“For as plants grow they are eaten by the animal and replace those elements which have been depleted in the latter’s body. In this manner the plants enter the animal kingdom. The microscopic organisms in the air, water, and food enter in turn the body of man and replace that which has been assimilated therein.“

– ‘Abdu’l-Bahá, Twelve Table Talks given by ‘Abdu’l‑Bahá in ‘Akká