|Hall, Mary Beth|
|O'driscoll Worman, C.|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/1/2006
Publication Date: 10/15/2006
Citation: Danish, L., C. A. Chapman, M. B. Hall, K. D. Rode, and C. O'Driscoll Worman. 2006. The role of sugar in diet selectin in redtail and red colobus monkeys. In: Hohman, G., Robbins, M. M., Boesch, C., editors. Feeding Ecology in Apes and Other Primates. Cambridge, UK: Cambridge University Press. p. 473-487. Interpretive Summary: Preventing extinction of animals in the wild often depends on maintaining their habitat on which they rely for food and a place to live. Populations of animals are more likely to survive if food supplies and associated habitat crucial to meeting their nutrient needs can be maintained. If we wish to prevent extinctions, understanding habitat needs, including how the animals' nutritional needs are met by the feeds they choose and the extent of habitat needed to grow those feeds can provide a basis for making informed decisions about habitat conservation to preserve species. A study of diet selection by redtail and colobine monkeys in the wild was carried out to assess whether the different species differed in the sugar content of the feeds they selected and consumed. It had been proposed that colobine monkeys that rely on fermentation to digest feeds would select feeds lower in sugar than would redtail monkeys that do not rely on fermentation to digest feeds. The fruits and leaves selected by both types of monkeys did not differ in their sugar contents, and sugar comprised a significant part of the diets of both species. However, neither type of monkey appeared to select foods based on their sugar content. These results contradict accepted ideas about the role of sugars in the diets of monkeys that do or do not rely on fermentation as part of digestion. It does suggest that a diversity of feedstuffs must be maintained to meet the nutritional needs of these species.
Technical Abstract: A study of diet selection by folivorous (red colobine monkeys; Piliocolobus tephrosceles) and frugivorous (redtail monkeys; Ceropithecus ascanius) was performed to provide comparable compositional descriptions of the diets of the two species, to contrast sugar content of plant foods consumed by each species, and to evaluate if either of the species was apparently selecting for or against food items based on their sugar content. It had been hypothesized that monkeys with pregastric fermentation such as the colobines would avoid or limit intake of feedstuffs with high sugar contents to avoid perturbation of the pregastric fermentation with excessive organic acid production, whereas monkeys such as redtails that lack pregastric fermentation would select for feeds with greater sugar content to increase digestible energy intake. There was no correlation between foraging effort and sugar content of the foods consumed. The average sugar content of fruits selected for consumption (14.9% of dry matter) was greater than that of leaves selected (8.1% of dry matter), however, the respective sugar contents of leaves and fruits consumed by the two primate species did not differ. The results of this study contradict the accepted idea that high levels of sugar cannot be consumed by primates with fermentative digestive systems.