‘Human earlobes may be free or detached (hanging free from the head) or attached (joined to the head). Whether the earlobe is free or attached is a classic example of a simple genetic dominance relationship; freely hanging earlobes are the dominant allele and attached earlobes are recessive. Therefore, a person whose genes contain one allele for free earlobes and one for attached lobes will display the freely hanging lobe trait. It is a common misconception that this implies a precise 3-to-1 ratio between free and attached lobes in the human population. Such a ratio would require that the allele frequency for free lobes were precisely 50%, which there is no reason to assume.’
– Lai L.Y. 1946. Observations on Ear Lobe Types (Acta Genetica et Statistica Medica) Basel, Switzerland: Karger (1966) p. ?
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