Were I to show you the skeleton of an adult humanoid creature, standing about 40 inches in height, and with the brain capacity of a chimpanzee, you might immediately think of “Lucy”, a member of the hominid family, Australopithecus, which lived some three million years ago. Were I to tell you that these remains are in fact dated to about 18,000 years ago and were recovered from a small Indonesian island called Flores, you might perhaps want to revise your guess. You would probably settle for a surviving descendant of homo erectus, who first emerged from Africa about two million years ago, and may have been a direct forebear of homo sapiens. Restricted to their small environment, their brain capacity may well have shrunk to half its original size, a phenomenon not unknown in isolated non-human populations. Alternatively, the lack of challenge in a very restricted and safe environment may not have provided the evolutionary need for the brain, and skull, to enlarge.

This would have been mystery enough. The discovery of homo floresiensis (to be swiftly nicknamed the “Hobbit”) in 2004 presented us with a creature who should have been extinct millions of years ago, but was in fact our contemporary throughout most of human history. Indeed, if local legends are true, it might have survived as late as the 16th century. While you could be right about homo erectus, for the theory has respectable champions, the latest information suggests otherwise.

The bones of the legs and the pelvis show Hobbit to be bipedal, a characteristic of the homo line. But the feet are disproportionately long and lack proper arches. These primitive traits suggest an awkward, high-stepping, gait. But the big toe is aligned and not splayed out as it would be in an Australopithecine. The trapezoid bone in the wrist is ape-like in shape, and so less suited to tool making and similar operations than the normal homo version.

The skull is simply a mixture. The brain it encased was about the size of a grapefruit, similar to a chimpanzee, yet it has the narrow nose, brow arches and small teeth which suggest the homo line. Interestingly, the brain would have had an enlarged area which is believed to be associated with complex cognitive skills. This might explain the Hobbit’s ability to manufacture relatively sophisticated stone tools for hunting, and indeed may have influenced our homo sapiens ancestors in this regard. And they also used fire for cooking.

So a theory is gaining ground that the Hobbit is a newly discovered branch on the homo line which emerged before, and perhaps well before, homo erectus. Until this point the oldest hominid who moved out from Africa was thought to be homo erectus, and its remains, dating from about 1.8 million years ago, have been found in Georgia. But the Hobbit suggests the possibility that the first members of the human family spread out from Africa, perhaps hundreds of thousands of years before that, and survived until relatively modern times.

Tracing the hominid tree from the last ancestor we shared with the apes has always been a complex task. The separation took place about six mya (million years ago). The evidence is restricted to chance finds which have survived because conditions happened to have been conducive. And all too often these finds are no more than clues from which inferences have to be made. Nevertheless, broad patterns appear.

Perhaps the most telling of these is the increase in brain size. We first find this at an average of 450cc about 3.5 mya. By 2.5 mya (homo habilis) it has grown to 750cc, and at 2.5 mya, with the arrival of homo erectus, it has become 1000cc. At around 195,000 years ago, homo sapiens appears, with a brain capacity of 1330 cc.

There is a parallel pattern of apparent brain functionality. The first, and crude, stone tools appear at 2.5 mya, and the skill gradually develops to sophisticated blades and grinding stones about 100,000 years before homo sapiens (who will graduate to bronze tools about 95,000 years later, shortly before the first evidence of writing).

The use of fire, shared childcare, purpose-built shelters and cooking all appear before homo sapiens. And a report in December 2009 described the relics of sophisticated settlements (near the Dead Sea) dated to 750,000 years ago - half a million years earlier than we previously thought.

If we throw into the mix painted Neanderthal jewellery, made some 10,000 years before homo sapiens entered Europe, and take into account somewhat less secure evidence of burial practices, it becomes increasingly difficult to square the scientific evidence with the concept of the first ensouled hominids being members of our own species. By “ensouled” I mean with intelligence, a sense of right and wrong and a recognition of the sacred.

I am aware of the difficulty this causes with the concept of sin coming into the world through one man - which led to Pius XII to say: “Now it is in no way apparent how such an opinion can be reconciled with that which the sources of revealed truth and the documents of the Teaching Authority of the Church propose with regard to original sin, which proceeds from a sin actually committed by an individual…” I do not pretend to reconcile the scientific evidence with the theological. I rest in the confidence that, when both are properly understood, they will be reconcilable. But you may well have a solution to give us on www.secondsightblog.com. I may return to this question in a future column.

Postscript. My friend Edmund Adamus points out that the view of the Congregation for the Clergy, quoted in my last column, that the faithful had no business advising the hierarchy, was shortly to be reversed by the 1983 revision of Canon Law. So thank you to him for refining the point I was making.