Sponges aren't just something that you use to clean a plate. They're also animals. Have a look...
The sea sponge is a multicellular organism that lives in the ocean. They live attached to rocks in all types of water, from tropical reefs to arctic regions. But whatever climate they live in, they prefer calm waters. Why? Because they feed and breathe by allowing water to pass through the many holes, or pores, in their bodies. (Too much dirt and sand kicked up in the water would clog the holes and suffocate the sea sponge.)
So, why are we so excited about sea sponges? They don't move around or do anything. True. But they are an important part of marine ecosystems. As they feed and breathe, they also filter and clean the water around them. This benefits all animals and plants nearby.
And under the right conditions, they can also live a long time. And grow quite large, too. One such sea sponge was recently discovered by the Okeanos Explorer. (You might remember the Okeanos from our recent article on a glowing jelly.) The sponge was about 3.5 metres long, 2 metres tall, and 1.5 metres wide (12 x 7 x 5 feet). That's about as big as a minivan, or a large hippo. It's the largest sea sponge ever recorded.
But here's the real jawdropper. Scientists on the expedition estimate that, based on its size, it could be well over 1,000 years old. (This is because it would take at least that long for it to grow to that size.) Neat, huh? So for all of those people looking for the secret to long life, turns out all you need to do is live 2,000 metres (7,000 feet) deep off the coast of Hawaii. And be a sea sponge.