2 days after people, In New York City, horses used by the NYPD and to pull Central Park carriages now roam the urban jungle, scavenging from garbage cans. Will they be able to survive without their human caretakers?
3 years after people, The horses have fled New York City and now graze off suburban yards and golf courses.
50 years after people, The horses lose all traces of their domestication.
10,000 years after people, Due to the growth of forests the New York City horses moved to the beaches of Long Island. Now 10,000 years later their descendants still roam the beaches. The high salt content in their food supply means they have to drink twice as much as their ancestors did and, because of the lack of nutrients available, they have also evolved to be much smaller than their ancestors, but they survive. The horses elsewhere still thrive.