Have we found the first sign of animal life on Earth?

According to a study published in the journal ‘Nature’, fossils of ancient sponges found in rock samples may be the earliest sign of animal life. They look like the skeletons of modern sea sponges, and date back 890 million years. That’s about 350 million years older than Dickinsonia – the oldest undisputed fossils of any animal. The fossils were unearthed in a rugged mountainous terrain that was a prehistoric marine environment. Apparently, these simple creatures were thriving in underwater reefs many millions of years earlier than previously thought.

Move over Dickinsonia

The history of animals – and by extension ours – is now back in the spotlight. “We are animals,” geologist Prof. Elizabeth Turner of Laurentian University in Canada who conducted the research told ‘USA Today’. “And we have a big brain, and we’re capable of wondering about stuff, and we wonder how we came to be. What happened before, and what was it like? How did it begin? This is really digging into that. I’m shaking up the apple cart.”

“The earliest animals to emerge evolutionarily were probably sponge-like. This is not surprising given that sponges are the most basic type of animal both today and in the fossil record,” Prof. Turner explained in a ‘Reuters’ article. “The existence of a protracted back-history is not surprising, but the sheer duration of it – a few hundred million years – may be a little unexpected for some researchers.”

“I believe these are ancient sponges — only this type of organism has this type of network of organic filaments,” Joachim Reitner, a geobiologist and sponge expert at Germany’s University of Göttingen told the ‘Associated Press’.

Let the debate begin

Some within the scientific community are cautious about the findings. The reason is because of ancient Earth’s oxygen levels and the circumstances under which the sponges lived.