Alien Invasion

Venture behind enemy lines on the biodiversity battlefield and weed out the ecological imposters 

- Ella Carter

Aliens are living among us. Humankind cannot escape and we are entirely at their mercy... It may sound like science fiction, but these alien invaders are nothing of the sort. However, they don’t hail from the outer reaches of our universe. In fact, they’re more likely to be found lurking under a rock in your backyard. In biology, an ‘alien’ or invasive species is quite simply one that is thriving somewhere it doesn’t naturally belong.

How these uninvited guests arrive and take hold can happen naturally, or it can be at the hands of us pesky humans. Sometimes the species are transported to their new habitats by mistake, where they hitch a ride on wind or water and get deposited in a new ecosystem. Other times they are introduced by human intervention, perhaps as a solution to another problem without proper knowledge of the species, or as a cute – yet underestimated – novelty that grows into a widespread pest.

As our ancestors began to travel further and further afield, they took plants and animals of all forms along with them for the ride – often unknowingly. In the ocean, larvae of all kinds can be whisked across the planet within ballast water on ships; creatures are transported within goods along trade routes; stowaways in baggage or on clothing can go anywhere in the world just by hopping on a plane with us – the list is endless! But once a species has found an environment in which to thrive, these introductions can have disastrous consequences for populations of native plants and animals.