Algae has many effects on human life, but its most important contribution is that it produces the majority of oxygen on earth, without which humans and animals would suffocate. Algae is also responsible for the number one fuel source in the world: oil.
Millions of years ago, algae grew in shallow lakes and riverbeds that are now miles below the earth's surface in the form of crude oil. This process occurred through the natural decaying of the algae that settled on the bottom of water beds, mixed with sediment and eventually became trapped under non-porous cap rock, where it decomposed into kerogen. This waxy, hydrocarbon-rich material combined with geological heat and pressure below the earth’s surface, resulting in the oil reserves that are drilled for fuel. Thanks to technological advances, this process can now be replicated in a matter of days, providing gasoline, biodiesel and jet fuel.
Algae also helps to purify water by combining with human waste added to bodies of water. The algae breaks down the waste, turning it into nitrogen, which releases oxygen that purifies the water.
It is also used in a variety of foods, such as hamburgers, yogurt, and ice cream.
Algae is also believed to have many medical benefits. Algae may prevent and treat chronic fatigue, colds, arthritis and chronic allergies, and it may have anti-cancer benefits.