burgeoned, they liberated vast quantities of oxygen (O2), which radiation in the upper atmosphere converted to ozone (O3), which in turn absorbed ultraviolet light and prevented much of it from reaching the earth’s surface Land life was now possible The challenging life of the plant Plants are rooted to one spot in the earth, where they absorb water and minerals from the soil, carbon dioxide and oxygen from the air, and light energy from the sun, and transform these inorganic materials into plant tissues — and into nourishment for insects and other animals Plants defend themselves against predators with a variety of chemical weapons, some of which also make them flavorful, healthful, or both In order to spread their offspring far and wide, some plants surround their seeds with tasty and nourishing fruits that animals carry away and eat, often spilling some seeds in the process So we owe our very existence as oxygenbreathing, land-dwelling animals to the greenery we walk through and cultivate and consume every day of our lives Why Plants Aren’t Meaty Land-dwelling plants that can nourish themselves still need access to the soil for minerals and trapped water, to the atmosphere for carbon dioxide and oxygen, and to the sun for energy All of these sources are pretty reliable, and plants have developed an economical structure that takes advantage of this reliability Roots penetrate the soil to reach stable supplies of water and minerals; leaves maximize their surface area to capture sunlight and exchange ... Land-dwelling plants that can nourish themselves still need access to the soil for minerals and trapped water, to the atmosphere for carbon dioxide and oxygen, and to the sun for energy All of. .. away and eat, often spilling some seeds in the process So we owe our very existence as oxygenbreathing, land-dwelling animals to the greenery we walk through and cultivate and consume every day of our lives...some of which also make them flavorful, healthful, or both In order to spread their offspring far and wide, some plants surround their seeds with tasty and nourishing fruits