Because plants produce their food with the sun. And everything eats plants, in someway. (A tiger eats a zebra who eats grass who get their food because the sun shines).
the sun
the sun is the beginning of all food chains
The Sun
The sun is the primary source of energy in most ecosystems. Through photosynthesis, producers like plants and algae convert sunlight into chemical energy, which is then consumed by herbivores, carnivores, and other organisms in the food web. Without the sun, the production of energy-rich organic compounds at the base of the food web would not be possible.
In most food webs the Sun is the ultimate source of energy. Some food webs start with chemotrophs and in those cases the source of the energy are chemicals often from underwater volcanoes.
Ultimately, the energy that drives a food chain is solar energy. Plants absorb and convert this energy, which insects, birds, and other herbivores transfer up the food chain until it reaches humans.
The sun is the source of all energy in a food web. The primary producers - plants - use the sun's energy to produce organic compounds. Some producers eg micro-organism use inorganic chemical reactions to produce energy
Plants use energy from the sun to produce their food( gulcose) in a process called photosynthesis . When animals eat these plants , then other animals eat animals that eat those plants , there you have a life cycle that has the sun as a base source of energy.
plants
Sun, Tree, Insect, Lizard, Snake, Hawk
Templeton, the rat in "Charlotte's Web," went to the dump to find words on discarded signs and food scraps to eat. The dump was his main source of sustenance and entertainment.
The energy from the sun!