Facial feature determinants of perceived infant attractiveness

INFANT BEHAVIORAND DEVELOPMENT2, 329-339 (1979)

Facial Feature Determinants of Perceived Infant Attractiveness* KATHERINE A. HILDEBRANDT SUNY at Buffalo AND

HIRAM E. FITZGERALD Michigan State University

Previous studies of infant facial characteristics that influence adult behavior have used drawings to vary infant facial features. The present study used actual infant faces rather than drawings. Facial feature variations were related to adults' perceptions of infant cuteness using a multiple correlational approach. Ten photographs at each of six age levels were rated for cuteness; then 14 facial features were measured. Resultssuggest that studies using line drawings have varied facial features beyond the range found among actual infants. Nevertheless, facial feature combinations were predictive of perceived cuteness; a cute infant is likely to have short and narrow features, large eyes and pupils, and a large forehead. The potential impact of perceived attractiveness on the organization of adultinfant relationships is discussed.

Ethologists have suggested that certain infant physical characteristics and behaviors elicit approach behavior from human adults (Eibl-Eibesfeldt, 1970; Lorenz, 1943). Particular attention has been paid to facial features which distinguish infants from adults. " B a b y i s h " or infantile facial features include a high and protruding forehead, large eyes placed in the middle of the face, a small nose and mouth, and fat cheeks (Gardner & Wallach, 1965; Hess, 1970). Consistent with ethological theory, several studies have found that both children and adults prefer pictures of infants over pictures of adults (Berman, Cooper, Mansfield, Shields, & Abplanal, 1975; Fullard & Reiling, 1976; Hess & Polt, 1960). In *An earlier version of this report was presented at the annual meeting of the Midwestern Psychological Association, Chicago, Illinois, USA, May, 1977. This research was supported by an NIMH Institutional National Service Award IT32-MH 14622-01 and an NIH Biomedical Science Support Grant. Address requests for reprints to Hiram E. Fitzgerald, Department of Psychology, Michigan State University, East Lansing, MI 48824, USA. 329

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most cases the preference was stronger in women than in men (Berman, 1976; Fullard & Reiling, 1976; Hess & Polt, 1960), although Berman et al. (1975) failed to find sex differences in one college student sample. Experience with infants seems to affect the attraction of men but not women to infants. Cann (1953) found that women preferred baby pictures over adult pictures regardless of their marital or parental status. However, men who were fathers or whose wives were pregnant preferred the baby pictures more often than did other men. A hypothesis derived from ethological theory is that infants whose features are more infantile should be preferred over infants whose features are less infantile (e.g., Sternglanz, Gray, & Murakami, 1977). Two studies have employed a rating technique whereby adults were asked to judge drawings of infant faces which varied systematically in their component features. Brooks and Hochberg (1960) varied eye position and found that a position in the center of the face received higher cuteness ratings than positions higher or lower than the center. In a more detailed study of facial feature variations, Sternglanz et al. (1977) manipulated vertical feature position, eye width, eye height, and iris size one at a time, and eye width and eye height together. College students rated as most attractive those faces which had relatively large eyes and a relatively large forehead. The relationships between attractiveness and facial feature measurements were quadratic rather than linear, so that extremely large eyes and forehead were not considered highly attractive. It is difficult to generalize from studies using stylized drawings of infant faces to facial feature determinants of physical attractiveness in actual infants. For example, the range of variation in feature size used by Sternglanz et al. (1977) was larger than one might expect to find in a sample of real infants; moreover, they did not consider interrelationships among features. The present study was an attempt to relate facial feature variations in actual infants to adults' perceptions of infant attractiveness using a multiple correlational approach. It was hypothesized that more infantile facial features would be associated with higher cuteness ratings.

