Hope Not Hype - Third World Network

Appendix Two: The Indirect Benefits of Genetic Engineering are Not Sustainable
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associated with the bi-directional flow of genes between crop and sexually compatible
weeds (Heinemann, 2007). Weed plants that also could extend their vigour under these
conditions would have the potential to persist and invade non-agricultural lands that
currently are inhospitable to these plants (Heinemann, 2008).
[New transgenic] traits such as stress-tolerance may increase competitive ability allowing
the species to invade into natural habitats and/or replace natural or agricultural communities
by expanding plantings into regions where the crop previously could not grow. For example,
if aluminium-tolerant crops could be planted on a large scale in high aluminium, acidic
soils, such as savannas or cleared rainforests, this may reduce biodiversity or endanger or
eliminate the original communities. This might be particularly devastating in savannas, such
as the Brazilian cerrado, because they often sustain a high biodiversity (Andow and Zwahlen,
2006, p. 208).
That kind of invasion could have severe environmental consequences.
Biological invasions are believed to be the second largest cause of current biodiversity loss,
after habitat destruction (Keane and Crawley, 2002, p. 164).
The estimated cost of biological invasions in just six countries – the US, the UK,
Australia, South Africa, India, and Brazil – is US$314 billion (Pimentel et al., 2001).