The transition from dominantly bacterial oceans to more complex eukaryotic ecosystems was one of the most profound revolutions in our planet’s history. It must have profoundly changed the distribution of carbon and nutrients in the oceans, and dramatically increased the flux of energy in Earth’s ecosystems.
However, we remain oblivious about when this transition occurred.
I will present new data from the biomarker laboratory demonstrating that bacteria were the only significant primary producers in the oceans for most of the Proterozoic. Complex life rose surprisingly late. Biomarker molecules show that complex eukaryotic algae conquered the oceans in the hot interlude between the first and second Neoproterozoic Snowball Earth events, precisely between 659 and 645 million years ago.
I will explain why and how this ‘Rise of Algae’ was responsible for the emergence of our earliest animal ancestors.
As a bonus I will present the discovery of 1 billion years old bright-purple porphyrin molecules, the oldest preserved pigments on Earth, and what they tell us about early life.