METHODS

Subjects Cuteness ratings were obtained from 196 college students (98 male, 98 female) enrolled in child psychology classes at Michigan State University. The initial sample size was 477; however, sufficient subjects were randomly discarded to equalize the number of males and females assigned to each presentation order. Subjects were predominantly white and between 18 and 22 years old. Previous research with this population indicated very little variance and no sex difference in the amount of current or previous contact with infants and young children (Hildebrandt, 1976). Most subjects reported having had some contact with in-

FACIAL DETERMINANTS OF INFANT ATTRACTIVENESS

331

fants during their high school years but very little contact with infants since entering college.

Stimuli The stimuli were 60 chromatic photographs of infant faces. There were five male and five female infants at each of the ages of 3, 5, 7, 9, 1 I, and 13 months. A professional photographer took the pictures under controlled conditions when the infant's facial expression was judged to be relatively neutral. The infant's shoulders were covered by a gray cape to remove clothing cues.

Procedure

Cuteness Ratings. Infant photographs were presented in random order via slides for 8 sec each to mixed-sex groups of students. Two random orders were used, one the reverse of the other. Photographs were presented in blocks of ten, with a .5-sec inter-slide interval and an 8-sec blank-slide interval between blocks. Students marked their cuteness ratings on computer answer sheets according to a five-point rating scale. A scale value of 5 was designated "very cute," 4 was "more cute than average," 3 was "average cuteness," 2 was "less cute than average," and 1 was "not very cute." Since there were no differences between the mean ratings given by male and female raters or by raters assigned to each order, cuteness ratings of all subjects were averaged for each infant. Facial Feature Measurement. Each slide was projected' onto a fiat vertical surface with projector distance and orientation 'adjusted so that the face was upright and the distance from the top of the head to the bottom of the chin was 40 cm. Figure 1 illustrates the features measured from each infant face. Measurements were to the nearest mm (or degree, in the case of CHEEKS). The left and right measurements were averaged for the eye and ear features. Nine of the measurements were obtained separately by two experimenters, and interexperimenter reliabilities ranged from .72 to .95 with a mean of .87. Head shape was expressed by two derived measurements: the relative width of the upper part of the head is labeled HEAD HIGH and is equal to HEAD WIDTH 1 divided by HEAD WIDTH 2; the relative width of the lower part of the head is labeled HEAD LOW and is equal to HEADWIDTH3 divided by HEADWIDTH 2. The resulting 14 facial features were used to predict cuteness ratings using the SPSS computer program REGRESSION (Nie, Hull, Jenkins, Steinbrenner, & Bent, 1975). RESULTS Although the major purpose of the cuteness rating procedure was to obtain average cuteness ratings for individual infants, the effects of rater sex, infant sex,

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HILDEBRANDT AND FITZGERALD

°

FOREHEAD

EAR WIDTH

HEAD WIDTH 2 ~

~

DTH EYE ql, HEIGHT

LENGTH ~ e t PUPIL WIDTH L

'

-

•

•

MOUTH WIDTH

Figure 1. Infant facial features measured with head height set to a standard 40 cm. Features were scored individually and combined mathematically to form clusters. The Feature length cluster consisted of nose length and ear height. The Vertical placement cluster combined forehead and mouth height, whereas the Width cluster combined Head width, Head width-2, Nose width, Mouth width, Iris, and Eye width (see text for additional discussion about these variables).

and infant age were also tested using analysis of variance. These results are reported in detail elsewhere (Hildebrandt & Fitzgerald, 1979, experiment 2). In summary, the results were as follows: Female infants received slightly higher cuteness ratings than male infants, and older infants received higher cuteness ratings than younger infants. The highest ratings were given to 9-month-old females and l l-month-old males. Thus, one determinant of cuteness appears to be the developmental level of the infant, with females reaching the peak of

