Crows are highly intelligent, copy each others behaviour and live abundantly in cities making them the ultimate cleaners of the city. They are capable of collecting cigarette filters on the most difficult places where normal city cleaners can?t reach.The Crowbar is the device developed by a startup called Crowded Cities. It?s designed to train crows to pick up and deposit cigarette butts. A crow drops a cigarette filter onto the device?s funnel, where a camera scans it. After the camera recognizes the item as a filter, it releases a piece of food for the crow to pick up as a reward. The crow then flies off to find more cigarette butts and recruit more crows to participate. www.crowdedcities.com