Great fossil discoveries from the human evolutionary line might seem like a natural story for this blog, but they pose something of a problem. On the one hand, they are that welcome bit of rare, primary evidence concerning what happened. That makes them the biggest story of all. The pitching hand, however, is forced to admit that these fossils, especially the pre-Homo erectus ones, rarely contain any evidence one way or the other about language. That makes them (for this blog) no story at all.
Today’s issue of Nature carries a news story about the discovery of a three-million year old skeleton of a three-year-old (approximately) Australopithecus afarensis female child (news story here; abstract here; Washington Post story here). This fossil, called familiarly, Selam, belongs to the same species at the 150,000-years-older Lucy fossil. The fossil was discovered in the year 2000 and has been receiving close (confidential) attention ever since. A. afarensis is generally not thought to be a direct ancestor of modern humans.
The most notable detail from this blog’s perspective is the possibility of air sacs in the throat. Chimpanzees, bonobos, gorillas, and orang-utangs all have air sacs in their throat that (possibly) allow them to make loud, continuous vocalizations without having to stop and catch their breath. People do not have these sacs, or at least we have them only in the most tiny, vestigial form. We manage breathing and vocalizing in a completely different manner that allows long-winded speech. This speculation about air sacs is based on the discovery of an ape-like hyoid bone . No older hominin fossil, including the Lucy fossil, has shown this bone.
The discovery of an ape-like hyoid bone in an adult fossil would show that the creature’s human vocalization skills had a long way to go. That would hardly be a surprise in a three million year old fossil that was not even directly related to modern humans. Of course they had a long way to go. But if the bone is turning up in young children and not in adults, then we get the amazing possibility that as part of reaching maturity, A. afarensis was developing a more human-like vocalization system. (Even today in H. sapiens infants the speech organs undergo a serious restructuring.)
I toss that kind of thinking out because this is a blog and can be a bit more free with the speculation than a peer-reviewed journal or even a serious newspaper can be. Obviously it will be a long time, if ever, before such speculation could be supported. I just toss it out there for people to play with. (Play! Do NOT start building systems out of such a toy.) The take-away message: More to come!