Comments to Angulo et al. 2016 on "Sea-level fluctuations and coastal evolution in the state of Rio de Janeiro, southeastern - Brazil" by Castro et al. 2014.

Interpretation of sea-level indicators is essential when studying paleo sea-level fluctuations during the Holocene. Sea-level indicators may have different origins, such as geological (beachrocks) and biological (vermetids and barnacles). In order to reconstruct paleo sea-level, it is necessary to attribute an indicative meaning to each sea-level indicator.