Heredity
Heredity is the passing of traits from parents to offspring. Before 1900 the common assumption was blending: that a cross produced an average of the two parents. Mendel showed instead that inheritance is particulate, that traits are carried by discrete units that stay intact through a generation and can reappear unchanged in the next one, which is why a trait can skip a generation and return.
Why it matters
Blending inheritance would dilute any new variation away within a few generations, which would leave natural selection with nothing to work on; particulate inheritance is what makes evolution by selection possible.
Also written: inheritance, hereditary
Where it comes up
Read about Heredity on Wikipedia
Sources
- Heredity Wikipedia
- Heredity and Heritability Stanford Encyclopedia of PhilosophyOn what is actually being claimed when a trait is called heritable.
- Gregor Mendel: A Private Scientist Nature Education Scitable
