Scientists have discovered plant fossils that date back 1.6 billion years, hundreds of millions before advanced life was thought to have evolved.
The ancient rocks were discovered in central India and point to red algae that lived in a shallow sea, according to the study’s authors.
“You cannot be a hundred per cent sure about material this ancient, as there is no DNA remaining, but the characters agree quite well with the morphology and structure of red algae,” said Stefan Bengtson, professor emeritus of palaeozoology at the Swedish Museum of Natural History.
Life on Earth is believed to have formed between 3.5 and 4.3 billion years ago as single-celled organisms that lacked nuclei and other organelles.
The oldest, previously discovered red algae, multicellular organisms that did have organelles, were thought to date back 1.2 billion years.
“The ‘time of visible life’ seems to have begun much earlier than we thought,” Bengtson added.
Large multicellular organisms with organelles are believed to have developed much later – around 600 million years ago.
The red algae were found inside Indian phosphorite in exceptionally well-preserved sedimentary rocks in Chitrakoot, central India.
Therese Sallstedt, who was a doctoral student at the time, first identified the organism’s more complex structures, including what are believed to be parts of chloroplasts, which process photosynthesis.
“I got so excited I had to walk three times around the building before I went to my supervisor to tell him what I had seen,” Sallstedt said.
Earlier this month, UCL researchers claimed to have discovered the oldest ever traces of life on Earth, which could date back as far 4.28 billion years.