Until Now
BiologyGeology

The oldest red algae

Fossils in Indian rock preserve cell interiors so well that chloroplasts are visible.

When
Known to
± 50 million years
Era
Mesoproterozoic, Proterozoic

Thread-like and lobed fossils from 1.6-billion-year-old Indian phosphorites retain three-dimensional cellular and subcellular structure, including regularly arranged internal bodies interpreted as chloroplasts. They are argued to be crown-group red algae, which would make them the oldest plant-like organisms known and push the eukaryotic tree's major branches far back into the Mesoproterozoic.

Just before

Just after