It happens when I’m on the couch. The wood stove is either on or off. An inane advertisement comes across the TV screen. I got Smartfood dust all over my jeans. I turn the TV off, hitting the glowing red remote control button that says “power” with enough force to let the world know I’m saturated. I go to the window (the portal to the outside), and look at the bird feeders in the yard, the big trees beyond.
Nature is a mystery. Nature to me is not knowing what you’re looking at and being OK with that. Some of us don’t need to know quite as many whys. But some whys are good to know. A tree is the sea and the sea is me. My hemoglobin tells me so.
But the truth is that I don’t understand how photosynthesis really works. Plants make oxygen and absorb carbon dioxide. They use the energy from sun. The oxygen is a free gift from plants. On their leaves are tiny doors that open and close, letting a molecule of this go out, a molecule of that come in. Chlorophyll—it’s green– we all understand to be vital without really knowing why. Life goes on, one click at a time, the Web, a yoga studio, a busy turnpike. We breathe, the rise and fall.
Land plants tend to be conspicuous. The oak tree in your back yard. The fields of sedges, cat tails, herbs along that turnpike. In the sea, plants become mostly small. Most don’t flower. Many are loosely termed phytoplankton, the smallest microplankton. One group represents some of the oldest living things on earth—bacteria that act like plants. This group made up of blue-green algae, called cyanobacteria, have been found in the fossil record going back 3.5 billion years, making them the orginal photosynthesizers.
Within this hardy, trend-setting group is the most common creature on earth, numbering in the trillion trillions. That’s a lot of oxygen given out and a lot of carbon taken in. What’s crazy is that this organism—an oxygen producing bacterium called Prochlorococcus—wasn’t known until 1986. That’s how tiny it is. Another crazy thing is that this plankton is thought to be responsible for 20 percent of the oxygen that you and I breathe. One out of every five breaths we take no matter where on earth we are breathing, Kansas to south central Siberia, is because of Prochlorococcus —Amen to that.