Sponges may have paved the way for all life on Earth
Researchers have suggested that the sponge, just by its very existence, may have paved the way for the complex life forms' evolution, including our own species.
According to the researchers, sponges seem to have added oxygen to the deep ocean, which created an environment where more mobile, major oxygen-using animals could have evolved.
Lead author Tim Lenton of the University of Exeter argued that first animals' evolution may have played a key role in the widespread oxygenation of the deep oceans, asserting that this in turn may have led to the evolution of more complex, mobile animals.
DNA analysis has found that the earliest sponges most likely emerged at least 700 million years ago, when the oceans had little oxygen. Between 700 and 600 million years ago, the oceans became more oxygenated, meaning more enriched with oxygen. Fossils of animals dating to 650 million years ago have been found, Discovery News reported.
Then when the sponges feed their pores and channels allow nutrient-containing water to circulate through them.
As they feed, they filter out tiny particles of organic matter from the water. The particles millions of years ago may have also included dead microbial matter that rots and consumes oxygen as it does so.
The researchers said that sponges, therefore, helped to clean water of this material and without the rotting going on, the water may have experienced increased oxygen levels.
The study has been published in the journal Nature Geoscience.
(Posted on 10-03-2014)