Forests with trees that walk and hunt

There's a tree in the Ecuadorian rainforest that locals swear moves a few centimetres each year, chasing the sunlight.

It's called Socratea exorrhiza — the walking palm. Instead of one buried trunk, its base splits into a cone of stilt roots that lift it half a metre off the forest floor. New roots grow on the sunny side. Old roots on the shaded side die back and rot away. Over months and years, the tree, in theory, drifts.

Botanists are split on whether this is real. A 1980 paper claimed walking palms can travel up to 20 metres in their lifetime. A 2005 study walked it back, arguing the roots are structural, not locomotive, and that the tree stays exactly where it sprouted. The argument has never fully resolved. Local Quechua and Sápara guides, who walk those forests every day, insist the trees move. Visiting biologists, who don't, mostly insist they don't.

Either way, the stilt roots are real and they are doing something strange. They let the palm sprout on top of a fallen log, then "step off" it as the log decays — placing itself on solid soil years later, several metres from where it started. They let it survive shallow landslides that would topple any normal trunk. They give it a tripod stance steady enough to hold up a thirty-metre canopy in waterlogged ground.

There's also a tree in New Zealand, the northern rata, that begins life perched in another tree's branches and slowly lowers strangling roots to the ground over a century, eventually killing its host and standing where the host once stood.

A forest you thought was still is, on the long view, very slowly rearranging itself.