Living With Dinosaurs: Prehistoric Animals That Are Still Alive Today
Sea Sponges
Although they look like plants, sea sponges are one of the world’s oldest animals. Research from 2018 dates a fossil back to 660 million years ago. That’s 100 million years before the Cambrian explosion when most modern animals evolved.
Reinhard Dirscherl/ullstein bild via Getty Images
Reinhard Dirscherl/ullstein bild via Getty Images
According to one hypothesis, sea sponges may have kickstarted the Cambrian explosion. Since they don’t need much oxygen to survive, they could survive the world’s primitive ocean climate. They add more oxygen to the water, which allows more animals to evolve.
