In this work was identifyed the diferents opening forms of the palm nuts Syagrus romanzoffiana by brazilian squirrel Sciurus ingrami in four diferents points of Curitiba, Paraná, Brazil. Was caracterized tive basic forms of opening, in acording with the number of incisions and opening aspects. The form with lower number of incisions (two) was also the greather frequently in the four points sampled (66,25%; N = 5194) well as registred the lower opening time (7,2 ± 1,7 min) in relationship with other forms (9,2 ± 2,3 min). To explicate the diferences in the frequences of forms discovered, is proposed "apprenticeship's hypothesis" which the young squirrels of the population, along the opening nuts apprenticeship, to passing of the forms with larger number of incisions to forms with lower number of incisions, ending in the form of more frequence, which is maintained by adult squirrels.
Rodentia; Sciuridae; seed predation; squirrel behavior; palm nuts