Abstract

The gross morphology of the body and gastrointestinal tract of genetically-similar tammar wallabies (Macropus eugenii) that had been introduced into two different nutritional environments on the North Island of New Zealand were compared using multivariate analysis. Tammar wallabies from Kawau Island had significantly lower body mass per unit body length than those from the Rotorua district where food was more abundant. Furthermore, wallabies from Kawau Island had longer small intestines and caecae relative to other gut regions than did those from the Rotorua district. This suggests that poor-quality food might reduce the efficiency of primary fermentation in the forestomach; similarly, the efficiency of digestion and absorption in the small intestine might be reduced. In addition, poor-quality food might promote secondary fermentation in the hindgut of grazing tammar wallabies.