Il paraît qu’à Moscou où vivent près de 35 000 chiens errants (1 pour 300 habitants) quelques uns de ces chiens ont adopté un comportement de comuters, prenant le métro pour aller de leurs lieux de résidence dans les banlieues aux endroits où ils savent trouver de la nourriture, et retour. Un remarquable cas d’adaptation au milieu.
The Moscow Metro is the second most heavily used in the world by daily ridership. About 500 dogs on average live in its stations, especially during colder months. Of thèse dogs, about 20 are believed to have learned how to use the system as a means of commuting. The strays move to the city center during the day in search of food and return to the suburbs at night.
Theories to explain how they are able to correctly determine their routes include: an ability to judge the length of time spent on the train in between stations/time intervals recognition of the place names announced over their train's loudspeaker the scents of particular stations a combination of such factors. They are said to prefer the quieter, less trafficked cars at the very front or back of the train. Author Eugene Linden, a specialist in the subject of animal intelligence, believes the dogs' behavior exhibits "flexible open-ended reasoning and conscious thought".