Alien versus Predator

Ezine, December 2010

By Dr Roger Day, Deputy Regional Director (Development), CABI Africa

It’s not just in Hollywood movies that aliens are assumed to be the bad guys. This sort of simplistic typecasting goes on all the time in the world of invasive species – and it can be supposedly objective scientists who are responsible. 

Militaristic metaphors are a common way of conceptualizing the invasive species problem and, indeed, many other challenges. Forty years ago, scientists were talking about “the … bombardment of areas of land and sea by alien species”, and a glance through CABI’s recent press coverage shows that military imagery is still the natural recourse for journalists and headline-writers trying to get a scientific story noticed: ’Tiny weapon unleashed on monster weed’; ‘Army of insects to wage war on killer plant’; ‘Japanese bug shipped in to wage war on knotweed’

The use of figurative language is not confined to scientists and journalists. Serious pests often acquire local names. We have come across several named after well known personalities, including Acheampong weed (Chromolaena odorata), Charles Taylor Ant (species unknown) and Osama (Prostephanus truncatus).

In CABI Africa we are working hard to raise public awareness of the problems of invasive species. But it is worth standing back for a moment and considering whether our instinctive use of colourful metaphor is helping or hindering the debate. Warlike imagery implies there are two opposing sides, and that good triumphs over evil. So the ‘war’ can be interpreted as being about good humans triumphing over evil invasives -- clearly a gross simplification, and heavily laden with implicit values. 
 

For a start, it is often man that has enabled the introduction of invasive species. We need to build a sense of responsibility for actions that may have major environmental consequences for others. How can we do that if we are simultaneously casting humans in the role of an innocent hero?

Another  irony is the fact that one of the most cost-effective approaches to reducing the impact of invasives is classical biological control, which entails the intentional introduction of another organism (often from the invasive’s area of origin) that feeds on, preys on or parasitizes the invader. The Kiswahili proverb dawa ya moto ni moto (literally, ‘the medicine for fire is fire’) springs to mind. As does the film Alien versus Predator: in the public imagination, it may be hard to distinguish between the merits of an invasive species and a biocontrol agent, even though biological control nowadays is very safe.

The subject of invasive species is a controversial one amongst the global scientific community, as well as amongst the many publics who stand to gain or lose from the decisions that are made. Although engagement between scientists and publics on invasive species issues (in Africa and throughout the world) is often limited, the range of publics involved, the growing nature of the problem, some high-profile invasions, and links to other public concerns all suggest that it is an area in which public engagement should and will increase. Do we therefore need to find another metaphor?