The unexpected abilities of sponges
A study conducted by the BEEM team (Molecular Biology, Evolution, and Ecology) of the Mediterranean Institute of Biodiversity and Marine and Continental Ecology, in collaboration with IBDM (Marseille), ENS (Paris) and ISEM (Montpellier) has characterized the buds of Oscarella lobularis as a promising model for studying cell development and sponge evolution.
Researchers successfully induced the in vitro production of these buds and maintained them in culture. These structures are small fragments of the sponge that detach from the adult body and develop into fully independent individuals. The study revealed that they possess remarkable properties from the early stages of their development:
- Regeneration ability: When a bud is cut in half, each piece can regenerate into a fully functional new bud. Even when completely broken down into individual cells, they can migrate, reconnect, and self-organize into structured layers.
- Autonomous metabolism: They filter water, consume oxygen, and move slightly using tiny cilia.
- Complex cellular organization: Their structure resembles that of more evolved organisms, making them a relevant model for understanding the evolution of early animals.
Imaging at the heart of discovery
To observe these buds in detail, researchers used advanced electron and fluorescence microscopy techniques. These analyses were carried out at the PICsl (IBDM, Aix-Marseille University) platform, a member of France-BioImaging.
Thanks to these high-resolution images, scientists were able to examine the buds’ development, cellular organization, and internal functioning, revealing mechanisms still largely unknown in the animal kingdom.
Why study sponges?
If we trace back the phylogenetic tree of animals, it is possible that we share a common ancestor with this species! It may seem hard to believe, but we actually have similarities with sponges.
Sponges are among the oldest organisms on Earth. Studying them could help us understand the origins of animal ancestral features among which the formation of cell layers.
Read the full article: https://pmc.ncbi.nlm.nih.gov/articles/PMC11587685/
Marine Béraud • March 12, 2025