FACIAL DETERMINANTS OF INFANT ATTRACTIVENESS

333

cuteness (as perceived by college students) earlier than males, possibly because of their relative developmental maturity. The 14 facial features used to predict cuteness ratings are listed in Table 1. Sternglanz et ai. (1977) varied the features of their line drawings of faces well beyond the normal range reported here for EYE HEIGHT, EYE WIDTH, and FOREHEAD. For example, we applied our scoring procedure to the line-faces used by Sternglanz et al. (1977). Their forehead variations ranged from 113-273 mm, whereas our forehead measurements with real infants ranged from 201-253 mm (Table 1). Their eye width variations ranged from 30.4-81.3 mm, whereas ours ranged from 39-51 mm. Thus, Sternglanz et al. (1977) may have found quadratic rather than linear relationships between facial feature variations and attractiveness ratings because of this extension beyond the normal range. However, the proportions of their curves which correspond to the natural range of variation are linear. Scatter plots of the facial features considered in the present study as a function of cuteness ratings revealed no obvious quadratic relationship, so a linear model (multiple regression) was used to assess the effects of facial feature variations on the perception of infant cuteness. When all 14 facial features were entered in a regression equation predicting cuteness ratings, a significant multiple correlation (R) of .72 (F(14, 45) = 3.37, p < .001) was obtained. The squared multiple correlation (R z) is .51; thus, about one half of the variation in cuteness ratings can be accounted for by these objectively measurable facial features. The remaining variance probably can be attributed to unmeasured facial features such as hair style or facial expression, and to error of measurement. TABLE 1 Characteristics o f Individual Facial Features

Feature

HEAD LOW HEAD HIGH FOREHEAD EYE HEIGHT EYE WIDTH IRIS PUPIL NOSE LENGTH NOSE. WIDTH MOUTH HEIGHT MOUTH WIDTH CHEEKS EAR HEIGHT EAR WIDTH

~

.81 .99 227 mm 22 mm 45 mm 28 mm 7 mrn 61 mm 61 mm 39rnm 73 mm 92 ° 101 mm 35ram

SD

.05 .05 9.31 2.84 2.66 1.65 .98 2.94 4.33 9.79 6.72 5.22 8.02 8.26

Range

r with Cuteness

.71-.94

-.45

.71-1.08 201-253 13-28 39-51 24--32 5-10 56-69 54-71 19-67 62-92 80-107 81-121 21-80

.11 .25 .07 .03 -.16 .3.5 -.36 -,16 -,17 -.05 .03 -.37 .13

Partial r with Cuteness Controlling far Head Law -.17 .24 .21 .26 .10.29 -.32 -.08 -.21 -.01 .24 -.26 -.05

Partial r with Cuteness Controlling for Age -.32 .15 .24 .20 .16 .04 .30 -.33 -.15 -.17 -.08 .09 -.33 .08

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HILDEBRANDT AND FITZGERALD

The simple correlations between each facial feature and cuteness are reported in Table 1. Interpretations of the independent magnitude and direction of effect of individual variables cannot be based simply on these correlations because of moderate to high intercorrelations among many of the measurements (reported in Table 2). Thus, an attempt was made to f6rm several conceptually and statistically meaningful combinations of measurements that were independent of one another. TABLE 2 Intercorrelations of Individual Facial Feature Measurements

