A second physical characteristic that is usually used to explain Genetics in a simple way is the ear lobe. The structure, considered one of the most evident components of the auricular pavilion, presents changes in the shape, location and dimensions depending on each person, as surgeons Antonio Fuente and Lucas Lesta remember. Perhaps one of its most striking features is the separation of the earlobe from the rest of the face.

Although this characteristic has traditionally been related to the Mendelian inheritance pattern, the fact is that this physical aspect is not determined by a single gene. "We should not use lobe separation to teach basic genetics," McDonald criticizes. A recent research, published in the American Journal of Human Genetics, supports his claims. After studying more than 74,000 individuals, an international team of scientists found that 49 genes seemed to influence whether the earlobe was stuck or separated from the rest of the face.