Ring out the bells, we are being invaded! Niche conservatism in exotic populations of the Yellow Bells, Tecoma stans (Bignoniaceae)

Species invasions are severe drivers of environmental change. Invasive plants may affect soil dynamics, interactions, and ecosystem functioning, leading to environmental and economic losses. Although species invasion success has been explained by niche conservatism, recent studies have demonstrated that niche shifts may also play a key role in this process. In this study, we tested whether niche shift has occurred during the range expansion of the Yellow Bells, Tecoma stans (Bignoniaceae) and predicted its global risk of invasion. We used Reciprocal Ecological Niche Models techniques and multivariate analyses to test our hypothesis and produce a worldwide invasion risk for this species. Niche spaces of African, Australian, and American exotic populations did not differ substantially from the natural one, although the reciprocal models we fitted for exotic and native occurrences poorly predicted each other. The predictions of the models indicated that T. stans is prone to invade new areas where it has not been recorded yet. Given its competitive abilities, preventive programs in prone-to-be-invaded areas are highly recommended.