1

2

3

4

5

6

7

8

9

10

11

12

13

14

1 HEAD LOW 2 HEAD HIGH 3 FOREHEAD 4 EYE H E I G H T

.08 - -.08 .27 - . 2 5 - . 0 7 - . 19 m

5 EYE W I D T H 6 IRIS

.40-.09-.25 .52 . 0 4 - . 3 4

7 PUPIL 8 NOSE LENGTH 9 NOSE WIDTH

- . 2 2 .21 .03 .18 . 1 0 - . 1 4 .21 - . 1 4 - . 3 0

.46 - .42 .63 - .19 .08 .18-.08 .11 .57

.10 - .03 .10 - .43 .02 .09 - -

10 MOUTH HEIGHT - . 0 4 - . 1 0 - . 6 4 .07 11 MOUTH W I D T H .10--.08--.12-.16

.02 .44

.03-.18-.04-.12 -.31--.03 .05 .63 .01 - -

12 CHEEKS 13 EAR H E I G H T

.50 .24

.41 . 0 0 - . 3 0 . 2 2 - . 2 7 .29

14 EAR WIDTH

.38-.15 .09-.14 .32-.13-.36 .17

-.31 -.09-.20-.08-.24-.07

.05

.50-.31 .42 .03

.11 - . 1 0

.56 - .26-.01

--

.12-.06-.25-.05

--

To do this, all measurements were first transformed to standard scores. On the basis of an exploratory factor analysis and logical associations between measurements, three relatively independent, additive combinations which incorporated ten of the measurements were derived. The four remaining individual measures were relatively uncorrelated with the groups and with each other. These seven variables are listed in Table 3 with their intercorrelations.

TABLE 3 Intercorrelations Between Variables Used in Second Analysis 1 1 2 3 4 5 6 7

VERTICAL PLACEMENT FEATURE LENGTH WIDTH HEAD HIGH EYE HEIGHT PUPIL EAR WIDTH

2

3

-.17 -.06

.29

--

.21 -.14 .12 -.17

-.02 .21 -.10 .04

.00 .26 -.13 -.35

4

-.07 .21 --.09

5

6

-.19

--

-.08

.05

7

--

FACIAL DETERMINANTS OF INFANT ATTRACTIVENESS

335

The variable labeled VERTICAL PLACEMENT is equal to FOREHEAD minus MOUTH HEIGHT (which largely is a function of how open the mouth is), and reflects the vertical placement of the eyes on the face. NOSE LENGTH and EAR HEIGHT were combined to form a variable labeled FEATURE LENGTH. EYE WIDTH, IRIS SIZE, NOSE WIDTH~ MOUTH WIDTH, and CHEEKS w e r e averaged to form a FEATURE WIDTH variable. However, this variable correlated .42 with HEAD LOW, SO these two variables were combined to form a general WIDTH variable. PUPIL SIZE, EYE HEIGHT, EAR WIDTH, and HEAD HIGH were not strongly correlated with any of these variable combinations or with one another (see Table 3). These seven variables were entered into a forward stepwise multiple regression procedure with cuteness as the predicted variable. The results of this analysis are reported in Table 4. The multiple correlation was significant at each step and reached a maximum of .63 (F(7,52) = 4.85, p < .001). Several measures of the relative influence of each variable are also included in Table 4. If the variables are independent, these measures for a given variable should each provide essentially the same information. In general, this is true. However, it should be noted that the simple correlation between EYE HEIGHT and cuteness is only .07 whereas with FEATURE LENGTH, PUPIL and WIDTH partialed out, the correlation is. 19. This improvement in the correlation implies that the influence of EYE HEIGHT is suppressed by one or all of these preceding variables. Checking back to the initial analysis (Table l), which also entered the 14 individual features into a multiple regression equation one at a time, it can be seen that HEAD LOW (which was the first variable entered) operates as a suppressor variable for a number of features. Once HEAD LOW is partialed out, all the eye measures, forehead measures, and cheeks are positively correlated with cuteness, whereas the nose, ear, and mouth measures are negatively correlated. These are the same characteristics which define " b a b y i s h n e s s . " Additional analyses were performed to assess the effects of infant sex and age on the relationship between facial feature variation and cuteness. A mul-

