Among the many obligations keeping me away from the blog is the nearly-completed overhaul of my web site, carlzimmer.com. Along with information on my books and talks, the site also has an archive of the past few years of my articles. I’ve made my way back to 2001, and I am continuing to push back further. It’s a strange experience to look back over many dozens of stories that all seemed rather cutting-edge at the time. In some cases, they’ve been outstripped so starkly by later research that they seem almost like time capsules now. In other cases, further research hasn’t really pushed the boundary of knowledge much more.

Here is a selection of pieces, one a