Scientists Offer First Definitive Proof for Bacteria-feeding Behavior in Green Algae

A black and white image of microorganisms on a slide. The superimposed letters d, g, v, p, and m, are distributed throughout.
This transmission electron micrograph shows bacteria-feeding in the green alga Cymbomonas. 

A team of researchers has captured images of green alga consuming bacteria, offering a glimpse at how early organisms dating back more than 1 billion years may have acquired free-living photosynthetic cells. This acquisition is thought to have been a critical first step in the evolution of photosynthetic algae and land plants, which, in turn, contributed to the increase in oxygen levels in Earth’s atmosphere and ocean and provided one of the conditions necessary for animal evolution.