Know Your Hominin: A. L. 822-1

A. L. 822-1 was discovered in 2000 at Hadar, Ethipia. It is attributed to Australopithecus afarensis and is, at the time of discovery, the only complete skull of a female A. afarensis. The skull dates to approximately 3.1 MYA and is one of three that preserves both a cranium and a mandible (the others being A.L. 444-2 and A.L. 417-1).

Literature

Kimbel and Rak (2010) The cranial base of Australopithecus afarensis: new insights from the female skull. Phil. Trans. R. Soc. B 2010 365, 3365-3376, doi: 10.1098/rstb.2010.0070

Kimbel (2009) Australopithecus afarensis and the Mosaic Evolution of the Hominin Cranial Base. Note: This is an audio presentation given at a seminar hosted by the Royal Society in 2009.

Changing Views on Australopithecus afarensis

The other day I stumbled across an interesting article by Kimbel and Delezene, published last year in the Yearbook of Physical Anthropology, called ‘‘Lucy’’ Redux: A Review of Research on Australopithecus afarensis. I’m just now getting around to reading it and one paragraph jumped out at me:

Some Random Thoughts About Australopithecus sediba

I am going to be very busy today so I won’t get an in depth post up on Australopithecus sediba until tomorrow. In the meantime three items jumped out at me so I thought I would, briefly, mention them.

Things You Would Like To See

Science Daily has an item concerning the Laetoli foot print study in PLoS One. One bit stands out:

The subjects walked both with normal, erect human gaits and then with crouched, chimpanzee-like gaits.

Film of the latter would be interesting – lord knows we were disappointed with last year’s Ardipithecus special on that score… Speaking of, why is the idea that some of our ancestors were bipedal on the ground but still spent a lot of time in the trees news?

And then there is this (also from Science Daily):

This morphology differs distinctly from our own genus, Homo, who abandoned arboreal life around 2 million years ago and irrevocably committed to human-like bipedalism.

I guess Homo habilis don’t count, eh? I hope the PLoS One article is better (I haven’t read it yet).

The Diet of Australopithecus afarensis

PhysOrg.Com has an interesting item on research presented to the Royal Society on October 20th. The research concerns microwear analysis on australopithecine teeth. The research specifically focuses on Australopithecus afarensis (woohoo, take that Ardipithecus)

Interesting Fossil Pictures: Australopithecus afarensis

AL 288-1 casts a large shadow. The fact that such a large percentage of Lucy’s skeleton was recovered has overshadowed – at least in the public’s mind – that fact that a wide variety of fossil material was recovered at Hadar.

Rak and Australopithecus afarensis: A Second Look

Back in April of 2007 I wrote a brief post on a paper by Rak, Ginzberg, and Geffin. I had meant to write a more in depth post about it but kept procrastinating.

Is Australopithecus afarensis Too Derived to be a Human Ancestor

My reaction on first hearing about this paper.
Having gotten that out of the way, I sat down and read the paper – which was published in PNAS. The paper was written by Yoel Rak, Avishag Ginzburg, and Eli Geffen. The short version is that Australopithecus afarensis displays mandibular traits that indicate it is too derived to be a human ancestor. The longer version is a little bit more interesting, although I am inclined to be somewhat skeptical.

Australopithecus afarensis and Apes: One from the Archives

I’m currently trying to get through a rather lengthy book – which I will be reviewing in a later post – so in the meantime here is one from the archives… I wrote it back in April of 2005 and think I would write it somewhat differently today. I’ve toyed with doing a similar post on the post-crania …
One of the most aggravating things one can hear, if one has any training in paleoanthropology, is that the australopithicines were nothing but glorified apes. So let’s study the issue (hey, I have to justify the name of this blog, okay! Which means more hominids.) The first set of pictures below is a frontal view of A. afarensis, a chimp, an orang and a gorilla.

The Juvenile Australopithecus afarensis

Back in August, 2005, I wrote a post on Dinosaur Embryos, Growth and Human Evolution. One section of the post discussed attempts to study the growth patterns of KNM-WT 1500, in particular, and Homo erectus in general. I followed the discussion with:

More intriguing is the possibility that this type of analysis could be extended to earlier fossils. Interesting fossils have been found in Drimolen, South Africa (about five years ago). The finds consisted of the bones of two infants. One was 2-3 years of age, the other 8-10 months. One is tentatively assigned to the genus Homo, the other to Australopithecus robustus (the interesting thing about the A. robustus infant was that a lot of the robustus traits were clearly visible on the fragments – indicating that even early in life their are species differences among the australopithecines). Although the finds were fragmentary and only few bits of the crania were found one wonders if in a few years the above type of analysis could be extended to these fossils as well.