Researchers set up two obstacle courses that followed a grid and non-grid pattern (right, above). The paths the rats took in both courses covers the same distance, but in the grid "city," rats' paths covered much more territory than in the irregular "city."
Quoting from the Science Daily article,
"We've found that routes taken by rats and other members of the animal kingdom tend to converge at attractive landmarks, the same way people are attracted, for example, to the Arc de Triumph in Paris," says Prof. David Eilam from TAU’s Department of Zoology.The researchers also hope that rat race experiments like this one might be of some use to urban designers as they plan new cities and neighborhoods in the future.
Speaking of rats' love of Manhattan, New York City's Pest Control Services is now indexing their inspection reports on online maps at the new Rat Information Portal, which allows anyone to compare rat inspection data across neighborhoods, community districts, or individual properties. Below, a map of rat inspection results in the Upper East Side. Red parcels indicate properties where inspections found "signs of rats," orange parcels indicate "problem conditions" (such as exposed piles of garbage), and yellow parcels indicate properties that passed their initial inspections: