Humans have had a profound effect on the world.

Since we first emerged almost 200,000 years ago we have spread across the globe with a speed like no other animal on earth.

While we are only now beginning to fully grasp the gravity of our actions and activities on the environments and ecosystems we share  - what if it wasn't our actions but the very sound of our voice which affected the way animals behave?

Justin Suraci, an Ecologist in the Environmental Studies Department at the University of California, Santa Cruz set out to better understand how humans create an apparent 'Landscape of Fear' and why we are the predators that other apex predators fear the most.