By Casey Frye, CCNN Writer
SpongeBob SquarePants may be a lovable character full of life and enthusiasm, but in the real world, sea sponges are kind of boring. They don’t have noses, eyes, ears, fins, or even brains. Well, they may look pretty lifeless, but researchers believe they’re the main reason complex animals like humans are alive today.
Way back in the day, about 700 million years ago, the ocean was filled with a bunch of dead microbes (tiny organisms). As they rotted, they used up the little oxygen that was in the water and left the ocean deprived of this critical element. That made the ocean unsuitable for life to really take off and become more complex. Fortunately, hungry sponges saved the day!
In order to eat, sponges filter water through hundreds of pores located throughout their body. When they do, they filter out all those oxygen-sucking microbes from the water. So, as sponges squeezed out the little buggers millions and millions of years ago, the ocean became enriched with oxygen to the point that more complex life forms could evolve. You know, like fang-filled predators that could actually hunt down prey. Then, those animals became more and more complex as they evolved to inhabit dry land.