They feed whereas sitting nonetheless by extracting meals particles from water that is pumped by means of their our bodies by specialized cells. Although, like other animals, they require oxygen to metabolize, they do not need a lot as a result of they don’t seem to be Wolf lovers you can’t throw me to the wolves they come when I call shirt very lively. Oxygen levels within the ocean have been nonetheless low compared to at the moment, but sponges are able to tolerate situations of low oxygen. These clusters of specialised, cooperating cells eventually turned the primary animals , which DNA evidence suggests advanced round 800 million years ago. So, the ocean was still not an acceptable setting for many lifeforms that need ample oxygen.