7 reasons why sea sponges are the coolest

Posted by Emily Buchanan — 16 June 2017 at 4:44pm - Comments

Sea sponges. They’re not exactly the cuddliest of creatures. They don’t have eyes, limbs, ears, a mouth or even a brain. They can’t move and some of them look a bit like Wotsits.

Often branded ‘humble’ or ‘primitive’, most people think sea sponges are just funky plants that live in coral reefs and are used as trampolines by baby fish. But in actual fact, they’re the world’s simplest multicellular animals. And I’m here to tell you that they’re the coolest, too, for seven compelling reasons.

They were the first animals on earth

New research suggests that sea sponges have been around for 640 million years. That’s 400 million years before the dinosaurs and 100 million years before anything else! In that time they’ve lived through a lot, including mass extinction, and scientists think they’ll probably survive climate change, too.

Some of them are humongous

There’s a sea sponge in Hawaii the size of a minivan. That’s 12ft wide and 7ft long. Marine biologists think it’s around 2,000 years old - making it the oldest living animal on earth. The mammoth creature was discovered 2,100m deep using a submersible, the kind that Greenpeace used in January to capture the first ever pictures of the mysterious Amazon Reef.

They’re still baffling scientists 

Talking of the Amazon Reef, sea sponges are thriving there, too. Whilst we didn’t spot any van-sized sponges (not yet, at least), we did observe over 60 species of sea sponge – including one that bears an uncanny resemblance to SpongeBob SquarePants. These sponges form part of a coral reef that’s baffling the science community, growing in an area with no light, no photosynthesis and extremely small amounts of oxygen. Indeed, it’s being called ‘one of the most surprising finds in modern sea research.’

Yet the reef is under threat. Oil companies are preparing to drill for oil nearby, putting the reef at risk from an oil spill that would have devastating impacts on marine life. Read more about our campaign to save this pristine ecosystem.

They can regenerate

If you tear up a sea sponge into thousands of microscopic pieces (not that we condone that!), those pieces will clump together and regenerate, turning into loads of new sea sponges. Watching this process under a microscope is like looking 640 million years into the past, giving us a fascinating insight into how life on earth was first formed. This is perhaps why sea sponges are so resilient – they can literally rebuild themselves from a single cell up.

The crambe crambe chemical shield

It can be hard for some sea creatures to defend themselves, especially when they can’t move, but there’s a type of sea sponge that can deploy a chemical shield. The artfully named crambe crambe, or the encrusting sea sponge, spews out a giant ‘chemical halo’ to ward off would-be predators. It’s also very territorial so uses the toxic haze to stake out its turf and stop other species moving in next door.

Puffball power

The orange puffball may sound like a My Little Pony character but this sea sponge is teaching engineers a thing or two about architectural design. New research shows that the tiny structural rods in orange puffball sponges have evolved to avoid it being squished. The rods, aptly named strongyloxea spicules, are thinner than a human hair and could provide a blueprint for increasing the resistance of human-made structures, like buildings and bike spokes. 

The sponge loop of sustenance

Something that’s perplexed scientists for decades is how coral reefs can thrive in water with little to no nutrition. But researchers from the Netherlands say it’s all down to the noble sea sponge. 

To eat, sea sponges filter thousands of litres of water a day and during this process, they turn carbon and nitrogen into nourishment for larger organisms, like snails and crabs. This is known as the ‘sponge loop’ and scientists say that these findings could benefit efforts to save endangered coral reefs. So sea sponges are basically conservation superheroes.

An ode to sea sponges

Sea sponges. They’re older than time, some of them are humongous and they seem to possess superpowers, from protective shields to reincarnation. Their fascinatingly simple genetic makeup is helping scientists to decode the history of life on earth and the more we know about them, the more we realise how fundamental they are to a healthy, thriving marine ecosystem. And that’s exactly why we need to protect them. 

You can help to defend these amazing creatures by signing the petition to stop risky oil drilling near the Amazon Reef.

About Emily Buchanan

Creative producer at Greenpeace UK.

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