Comparing and contrasting embryos of different species is called

Comparing and contrasting embryos of different species is called Comparative embryology.

Explanation:

It is the branch of embryology where embryos of different specie are compared to find out that how two special are evolutionary similar or different from each other. It also helps in the identification of organism's closest ancestor. For example: When Aristotle observed embryos of different animal specie, he described that egg laying (oviparous) organisms are different from birth giving (viviparous) organisms. This has a connection with organism's developmental pattern which tell that both organisms have different or common ancestry.

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