They faced constant hazards from storms, floods, Indians, and those who would steal the herds. The trickle that had begun in 1846 became a flood, as over 10,000,000 cattle were sent over the northern trails before they were closed. More than 700,000 cattle were driven north in 1871, the year of maximum effort. The trail herds of the 1860s and 70s probably averaged 2,000 to 2,500 cattle. The cowboys received an average of one dollar per day and with the traveling rate of 10 to 12 miles per day, were on the trail for a minimum of two months.
Nature produces animals that all possess a single common denominator, environmental adaptability.
It is this common denominator that is sometimes called survival of the fittest. The evolutionary process created a breed of cattle that had a body size commensurate with the availability of food, a breed of cattle that developed horns for protection, allowing the dominate males to propagate the breed. Polled or non-horned cattle did not survive. In the space of only four generations, the traits that had evolved through decades of natural selection of Texas longhorns under range conditions began their swift decline into obscurity. Thus, the development and maintenance of a once proud breed was placed in the hands of the federal government at the Wichita Mountains Wildlife Refuge near Cache, Oklahoma.