Answer:
Following are the general steps which lead to the evolution of the human eye:
- There were certain light- sensitive spots on the body of certain organisms which helped them to drive off the predators.
- With the passage of time the light-sensitive part was deepened to allow the formation of a pit which enabled vision.
- The opening of the pit narrowed, forming an aperture like structure.
- The light- sensitive spot then evolved into retina.
- With the passage of time, lens formed at the front.
- With the passage of time, other structures were formed.