Animals That Eat Light

Nature has created animals that eat light from sunshine, the way plants do. The process, of course, is called photosynthesis.

Whether under the control of God—as I and many of my readers will always believe for powerful reasons that have nothing to do with science—or not, it is apparent that nature has created animals that eat light ... they get at least some of their energy from photosynthesesis.

Now scientists are trying to follow suit.

The New Scientist articles that describes this requires a free membership to be read, so I'll be a little more detailed in this description than I will in most of my evolution articles. That way you won't have to sign up and read it unless you want to. New Scientist does have a lot of interesting articles for laymen, so the free membership is not to be regretted.

Borrowing the Ability to Photosynthesize

No one can be sure yet, but it's possible that the most successful organism in natural history is the mitochondria. It is entirely possible that mitochondria were once their own distinct species, but their ability to produce energy was borrowed ... by every living cell.

Every living cell has a component called a mitochondria. Some cells have more. (You can increase the amount of mitochondria in your cells by exercising.)

The mitochondria are the powerhouses of your cells. They take the sugar you eat (or the sugar produced from the complex carbs and fats that you eat) and turn it into the energy your cells need for all their various functions.

Mitochondria, however, have their own DNA, separate from the DNA in the nuclei of your cells. This is the "mitochondrial DNA" that you inherit directly from your mother. It's not mixed with your father's DNA, like your nuclear DNA is. It is this mitochondrial DNA, which mutates at a known rate, that was used to come up the "mitochondrial Eve" theory, in which we also descended from one woman in Africa about 150,000 years ago.

Because mitochondria have their own DNA, some scientists have argued that they used to be their own separate species before they were incorporated into another cell, the singular most successful survival strategy in natural history.

Plants, like our cells, evolved in the same way. Rather than developing their own ability to eat light, or photosynthesize, they captured cyanobacteria and used the cyanobacteria's "technology" to obtain energy from sunshine.

I don't know how you react to that, but something about those stories thrills me. I love the way nature works, and because that wonderful, deep part of us that wants to worship in awe at the majesty that is nature still works in me, it makes me want to praise God.

Scientists Try to Learn from Nature

Scientists are always trying to learn from nature. Our cells didn't bother figuring out how to create energy on their own. They simply borrowed from mitochondria. Scientists have begun to see what a great idea this is.

A great example is geckos.

We already know how to use suction to clink to walls and windows. We hang holders for our soap and puffs in our showers using little rubber suckers, for example. However, suction only works so well, and it only works on smooth surfaces. Suction is also a poor way to climb because you have to have a way to release the suction with every movement upwards.

Geckos, however, don't use suction to climb anywhere they want and even to hang upside down. Instead, it turns out that they have thousands of tiny hairs so microscopically small that they fit between the molecules of surfaces that they cling to.

This amazing "technology" is being borrowed by scientists who are attaching nanofibers to the "feet" of small, quadruped robots that can climb anything, though we're not as good at it as nature ... yet.

"Creating" Animals That Eat Light

Scientists are also trying to reproduce the evolutionary process that produced photosynthesis in plants.

A research student at Harvard Medical School in Boston, Christina Agapakis, injected cyanobacteria into zebrafish eggs. Mostly, she just wanted to see if the cyanobacteria would survive, but when they did, the question arose as to whether they might give the zebrafish the ability to photosynthesize—to use sunlight to provide part of the energy they need for living.

So far, the experiment hasn't worked, at least in producing energy. Even when they genetically modified the cyanobacteria to export sugar, the zebrafish got little or none of it.

Scientists are hopeful, though. There are numerous animals with such a symbiotic relationship with algae. The most amazing is the spotted salamander (Ambystoma maculatum). It stores algae in its oviducts, then passes them on to its eggs. Interestingly, the algae are not just on the outside of the eggs. They enter the eggs, and the mitochondria in the eggs cluster around the algae, obviously obtaining oxygen needed to burn sugar from the algae.

Scientists don't understand how that's happening yet, but nature has found amazing ways to use photosysynthesis. Some animals even have small tubes that channel light deep down inside themselves to feed photosynthesizing cells. So some animals are catching sunshine and channeling it down inside themselves before they eat it!

Eating Light

One of the most amazing things about the creation is something I learned from a children's book, then verified later in more authoritative sources.

All of us eat light.

All of our energy, directly or indirectly, comes from sunlight.

Humans, for example, eat plants to get the energy from them that they have gotten from sunshine. Even when we eat animals, we are eating creatures that have eaten plants that have gotten their energy from light.

Thus, one way or another, we are surviving by eating light, as all creatures do.

Well, almost all. As we get better at discovering life, we have found microorganisms that obtain energy from heat that comes from the center of the earth. Deep in caves, up to two miles below the earth, and deep in the ocean, huddled around hydrothermic vents, are creatures working with chemistry that is strange and unfamiliar to us, capturing heat from the earth's core to survive upon.

At least on theory of abiogenesis (the study of the origin of life) is based upon that process, but that's for other parts of this site.

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