Question

How embryology of animals give evidences of organic evolution?

Answer 1

1. Embryos of different vertebrates (fish, salamander, turtle, bird, dog, human) have remarkable similarity during early stages of development, making them difficult to distinguish. This indicates they evolved from a common ancestor.
2. Embryos of higher vertebrates resemble the adult forms of lower vertebrates during development, showing a recapitulation of evolutionary history.
3. All vertebrate embryos possess structures such as the notochord and gill clefts during early development. Notochord is replaced by the vertebral column, and gill clefts either persist or disappear, depending on the species, indicating shared evolutionary origin.
4. Development of organs like the heart in vertebrate embryos passes through stages that reflect their evolutionary progression, such as the transition from two-chambered hearts in fish to four-chambered hearts in birds and mammals.