A much smaller number of people are insensitive to pain due to an inborn abnormality of the nervous system, known as "congenital insensitivity to pain". Children with this condition incur carelessly-repeated damage to their tongues, eyes, joints, skin, and muscles. Some die before adulthood, and others have a reduced life expectancy.[citation needed] Most people with congenital insensitivity to pain have one of five hereditary sensory and autonomic neuropathies (which includes familial dysautonomia and congenital insensitivity to pain with anhidrosis). These conditions feature decreased sensitivity to pain together with other neurological abnormalities, particularly of the autonomic nervous system. A very rare syndrome with isolated congenital insensitivity to pain has been linked with mutations in the SCN9A gene, which codes for a sodium channel (Nav1.7) necessary in conducting pain nerve stimuli.
What is it known as when someone is born without being able to feel pain because of their nervous system?
congenital insensitivity to pain

Antarctica continued to become more isolated and finally developed a permanent ice cap. Mountain building in western North America continued, and the Alps started to rise in Europe as the African plate continued to push north into the Eurasian plate, isolating the remnants of Tethys Sea. A brief marine incursion marks the early Oligocene in Europe. There appears to have been a land bridge in the early Oligocene between North America and Europe since the faunas of the two regions are very similar. During the Oligocene, South America was finally detached from Antarctica and drifted north toward North America. It also allowed the Antarctic Circumpolar Current to flow, rapidly cooling the continent.
In the Oligocene period South America broke free from what other continent?
Antarctica

Tracks of the Northern Pacific Railroad (NPR) reached Montana from the west in 1881 and from the east in 1882. However, the railroad played a major role in sparking tensions with Native American tribes in the 1870s. Jay Cooke, the NPR president launched major surveys into the Yellowstone valley in 1871, 1872 and 1873 which were challenged forcefully by the Sioux under chief Sitting Bull. These clashes, in part, contributed to the Panic of 1873 which delayed construction of the railroad into Montana. Surveys in 1874, 1875 and 1876 helped spark the Great Sioux War of 1876. The transcontinental NPR was completed on September 8, 1883, at Gold Creek.
When did the Northern Pacific Railroad reach Montana from the east?
1882