Why are earthworms valuable to a farmers?

Earthworms play an important role in the creation of healthy, productive "living" soils. Without them, we couldn't eat vegetables and fruits!! Or even breathe! Because they help trees!

The early ancestors of the earthworms were partly responsible for ending the global ice age billions of years ago. The relentless burrowing deep in the ocean floor, where the wastes & fossils of organisms accumulated within the sediments, spawned the recycling of carbon nutrients and the formation of carbon dioxide gas. The collective release of CO2 into the Earth's atmosphere generated a greenhouse effect which inevitably warmed the planet to habitable temperatures for later descendants.