Cuteness is a type of attractiveness commonly associated with youth and appearance, as well as a scientific concept and analytical model in ethology, first introduced by Konrad Lorenz. Lorenz proposed the concept of baby schema (Kindchenschema), a set of facial and body features that make a creature appear "cute" and activate ("release") in others the motivation to care for it. Cuteness may be ascribed to people as well as things that are regarded as attractive or charming. Juvenile traits Doug Jones, a visiting scholar in anthropology at Cornell University, said that the proportions of facial features change with age due to changes in hard tissue and soft tissue, and Jones said that these "age-related changes" cause juvenile animals to have the "characteristic 'cute' appearance" of proportionately smaller snouts, higher foreheads and larger eyes than their adult counterparts. In terms of hard tissue, Jones said that the neurocranium grows a lot in juveniles while the bones for the nose and the parts of the skull involved in chewing food only reach maximum growth later. In terms of soft tissue, Jones said that the cartilaginous tissues of the ears and nose continue to grow throughout a person's lifetime, starting at age twenty-five the eyebrows descend on the "supraorbital rim" from a position above the supraorbital rim to a position below it, the "lateral aspect of the eyebrows" sags with age, making the eyes appear smaller, and the red part of the lips gets thinner with age due to loss of connective tissue. A study found that the faces of "attractive" Northern Italian Caucasian children have "characteristics of babyness" such as a "larger forehead", a smaller jaw, "a proportionately larger and more prominent maxilla", a wider face, a flatter face and larger "anteroposterior" facial dimensions than the Northern Italian Caucasian children used as a reference. Biological function Konrad Lorenz argued in 1949 that infantile features triggered nurturing responses in adults and that this was an evolutionary adaptation which helped ensure that adults cared for their children, ultimately securing the survival of the species. Some later scientific studies have provided further evidence for Lorenz's theory. For example, it has been shown that human adults react positively to infants who are stereotypically cute. Studies have also shown that responses to cuteness—and to facial attractiveness in general—seem to be similar across and within cultures. In a study conducted by Stephan Hamann of Emory University, he found