According to an international team of researchers led by Dr. Yohannes Haile-Selassie of The Cleveland Museum of Natural History, the Australopithecus “Lucy” was not alone in the region that is now Ethiopia. The researchers claim to have found conclusive evidence that at least one other human ancestor species roamed the same area at the same time.

The upper and lower jaw fossils Woranso-Mille area of the Afar region of Ethiopia were found 22 miles north of “Lucy’s” site and belong to the newly described species Australopithecus deyiremeda. According to the researchers, the size and shape of the teeth as well as the architecture of the lower jaw clearly differentiate the specimen from Lucy’s species.

According to the researchers dating, the owner of the bones wandered Ethiopia between 3.3 and 3.5 million years ago. Lucy’s species roamed roughly the same area between 2.9 and 3.8 million years ago, indicating that the species co-existed for at least part of that time.

“The age of the new fossils is very well constrained by the regional geology, radiometric dating, and new paleomagnetic data,” said Dr. Beverly Saylor in a statement.

Saylor of Case Western Reserve University is co-author of the paper published in the May 28, 2015 issue of the journal Nature.

It has long been believed that the evolution of modern humans happened in a straight line, with one species being replaced by the next. It is, however, becoming more and more apparent that there were at least two species and possibly more living in Africa during this time period.

“The new species is yet another confirmation that Lucy’s species, Australopithecus afarensis, was not the only potential human ancestor species that roamed in what is now the Afar region of Ethiopia during the middle Pliocene. Current fossil evidence from the Woranso-Mille study area clearly shows that there were at least two, if not three, early human species living at the same time and in close geographic proximity,” said Haile-Selassie.

Two other suspected primitive human species were found in Africa in the late 90s. Australopithecus bahrelghazali was discovered in Chad in 1995 and was dated at 3.6 million years ago. Kenyanthropus platyops was discovered in Kenya in 1999 and is dated to 3.2 to 3.5 million years ago. Both of these discoveries have their skeptics, and this latest find is expected to as well. However, it is becoming increasingly clear that 3-4 million years ago in Africa, there was more than one pre-human species.

“This new species from Ethiopia takes the ongoing debate on early hominin diversity to another level. Some of our colleagues are going to be skeptical about this new species, which is not unusual. However, I think it is time that we look into the earlier phases of our evolution with an open mind and carefully examine the currently available fossil evidence rather than immediately dismissing the fossils that do not fit our long-held hypotheses,” said Haile-Selassie.

Because fossils are scarce and any trace of DNA is long gone from specimens this old, there are many important questions that will be difficult to answer. It certainly appears that multiple human ancestors or early hominids lived in the same region at roughly the same time, they may not all be actual genetic ancestors. It is also unclear how these species interacted or shared the resources of the region.