Coevolución entre Heliconius y Passiflora: una búsqueda de evidencia desde su distribución geográfica y riqueza de especies

Abstract

The adaptive diversification of plants and their herbivorous insects could be influenced by coevolutionary processes. The biotic relationship between Heliconius butterflies and their host plants Passiflora has been studied from its morphological, physiological, and behavioural aspects. However, whether the degree of geographic correlation between their distributions and richness is informative regarding their coevolution has not been documented. To do this, I modelled the richness and distribution of 165 Passiflora and 34 Heliconius species in Colombia using four different algorithms. In both analyses, the environmental variable that best explains the observed patterns was identified. I compared the distribution pattern between a monophagous species H.eleuchia and its host plants and the oligophagous H.cydno with its 28 host plants. I found that the degree of overlap of Passiflora and Heliconius is low, and its richness is explained by different environmental variables –isothermality on the former and seasonality of precipitation on the latter–. Nevertheless, the most important variable for the distribution of both groups is the annual temperature range. The distribution of H.eleuchia has a higher correlation with its host plants than the distribution of H.cydno, which is consistent with the monophagy and oligophagy of its larvae, respectively. Other ecological factors such as toxicity deserve more attention as potential drivers of coevolution. On a geographical scale, it can be concluded that the pattern of diversification of both genera is likely to be different. Furthermore, since they do not share species richness hotspots, my results are not compatible with a strict coevolution scenario.