What facts testify to the unity of the origin of all living organisms?

All living organisms on our planet are relatives. This is evidenced by several factors:

1.Embryonic evidence: In the early stages of development of embryos of different animals, it is easy to notice their similarity in structure.

2. Anatomical evidence: all living organisms have the same organs or organ systems, such as excretory, modes and organs of movement, digestive organs. The only difference is the degree of development of these organs or systems.

3. Morphological evidence: organisms belonging to the same systematic group have similar body parts. For example, all arthropods have a head, chest, and abdomen.

4. Archaeological evidence: Scientists have found similarities in structure between the fossil form of living organisms and living organisms.