Life began on Earth at least 3.5 to 4 billion years ago, and it has been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later, the first multicellular organisms evolved, and after that, Earth's biodiversity greatly increased.
Evolution is responsible for the change that has occurred to life on earth from the beginnings of the planet until today.
The evolution of the horse is one illustration. The dawn horse (genus Hyracotherium), which lived more than 50 million years ago, was an animal the size of a dog with multiple toes on each foot and teeth suitable for browsing.
Modern living things have descended from extinct ancient life forms, which are how evolution explains how living things are changing today. Living things typically become more environment-friendly as they develop. Due to their evolving adaptations.
