The view that “people tend to marry people who resemble themselves” has been supported by many previous studies (Griffiths and Kunz, 1973; Zajonc et al., 1987; Hinsz, 1989; Keller et al., 1996; Little et al., 2006; Wong et al., 2018; Tea-makorn and Kosinski, 2020). These studies consistently reported that couples have higher facial resemblance than non-couples.

People also say that people resemble their pets. Coren (1999) reported that women with long hair tend to prefer the lop-eared dogs, while those with the short hairstyles preferred the prick-eared dogs, consistent with non-academic reports that pets look like their owners. Roy and Christenfeld (2004, 2005) have shown that participants could match dogs with their owners, though this result was confined to purebred dogs. They also demonstrated that ownership period and resemblance did not show a significant correlation. Thus, it is presumed that the owners choose dogs that resemble themselves when they start rearing their pets. Payne and Jaffe (2005) have also examined the pet-owner resemblance for wide range of ages and races for both pet owners and participants, using only the faces of the dogs as signals for judges, and showed that participants matched the pets with their owners correctly more than would be expected from random guessing by Monte Carlo simulation. These studies suggest that pets resemble their owners.

Nakajima et al. (2009) used Japanese participants to test dog-owner resemblance. Because the dog owners of Roy and Christenfeld (2004, 2005) were in the US and those of Payne and Jaffe (2005) in Venezuela, the populations of dog owners studied were racially diverse. On the other hand, Japanese people are more homogeneous ethnically, allowing the elimination of ethnic factors. Nakajima et al. (2009) conducted two experiments to show that participants could match dogs with their owners correctly at levels above chance. The results of Nakajima et al. (2009) also suggest that the performance was independent of the gender of the judges, their reported confidence in their decision, their experience keeping dogs as pets, the number of years they kept dogs as pets, the breeds of dogs, and their affection for dogs. In addition, Nakajima (2013) has clarified which part of the face is critical for judgment of dog-owner resemblance. His results suggest that dogs and their owners resemble each other in the eye region.

Can people then match personal belongings, including inanimate objects, to their owners? Alpers and Gerdes (2006) and Stieger and Voracek (2014) examined this with cars. Alpers and Gerdes (2006) used photos of the sides of cars, and Stieger and Voracek (2014) used grayscale photos of the fronts, sides, and backs of cars as stimuli. Alpers and Gerdes (2006) showed that participants were able to match the cars to their owners at above-chance levels. On the other hand, Stieger and Voracek (2014) showed that participants were able to match the owners to the front views of their cars at above-chance levels, but not to the side or back views. In addition, Stieger and Voracek (2014) suggested that people could match dogs to their owners’ cars as well as to their owners. These studies suggest there are some cases in which people can match personal belongings, including inanimate objects, to their owners.

Why were the participants able to match cars to their owners? It may be because the front views of cars resemble human faces. Ichikawa et al. (2011) dealt with face-like objects, for example, electrical outlets, flowers, and houses. Some objects resemble human faces and the headlights of cars look like eyes (Windhager et al., 2012). Thus, matching cars to their owners might involve judging the resemblance between the face-like views of cars and the owners’ face.

In addition to couple, dog-owner, and car-owner resemblance, people sometimes note that the faces of manga characters resemble those of their artists or that the faces of Buddha statues resemble those of their makers, though this may be merely folk psychology or an offhand report just like those of dog-owner resemblances in the past. However, it is possible that people tend to make objects that resemble themselves if they have a tendency to choose such objects. People may reflect their faces in those of statues, portraits, or dolls when there is no specific model, even though they face technical limitations. In this study, we examined whether people tend to make objects that resemble themselves using cloth dolls as stimuli. In Experiment 1, we examined whether the participants could match dolls with their makers—them being able to match, however, does not directly imply doll-maker resemblance. In Experiment 2, we examined whether they could match the two based on facial resemblance.

Does the resemblance between people and objects exist not only in choosing something, but also when making something? For example, the makers may reflect themselves in the faces of drawings, statues, manga characters, and dolls in spite of technical difficulties under conditions of no model. This experiment examined whether people tend to make objects that resemble themselves using a procedure that was used by Nakajima et al. (2009). We used dolls that students made in the classes as stimuli. The students were all amateur doll makers and they made dolls for a puppet show.

