Biology Tutorials > The Origins of Life > Geological Periods

Geological Periods

Geologic time scale (GTS), a system of chronological dating used to show events that have occurred in Earth’s history

Table of Contents

Precambrian Times (Most Ancient)

All time before life existed, Earth was still a volatile environment, though the origins of life came around during this period.
• Origins of Life on Earth
• First Life on Earth
• Cell Development & Diversification

Cambrian Period

The development of multi-cellular organisms, including sponges, primitive animals, and various plant life, diversifying from old species
• Multicellular Organisms
• Primitive Animals

Ordovician > Permian Periods

The transition from primitive species to specialized organisms, the increasing of genetic diversity via sex, and the transition from sea to land
• Arthropods
• Insecta – One of The Arthropods
• Fish

Triassic / Jurassic Periods

The arrival and dominance of dinosaurs in the air, land, and sea, and how they developed from their ancestors and the causalities of their existence
• Amphibians & Early Reptiles
• The Dinosaurs

Cretaceous Period

The removal of dinosaurs from planet Earth and the emergence of mammals and other more complex organisms
• Dinosaur Extinction
• Mammals Ancestors

Tertiary Period

The evolution of man and further diversification of all species to the present date. The transition of Neanderthal man to modern man.
• Early Mammals
• The Hominids

Quaternary Period

The evolution of man and further diversification of all species to the present date. The transition of Neanderthal man to modern man, and how our dominance of planet Earth has directly shaped the future timeline of planet Earth.
• The Homo Species