Through the examination of bacteria living beneath the seafloor, a new study suggests that evolution may be possible without reproduction.
Led by Professor William Schopf, a palaeobiologist at the University of California Los Angeles, a new study hypothesizes that if a well-adapted organism’s physical environment is not changed its biology also remains unchanged. The team of researchers published their findings in the Proceedings of the National Academy of Science, after examining a number of preserved fossils of bacteria that lived in the mud of what is now Western Australia nearly two billion years ago.
“These microorganisms are well-adapted to their simple, very stable physical and biological environment,” wrote Schopf adding, “It seems astounding that life has not evolved for more than 2 billion years—nearly half the history of the Earth.”
Modern vs preserved fossils of microorganisms: Time to compare
The examined fossils were found in an area now referred to as Duck Creek near Nanutarra, Western Australia. They were compared to modern microbes off the coasts of Chile, Peru, Costa Rica, Panama and Ecuador and the researchers found that they were genetically identical.
“In form, function and metabolism, they are identical,” Schopf said.
The bacteria, which are capable of photosynthesis, thrived in sulfur heavy environments before oxygen levels rose to today’s numbers and consequently had no trouble living well beneath the ocean’s floor.
“There is no turning of sediments, things don’t get stirred up, there is no oxygen at all — they get no time signal, there is no change,” said Schopf.
Speaking to the fact that microbes reproduce asexually, Shopf added that, “They are well adapted for their environment, and there isn’t any competition.”
Schopf and his team also posited that there are likely similar organisms living beneath the bottom of each of the world’s oceans but that finding them is prohibitively expensive and difficult as the depths of the oceans can be quite staggering making for a daunting endeavor.
“I suspect that is an environment that hasn’t changed much over the history of the Earth,” he said.