Free Republic

The idea seemed too crazy to Rod Simmons, a measured, careful field botanist. Naturalists in Arlington County couldn't find any acorns. None. No hickory nuts, either. Then he went out to look for himself. He came up with nothing. Nothing crunched underfoot. Nothing hit him on the head. Then calls started coming in about crazy squirrels. Starving, skinny squirrels eating garbage, inhaling bird feed, greedily demolishing pumpkins. Squirrels boldly scampering into the road. And a lot more calls about squirrel roadkill. But Simmons really got spooked when he was teaching a class on identifying oak and hickory trees late last...

For years, conservationists have been concerned about the impact of invasive plant species in the Galápagos Islands. Hundreds of species have been identified as being nonnative, introduced through human contact. The idea is to remove these plants to help keep the archipelago ecologically pristine. That’s a worthy goal. But there’s just one problem, according to a study in Science: some of these pariah plants turn out to be native after all. They predate humans in the Galápagos by thousands of years. The evidence for this is in the form of fossilized pollen grains found in sediment cores from bogs on...

When Hurricane Andrew hit Florida in 1992, no one gave much thought to the six exotic lionfish that spilt into Biscayne Bay as the storm smashed their Miami waterfront aquarium. Sixteen years later, thousands of the fish are wreaking havoc off America's east coast, leading a potentially catastrophic marine invasion. The highly poisonous hunter-killer, which is normally found in the Pacific and Indian Oceans, is the first non-native fish to establish itself in the Atlantic, where it is eating its way through other species faster than they can breed. “They are eating almost anything that fits in their mouths,” said...