Origin of Life and Evidences of Evolution

Oparin-Haldane Hypothesis

The theory that life originated on Earth through a gradual process of chemical evolution, where simple inorganic molecules formed complex organic molecules, which then organized into self-replicating structures.

Chemical Evolution (Chemogeny)

The process by which simple inorganic molecules on early Earth combined to form complex organic molecules, leading to the building blocks of life.

Biogeny

The origin of living organisms from other living organisms (in contrast to abiogenesis).

Homology

The similarity in structure between organs of different animals that arises from a common evolutionary origin, despite differences in function.

Analogy

The similarity in function between organs of different animals that arises from convergent evolution, despite differences in structure and evolutionary origin.

Fossils

The preserved remains or traces of organisms from a past geological age, found embedded in sedimentary rocks.

Paleontology

The scientific study of fossils to understand the history of life on Earth.

Vestigial Organs

Organs that are present in an organism but are reduced in size and have lost their original function over evolutionary time.

Atavism

The reappearance of a lost ancestral trait in an organism, usually due to the expression of genes that were suppressed for many generations.

Divergent Evolution

The process by which two or more species evolve increasingly different traits from a common ancestor, often due to different environmental pressures.

Convergent Evolution

The process by which unrelated organisms independently evolve similar traits or adaptations due to similar environmental pressures or lifestyles.