The map is based on a hypothetical strike that targets nuclear silo sites in Montana, North Dakota, and Nebraska.

Around 1930, an employee with the U.S. Geological Survey simply took a cutout of the map of North America, and balanced ... actually about a hundred miles south, in the town of Robinson ...

A team of researchers has complied a comprehensive list of all known plants that take root throughout North and South America, shedding light on plant diversity and patterns across the two continents.

Here’s how it works. Aside from supercontinent formations, North and South America were unconnected up until several million years ago; then a tiny slat of land linked the continents ...