We are not alone - quite literally. According to United Nations (UN) projections, the population of this giant rotating ball called Earth will hit a key milestone next week.
On November 15, the world's population is projected to reach 8 billion. What does the milestone mean for us humans, and, more importantly, the planet?
Dr Robert Bartholomew is a sociologist and senior honorary lecturer at the University of Auckland, and talks to Karyn Hay.
Photo: Visible Earth, NASA/JOHAN SWANEPOEL/SCIENCE PHOTO LIBRARY
