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  • Author or Editor: Marcus Clauss x
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Tooth wear can affect body condition, reproductive success and life expectancy. Poor dental health is frequently reported in the zoo literature, and abrasion-dominated tooth wear, which is typical for grazers, has been reported in captive browsing ruminants. The aim of this study was to test if a similar effect is evident in captive rhinoceros species. Dental casts of maxillary cheek teeth of museum specimens of captive black (Diceros bicornis; browser), greater one-horned (Rhinoceros unicornis; intermediate feeder) and white rhinoceroses (Ceratotherium simum; grazer) were analysed using the recently developed extended mesowear method for rhinoceroses. Captive D. bicornis exhibited significantly more abrasion-dominated tooth wear than their free-ranging conspecifics (p<0.001), whereas captive C. simum exhibited significantly less abrasion-dominated tooth wear, particularly in the posterior cusp of the second molar (p=0.005). In R. unicornis, fewer differences were exhibited between free-ranging and captive animals, but tooth wear was highly variable in this species. In both free-ranging and captive D. bicornis, anterior cusps were significantly more abrasiondominated than posterior cusps (p<0.05), which indicates morphological differences between cusps that may represent functional adaptations. By contrast, tooth wear gradients between free-ranging and captive animals differed, which indicates ingesta- specific influences responsible for inter-tooth wear differences. Captive D. bicornis exhibited more homogenous tooth wear than their free-ranging conspecifics, which may be caused by an increase in the absolute dietary abrasiveness and a decrease in relative environmental abrasiveness compared to their freeranging conspecifics. The opposite occurred in C. simum. The results of this study suggest that diets fed to captive browsers are too abrasive, which could result in the premature loss of tooth functionality, leading to reduced food acquisition and processing ability and, consequently, malnourishment.

Open Access
In: Contributions to Zoology
Beiträge aus fachdidaktischer Forschung
Kompetenzorientierung verändert die didaktische Struktur von Lernprozessen - auch im Religionsunterricht.
Der mit der Einführung von Bildungsstandards verbundene Paradigmenwechsel der Bildungs- und Schulpolitik hat auch Konsequenzen für die Religionsdidaktik gehabt. Sowohl für den evangelischen als auch für den katholischen Religions-unterricht gibt es in den meisten Bundesländern in-zwischen kompetenzorientierte Kerncurricula. Auch die wissenschaftliche Religionspädagogik diskutiert seit einigen Jahren intensiv die Frage, in welchem Maße der neue Ansatz der Kompetenz-orientierung die traditionelle Gestalt des Religionsunterrichts verändern wird. Inzwischen liegen Er-gebnisse aus verschiedenen Forschungsprojekten zur Kompetenzorientierung im Religionsunterricht vor. Die vorliegende Publikation präsentiert die jüngsten Forschungsergebnisse und diskutiert die daraus abzuleitenden Konsequenzen für die Gestaltung von religiösen Lern- und Unterrichtsprozessen.

Reducing the size of food particles is crucial for herbivores. Seasonal dietary changes are known to influence animals’ chewing efficiency. Proboscis monkeys (Nasalis larvatus) are foregut fermenters, with a high chewing efficiency allowing them to achieve very fine faecal particles. In this study, we investigated how proboscis monkeys’ chewing efficiency varies between wet and dry seasons, hypothesising differences possibly related to diet change. Faecal particle size analysis is an established approach to estimate chewing efficiency in mammalian herbivores. We analysed 113 proboscis monkey faecal samples collected in the Lower Kinabatangan Wildlife Sanctuary, between 2015 and 2017. By following standard sieve analysis protocols, we measured a mean particle size MPS0.025–8 of 0.45 ± 0.14 mm, and confirmed a previous result that proboscis monkeys have a very low faecal MPS. This study highlights a seasonal influence on proboscis monkeys’ chewing efficiency, with smaller MPS (better chewing efficiency) during the wet season. During that time of the year, individuals may potentially change their diet, as all faecal samples contained intact seeds. Whether the seasonal MPS difference in proboscis monkeys is smaller than in other colobines due to their “rumination” strategy remains to be investigated.

In: Folia Primatologica