An investigation has uncovered that the source of a prehistoric group of sea creatures isn’t as far back in history as we first thought. Scientists from Durham University (UK), Yunnan University and Guizhou University (China) studied the fossils and discovered that the fossils, which were previously believed to be the oldest Bryozoans, are actually green algae!
Scientists used to think that Bryozoans, which are animals with tentacles living in underwater buildings like skyscrapers, were very old. But now it’s been determined that they first showed up around 480 million years ago during the Ordovician period. This means they didn’t live during the time of a huge explosion of evolution 40 million years prior.
Researchers found that the emergence of bryozoans happened much later than previously thought, which means that new and different animals didn’t only appear during the Cambrian period. Ancient fossils in China showed us bits of an animal called Protomelission gateshousei for the first time, which we now know is a bryozoan. The findings were published in a journal called Nature.
The scientists studying a special type of tissue found out that it belonged to the ‘green algal group’ called Dasycladales. Dr Martin Smith from Durham University explained that a long time ago all the animal species around us were made, and this period is called ‘Cambrian explosion’.
Evolution isn’t finished yet! After the Cambrian period, which happened half a billion years ago, Bryozoans evolved and showed us that life wasn’t stuck in one form. This means evolution still exists today and it isn’t done just making small changes to existing creatures – it is still capable of making new things too.
Professor Zhang Xiguang from Yunnan University said that previous fossils only showed the bones of these early living organisms. But with our new findings, we’re able to see what was inside these chambers.
The researchers noticed something strange. Instead of tentacles that a Bryozoan would normally have, they saw leaf-shaped flaps! That means these weren’t animals but seaweeds! This means that the oldest fossil Bryozoans don’t exist until much later in history, during the Ordovician period.
Also, this leads scientists to think that earlier oceans may have had more seaweeds than we originally thought, even though things didn’t all happen at once.
A new study called “Protomelission is an early dasyclad alga and not a Cambrian bryozoan” was written by Jie Yang, Tian Lan, Xi-guang Zhang and Martin R. Smith on the 8 March 2023 and published in Nature journal. It was funded by the National Natural Science Foundation of China. The study found that Protomelission is an earlier type of sea algae instead of a type of small aquatic animal from Cambrian period.
