The Strength of Darwin's Theory

It explained data better than previous explanations

Variation

Lack of perfection

Developmental similarities

Not all similarities the same

Homologous vs analogous similarities

Sexual dimorphisms

It also makes specific, testable predictions

All life should have some elements in common

Species should exhibit differing degrees of similarity

Should never see a "frog/mushroom"

We have tested the predictions from evolution for well over a century

The pattern is clear.

Life looks as if all species are related