Hard inheritance

Hard inheritance is the exact opposite of the term soft inheritance, coined by Ernst Mayr to contrast ideas about inheritance. Hard inheritance states that characteristics of an organism's offspring (passed on through DNA) will not be affected by the actions that the parental organism performs during its lifetime. For example: a medieval blacksmith who uses only his right arm to forge steel will not sire a son with a stronger right arm than left because the blacksmith's actions do not alter his genetic code.

The hard inheritance model excludes ideas of Lamarckism. Inheritance due to usage and non-usage is excluded. Inheritance follows ideas of the synthetic theory of evolution