Marsha Barkley, age 11, of Des Moines, Iowa, for her question:

Why were rabbits taken to Australia?

To the settlers from England, Australia was a home away from home. Like the American pioneers, they brought samples of everything they could from the Old World they had left behind. Rabbits were unknown in Australia, so some were taken along  no doubt to make the place seem more homey. Then in 1$59, 24 of these European rabbits were set free to make a go of it in the wild. And my, how they multiplied!

Since there were no native rabbits, naturally there were no native animals that feed on rabbits. The newcomers thrived on the grasses and had no natural enemies to keep down their population explosions. In a few years, their teeming hordes were stripping the plains bare and doing hundreds of million dollars worth of damage to the sheep ranches. Foxes were brought in to reduce the rabbit plague and they too became a plague. In 1950, a rabbit disease was introduced. It helped, but some strains became immune and survived.