Zombies have been on my mind lately partly because I’m enjoying “The Last of Us,” the fungus-pandemic horror series on HBO, and partly because of something that showed up in my inbox. Many data tidbits are pushed to me, so they don’t always stop me in my scrolling tracks. But this one did just that. Did you know that more than one in 10 Americans think a zombie apocalypse is inevitable? Among the believers, more than half apparently believe it’s coming in the next 30 years.