
In the 1930s a handful of cane toads were released on Australian sugar farms to eat a beetle they turned out to be unable to reach, and from roughly 100 animals they have since bred into well over 200 million, spreading west across the continent faster each year.
A failed pest-control experiment in 1930s Queensland released an amphibian that became far more destructive than the beetle it was meant to kill, and continues its relentless march across Australia today.














