Tyger! Tyger! burning bright in the forests of the night. Immortal though those William Blake lines may be, tigers actually used to go pretty much where they wanted, when they wanted. But new research suggests they've become far more the nocturnal creatures of Blake’s poem.

Why? To keep away from us. Or at least share the landscape with the hairless, upright ape that has ascended to the top of the global food chain—there’s very little we won't hunt down.

In Nepal camera traps have revealed that tigers and humans now walk literally the same paths through the forest—just at different times. Instead of roaming at will any hour of day or night, the tigers of this region have become creatures of darkness. When people retreat from the forest after a day of work, the tiger takes over.

The study was published in Proceedings of the National Academy of Sciences.

Finding such an accommodation is vital if the last 3,000 or so remaining tigers worldwide are to be saved, especially as the world gets even more crowded with people. To save the big cat, we may just need to leave the forest when it's night.

—David Biello

[The above text is a transcript of this podcast.]