TABLE 4 Results of Analysis Predicting Cuteness from Seven Variables

Step

Variable Entered

1 2 • 3 4 5 6 7

FEATURELENGTH PUPIL WIDTH EYE HEIGHT VERTICALPLACEMENT EAR WIDTH HEAD HIGH

R

R2 Change

Beta

r with Cuteness

r with Cuteness when Entered in Equatiqn

.45

.21 .09 .04 .02 .02 .01 .00

--.39 .21 -.21 .20 .16 .11 .05

-.45 .35 -.34 .07 .23 .13 .11

-.45

.55 •58 .60 .62 •63 •63

.34 -.23 .19 .18 .13 .06

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HILDEBRANDTAND FITZGERALD

tivariate test of sex differences in the seven variables used in the second analysis revealed no overall effect (F(7,52) = 2.11, p > .05), nor were any of the univariate tests significant. Moreover, if sex is partialed out initially, the variables enter a regression equation predicting cuteness in the same order as before and the same multiple R (.63) is obtained. Thus, the facial feature determinants of cuteness do not seem to differ for male and female infants. The multivariate test of age differences was significant (Roy's Largest Root Criterion = .53 (s = 5, m = I/2, n = 23), p < .01) with the only significant univariate test being that for WIDTH (F(5,54) = 8.29, p < .00001). The correlation between age and WIDTH is --.61, which indicates that older infants have narrower faces and features below the forehead. Older infants also receive higher cuteness ratings. Partialing out age initially reduces the multiple R slightly (to .59) and results in the variables entering the regression equation in the same order as before (and with the same direction of influence), except that WIDTHis entered last. Thus, width of features is less important in predicting the cuteness of infants of the same age than it is in predicting the cuteness of infants of different ages. The partial correlation between WIDTH and cuteness controlling for age is still negative ( - . 19); even within a particular age, infants with narrower features are perceived as cuter. The results of this last analysis suggest that it might be informative to look at the partial correlations between the 14 original variables and cuteness with age controlled. These correlations are shown in Table 1. Cute infants at all ages tend to have large foreheads, large eyes, small features, and narrow faces below the eyes. DISCUSSION These results provide general support for the ethological concept of babyishness as an elicitor of adults' preferential responsivity, in the present case, higher cuteness ratings. Facial features which relate to babyishness significantly predicted cuteness ratings. According to these data, a cute infant is likely to have short and narrow features, large eyes and pupils, and a large forehead. An important point made by this analysis, which is not evident in studies of line drawings, is that feature sizes do not vary independently of one another in actual infants' faces. An infant with a narrow face below the eyes also tends to have narrow features, including narrow eyes. The effect of this common variance among features on cuteness ratings was assessed by combining features into clusters. Thus EYE WIDTH and IRIS were included in the WIDTH cluster, which was negatively correlated with cuteness. Variation in features which was not in common with other features was assessed through the examination of partial correlations. This approach indicated that large eyes and fat cheeks are positively related to cuteness after general feature size and lower head width are taken into account. For example, if two infants have equal lower head sizes and average feature sizes, the one with larger eyes and fatter cheeks would be expected to be

