Is your bath sponge a dead
Welcome to the venerable world of the demospongiae. These animals have been around for over five hundred million years. They have no true tissues, organs or nervous systems and they eat and breathe by letting the water flow through them (which is why they are full of holes). You've met them before of course, the familiar bath sponge is a member of this class of ancient animals.
Taken from this week's #CreteNature Blog: The Mind Blowing Dreamfish