When you imagine a Neanderthal you probably think of the classic image of the "cave man": heavy brow, monkey-like face, stooping posture, shaggy hair, holding a big club. Although this is not how most scientists imagine Neanderthals today (have a look at http://www.nhm.ac.uk/discover/who-were-the-neanderthals.html), the early images were based on observed characteristics of Neanderthal skeletal remains.
An Irish-based scientist, the geologist William King, had an important role in interpreting these remains and even provided the name Homo neanderthalensis to express his belief that they were the remains of a new species of hominid similar to, but distinct from, modern humans.
The position of Neanderthals in the ancestral tree of Homo sapiens has been a subject of debate since the first skull was discovered in Germany in 1856. Since then, fragments of more than 500 individuals have been discovered. Scientists have asked questions about Neanderthal language and cognition, about Neanderthal tools, about Neanderthal burial practices and beliefs.
Perhaps the most furious debate has concerned their relationship to fully modern humans. After the Neanderthal genome was sequenced in 2010, the debate has focused on how much interbreeding occurred between communities of Neanderthals and of Homo sapiens in Europe. In short, what percentage of our DNA did we get from Neanderthals?
Before genome sequencing, scientists could only use their knowledge of comparative anatomy to determine the relationship between fossilised remains and living organisms. Using a cast of a skull cap and the descriptions of other Neanderthal skeletal remains written by other scientists, King asserted that the remains found in the Neander valley were different enough from modern humans to form a new species.
King, originally from Sunderland, had been appointed a professor of geology at one of the newly opened Queen's Colleges in 1849. The controversial "non-denominational" colleges were the precursors of NUI Galway, University College Cork and Queen's University Belfast and aimed to increase the opportunities for Ireland's middle classes to access higher education. The colleges were particularly forward thinking in their focus on scientific instruction.
Isolated in Galway with few students but with a good laboratory and access to the ever-increasing scientific periodical press, King ranged widely across many sciences we might now consider separate. Most geologists today would think twice about debating the comparative anatomy of modern humans, chimpanzees and ancient remains. Yet when King obtained a cast of the unusual German skull cap, he compared it with a variety of other skulls (using both a collection of objects and descriptions in scientific papers) and concluded that the skull was so different from modern humans as to constitute a new species.
Before King’s contribution, the predominant view was that the Neanderthal might be a deformed or diseased human. King dismissed this idea with the suggestion that even the most degraded and “inferior” human races (as King believed races other than Europeans to be) showed a more spherical skull and a higher forehead than the Neanderthal skull cap suggested.
During the 19th century, a high forehead was believed to indicate superior intelligence. Australian Aborigines were most Europeans’ favourite example of a supposedly “degraded” and “savage” race and King believed that even their skulls showed more similarity to modern humans than the Neanderthal skull. In short, the Neanderthal skull’s “strong simial tendencies” led King to believe that it was simply too different from humans to be of the same species.
In his 1864 paper for the Quarterly Journal of Science he even proposed in a foonote that "I now feel strongly inclined to believe that it is not only specifically but generically distinct from Man". That is, not a member of the genus Homo.
It is hard for us to recapture the shock value of King’s ideas in asserting the existence of another species of human-like creatures at a time when the Biblical version of creation was widely considered an accurate description of the Earth’s history.
Things have come almost full circle from King's time: we now know that Neanderthals are our closest ancestor and probably interbred with humans. Yet what has remained curiously consistent is our belief that Neanderthals were inferior to modern humans, although the explanations have changed. Rather than the absence of a high forehead, scientists now refer to the absence of some kind of genetic adaptation that enabled Homo sapiens to create more advanced societies and out-compete their shorter, stockier neighbours.
Dr Juliana Adelman lectures in history at Dublin City University