Evolution of Major Life Forms

Earth is about 4.5 billion years old. In its early days, it was a hot, rocky planet. But over time, it cooled, making life possible.

The first life forms were tiny, single-celled organisms that appeared around 3.5 to 4 billion years ago.

Then, about 3 billion years ago, some organisms developed the ability to use sunlight to produce food through photosynthesis, releasing the oxygen we breathe today.

Around 2 billion years ago, complex cells with a nucleus, known as eukaryotes, appeared, leading to multicellular organisms.

Around 600 million years ago, simple animals appeared, followed by arthropods, fishes, and land plants.

Next, amphibians moved from water to land about 360 million years ago, and reptiles appeared 300 million years ago.

Dinosaurs ruled around 200 million years ago. But they vanished 65 million years ago, allowing mammals to flourish.

Birds evolved from certain dinosaurs, and flowering plants appeared around 130 million years ago.

Finally, modern humans appeared about 200,000 years ago to write the latest chapter in Earth’s story!