Imagine being able to sunbathe all day long. But instead of getting a nice tan to show off… You turn green! And get lazier.

Don’t worry. It’s not the end of the world. In fact, this might be the first time that humans actually save the planet. Unlike humans, plants don’t have mouths.

Well, most of them don’t. But despite not eating any food, lots of plants can grow bigger and stronger than any of us!

And they don’t even have to get angry. That’s because, through a process known as photosynthesis, plants are able to convert water, minerals, and sunlight into energy.

But photosynthesis insn’t just a process that feeds plants, it’s also the reason you’re still breathing. And why everything on this planet hasn’t been fried to a crisp!

Imagine you could do it too? What would the world look like if humans could photosynthesize?

The world would be very green. To be able to photosynthesize, an organism needs chloroplasts. Chloroplasts are tiny, tiny organelles that are filled with, well, chlorophyll, a photosynthetic pigment that captures and converts energy from the Sun.

It’s also what makes plants green. And it would make all humans green too. It might not be your color, but is it a price you’re willing to pay for a life of sun bathing and leisure?

The way plants photosynthesize is by absorbing water and minerals through their roots in the soil. These nutrients travel to the plant’s leaves, which are full of pores that absorb carbon dioxide from the air around them.

With a bit of sunlight, the chloroplasts work their magic and convert the absorbed water, minerals, and carbon dioxide into glucose, the same sugar that humans rely on for energy. A major difference, however, is that we require a lot more energy than plants do.

In one day, a good dose of sunlight might give a tree as many as 200 calories. But a healthy human needs about 2,000 calories each day to survive!

And while plants are naturally environmentally friendly, they’re certainly not efficient. Just 5% to 10% of the sunlight they receive gets converted into energy.

So if humans are going to photosynthesize, we’d better get good at it. We would probably evolve to become a lot bigger to absorb enough light to feed and grow.

And just to get the right amount of daily calories, we’d probably have to lie out in the sun all day, and do little else. With any luck, we might evolve to start growing leaves, which would make the process a little easier, and provide us with a little shade. But our bodies would have to be 100 times more porous, just to absorb the amount of CO2 we’d need.

Shade or no shade, with all those extra pores, there will be a lot more sweat trickling down our bodies. On the plus side, we’re sweating out oxygen so the air will smell pretty clean and fresh! Which is a nice change from…

In fact, with everyone photosynthesizing, we’ll all be absorbing the harmful carbon emissions that would otherwise be eating away at our ozone layer.

So not only do you get to sit back, relax, and catch those rays, you can take a bit of credit for saving the planet. How long would we last with nothing between us and the sun?

Subscribe to What-If on Youtube or follow the show on Facebook Watch.

Notify of

Inline Feedbacks
View all comments