Heterochrony is ... an evolutionary change in the rate or timing of developmental events an evolutionary change in gene sequences an evolutionary change in gene regulation an evolutionary change in spatial pattern g

Heterochrony refers to an evolutionary change in the rate or timing of developmental events.

Explanation:

In evolutionary biology heterochrony refers to change in rate or timing of certain developments in an organism through genetics. This can impact growth, shape, characteristics etc of the organism.

The concept traces its origin to Ernest Heckel. The most common example of heterochrony in humans is the development of brains. In Chimpanzees, the brain growth stops soon after birth while for humans it continues even after birth. This is among several other types of heterochrony present between human and its ancestor and other species.