Without ants to bite them, the elephants rip up the thorn trees, opening up the grassland, which makes it harder for lions to catch their preferred zebra meals. Lions end up hunting buffalo instead.

Young female (left) and male lions stalk prey within a “pristine” (uninvaded) savanna. The whistling-thorn trees in the foreground provide cover used by lions to stalk and ambush plains zebra.

We now see they are transforming landscapes in very subtle ways but with devastating effects," Palmer said. It all starts with the whistling-thorn acacia trees in the plains of Laikipia, Kenya.