Exposure to an exotic plant seems to have pre-adapted a native Australian lizard to the toxins of an invasive animal.

Credit: T. CHILD

The American cane toad (Rhinella marina), an exotic introduced to Australia within the past century, is generally toxic to native predators. But Richard Shine and his colleagues at the University of Sydney observed that bluetongue skinks (Tiliqua scincoides; pictured) in some areas can tolerate the toad's toxins. The toxins are similar to those produced by another exotic species, the Madagascan 'mother of millions' plant (Bryophyllum spp.).

The authors tested the resistance of skinks from various regions of Australia to either the toad or plant toxin. They found that skinks from areas where the plant is abundant were better able to tolerate both. Moreover, skinks readily eat both the plants and the toads. The findings suggest that the plants have selected for skinks that could tolerate the toad toxins.

Am. Nat. http://dx.doi.org/10.1086/664184 (2012)