Grasping abilities among anurans: evolutionary perspectives based on anatomy and function.

MANZANO, ADRIANA S.

Punta del Este, Uruguay

Simposio; Symposium on Grasping hand. ICVM 9; 2010

International Society of Vertebrate Morphology

Frogs are characterized by a specialized morphology including a shortened trunk and tail, elongated ilia, and hind limbs, all traits thought to be associated with their saltatory mode of life. Despite this common body plan, diverse life styles have evolved among frogs including specialist aquatic, fossorial and arboreal species characterized by unique modes of locomotion. In contrast to the hindlimbs, the forelimbs are generally considered to be conserved among frogs. One major exception are arboreal frogs that often have relatively long forelimbs, capable of considerable dexterity during feeding. Phyllomedusines frogs show capacities to even perform a precision grip, hand ability supposed to be present only within humans. Grasping is one of the most remarkable abilities that can be achieved with a tetrapod hand. This ability has been repetitively linked to the evolution of the human lineage in its way to the development of technology, and was also explained as deeply related with the arboreal behavior of ancestral primates. Hand movements in humans and primates involve a remarkably complexity in the nervous pattern and function of delimited areas in the fore and hind brain. Similar movements of the digits and hands in arboreal frogs drive us to research on the anatomy of its nervous system. Some interesting differences between the anatomy and size  of the frog brain were related to different kind of live, such as a big size of the cerebellum in arboreal frogs and a noticeable irrigation of the forebrain, plexus choroideus, and the spinal cord in phyllomedusines species.