Friend or foe?
HUMANS have been transporting species around the world, intentionally and unintentionally, for centuries. Many of the species we think of as a natural part of our landscape are, in fact, non-native. For example, the honeybee, which nearly a third of US states have named as their state insect, was introduced into North America from Europe in the 1600s.
Naturalists have long been aware of this bio-globalisation, but widespread research on introduced species did not begin until the early 1980s. In those days, the message from invasion biologists was clear and simple: introduced species were bad news. They…
