Ocean Life Evolution Theory Reversed, First Animals Created Oxygen
New research suggests that early animals brought oxygen to the ocean. First animals are what created the evolution of ocean life according to researchers, which goes against what was previously thought to be true.
Led by scientists at the University of Exeter in England, the study shows a spin on the popular belief that ocean life evolved from the increase in oxygen levels in the oceans. The study says that the animals were responsible for oxygenating the waters.
“We argue that the evolution of first animals could have played a key role in the widespread oxygenation of the deep oceans,” said Professor Tim Lenton, one of the authors of the study. He added that they were not the passive animals that scientists once thought they were. Instead, the first animals played an important role in the evolution of ocean life and, ultimately, marine biology. This theory completely goes against what the tradition view of how ocean life evolved.
The study was published Saturday in the journal Nature Geoscience. The research stems from a previous study that took place in Denmark in 2012, in which scientists found the first animals, sponges, needed minimal amounts of oxygen to survive.
Dr. Daniel Mills at the Nordic Center for Earth Evolution was involved with the study at the University of Southern Denmark. He co-authored the study, which was published in the journal PNAS. He explained that the first life forms on earth were single form cells, which needed very little oxygen to live. Lab testes of the sponges showed that they could live even when oxygen levels were reduced to 0.5 percent. This piece of information led the scientists to believe that if it was not lack of oxygen that prevented them from evolving, something else did.
Both studies run on the premise that the first animals existed in the ocean roughly 600 million years ago. They looked at species from the Neoproterozoic Era, studying oxygen levels of the ocean and determining how much of it was needed for early animals.
The feeding cycle of sponges, in which they intake water and deposit organic material, increased the oxygen levels in the water, making it possible for other species to survive. The food chain within the ocean all began with the oxygen generating sponge. These first animals are what ultimately led to the world largest ocean predators that are known today.
Co-author of the study, from the University of Leeds, Professor Simon Poulton, states that their research offers a valid explanation as to how ocean life evolved. Despite challenging the long-standing belief of how the ocean was oxygenated in order to support first animals in the water, he said that their research is worth taking a better look at oxygen levels from the Neoproterozoic Era.
Both of these studies challenge the traditionally held belief about ocean life evolution. They show that the theory is reversed and that, in fact, first animals are the cause of the rise in oxygen. Early animals were responsible for the evolution of the ocean life animals that exist today.
By Tracy Rose