and lifestyle (makeup, facial hair, glasses, angle of pictures taken of self, etc.). For more information of this sexual orientation issue in general, see gaydar. In 2020, a study on the use of consumer facial images for marketing research purposes concluded that deep learning on facial images can extract a variety of personal information relevant to marketers and so users' facial images could become a basis for ad targeting on Tinder and Facebook. According to the study, while most of facial images' predictive power is attributable to basic demographics (age, gender, race) extracted from the face, image artifacts, observable facial characteristics, and other image features extracted by deep learning all contribute to prediction quality beyond demographics. Three Theoretical Pathways linking Facial Appearance with Psychological Traits Kosinski (2023) argues that there are three theoretical pathways that could link facial appearance with psychological traits. The three pathways are: First, facial appearance can shape psychological traits (face→mind pathway). The self-fulfilling prophecy effect postulates that people perceived as having a particular attribute are treated accordingly; internalize such attributions; and, over time, may engage in behaviors consistent with others’ perceptions. For example, people with larger jaws are perceived as more socially dominant; and thus, with time, may become more so 2011). Moreover, face-based perceptions influence consequential outcomes such as the length of prison sentences, occupational success, educational attainments, the chances of winning an election, income, and status. Second, there are latent factors shaping both psychological traits and facial appearance (face←factor→mind pathway). Those include socioeconomic status, environmental and developmental conditions, hormones, genes, etc. Twin studies, for example, have found that genes are responsible for over 50% of the variation in both facial features and political orientation. Similarly, prenatal and postnatal testosterone affect jaw shape and are linked—to a small degree—with character traits closely related to political orientation, such as conscientiousness. Furthermore, prenatal exposure to nicotine and alcohol affects facial morphology and cognitive ability, which is associated with political orientation Third, psychological traits can shape facial appearance (mind→face pathway). While we tend to think of facial features as relatively fixed, they are shaped by factors such as facial care, diet, substance use, physical health, injuries, exposure to sunlight, harsh environmental conditions, or emotional states. Exposure to such face-altering factors, in turn, is associated with psychological traits. Liberals, for example, tend to smile more intensely and genuinely—which, over time, leaves traces in wrinkle patternsConservatives tend to be more