World’s oldest red algae fossils found in India

A group of scientists in India unearthed a pair of 1.6 billion-year-old fossils that appear to contain red algae. It is estimated that it may be the oldest plant-like life discovered on Earth.

The study was published in March 2017 in the journal PLOS Biology. As per the paper, until now, the oldest known red algae were 1.2 billion years old.

Key highlights of the study

• The preserved fossils came from phosphorite deposits at Jankikund, Chitrakoot, Uttar Pradesh.

• The samples were analyzed by Professor Stefan Bengtson at the Swedish Museum of Natural History and co-authors.

• They discovered two kinds of fossils resembling red algae. One type is thread-like (named Rafatazmia chitrakootensis) and another consists of fleshy colonies (Ramathallus lobatus).

• The researchers looked inside the algae with the help of synchrotron-based X-ray tomographic microscopy.

• The rocks mainly consist of calcium and magnesium carbonates. However, the microbial mats and the fossils are preserved in calcium phosphate, which allowed the researchers to view the cellular and subcellular structures in three dimensions with the use of synchrotron-radiation X-ray tomographic microscopy.

• In addition, they also found regularly recurring platelets in each cell, which are believed to be parts of chloroplasts.

• Also, distinct and regular structures at the center of each cell wall were also found. It is rather typical of red algae.