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Science

Theories of evolution

Similarities and differences

Different organisms can be classified by studying their similarities and differences. These studies also help us to understand the evolutionary relationships between different organisms.

Evolutionary trees

Evolutionary trees are used to represent the relationships between organisms. The diagram shows an evolutionary tree.

A cladograph

An evolutionary tree

In this evolutionary tree, species A and B share a common ancestor. Species F and G share a common ancestor, which itself shared a common ancestor with species E. All seven species share a common ancestor, probably from the distant past.

Back to Evolution index

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