Around 1730 Cheyenne people introduced the Lakota to horses, which they called "šuŋkawakaŋ" ("dog power/mystery/wonder"). After they adopted horse culture, Lakota society centered on the buffalo hunt on horseback. The total population of the Sioux (Lakota, Santee, Yankton, and Yanktonai) was estimated at 28,000 by French explorers in 1660. The Lakota population was estimated at 8,500 in 1805, growing steadily and reaching 16,110 in 1881, one of the few Native American tribes to increase in population in the 19th century. The number of Lakota expanded to more than 170,000 in 2010, of whom about 2,000 still speak the Lakota language ("Lakȟótiyapi").