PeerJ Author 135 Points Contributions by role Author 135 Contributions by subject area Ecology Freshwater Biology Martijn C Bart PeerJ Author Summary Biological Oceanography Ecology Marine Biology Past or current institution affiliations University of Amsterdam PeerJ Contributions Articles 1 January 4, 2019 Spiculous skeleton formation in the freshwater sponge Ephydatia fluviatilis under hypergravity conditions Martijn C. Bart, Sebastiaan J. de Vet, Didier M. de Bakker, Brittany E. Alexander, Dick van Oevelen, E. Emiel van Loon, Jack J.W.A. van Loon, Jasper M. de Goeij https://doi.org/10.7717/peerj.6055 PubMed 30631642