For eons, coyotes roamed what is now the western United States, with its wide-open plains. Then came European settlers, who cut down forests for farms and ranches in a steady east-west march. Along the way, they killed large predators such as pumas and wolves to protect livestock and for their own safety.
The predators they obliterated were mortal enemies of the coyote, holding them in check, a new study in the journal ZooKeys says. As mountain lions and wolf packs disappeared from the landscape, coyotes took advantage, starting a wide expansion eastward at the turn of the last century into deforested land that continues today.