Question

What is an evolutionary tree? Is there a precise evolutionary tree that explains the emergence and origin of every type of living organisms?

Answer 1

An evolutionary tree is the pictorial and schematic representation of the evolutionary relationship between species of living organisms. Its trunk (or a preceding branch) represents the common ancestors of a species, and groups of living organisms are distributed along its branches according to the hypothesis on their origin.

For example, today we acknowledge that birds and mammals are two distinct branches of the same preceding reptile branch.

Biology cannot provide a definitive evolutionary tree (phylogeny) for all species of living organisms that live or have lived on our planet.