When they looked at each other's notes, the researchers saw a pattern: For some reason, Czech foxes prefer to jump in a particular direction — toward the northeast. (To be more precise, it's about 20 degrees off "magnetic north" — the "N" on your compass.) As the video above says, most of the time, most foxes miss their targets and emerge covered in snow and (one presumes) a little embarrassed. But when they pointed in that particular northeasterly direction, Ed writes, "they killed on 73 percent of their attacks." If they reversed direction, and jumped exactly the opposite way, they killed 60 percent of the time. But in all other directions — east, south, west, whatever — they sucked. Only 18 percent of those jumps were successful.
Why this preference for a northeasterly/southwesterly leap? Cerveny found that foxes prefer to jump that way regardless of time of day, season of year, cloud cover or wind direction, so the northeast "advantage" isn't a temporary thing. It's constant.
What's going on?
Cerveny believes that foxes have "a magnetic sense." Not only can they see, hear, touch, taste and smell like we do, they've got an extra gift. They can sense the Earth's magnetic field. There are birds, sharks, turtles and ants that can do the same thing. But the fox is the first animal we know of to use this sense to hunt.
Cerveny can't prove this yet; he hasn't found a packet of magnetically sensitive cells or crystals inside a fox. That's going to take time. But if his theory is correct, here's how it might work.