ANU-led study solves mystery of how first animals appeared on Earth

These large and nutritious organisms at the base of the food web provided the burst of energy required for the evolution of complex ecosystems, where increasingly large and complex animals, including humans, could thrive on Earth. Research led by ANU has solved the mystery of how the first animals appeared on Earth, a pivotal moment for the planet without which humans would not exist. Lead researcher Associate Professor Jochen Brocks said the team found the answer in ancient sedimentary rocks from central Australia. "We crushed these rocks to powder and extracted molecules of ancient organisms from them," said Dr Brocks from the ANU Research School of Earth Sciences. "These molecules tell us that it really became interesting 650 million years ago. It was a revolution of ecosystems, it was the rise of algae."   Dr Brocks said the rise of algae triggered one of the most profound ecological revolutions in Earth's history, without which humans and other animals would not exist. "Before all of this happened, there was a dramatic event 50 million years earlier called Snowball Earth," he said.