8, 9. How is Jehovah’s wisdom revealed in the cycles that sustain life?

8 Jehovah’s wisdom is revealed in the cycles that sustain life on earth. To illustrate: Imagine living in a densely populated walled city that had no way of importing fresh water or exporting waste products. Such a city would soon become filthy and uninhabitable. In some respects, our earth is like that walled city. It contains a finite amount of fresh water, and we can hardly export waste products into outer space. This “walled city,” however, is able to support billions of creatures, generation after generation. Why? Because of its amazing ability to recycle or exchange the products vital for life.

9 Consider the oxygen cycle. Billions of creatures take in oxygen and give off carbon dioxide. Even so, the supply of oxygen never runs out, and the atmosphere never becomes choked with the “waste” gas, carbon dioxide. Why not? The answer is found in an amazing process known as photosynthesis. Using this process, green vegetation takes in carbon dioxide, water, sunlight, and nutrients and produces carbohydrates and oxygen. When we take in oxygen, we complete the cycle. In a literal way, Jehovah uses the vegetation that he designed to give “to all persons life and breath.” (Acts 17:25) What remarkable wisdom!

10, 11. How do the monarch butterfly and the dragonfly reveal Jehovah’s brilliance?

10 Jehovah’s brilliance is also revealed in the multitude of creatures that inhabit our remarkable planet. Estimates of the number of species on earth vary from 2 million to 100 million. (Read Psalm 104:24.) Note the wisdom evident in the design of just some of these creatures.

God’s wisdom is seen in the design of the dragonfly’s eye; inset shows a magnified view (See paragraph 11)

11 The monarch butterfly, for example, has a brain that is only about the size of the tip of a ballpoint pen. Yet, that butterfly has the ability and skill to migrate some 1,800 miles (nearly 3,000 km) from Canada to a particular forest in Mexico, using the sun to help it navigate. How does it manage when the sun shifts across the sky? Jehovah designed its minute brain with the ability to compensate for the sun’s movement. Or consider the eye of the dragonfly. This creature sees by means of two compound eyes. Each eye has some 30,000 individual lenses. Even so, the dragonfly’s tiny brain is able to decipher the signals transmitted from all those lenses and detect the slightest movement in its environment.

12, 13. What impresses you about the way Jehovah has designed the cells that make up your body?

12 Even more impressive is the way that Jehovah designed the cells that make up all living creatures. Your body, for instance, is made up of about 100 trillion cells. Inside each of those cells is a tiny ropelike structure known as DNA (deoxyribonucleic acid). It stores most of the information needed to build your entire body.

13 How much information does DNA contain? Compare the storage capacity of one gram of DNA with that of a compact disc (CD). A CD can store all the information contained in a dictionary, which is impressive considering that a CD is merely a thin disc of plastic. However, just one gram of DNA can store as much information as one trillion CDs! To put it another way, a single teaspoonful of dried DNA can store enough information to build 350 times as many humans as are alive today!

14. How do the discoveries made by scientists make you feel about Jehovah?

14 King David described the information needed to build a human body as being written in a figurative book. Speaking of Jehovah God, he said: “Your eyes saw even the embryo of me, and in your book all its parts were down in writing, as regards the days when they were formed and there was not yet one among them.” (Ps. 139:16) Understandably, David was moved to praise Jehovah when he considered the way his own body was created. The discoveries made by scientists in recent years have only added to the awe we feel when we contemplate the way that Jehovah made us. These discoveries give us added reason for agreeing with the psalmist who wrote of Jehovah: “I shall laud you because in a fear-inspiring way I am wonderfully made. Your works are wonderful, as my soul is very well aware.” (Ps. 139:14) Really, how could people not see that creation reveals the existence of a living God?