Homo naledi – an entirely new perspective on human evolution?
The term „Breaking News“ will by now be widely familiar even to the non-English-speaking news audience. With almost nerve wrecking frequency is this expression used whenever something – sometimes more, sometimes less- dramatic happens in the world. Barely a day passes without us hearing or reading about some „Breaking news” from somewhere.But „Breaking News“ is actually what we received today from the world of science: In the journal „eLife“ paleoanthropologists report on the discovery of fossil remnants of an unknown human species, which theyfound in a cave in South Africa in 2013 and have extensively studied since. Is the discovery of a new human species in itself a scientific „Breaking News“, so is what the scientists reported today a real sensation, which merits broad much broader public attention beyond the circles of scientific expertise. It is the biggest find of human fossils on the African continent, the „cradle of humanity“. It is unique in the fossil record of humans and so extensive that on one stroke the paleoanthropologists know more about this new human species than about any other representatives of the human lineage.
The researchers baptized the new species „Homo naledi“. His skull, teeth and skeleton are largely similar to those of the earliest representatives of the species „Homo“, such as „Homo habilis“ or „Homo erectus“, which lived about 2 million years ago, whereas his shoulders’ morphology is even closer to that of apes. In a few other respects, however, the researchers identified characteristics of modern man: The feet of Homo naledi are thus barely distinguishable from those of us humans. His hands probably enabled him to use tools, whereas his comparatively strongly curved finger made Homo naledi a very good climber. His brain again was closer to the size of Australopithecus species, or modern gorillas, and thus even smaller than that of Homo habilis. And his teeth are also similar to those of the earliest representatives of our species.
This exceptional combination of anatomical features, a mixture of archaic and modernly human, distinguishes Homo naledi from all human species known so far. But what ultimately qualifies the finding as sensational is that based on the discovery site and the large number of different individuals, including children and the elderly, the researchers have to assume that the dead were deliberately placed at this location. It is thus something of an early human mass grave. All other options than the deliberate disposal of the dead by the survivors the researchers claim to be able to exclude. But the burial of the deceased has so far believed to be a ritual limited to modern man, Homo sapiens, or may be, as evidenced by a few vague findings, the Neanderthals, but certainly not part of the behavior pattern of a human species that has more features of Homo habilis, the brain volume of Australopithecus, and which may have lived 2 million years ago.
The burying of the dead is a very complex behavior. It presupposes the capacity for empathy, a certain form of consciousness, and developed transcendent ideas. In other words, it requires respect for those who passed away, knowledge of one’s own mortality, and a belief in another life after death, and last but not least the cognitive separation from nature. These are all exclusivecharacteristics of the cognitive frame and metaphysical belief system of Homo sapiens. But this species is far away from Homo sapiens in evolutionary terms, what makes this discovery all the more exciting. The possibility that creatures with such small brains have such highly developed cognitive skills of abstraction appears so radical, that many researchers see themselves forced to draw this conclusion into doubt. Unfortunately, the paleoanthropologists do not know the age of their latest finding. If it is only 100,000 years old, we might have a parallel evolution of the Homo line in front of us. If however, the fossils are as old as Homo habilis, as the morphology of the bones suggests, the researchers may have discovered the very starting point of the human evolution.
Both possibilities are exciting enough to assign the attribute „breaking news“ or even „sensational news“ to this announcement. Readers of tomorrow’s newspapers are well advised to read its science section more carefully rather than to focus on the politics or economics part. We can only dream of what there remains to discover about the origins of our human existence after all.