History of Life

Scientific Theory

A well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.

Abiogenesis

The formation of organic molecules from inorganic molecules, leading to the origin of life.

Fossil Record

A historical record of life forms preserved in sedimentary rock layers, providing insight into the history of life on Earth.

Evolution

The cumulative changes that occur in a population of organisms over time, explained by descent with modification.

Plate Tectonics

The theory explaining the movement of the Earth's lithosphere, consisting of large plates that have been slowly moving for billions of years.

Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Endosymbiosis

A hypothesis that describes how prokaryotic cells engulfed smaller cells, leading to the evolution of eukaryotic cells.

Mass Extinction

A significant event in which a large number of species become extinct in a relatively short period due to environmental changes.

Adaptive Radiation

Periods of evolutionary change when groups of organisms form new species to fill different ecological roles in their communities.

Radiometric Dating

A method of dating fossils by measuring the decay of radioactive isotopes within them.