Newly found early Homo species shakes up human evolution theory

The mystery of human evolution is nowhere close to being resolved. Every new discovery not only peels off the layer of truth but also brings forth a plethora of questions.

The recent fossil discovery of ancient teeth in Ethiopia suggests that the evolutionary past of humans is far more intricate than a simple linear progression.

The new research led by UNLV anthropologist Brian Villmoare in a partnership with Ledi-Geraru Research project, has unveiled that Australopithecus and Homo species coexisted between 2.6 and 2.8 million years ago in the same part of Africa.

The finding not only challenges the traditional ape-to-human evolution theory but also reshapes the human evolutionary tree.

According to researchers, “These specimens suggest that Australopithecus and Homo coexisted as two non-robust lineages in the Afar region before 2.5 million years ago and that the hominin fossil record is more diverse than previously known.”

Kaye Reed, a co-author of the study, said the discovery shifts our perception of human evolution.

“Here we have two hominin species that are together and human evolution is not linear, it is a bushy tree. There are life forms that go extinct. This new research shows the image many of us have in our minds of an ape to Neanderthal to modern human is not accurate. Evolution does not work like that,” Dr Reed explained.

Analysis of the fossilized teeth, published in the journal Nature, exhibits they belong to a new Home species rather than Australopithecus afarensis – represented by the famous “Lucy” specimen – which last appeared 2.95 million years ago.

The new finding shows the antiquity and multiplicity of human lineage.

Multiple human lineages

The study shed light on the branching pattern of human evolution. According to this study, prior to 2.5 million years ago, eastern Africa may have had four hominin lineages including, early Homo, Australopithecus garhi, the Ledi-Geraru Australopithecus, and others.

According to Villmoare, “We used to think of human evolution as fairly linear, with a steady march from an ape-like ancestors to modern Homo sapiens. Instead humans are branched out multiple times into different niches.”