2Department of Marine Biology and Limnology, Panama University, Panama City, Panama the absence of these two groups in the shell middens of Isla de Las Perlas, it was concluded that they were used exclusively for bartering [6].
1Department of Natural, Exact and Technology, Panama University, Panama City, Panama 2Department of Marine Biology and Limnology, Panama University, Panama City, Panama the absence of these two groups in the shell middens of Isla de Las Perlas, it was concluded that they were used exclusively for bartering [6].