New research reveals underwater sponges are a powerful and affordable collector of DNA from marine ecosystems

A new paper published today has found that sponges, which can filter 10,000 litres of water a day can be a very effective way to collect animal DNA from the ocean.

A growing interest in environmental DNA (eDNA) has led scientists to explore different methods of attaining samples, by sampling ocean water and filtering out cells to analyse data. However many of these methods are expensive and excessive amounts of time.

The study states that, ‘the natural sampler DNA’ (nsDNA) approach is poised to become a powerful, affordable, universal tool for aquatic biodiversity monitoring globally.’ The approach uses 1000-fold the sampling effort normally achieved through current rosette-based sampling in marine habitats.

The researchers obtained sponge samples from Mediterranean and Antarctic ocean surveys which found thousands of DNA samples from animals such as fish, seals and penguins. This study demonstrates that sponges can be used to monitor biodiversity underwater.

Research Leader at the Natural History Museum Dr Ana Riesgo says, 'Sponges are everywhere, even in freshwater ecosystems, they can live from intertidal waters to depths of 4,000 metres. That opens the possibility to sample deep sea communities and see what organisms live down there.'

Dr Riesgo and her colleagues were able to identify up 31 different species of vertebrates based on the eDNA trapped within samples of sponges collected in Antarctica and the Mediterranean. This means that by sampling sponges, scientists could potentially be able to build up detailed pictures of entire ecosystems.

Additionally, the authors found that the presence of sponge DNA did not interfere with their ability to identify the DNA of other species caught within its tissue. Instead, they found that by using a particular DNA primer, which is a short sequence of nucleic acid that probes the DNA of specific organisms, they could selectively amplify vertebrate DNA while avoiding amplifying the sponge’s DNA itself.

'The benefit of using sponges is that they are filter feeders, but there are other filter feeders in aquatic systems,' says Dr Riesgo. 'So perhaps combining several species, such as sponges, jellyfish and polychaetes, you could sample most of the organisms living in a community. There are still a lot things we need to test, but this is really exciting.'

The paper was published in Current Biology.

ENDS

Notes for editors

Media contact: Tel: +44 (0)20 7942 5654/ (0)779 969 0151 Email: press@nhm.ac.uk

The Natural History Museum

The Natural History Museum exists to inspire a love of the natural world and unlock answers to the big issues facing humanity and the planet. It is a world-leading science research centre, and through its unique collection and unrivalled expertise it is tackling issues such as food security, eradicating diseases and managing resource scarcity.

The Natural History Museum is the most visited natural history museum in Europe and the top science attraction in the UK; we welcome around five million visitors each year and our website receives over 850,000 unique visitors a month. People come from around the world to enjoy our galleries and events and engage both in-person and online with our science and educational activities through innovative programmes and citizen science projects.