Final answer:
H. floresiensis had a small brain size compared to other Homo species, with a cranial capacity of just 380 cc, but displayed complex behaviors similar to larger-brained relatives. This challenges the notion that brain size directly correlates with intelligence. Island dwarfism is a key theory explaining the smaller size of H. floresiensis, suggesting unique evolutionary pressures on islands.
Step-by-step explanation:
The brain size of H. floresiensis, often called the Hobbit due to its small stature, is quite small in comparison to other members of the genus Homo. With a cranial capacity of approximately 380 cc, akin to the size of an orange, H. floresiensis possessed a brain size that was significantly smaller than that of its relatives such as H. habilis and H. erectus, which had brain sizes of around 600-1200 cc.
Nonetheless, H. floresiensis exhibits complexities in behavior, such as making tools, using fire, and hunting, that are surprising given its small brain size. Moreover, the species exhibits evidence of 'neurological reorganization' that allowed it to maintain complex cognitive functions despite its reduced cranial capacity. This suggests that brain size is not the sole determinant of cognitive abilities. The phenomenon of island dwarfism is considered a leading explanation for the small stature and brain size of H. floresiensis, which supports the notion that environmental pressures on islands can influence the evolution of species in unique ways.