It is home to a diverse range of invertebrates including colonial ascidians, sponges and corals. The use of vanabins and vanadium for oxygen transport in ascidians and tunicates is doubtful. Almost all ascidians are hermaphrodites and conspicuous mature ascidians are sessile. These flatworms feed exclusively on colonial ascidians. They include polychaete worms, pelecypods, anthozoans, echinoderms, sponges, ascidians, crustaceans. It sometimes also preys on gastropods, crabs, barnacles, ascidians, sea squirts and algae. This nudibranch feeds on hydroids and other marine organisms such as ascidians and sea anemones. Some ascidians that live on soft sediments are detritivores. Various ascidians are used as food. Colonial ascidians reproduce both asexually and sexually. The anteroposterior regionalization of the neural tube in ascidians is comparable to that in vertebrates. "N. kubaryana" uses the toxins in its prey ascidians to defend itself against predators. The German chemist Martin Henze first detected vanadium in ascidians (sea squirts) in 1911. Like all ascidians, these sessile animals are filter feeders. The organization of Hox genes is only known for "C. intestinalis" among ascidians.