Living in the genetic comfort zone
The information encoded in the DNA of an organism is not sufficient to determine the expression pattern of genes. This fact has been known even before the discovery of epigenetics, which refers to external modifications to the DNA that turn genes "on" or "off". These modifications do not change the DNA sequence, but instead, they affect how genes are expressed. Another, less known mechanism called canalization keeps organisms robust despite genetic mutations and environmental stressors. If an organism experiences environmental or genetic perturbations during its development, such as extreme living conditions or genetic mutations, canalization acts as a way of buffering these disturbances. The organism remains stable and can continue to develop without recognizable changes.