The recent unearthing of a fascinating and well-preserved adult male skull, identified as MRD-VP-1/1 or commonly known as MRD, in Ethiopia has provided new insights into human evolution. This skull is considered the face of the oldest species so far discovered that is part of the human evolutionary tree. Dated back to the period when our ancestors were transitioning from tree-living to bipedalism, it offers critical data on a crucial stage in human evolution.
The Oldest of Australopithecus Group
MRD belongs to the Australopithecus group, which are early human ancestors who lived between 1.5 and 4 million years ago. These beings present an intriguing amalgam of ape-like and human characteristics with their protruding faces, potent jaws, and small brains, delineating a phase in evolution where humans were gradually stepping away from their primate lineage.
It was a time when our ancestors were still diminutive compared to modern humans and were capable of moving both on ground and amongst trees. Significantly, this species is regarded as the direct predecessor of Australopithecus afarensis, further exemplified by the famous partial skeleton – Lucy.
Lucy and Her Predecessor
Discovered in 1974, the 3.2-million-year-old Lucy belonged to Australopithecus afarensis, a species of hominins including humans and their ancestors. The recently studied MRD skull reveals that it belonged to the older species, Australopithecus anamensis.
Intriguingly, studies indicate that MRD’s species may have coexisted with Lucy’s species, an occurrence implied by a “speciation event”. It insinuates that a small group from MRD’s species could have become genetically isolated, evolving separately into Lucy’s species. Eventually, the population of Lucy’s species may have out-bred MRD’s species.
Between Our Earliest Ancestors and Lucy
This spectacular finding helps bridge a crucial gap between our earliest-known human ancestors dating nearly 6 million years back, and species resembling Lucy who lived around 2 to 3 million years ago.
| Evolutionary Milestones | Approximate Timeline |
|---|---|
| The split from chimpanzee lineage | 6-7 million years ago |
| Australopithecus Group period | 1.5-4 million years ago |
| Emergence of Lucy’s species | 2-3 million years ago |
| Appearance of Homo sapiens | 300,000 years ago |
Timeline of Human Evolution
The lineage leading to modern humans branched off from the chimpanzee lineage roughly 6-7 million years ago. During this period, a series of progressive evolutions resulted in critical traits such as bipedal walking, flatter faces, and larger brain size. These all culminated in the emergence of our species — Homo sapiens, which appeared around 300,000 years ago in Africa. The discovery of MRD thus provides vital evidence into this evolutionary journey, reinforcing our understanding of our own species’ origins and development.