You may have read not long ago about birds that can plan for the future. The occasion was a paper that came out in the journal Nature detailing some experiments on scrub jays. I found the paper fascinating, not just for the results themselves, but for the many other studies on mental time travel that are going on these days dealing with other animals--rats, pigeons, monkeys, and us. Instead of simply reporting on one experiment, I took some extra time and took a survey of the past and future of mental time travel. It appears in tomorrow's New York Times. For those who crave more, here are some key papers behind the story: **Scrub jays and foresight **Rats and episodic memories **Monkeys and foresight **Episodic memory in humans **The evolution of foresight in humans (pdf, in review) **Brain scans linking past and future (pdf)