Vanishing acts have played a role in magic spectacles for centuries. But what might be good entertainment in a theatre is no laughing matter for paleoanthropology.
The human fossil record has recently experienced a possible disappearance of sorts. An increasing number of researchers now argue that Homo heidelbergensis, a key transition in human evolutionary scenarios, never existed. If true, this vanishing act could have horrifying consequences for naturalistic models.
Since the 1970s, paleoanthropologists believed H. heidelbergensis represents a transitional intermediate linking H. erectus to modern humans and Neanderthals. Some anthropologists believed that the “Heidelberg Man” is the common ancestor who gave rise to two separate lineages, one leading to modern humans and the other to Neanderthals and the Denisovans. Others thought that H. heidelbergensis solely led to Neanderthals and the Denisovans, while H. antecessor served as the common ancestor to the modern human and Neanderthal/Denisovan branches of the human evolutionary tree.
Researchers estimated that H. heidelbergensis existed between 800,000 and 200,000 years ago and made its home in Africa, Europe, and Asia. Support for this important hominid came from the discovery of 28 individuals recovered from the famous Sima de los Huesos (“the Pit of Bones”) in Spain. These hominids were dated to 430,000 years in age and assigned to H. heidelbergensis.
However, a recent reevaluation of this finding concluded that these creatures were much more Neanderthal-like than previously thought.1 On the basis of this conclusion, the research team from Spain argues that the Sima de los Huesos specimens couldn’t be H. heidelbergensis. This has led a number of anthropologists to argue that maybe H. heidelbergensis never existed at all.2
It is shocking to think that the re-analysis of fossil specimens from a single site can call into question the existence of one of the key transitional intermediates in most human evolutionary scenarios. If H. heidelbergensis disappears, it will leave evolutionary scenarios in a state of chaos.