Yes, the robots are definitely coming for the jobs of America's 3.5 million cashiers. Just ask the retail workers who've already been displaced by automated checkout machines. Robots may also be coming for radiologists, whose expertise diagnosing diseases through X-rays and MRIs is facing stiff competition from artificial intelligence. And robots are starting to do some of the work in professions as diverse as chef, office clerk and tractor-trailer operator. For most of us, though, the robot invasion will simply change the tasks we do, not destroy our jobs altogether.

The following is an excerpt from GigaOm publisher Byron Reese's new book, The Fourth Age: Smart Robots, Conscious Computers, and the Future of Humanity. You can purchase the book here. The Fourth Age explores the implications of automation and AI on humanity, and has been described by Ethernet inventor and 3Com founder Bob Metcalfe as framing "the deepest questions of our time in clear language that invites the reader to make their own choices. Using 100,000 years of human history as his guide, he explores the issues around artificial general intelligence, robots, consciousness, automation, the end of work, abundance, and immortality." When the topic of automation and AI comes up, one of the chief concerns is always technology's potential impact on jobs.

A robot has just moved into the cubicle next to you, and you're wondering whether it will soon take your place. Experts say humans are better at jobs that require empathy, creativity or physical dexterity than our robot competitors. For instance, in the graphs above, empathetic nurses, creative CEOs and dextrous tree pruners are all on the low end when it comes to automatability, as measured by McKinsey. These core characteristics may determine how resistant a job is to automation more than pay, industry sector or skill level. Automatability is just a number.