Ecosystems: How Living Things Depend on Each Other

Hi explorer, I am Atlas! Look around this meadow with me. An ecosystem is a place where living things and their environment interact as a system. Living things are plants, animals, and tiny creatures. The environment is the nonliving parts — sunlight, water, air, and soil — that living things depend on. Every living thing needs resources to survive. Plants need sunlight, water, air, and soil. Animals need food, water, air, and a safe shelter to live in. Here is the cool part: plants are the only ones that can make their own food. They take in sunlight, water, and carbon dioxide from the air through tiny pores in their leaves, and use all three to build sugar for energy. That is why plants are called producers. Animals cannot make their own food, so they eat. A rabbit eats grass. A hawk eats the rabbit. The grass got its energy from the sun — so energy flows from the sun, to plants, to animals in one direction. There is also a return path. When an earthworm breaks down dead leaves, it puts nutrients back into the soil so new plants can grow. Energy flows forward through the food chain; matter cycles back through decomposers like earthworms. This means every living thing depends on the others. If the grass disappeared, the rabbit would have no food, and the hawk would lose its meal too. Everything is connected. If you ever feel stuck, just follow the energy: start at the sun, go to a plant, then to the animal that eats it.