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IT started out 50 years ago as an alternative to buttons and zips on outdoor clothing. Today Velcro is used everywhere a good grip is needed. The material is ubiquitous. Where cars once had rivets and bolts, they now have Velcro. A short strip of the stuff held together the ventricles of the first artificial heart. It even has a place in space, where shuttle astronauts keep their ship tidy by anchoring bits of gear to patches on the wall. Yet by a strange twist that its inventor could never have foreseen, Australian botanists have discovered that Velcro’s very effectiveness is posing a threat to the planet’s most pristine places.

How so? Jennie Whinam, a botanist with Australia’s Department of Primary Industries in Tasmania, and colleagues from the Australian Antarctic Division decided to check what sort of alien organisms might be hitching a ride on the division’s expeditions to remote sub-Antarctic islands. They inspected scientists and support staff arriving at Macquarie Island, using vacuum cleaners and forceps to suck and pluck every seed, spore and plant fragment from their clothing and equipment. Of the 64 arrivals, only 20 were clean. The others had brought with them a motley collection of 981 seeds and fruits belonging to 90 species, some of them invasive and a serious risk to the local flora. While some seeds lurked in pockets, cuffs and seams, woolly socks and boots, the vast majority came attached to the Velcro fastenings of clothing and gear (Biological Conservation, vol 121, p 207).

There’s a fine irony to this. The Swiss inventor of the original material, Georges de Mestral, came up with the idea in 1948 after walking his dog and finding dozens of prickly burrs entangled in its coat. Why were they so hard to remove? He found the answer under a microscope: the fine hooks covering the burr, seed heads of the mountain thistle, had become so enmeshed in the dog’s hair the two were almost impossible to separate. This, of course, is just what nature intended for the wide dispersal of seeds. Some years later Mestral produced his fastener, whose name is an abbreviation of velours (the fuzzy part) and crochet (the hooked part).

Now Mestral’s invention appears to be doing a good job of carrying seeds over long distances. That’s extremely worrying because the spread of alien species to foreign lands is second only to habitat loss as a cause of disappearing biodiversity. Australia has introduced stringent measures to prevent its researchers accidentally wrecking the places they have gone to study. But, as Whinam points out, travellers are increasingly adventurous, and those who seek out the planet’s most pristine places are also likely to hop from continent to continent in their search. They should be aware that the seeds of destruction may be hitching a ride.