Dang. Who knew weblogging could be so competitive? I just sat down to write a few things about the new Homo erectus specimen, and discover that Carl Zimmer beat me to it. That's OK, though, he's done the usual superb job of pointing out one of the interesting things about this new fossil: it highlights the wide range of forms we find in Homo erectus. KNM-OL 45500, the new specimen, was a tiny fellow, and relatively recent, less than a million years old. What we see in the fossil record is a great cloud of variability in ancient human populations, and our problem isn't a dearth of specimens, or discrete morphologies that make transitions invisible, but the richness of the record that makes it difficult to fit into simple models.

But hey, read Zimmer for the analysis, and I'll just use my bandwidth to show off the pictures. Here's the new specimen:

Partial hominin cranium, KNM-OL 45500, from Olorgesailie. Scale bars equal 1 cm. (A) Frontal bone, anterior view (left) and right lateral view (right). The squama is broken roughly 10 mm anterior to the bregma and along most of the coronal suture. The lateral portion of the left supraorbital region, near the anterior root of the temporal line, and two fragments from the left side of the frontal squama are missing. A lateral segment of the coronal suture, 18 mm long, is poorly preserved on the left side to the approximate position of the pterion. (B) Left temporal bone, lateral view (left) and inferior view (right). The petrous portion is missing, broken at its base from the temporal. Two small fragments of the lateral portion of the tympanic adhere to the bone as part of the medioposterior wall of the mandibular fossa and the posterior wall of the external acoustic meatus. A slender fragment (27 x 7mm) of the greater wing of the sphenoid bone is articulated to the lower half of the temporal's anterior suture.

There's also an accompanying summary by Schwartz that included this fascinating picture of a series of erectus specimens:

Various specimens attributed to Homo erectus. The Trinil fossils (the H. erectus type specimen) and the Sangiran fossils represent the same species and show a wide range of individual variation. Note the odd shape of Trinil and Sangiran rear profiles, variation between individuals, and differences between these specimens and various specimens from Africa and Eurasia (G-L). (A and B) Trinil skull cap (front and rear views). (C) Sangiran 2 (rear view). (D) Sangiran 12 (rear view). (E) Sangiran 4 (internal view of right petrosal bone, rear toward right; note number of grooves behind and across the bone, rather than a single, well-defined sigmoid sinus coursing behind). (F) Sangiran 4 (rear view). (G) Dmanisi D2282 (rear view). (H) Dmanisi D2280. (I and J) OH 9 (front and rear views). (K) Ceprano (three-quarter view). (L) KNM-WT 15000 (three-quarter view). Images not to scale.

I'll also mention that back in January, I cited a Natural History article that had a beautiful reconstruction of Homo erectus that I'll show again here:

Boaz T, Ciochon RL (2004) Headstrong Hominids. Natural History 113(1):29-34.

Potts R, Behrensmeyer AK, Deino A, Ditchfield P, Clark J (2004) Small Mid-Pleistocene Hominin Associated with East African Acheulean Technology. Science 305(5680):75-78.

Schwartz JH (2004) Getting to Know Homo erectus. Science 305(5680):53-54.