Questioning the Flores dwarf Stegodon remains

Nicolas Rolland and Susan Crockford have a short piece in the current (June 2005) Antiquity concerning the Stegodon remains from Liang Bua (link courtesy of Jacques Cinq-Mars of the Palanth forum).

The article questions whether the Stegodon associated with the hobbits were really dwarfs:

Liang Bua Cave stands out for two remarkable findings: the first scientifically reported discovery of Pleistocene dwarf humans and a reported association of dwarf Stegodon remains, which establishes co-existence with humans (Morwood et al. 2004). The dwarf Stegodon remains (no species designated) are described, without fanfare, as an assemblage dominated by juvenile individuals. However, a Late Pleistocene dwarf Stegodon species from Flores is news indeed and calls for further clarification.
The present understanding of the succession of Stegodon species on Flores is that endemic dwarfs, represented by the Early Pleistocene species Stegodon sondaarii (from the Ola Bula Formation and Kopo Watu), became extinct by around 840 kyr (van den Bergh et al. 2001). These dwarf forms were then replaced by the medium to large-sized S. florensis, a species closely related to the S. trigonocephalus group found in Java and Wallacea islands. Thus, dwarf stegodonts became extinct before the proposed early Mid-Pleistocene peopling of Flores (Morwood 1998) and the species to co-exist with any human population on Flores should have been the normal sized Stegodon florensis. Therefore, the report that a dwarf species of Stegodon co-existed with Mid-Pleistocene hominids on Flores well after the extinction of S. sondarii is either low-key reporting at its most extreme or an error.

Rolland and Crockford "wonder" whether there actually is any evidence for dwarf size in the preserved remains, whether they may have dated to times prior to the human occupation of the cave, or their assignment as dwarfs was purely erroneous.

Remember that the initial interpretation of endemic dwarfism for the human population of Flores was argued to be credible because of the existence of other dwarf mammals, principally Stegodon. But Flores is much larger than many other islands where dwarf megafauna have been found, and the main size changes in other taxa are those of the large rodents and the Komodo dragons, who are themselves probably not phylogenetic giants.

In other words, Flores is looking less and less like the land that time forgot. Hopefully further documentation of the Stegodon remains will resolve this part of the puzzle.