Carbon dioxide, methane, nitrogen, ammonia, hydrogen and water vapor (note: no oxygen)

The role of spark discharge: simulating lightning on primitive Earth

The conclusion is that under certain conditions, various components in the original atmosphere can be converted into small organic molecules.

Small organic molecules─→organic macromolecules

Organic macromolecules──→primitive life

Fossils are the remains, relics and relics of ancient organisms preserved in the earth's strata

The most direct evidence of biological evolution: fossils

Homologous organs

Cytochrome c

The fossils of simpler and lower organisms always appear in the older strata; the fossils of the more complex and higher organisms always appear in the more recently formed strata.

From single cells to multi-cells, from low to high, from simple to complex, from aquatic to terrestrial

Creatures on earth generally have strong reproductive capabilities

Organisms will fight for survival, such as necessary food and living space.

Inherit beneficial mutations to the next generation

Survival of the fittest and elimination of the unfit

forest ape

Australopithecus could walk upright on two legs

The brain capacity of Homo habilis is larger than that of Australopithecus apes, and the sulci and gyri of the brain are similar to those of humans. It may have language ability.

Homo erectus was the first to use fire, hunt, run, make stone tools, and have the ability to speak

Homo sapiens wore animal skins and used simple tools such as javelins and spears.