Date: March 26, 2018
Source: University of California - Santa Barbara
Summary:
Forty million miles of major
roads crisscross the Earth's continents -- enough to circle the planet 1,600
times. For humans, these thoroughfares are a boon, enabling them to move with
ease from place to place. But for migrating animals who are also hemmed in by
dams, rivers, shipping lanes, urban development and agriculture, they create
another barrier.
