Open Access

Sandra Engels

• Sandra Engels hat zwischen August 2006 und Juni 2007 Schädel und Gebiß südostasiatischer Ursiden im Hinblick auf Ernährungspräferenzen rekonstruiert. Obwohl die Ursiden systematisch zur Ordnung der Carnivora gehören, verfolgen ihre Vertreter völlig unterschiedliche Ernährungsstrategien. Darunter sind spezialisierte Herbivoren genauso vertreten wie Carnivoren und Omnivoren. Ziel der Arbeit von Sandra Engels war es, anhand der unterschiedlichen Ernährungsregime, Parameter an Schädel, Gebiss und Einzelzähnen rezenter Tiere festzulegen und diese dann auf fossiles Material anzuwenden.
• The family of the Ursidae is numbered among the Carnivora, but the members generally are considered as omnivores. In the eight extant species one can find different feeding strategies and specialisations. Other than five omnivorous species, one herbivore (Ailuropoda melanoleuca), one carnivore (Ursus maritimus) and one insectivore (Melursus ursinus) exist. To define morphological similarities and differences in skull and dentition within the family of the Ursidae, the following method was developed. First the different feeding types are characterized by the parameters that are measured. Furthermore it may be possible to detect food preferences within the omnivorous species. Finally a comparison of fossil with extant tooth material takes place to find similarities and differences between the species in the Plio-Pleistocene and nowadays. Thus morphological features can suggest the type of diet of the fossil animals and the habitat they lived in. Parameters that are measured in the material of the extant species are the distance between occlusal plane and temporomandibular joint, tooth sizes and size ratios as well as shearing edges of the postcanine teeth. The specialized species among the Ursidae all show different values of these characteristics. The herbivore bear shows strong adaptations to masticatory activity such as a large distance between occlusal plane and temporomandibular joint, teeth with a large surface and pronounced shearing edges on the postcanine teeth. The carnivore and the insectivore bear however distinguish from this by a short distance between occlusal plane and temporomandibular joint and smaller teeth in general. The carnivorous member of the Ursidae family possesses generally long, narrow teeth, the insectivorous short and narrow teeth. Furthermore they distinguish by the distribution of shearing edges on the postcanine teeth. Within the omnivorous species tendencies to the one or the other specialist can be found, but in general they are a very heterogeneous group with diverse development of the characteristics, which display hybrids of the specialized forms. The comparison of the fossil material with the extant material shows partial significant differences and tendencies to different values. This may suggest that the measured Plio-Pleistocene species fed partially differently than their relatives living nowadays.