Record Details

Adsersen, Anne;Adsersen, Henning
Cyanogenic plants in the Galápagos Islands: ecological and evolutionary aspects
Journal Article
Conolophus subcristatus
A representative part (65%) of the indigenous Galapagos flora was screened for contents of cyanogenic compounds by incubation of fresh crushed leaf material with P-glucuronidase and by analysis of released HCN. Most species with HCN development (cyanogenic species) were subsequently incubated with pure water to test for contents of glycosidases in the leaf. Plants with positive reaction were termed cyanophoric. The endemic part of the flora proved to have a higher percentage of cyanogenic and cyanophoric plants than the native part. The absence of mammalian leaf herbivores in the herbivore regime made us assume that cyanogenic compounds would be redundant. The results contrast this. If the observed pattern is a result of folivore selection, reptiles, insects and/or snails must be responsible. The impact of cyanogenic and cyanophoric leaves on herbivores is discussed in relation to selection.