Sponges sneeze mucus to shed particulate waste from their seawater inlet pores.

Sponges, among the oldest extant multicellular organisms on Earth, play a key role in the cycling of nutrients in many aquatic ecosystems. They need to employ strategies to prevent clogging of their internal filter system by solid wastes, but self-cleaning mechanisms are largely unknown. It is commonly assumed that sponges remove solid waste with the outflowing water through distinct outflow openings (oscula).