Professor Tim Lenton of the University of Exeter and Professor Simon Poulton of the University of Leeds have proposed that sponges produced the original oxygenation of the Earth in an article published in the March 9, 2014, issue of the journal Nature Geoscience.
The concept that the first multicellular animals that appeared on Earth between a billion years ago and 542 million years ago caused the increase in oxygen levels in the oceans and atmosphere that was necessary to sustain large animal life is diametrically opposed to present theory.
The researchers pin their theory on recent work by Dr. Daniel Mills at the Nordic Center for Earth Evolution at the University of Southern Denmark and Lewis M. Ward from the California Institute of Technology that proves sponges do not need high levels of oxygen to survive and the anatomy of sponges.
Sponges natural feeding mechanisms resulted in an increase in oxygen in the deeper parts of the ocean by the removal of phosphorous and the amount of plant matter that naturally falls to the ocean floor.
More oxygen in the deeper ocean provided the potential for the development of life that eventually moved to land.
The entire set of events took over 1.5 billion years.