Sensorimotor Stage: This is the very first stage of Jean Piaget's theory of cognitive development. The sensorimotor stage starts from birth and lasts around two years of age.
Object permanence is considered to be the important attainment of this stage and states that an object exists even if it is not in a person's visibility or hidden. Through object permanence, a person can develop mental representation that is schema of a particular object.
The earliest stage would be the sensorimotor stage.
Answer: The change a terrestrial ecosystem experiences as it recovers from a disturbance depends on the intensity and magnitude of the disturbance. The major mechanisms of recovery in such ecosystems are primary and secondary succession.
