Where do green plants get their chloroplasts, those tiny “sacs” inside a leaf containing chlorophyll, the food producers of a plant? The answer may surprise you.

Bacteria.

We know that plant photosynthesis supports life because what plants “breathe out” (oxygen), we breathe in, a sublime example of the interconnectedness of life on this planet. But here’s the amazing part: chloroplasts trace their ancestry to a form of bacteria known as cyanobacteria. Through a long process, these bacteria evolved and differentiated into organelles or specialized “sacs” such as chloroplasts. Therefore, cyanobacteria are the true the pioneers of photosynthesis. They were alive early in our planet’s history when the earth was oxygen poor. In their trillions, and through their own version of photosynthesis, they released tons of oxygen into the atmosphere, the rivers, the seas. And they also played an important role in the Great Oxygenation Event some 2.4 billion years ago during which oxygen levels on the earth rose dramatically for reasons that aren’t entirely clear.

In short, while we owe a huge debt to plants, we also ought to say a big thank-you to cyanobacteria for endowing plants with chloroplasts in the first place, which brings the level of interconnectedness on our amazing planet one level deeper.

TED Talk: “Everything is Connected: Here’s How”

Extracts of TED talk by Tom Chi (inventor, investor and thought leader) who elaborates on the role of cyanobacteria in oxygenating the earth.

Tom Chi describes himself as an inventor, thought leader, coach, speaker and investor. He was trained as an astrophysicist and has worked as a product innovator with Google, co-founding the user research function of GoogleX, Google’s famed innovation lab. He now spends his time developing practical tools for individuals and teams to solve problems in a way that makes a positive impact on climate and the environment. His has a website at www.tomchi.com.