Treseder, K., D.W. Davidson, and J.R. Ehleringer. 1995. Absorption of ant-provided carbon dioxide and nitrogen by Dischidia major (Asclepiadaceae), a tropical epiphyte. Nature 375:137-139.

Although ant-plant mutualistisms have been described in a number of ecosystems, benefits from such relationships have been challenging to quantify. In Bako National Park, Sarawak, Malaysia, stunted 'kerangas' forests occur on nutrient-poor sandstone hills. As trees are widely spaced and have a sparse leaf area, a significant amount of light reaches the tree trunks and enables a diverse community of epiphytes to thrive there. One of these epiphytes, Dischidia major (Vahl) Merr. (Asclepiadaceae), has evolved unusual methods for enhancing carbon and nitrogen acquisition. We show here that a mutualistic relationship exists between ants of the genus Philidris and their host, Dischidia major. Through stable isotope analyses, we calculated that 39% of the carbon in the host plant was derived from ant respiration and that 29% of the host nitrogen was derived from debris deposited into the leaf cavity by ants.