Plant Chemistry and the Evolution of Host Specificity: New Evidence from Heliconius and Passiflora

Science  25 Aug 1978:
Vol. 201, Issue 4357, pp. 745-747
DOI: 10.1126/science.201.4357.745


Larval growth rates of Heliconius butterflies do not closely parallel host plant choice, an indication that factors other than host plant chemistry are important in evolving host specificity. High growth rate in one species is correlated with reduction in number of palatable host species. This suggests a mechanism by which ecologically restricted species become progressively biochemically specialized.