Experiment 1 shows that people can match dolls to their makers correctly. In Experiment 2, we examined whether the participants could match the dolls with their makers based on facial resemblance with a resemblance judgment task. Similar performance in both tasks being the same is an indication of the participants thinking that the dolls resemble their makers and matching the former with the latter based on their resemblance.

In this study, we examined whether people make objects that resemble themselves. Experiment 1 showed that the participants could match the dolls with their makers, and Experiment 2 indicated that this matching was based on doll-maker resemblance. Even amateur makers (this study involved college students learning about childcare, who had made dolls for a puppet show for class credit) project themselves into their dolls regardless of whether it is humans or animal dolls. These results suggest that people prefer something that resembles themselves, not only when choosing objects but also when making them.

These results raise two questions. First, where is the resemblance evident. Second, why do the dolls resemble their makers? Nakajima (2013) demonstrated that dogs and their owners resemble each other in the eye region. However, the eyes of dolls are often simpler than those of dogs and humans, and it is not clear if they resemble them. This requires further study.

Why do they resemble each other? In the case of pets, while Roy and Christenfeld (2004, 2005) revealed that people select pets that resemble themselves, they do not provide the psychological mechanisms behind such selection. However, some accounts have been proposed by Hinsz (1989) and Payne and Jaffe (2005). In our study, we considered the mere exposure effect and the algorithm “self seeks like.”

Mere repeated exposure to a stimulus produces a more positive attitude toward it (Zajonc, 1968; Hinsz, 1989). Repeated exposure enhances attitudes toward a wide variety of stimuli, including the human face (Moreland and Zajonc, 1982; Hinsz, 1989). People are likely to be more attracted to faces they have seen most frequently (Moreland and Zajonc, 1982)—that is, their own face (through mirror exposure). Thus, mere repeated exposure would suggest that people prefer faces that resemble their own (Mita et al., 1977). It is through this process that they choose a pet or a partner whose face resembles their own. In addition, people make doll faces that resemble their own because those faces are more attractive.

“Self seeks like” is an evolutionarily shaped, narcissistic psychological algorithm and seems to be an innate behavioral trait in people—it characterizes assortative mating that seems to be widely practiced in nature (Alvarez and Jaffe, 2004; Payne and Jaffe, 2005). Assortative mating increases the probability of finding a genetically similar partner (Payne and Jaffe, 2005). If facial features are largely determined by genetic factors, we should detect assortative mating based on facial visual cues (Alvarez and Jaffe, 2004). Interestingly, it seems “self seeks like” is applied in situations where no reproductive purpose is involved (Alvarez and Jaffe, 2004)—Payne and Jaffe (2005) have suggested that people choose their pets by applying this algorithm.

It is not clear under what situations these algorithms would work, except when selecting objects. This study demonstrated that these algorithms work when creating objects. Unfortunately, we cannot conclude which mechanism is appropriate. However, it may be improbable that “self seeks like” works at creating objects because the algorithm is believed to be based on assortative mating, though it may be possible that the algorithm works at selecting objects.

It is often the case that we cannot make objects as we intend. For example, it is not easy for most people with big eyes to make dolls with big eyes because it requires skill or techniques, while it is easier for them to select dogs with big eyes. Nevertheless, our experiments demonstrated that even amateur doll makers, who made dolls for class credit, projected themselves into dolls unconsciously and made dolls that resembled themselves. This suggests that the mechanisms that people prefer objects that resemble themselves are powerful. This may be because the mechanism works repeatedly to make corrections and we have enough time to project ourselves when making objects over time.

This study demonstrated that people project themselves not only when selecting but also making something. If this is the case, statues of humans, including Buddha statues, and manga characters and their makers should show resemblances. This awaits further study, but the makers’ faces might be inferred from statues made some hundreds of years ago or from manga characters.

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.

The studies involving human participants were reviewed and approved by Ethics Committee of Hakodate Junior College. The patients/participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.

MU and MK conceived, designed, and performed the experiments at Hakodate Junior College and Aoyama Gakuin Women’s Junior College. MK analyzed the data. MU wrote up the study. All authors contributed to the article and approved the submitted version.

This work was supported by JSPS KAKENHI Grant Number JP16K12516 to MK and MU. Open access publication fees were received from Aoyama Gakuin University.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.