Scientists in India have uncovered a pair of 1.6 billion-year-old fossils that appear to contain red algae, which may be the oldest plant-like life discovered on Earth.
Until now, the oldest known red algae was 1.2 billion years old, said the paper in the journal PLOS Biology .
Scientists often debate the question of when complex life began on Earth, but they generally agree that large multicellular organisms became common about 600 million years ago. This discovery could lead experts to rewrite the tree of life, said lead author Stefan Bengtson, Professor Emeritus of palaeo-zoology at the Swedish Museum of Natural History.
“The ‘time of visible life’ seems to have begun much earlier than we thought,” he said. The material structurally resembles red algae, embedded in fossil mats of cyanobacteria inside a 1.6 billion-year-old phosphorite, a kind of rock, found in Chitrakoot region in Uttar Pradesh and Madhya Pradesh. “You cannot be a 100% 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 Professor Bengtson. Scientists used x-rays to observe regularly recurring platelets in each cell, which they believe are parts of chloroplasts, the organelles within plant cells where photosynthesis takes place.
