14 DAY TRIAL // In a study focused on prehistoric seas that existed on Earth during the Pre-Cambrian Era, some 580 million years ago, researchers coordinated by NASA provide more data on how and why the earliest multicellular organisms evolved into larger, more complex organisms over millions of years.
The reason why the first organisms evolved into much more than they used to be has been a topic of debate in the scientific community. The mechanisms used for this process have been challenged by religious individuals to promote ideas such as creationism or intelligent design.
The new work therefore has the potential to put many of these debates to rest. Understanding how this evolution occurred is impossible without studying the environments that existed in the deep ocean so many millions of years ago. For this purpose, the research group has developed a complex simulation of how Pre-Cambrian seas may have looked like.
The investigation was led by scientists at the University of Toronto Mississauga (UTM) and the Massachusetts Institute of Technology (MIT) Node of NASA Astrobiology Institute. The group included Marc Laflamme, who is an assistant professor with the Department of Chemical and Physical Sciences at UTM.
Laflamme argues that increasing their size made sense for multicellular organisms at the time, given that they were living in dense communities at great depths, and competed for nutrients in a very hostile environment. The latter was reconstructed using a technique called canopy flow modeling.
The study revealed that organisms called Ediacara biota grew in size for a very simple and logic reason, which was to access the vast amount of nutrients flowing above the ocean floor, something that its competitors could not do.
Ediacara is now believed to be one of the earliest and most primitive examples of a large life form on the planet. Scientists estimate that the organism grew up to a meter (3.3 feet) in height above the ocean floor. Tapping the nutrient flows above the floor enabled the proto-plant to fuel its continuous increase in size.
“Science has always had a difficult time explaining how and why the earliest forms of multicellular life got big. This research helps to explain how we moved from a world ruled by microscopic bacteria to our world today where animals and plants dominate,” Laflamme explains.
“The new methods used in our research may also help to explain how multicellular life competed during the Cambrian explosion of complex animals,” the researcher concludes, quoted by Astrobiology Magazine.