Forests may be known as the lungs of the Earth but one in the Canadian province of Nova Scotia is causing a stir for being a rather more literal example of that.
Brian Nuttall was out walking on a windy autumn day in Apple River, Cumberland County, when he noticed a rather unusual phenomenon.
The ground appeared to be heaving in and out, in a regular rythmn, in time with the wind. He pulled out his phone and started filming it.
His video has led to a lot of online speculation as to the cause.
Some say it is a sink hole while others suggest it is a stream under the ground.
However, what's really going on is more straight forward. Tree roots, spread out wide underneath the forest floor have detached from their moorings.
The root systems heave under the ground when the trees are caught by wind, making them appear to 'breathe.'