The sea sponge is one of the world’s simplest multi-cellular living organisms. They have been present on Earth for around 500 million years. There are over 5,000 identified species – 200 of which can be found in fresh water.
The ancient Greeks referred to these bizarre creatures as “Zoofitan” – a unique category of marine species – literally meaning an organism that is “half plant, half animal”. For, even to this day, they are often mistaken as corals or plants; lacking the features we commonly associate with living animals, such as brains and hearts. Despite their seemingly uninteresting appearance, sponges are actually vital, dynamic, fascinating creatures.
Instead of a morphology we recognise from other members of the kingdom Animalia, the bodies of sponges are made up of two tough outer layers with a “jellylike” layer between them, called “mesohyl”. From this simple structure, sponges grow into myriad shapes, sizes, colours and textures. However, they all share some incredible characteristics…
You can find sea sponges on every healthy dive site you visit. From little tube and encrusting sponges, to massive barrels, these benthic organisms are ubiquitous! There is a colony of enormous sponges off the coast of Canada. These Aphrocallistes vastus live in shallow water, and have grown to around three-and-a-half metres long, and more than a metre tall!
Scientists exploring the deep sea in the Papahãnaumokuãkea marine park have found the largest sponge ever recorded. Quoted as being “about the size of a minivan”, the creature is more than two metres long and over three-and-a-half metres wide, and lives at around 2,100 metres. There is some speculation that this could be the oldest creature on the planet.
Best Places To Dive:
- Gorontalo, Sulawesi, Indonesia
- Raja Ampat, Indonesia
- Banda Sea, Maluku, Indonesia
- Cebu, Philippines
- Puerto Galera, Philippines
Check out Scuba Diver AustraliaAsia + Oceanplanet “Blue Green Edition” Issue 2/2017. The issue itself is dedicated to conservation and honours the winners of the Bluegreen360 Awards 2017, presented to those businesses and individuals committed to eco-friendly practices and marine conservation.