Can sambaquis (shell mounds) be used as records of the Holocene marine fish biodiversity?

The documented quality of the zooarchaeological remains found in sambaquis is an important issue for ecologists who increasingly consider this material as a possible record of historical biodiversity to extend the observation periods of their analyses. In this work ichthyological inventories based on zooarchaeological remains were used to test the hypothesis that they do not differ statistically from those constructed by sampling current ichthyological diversity. Ichthyological records of 68 sambaquis of the Brazilian southeast coast were systematised. Data analyses were done based on taxa richness, taxonomic distinctness and food guild composition approaches. All analyses failed to show significant differences between sambaqui and modern fish inventories. Such result was kept for all tested scales and for the different studied regions. The current results indicate that sambaquis contain records of past species composition and therefore of Holocene biodiversity. It is concluded that sambaqui zooarchaeological remains should not be neglected in ecological studies and represent a quality alternative to extend the temporal scale of these studies.