Theories of domestic catâs For decades, many theories have existed to explain the origin of cats. Traditionally, most scholars believed that all domestic cats had a common ancestor in ancient Egypt, where cats were domesticated around 3,600 years ago. Other researchers believed that domestic cats had more than one ancestor, the result of domestication occurring at different times and places, each resulting in a distinct ancestral breed 1.
Railroads usually consider a 100 ft. width of right of way centered about their main track centerline as the minimum on which they can effectively operate. Any encroachment within this limit, even if it is only for ditch cleanout or erosion control, is not welcomed by the railroad and therefore is to be avoided.
4. Shift of Railroad Track from Class I to Short-Line Railroads. Mileage of track roadway owned by Class I railroads (the largest railroads) declined from 164,822 in 1980 to 88,485 in 2000, while the mileage owned by the non-Class I railroads increased from 13,227 to 32,465 during the same period.