- For the scientific journal Heredity see Heredity (journal)
Heredity (the adjective is hereditary) is the transfer of characters from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws).
In biology, heredity refers to the transference of biological characteristics from a parent organism to offspring, and is practically a homonym for genetics, as genes are now recognized as the carriers of biological information. In humans, defining which characteristics of a final person are due to heredity and which are due to environmental influences is often a site of controversy (the nature versus nurture debate), especially regarding intelligence and race.
It was apparent to ancient humans that offspring resembled their parents. For example, Genesis 30_46 tells how Jacob and Laban split their sheep into white and speckled varities so they could distinguish the two to ensure none was later stolen. The mechanism of heredity was not clear however.
Various hereditary mechanisms were proposed without being properly tested. These include blending inheritance and the inheritance of acquired characteristics.
The inheritance of acquired characteristics was part of Lamarckism and later Lysenkoism.
Charles Darwin proposed a theory of evolution in 1859 and one of its major problems was a lack of coherent hereditary mechanism. Darwin believed in a mix of blending inheritance and the inheritance of acquired characteristics. Blending inheritance would lead to uniformity across populations in only a few generations and thus would remove variation from a population on which natural selection could act. This led to Darwin adopting some Lamarckian ideas in later editions of The Origin.
The idea of particulate inheritance of genes can be attributed to the Austrian monk Gregor Mendel who published on pea plants in 1865. However, his work was not widely known and was only rediscovered in 1901.
The inheritance of acquired characteristics was shown to have little basis when August Weissman cut the tails off mice to find that their offspring. This, combined with better genetic knowledge led to the idea being dropped.
The social institution called inheritance. One's bloodline is one's familial ancestry. See also meme.