Fleshy fruits are typically coloured either red or black and are displayed in conspicuous locations where they can be easily located by birds. However, fleshy fruits in New Zealand are often white or translucently coloured and are displayed in the inner recesses of plant canopies. These characteristics have been attributed to coevolution with reptiles. I describe seed dispersal by a ground weta in Nelson lakes National Park, and hypothesise that the unusual characteristics of fleshy fruits in New Zealand may result from coevolution with weta.
This study examined how forest edges, fruit display size, and fruit colour influenced rates of seed dispersal in an endemic, bird-dispersed, New Zealand mistletoe species, Alepis flavida. To examine rates of seed dispersal, fruit removal rates were compared between plants growing on forest edges and in forest interior, and also between two morphs of plants with different coloured fruits. Two aspects of fruit display size were examined: plant size and the neighbourhood of conspecific plants.
Both tree and ground wētā have been proposed as potential seed dispersers of some New Zealand fruit. We examine evidence for coevolution of ground wētā and fleshy fruits as suggested by Burns (2006). We found that although ground wētā consume fruits from Gaultheria depressa and G. antipoda, they do not do so in a way that would suggest they had coevolved as dispersers with these or other New Zealand plants (Coprosma, Muehlenbeckia, Leucopogon).