggest that it arises through three waves. In the first wave, the old classroom is opened. Students are distracted and teachers do not know what to do. The Internet becomes a challenge to teaching. In the second wave, attention is drawn back to the educational interaction between teachers and students through the use of social media. In this phase, social media are used to re-stabilise the educational situation and intensify it. In the third wave, teachers and students go a step further, succeeding in establishing educationally relevant interaction with third parties (authors, researchers, foreigners, etc.). Only in this final phase does the Internet become a mean of new perspectives that thoroughly alter the old educational setting.