In 2018, a new analysis involved genomic sequencing of ancient DNA from mid-fourth-millennium BCE Botai domestic horses, as well as domestic horses from more recent archaeological sites. This allowed for the comparison of these genomes with those of modern domestic and Przewalski's horses. The study revealed that Przewalski's horses not only belonged to the same genetic lineage as those from the Botai culture, but may be the feral descendants of these ancient domestic animals, rather than representing a surviving population of never-domesticated horses. Having been domesticated for a relatively short time (and having become feral soon after), the Przewalski's horse retained more wild or primitive traits than did other horses. The Botai horses were found to have negligible genetic contribution to any of the other ancient or modern domestic horses studied, indicating that these horses arose from an independent domestication involving a different wild population.