Evolution of Life

Evolution of life in different eras

Paleontological evidence (evidence from fossils) shows that evolution has occurred. By the study of fossils, it is known that 570 million years ago, there was not suitable condition for living organisms on the land to evolve but some single-celled organisms were originated in oceans.

The oldest plant was originated about 320 million years ago and the invertebrate animals were originated about 120 million years ago. But the first organism was bacterium that was originated before 380 million years ago.

The oldest plant was originated about 320 million years ago and the invertebrate animals were originated about 120 million years ago, in Archeozoic and Proterozoic Era respectively.

Invertebrates, vertebrates, fast growing bushes and giant fern trees were developed in Paleozoic era. Paleozoic Era is also called time of amphibian because amphibianswere dominant in this era.

Mesozoic era is also called the time of reptiles because reptiles were abundant in this era. The first dinosaur was formed about 225 million years ago but was extinct during the Cretaceous period. The first bird and mammal were formed around this time.

Cenozoic era is the present era which is called the"time of mammals". In this time, primates and horses were formed about 54 million years ago and rhinoceros and camel like animals were formed about 38 million years ago. The earliest man was formed about 2 million years ago. Thus, man, who is ruling on the earth by his intelligence, is the youngest on the earth.