As shown in the diagram, dead plants and animals are broken down by bacteria and transformed into minerals. This organic waste absorbed into the soil constitutes the basic foodstuff of plants. This nutritional cycle is therefore of vital importance for all living things.
In the above verse, our attention is drawn to a food cycle of which people at the time of the Qur'an's revelation could have known nothing.
When a living thing dies, micro-organisms quickly cause it to decompose. The dead body is thus divided up into organic molecules that mix with the soil and form the basic source of food for plants, animals, and, ultimately, humanity. Were it not for this nutritional cycle, life would not be possible.
Bacteria are responsible for meeting all living things' mineral and food needs. Plants and some animals, which remain almost dead (hibernation) throughout the winter, revive in the summer and meet all of their mineral and food requirements through the activities of bacteria during the winter. Throughout the winter, bacteria separate organic wastes (i.e., dead plants and animals) and turn them into minerals.162 Thus, when living things reawaken in spring, they find food ready and waiting for them. Thanks to bacteria, a "spring cleaning" has been carried out in their environment and the necessary amount of food has been prepared for nature as it returns to life in the spring.
As we have seen, dead creatures play a vital role in the emergence of new ones. This transition, indicated in the Qur'an as "He brings forth the living from the dead, and produces the dead out of the living," is carried out in the most perfect manner. This is one of the proofs that the Qur'an is the Word of Allah.