Ebola’s evolutionary beginnings are more ancient than initially thought, a new study finds. Scientists say that the family of viruses, including Ebola and Marburg, is ancient, and the two viruses shared a common ancestor millions of years ago. According to the research, filoviruses, the family containing Ebola and Marburg, another deadly relative, is at least 16 to 23 million years old.

It is believed that filoviruses were likely found in the Miocene Epoch. According to the study, during this time, the evolutionary lines that link Ebola and Marburg had already diverged.

The research was published in September in the journal Peer J. The new study enhances scientists’ growing knowledge regarding known filoviruses, which experts think once came into being around 10,000 years ago, coinciding with the increase in agriculture. The new study places the family’s age in the same time span when great apes arose.

Lead researcher Derek Taylor, PhD, professor of biological sciences at the University of Buffalo, said in a statement, “Filoviruses are far more ancient than previously thought.” He continued, “These things have been interacting with mammals for a long time, several million years.”

Instead of addressing the present-day Ebolavirus, the research indicates that Ebola and Marburg both come from ancient evolutionary lines and that the two viruses previously shared a common ancestor at some point prior to 16 to 23 million years ago.

According to the World Health Organization, the Ebola Virus was first discovered in 1976, when it first appeared in two simultaneous outbreaks, one in Nzara, Sudan, and the other in Yambuku, Democratic Republic of Congo.