Several years ago, a group of scientists from Germany’s Senckenberg Research Institute set out to give a human face to archaic hominid species that formerly roamed the Earth. They produced 27 model heads using advanced forensic techniques based on bone pieces, teeth, and skulls discovered across the world during the previous century. The painstakingly carved skulls are the result of years of archaeological work in Africa, Asia, and Europe.
At least a dozen human-like species have existed on Earth during the previous 8 million years. The face reconstructions, which are part of the Safari zum Urmenschen exhibition (“Safari of Early Humans”), take us on a trip through time, beginning seven million years ago with the species sahelanthropus tchadensis and ending with modern-day Homo sapiens. Each face offers a unique tale about the lifestyles of hominids throughout their distinct eras, including where they lived, what they ate, and how they died.
When the show opened, it sparked widespread controversy, owing largely to decades-long scientific disagreements about the categorization of these ancient species. Fossils are notoriously difficult to classify as one species or another. Only a few thousand fossils of pre-human species have been unearthed, and whole sub-species are sometimes only known from a single jaw or incomplete skull. Additionally, unlike contemporary humans, no two hominids were similar, and it is difficult to tell whether differences in skull traits indicate different species or variations within the same species. For instance, the recent discovery of a skull in Dmansi, Turkey, suggests that a number of extant species of early “Homo” – Homo habilis, Homo rudolfensis, Homo ergaster, and Homo erectus – are really variants of a single species.
Bones can only tell us so much, and specialists are obliged to make informed estimates to fill in the gaps in an 8 million-year-old hominid family tree. Paleoanthropologists are forced to rewrite the beginnings of humans I with each new finding, adding new branches and recording when species split, and many discoveries, rather than giving answers about our distant past, merely raise additional questions.