He initially denied evidence by archaeological findings such as that of Folsom man in 1927 which pushed the date of human presence in the Americas back to more than 10,000 years ago.

After arrival, the promised job brought only a disappointment to his father who started working in a cigar factory along with teenaged Alois to earn a living for the family with six other children.

Young Hrdlička attended evening courses to improve his English, and at the age of 18, he decided to study medicine since he had suffered from tuberculosis and experienced the treatment difficulties of those times.

Between 1898 and 1903, during his scientific travel across America, Hrdlička became the first scientist to spot and document the theory of human colonization of the American continent from east Asia, which he claimed was only some 3,000 years ago.

He argued that the Indians migrated across the Bering Strait from Asia, supporting this theory with detailed field research of skeletal remains as well as studies of the people in Mongolia, Tibet, Siberia, Alaska, and Aleutian Islands.

In January 1913, Hrdlička embarked on an expedition to Lima, Peru, during which he removed 80 trephined and "otherwise highly interesting" skulls from a grave site in the Andes mountain range.

[9][10] Hrdlička was involved in examining a skull to determine that it belonged to Adolph Ruth, who was sensationalized in the press after going missing in Arizona in 1931 searching for the legendary Lost Dutchman's Gold Mine.

[12] Hrdlička's views on race are inspired by those of Georges Cuvier, who in the 19th century argued that there are "only 3 distinct racial stems: The White, The Black, and The Yellow-Brown."

[21] He also threw out the corpse of an infant that was found in a cradleboard but forwarded this artifact along with the skulls and other remains to New York's American Museum of Natural History.

[23] On August 6, 1896, Hrdlička married German-American Marie Stickler (whom he had courted since 1892), daughter of Phillip Jakob Strickler from Edenkoben, Bavaria, who immigrated to Manhattan in 1855.