According to Yahoo News a new study is being published in Biology Letters that performs a meta analysis of all studies of primates in relation to island dwarfing:
Lindell Bromham and Marcel Cardillo trawled through published journals and online databases to see how primates performed when subjected to the “island rule.”
True enough, small primate species (ones weighing less than five kilos, 11 pounds) all pumped up compared to their mainland relatives — but all the larger primates became smaller, in a range of between 52 and 80 percent.
That fits in well with H. floresiensis, who was around 55 percent of the mass of a modern Indonesian and probably 52 percent of an H. erectus.
So the evidence backs the idea that the hobbits were an insular dwarf race — humans who became smaller, possibly after the island separated from the mainland and left them marooned with diminished food resources.
The authors refuse, though, to wade into the debate as to whether the hobbits were H. erectus or H. sapiens.
Also unclear is why the hominids had a relatively undersized brain compared to their diminutive body. A modern human child of the same size has a much larger brain, as do pygmies.
About time for that kind of study…
The study is available here, if somebody could send me a copy (it is secured access) I would appreciate it.
Update 1: Tim Jones has some thoughts on the subject and Hawks discusses the island rule among carnivores.