'Genes' refers to hereditary units of information made up of DNA and are found on chromosomes and can exist in alternative forms called alleles (http:/ /biology.about.com /library/glossary/bldefgenes.htm).'Environment' according to the American Heritage Dictionary of the English Language, fourth edition states: "[The environment is] the totality of the circumstances surrounding an organism or group of organisms, in particular: the complex of social and cultural conditions that influence the nature of an individual or a community”. that contribute. The first influence derives from the genetic structure he inherits from his parents, the second derives from the collective experiences he derives from his daily social interaction with the surrounding environment. The first section of the essay will present an overview of the influences of genetic and environmental factors on child development. This section will illustrate the different aspects of child development that are best understood within an epigenetic framework and how theories of child development “miss” without considering gene-environment interactions. The second section will discuss the interaction between genes and environment and their significant contributions to child development, such as intelligence and the acquisition of "cultural tools". In this section we will examine the concept of individual differences, the importance of learning about one's existence, and how biological processes influence individuality through the study of the transactional model. Evolutionary theory is a useful approach to understanding what aspects of a child develop throughout their life and how they occur. Evolutionary theorists believed that development simply reproduces what was present in the previous generation and will remain unchanged forever. Human beings, however, change in many ways. They develop physical and psychological characteristics, each with its own set of causes and development. Our physical appearance and gender are the result of genetic influence. Females have two "X" chromosomes while males have one "Y" and one "X" chromosome. Differences in physical development due to chromosomes