The autotrophs are the first true organisms on the planet Earth. The very first of them, the first prokaryotic life on earth, were chemotrophs. Chemotrophic organisms utilise reactions with inorganic chemicals to generate the energy they need to survive. They were followed by other autoptrophs – lithotrophs, a more specialised form that rely on minerals, and phototrophs, the earliest photosynthetic organisms.
These organisms were the common origin of all life on Earth, from single-celled bacteria that have not really changed that much in millions of years, to every multi-celled organism on the planet. Even you.
The Big Bang Theory — Barenaked Ladies