Saves them from rushing after prey, they way animals would...
But there is a slug in the deep sea that found a better way:
Its food are bright green algae, and it steals their DNA!
Researchers have established the most amazing fact:
The algae's genes the slug incorporates in its digestive tract,
And, like a plant, by photosynthesis for months on sunlight thrives,
When a lack of proper food would not keep it alive!
Oh! What a neat and useful trick it surely might have been.
If Man could but use chlorophyl – by turning himself green.