Abstract

Until the last decade, the importance of positive relationships among plant species have been underestimated in community ecology, perhaps based on broader perspectives on the individualistic nature of communities (Callaway 1997). However, rapidly accumulating evidence for common and strong facilitative effects in communities (Callaway 1995, Bruno et al. 2003) have led to reconsideration of formal community theory and the rejection of strict individualistic theory by some ecologists (Lortie et al. 2004).