Sponges (Phylum Porifera) are the oldest metazoan group still existing on Earth. Apart from the commercially bath sponges well known since the Greek civilization, more than 7,000 species are currently described and new ones are regularly discovered. They have remarkably survived over Earth’s changing chemical history since the Late Cambrian (509 MYA) in all aquatic environment, from marine intertidal zones to abyssal ones as well as in freshwater.
In the 19th century, Robert Grant coined the term ‘Porifera’ for sponges that were then recognized as an independent metazoan lineage. Increasingly, sponges are studied as part of a broader enterprise attempting to detail the Tree of Life.
Sponge research has brought practical answers to fundamental biological questions such as understanding the biosynthesis of chemicals and minerals, the evolution of eukaryotic immunology, understanding physiological adaptive strategies to cope with extreme environments or even revealing the functional and phylogenetic complexity of the ‘‘microbial universe’’ associated to sponge tissues. Many of these contemporary studies were based on international multidisciplinary efforts. Brazilian sponges have gained much scientific interest in the last decades due to the large diversity of these aquatic animal species.
The Brazilian school of sponge scientists began 20 years ago in cooperation with France. Today, Rio’s natural history museum stores a collection of more than 15.000 specimens collected around South America. There are several “sponge labs” now in Brazil, including Rio, Salvador de Bahia, and Recife where young scientists regularly embark into varied research areas mainly based on taxonomy.
Many books and illustrated field guides have come out recently, including the Catalogue of Brazilian Porifera. Due to their anti-infective, anti-cancer and anti-inflammatory properties, sponges have also received growing attention from pharmaceutical companies for the development of new natural products.
Sponges grow in distinct shapes and colors. More types can be found in tropical regions, less in colder parts of the world oceans. Sponges are divided into four distinct classes, 25 orders, 128 families and 680 genera. There are several hundred fresh water species.
Based on fieldwork in Chile, Argentina, Peru and Brazil, Dr. Willenz, researcher at the Royal Belgian Institute of Natural Sciences, in Brussels, is part of an international team coordinated by Professor Eduardo Hajdu (Museu Nacional, Universidade Federal do Rio de Janeiro) that is pursuing an ambitious goal to inventory South American sponges. Here is an exclusive selection of underwater images of sponges to be found off the coast of Brazil.