Animals have don't need passports or visas, and they don't care about countries' borders — and that's vividly illustrated by this animated globe.
It shows migration routes for about 150 species based on tracking data shared by over 11,000 researchers from around the world. The pink lines follow the movement of animals covering at least 310 miles in one direction for at least 45 days, combining about 8,000 tracks collected over a period of about 10 years. You can see lines extend from Africa to Turkey, all the way up to Europe, as well as from Canada to the United States, and vice versa.
Tracking devices have been used by scientists for a long time to study how animals move within local regions and migrate across oceans and continents. In the past, scientists used to tie bands around birds' legs or use radio transmitters. Today, trackers and tags use GPS and satellites to record data down to the second. The information can help us understand how animals hunt, how they are responding to climate change, or habitat fragmentation — or even just why baby sharks hang out at LA beaches.