To be fair to Kant, it does have something to do with Kant. Kant's thesis of innate mental categories was pretty radical in its time, and certainly wasn't obvious. Now we know there are quite a few innate mental categories, due to our evolutionary history. But we didn't know Kant was right about a few particular cases until after the science had been done, and Kant was wrong about almost everything else. :)
Our "innate mental categories" and Kant's are by no means the same. He believed that the categories are innate because they refer to a meaning beyond ourselves (in other words, that we process Euclidean geometry because space is Euclidean, and we contain the seeds of something that Knows this without evidence). We, upon discovering an innate mental category, can file it among "things to exploit or fix".
That rats have a grid prior to experience is unsurprising. They derive more evolutionary benefit from such a heuristic than from having to lug aroudn an expanded brain capable of inventing geometry.
I've often wished for a list of cases where philosophy has proven useful, or has at least anticipated science in drawing correct conclusions. Here's one for the list:
The June 18 2010 Science has two very similar articles on how rat brains represent space. Both conclude that the brain already represents space as a grid before rat pups take their first steps into the world. Both make the point that this validates Kant's claim that space is an innate concept prior to experience.
(The next task is to make a corresponding list of cases where philosophers made incorrect conclusions; and estimate whether the number of correct conclusions is greater than chance.)