[Image: An animal that looks like a plant. From simple.wikipedia.org/wiki/Stick_insect#/media/File:LeafInsect.jpg.]
Future genetic engineering may create animals that can photosynthesize like plants. These animals would require less food because they will make some of it from sunlight. In principle, even humans could be modified this way!
There are already some natural cases of animal-plant integration. Some marine flatworms have algae living in their translucent bodies,between their cells. Increasing the degree of plant-animal integration further, the method used by coral and various other marine animals is to have symbiotic algae living, not between their cells (like the flatworms), but actually inside some of their cells. The algae are typically of the genus Symbiodinium, and live in “symbiosomes,” blobs inside the animal cells that hold the algae separate from the rest of the cell. Each symbiosome is a kind of really, really tiny terrarium (a “nanoterrarium”) maintained by the finely engineered nanotechnology device of nature we call the cell. The cells supply the algae, in its symbiosome home, with basic chemicals and exposure to light. In return the algae produce nutrients that the animals extract from the symbiosome and use. In coral, when these algae die the coral loses color and, if not reversed, itself dies in the phenomenon called “coral bleaching.”
