The effort to move forward is as difficult as moving backwards. Tar is a trap that, once entered, becomes a life long companion.
Get used to it shit face!
This seepage has been happening for tens of thousands of years. From time to time, the asphalt would form a pool deep enough to trap animals, and the surface would be covered with layers of water, dust, and leaves. Animals would wander in to drink, become trapped, and eventually die.