Brightly-coloured insects may provide clue to potential anti-cancer compounds

In collaboration with the Press Association

Brightly-coloured beetles and butterfly larvae could help scientists to identify plants that have compounds with anti-cancer activity, experts in Panama have found.

Described as "incredibly exciting and important" by project director Todd Capson, the finding could speed up the discovery of new drugs by facilitating the search for medicinally active plants.

Researchers at Smithsonian's Tropical Research Institute (STRI) in Panama studied three groups of plants - one which was known to have anti-cancer compounds; another with compounds that were active against disease-carrying parasites; and a third with no medicinal activity.

They found that insects with bright warning colours were much more likely to feed on plants with anti-cancer or anti-malarial compounds than on plants with no such compounds.

In contrast, plain-coloured insects showed no particular preference for any of the plants.

Researcher Julie Helson said that the team had simply "put two and two together".

"We knew that brightly coloured insects advertise to their predators that they taste bad and that some get their toxins from their host plants. But because other insects cheat by mimicking the toxic ones, we weren't sure if insect colour was really going to work to identify plants containing toxins - it did!"

The study is published in the journal Frontiers in Ecology and the Environment and suggests that scientists may be able to speed up their search for anti-cancer compounds simply by screening different tropical plants for the number of brightly-coloured insects feeding on them.

Mr Capson, who is a research chemist at the STRI, said: "The results of this study could have direct and positive impacts on the future of medical treatment for many diseases around the world.

"I am hopeful that other investigators will follow our lead and test our theory that insects can lead us to plants with disease-fighting properties."