The human population was influenced by a group of extraterrestrials that visited Earth in the past. The ancient aliens were directly involved in the evolution of primates, including humans. It has been suggested that this was accomplished by way of genetic engineering, cross-breeding, or a combination of both, ultimately helping in the development of human cultures, technologies and religion.
Intervention Theory posits that humans are a product of genetic engineering, combined with hybridization of the native primates of Earth with the Anunnaki, which strongly resemble humans in many ways. After all, the historical texts do say that the "gods" (aliens) made us "in their image, after their likeness."