FACIAL DETERMINANTS OF INFANT ATTRACTIVENESS

337

perceived as cuter. Since lower head and feature size change with age, it was not surprising to find that eye size was more predictive of cuteness within ages than across ages. There are limitations to this approach. Only linear, additive effects were considered, and it is possible that more of the variance in cuteness ratings could have been accounted for if curvilinear and interactive effects were included. In addition, a number of obviously important facial features were not included in the analysis. Ethological theory suggests that the curvature of the forehead and cheeks are related to babyishness, but an adequate method of measuring these characteristics from slides was not available. Hair length and style and facial expression were listed as important determinants of infant cuteness in an earlier study (Hildebrandt, 1976), but, again, they are difficult to measure in an objective rather than subjective manner. These features, as well as others, probably account for some of the remaining variance in cuteness ratings. However, there may be a nonadditive "gestalt" factor which influences adults' perceptions of cuteness; that is, the whole of the face may" not be equal to a sum of its parts. Therefore, the inability to perfectly predict cuteness ratings should not be taken as undermining the ethological concept of babyishness as an eliciting stimulus. Nearly all infants have some of the characteristics of babyishness, and as a result they elicit at least minimal positive reactions from adults. For example, when women first look at an infant they smile, regardless of their perception of the infant's perceived attractiveness (Hildebrandt & Fitzgerald, 1978). Sternglanz et al. (1977) offered the possibility of investigating the influence of particular facial feature variations on adult-infant interaction. However, the present analysis suggests that it will be extremely difficult to find infants who differ from one another in only one facial feature. It seems more likely that adult behavior may be influenced by the perceived cuteness of an infant, which is partially a function of the combination of the infant's facial features and partially a function of the infant's behavioral expression. In contrast to the sex difference reported by Sternglanz et al. (1977) none were found in the present study. However, males did tend to use the middle of the rating scale more and the ends of the rating scale less than did females (Hildebrandt & Fitzgerald, 1979). This same tendency may account for Sternglanz et al. 's (1977) finding, since the ratings of males were closer to the center of their scale than were the ratings of females. Although female infants received slightly higher cuteness ratings than male infants, there appear to be no differences in the facial feature determinants of cuteness for the two sexes. If the raters had known the sex of the infants, 'however, they may have used different criteria for judging the cuteness of males and females. Although students can assign sex at above-chance levels to the infants used in the present study, they assign the incorrect sex to about one-fourth of them (Hildebrandt & Fitzgerald, 1977). Thus any sex stereotyping effects on cuteness ratings may be attenuated by the distribution of perceived sex within actual sex groups (Hildebrandt & Fitzgerald, 1979).

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HILDEBRANDT AND FITZGERALD

CONCLUSIONS It is now firmly established that physical attractiveness has a potent influence on adult-adult, adult-child, and child-child social relationships (Berscheid & Walster, 1974). More attractive individuals are thought more highly of and are recipients of more positive behaviors than less attractive individuals. Thus it seems reasonable to expect infant physical appearance to influence caregiver attitudes and behavior. There is some support for this suggestion (Bell, 1974; Blake, Stewart, & Turcan, 1975; Boukydis, 1977; Clifford & Crocker, 1971). Robson and Moss (1970) found that the degree to which an infant was perceived to have physical similarities to other family members was related to maternal feelings of closeness to their infants. Corter, Trehub, Boukydis, Ford, Ceihoffer, and Minde (1976) asked experienced nurses to rate both the physical attractiveness and intellectual prognosis of premature infants and found that they were highly correlated. Whether or not the nurses behaved differently toward infants on the basis of physical attractiveness is not known. However, we have found that both male and female college students and mothers of toddler-age children look longer at photographs of infants they consider cute than they do at pictures of infants they consider less cute (Hildebrandt & Fitzgerald, 1978). In addition, Hildebrandt (1978) found that fathers' ratings of infant physical cuteness were correlated .73 with their ratings of their current relationship with their infants. For mothers, ratings of behavioral cuteness were correlated .76 with '.'present relationship to infant," but ratings of physical cuteness were unrelated to ratings of present relationship. The present results have helped to specify which facial features contribute to adults' perceptions of infant cuteness. Whereas several investigators have suggested that perceived attractiveness influences adult-infant behavioral interactions, at present conclusions regarding the developmental significance of this influence must be advanced with caution.

ACKNOWLEDGMENTS The authors would like to thank the undergraduates who assisted in data collection: Deborah Bruce, Victoria Holmes, and Jane Leavitt. Statistical assistance was I~rovidedby Patrick Ackles and Neil Schmitt.

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Bennan, P. W., Cooper, P., Mansfield, P., Shields, S., & Abplanal, J. Sex differences in attraction to infants--when do they occur? Sex Roles, 1975, /, 311-318. Berscheid, E., & Walster, E. Physical attractiveness. In L. Berkowitz tEd.), Advances in e.~perimen/al social psychology. (Vol. 7). New York: Academic Press, 1974. Blake, A., Stewart, A., & Turcan, D. Parents of babies of very low birthweight: Long-term followup. Parent-b~mt Interaction. Ciha Symposium 33. Amsterdam: Elsevier Publishing Co., 1975. Boukydis, Z. C. F. Infant attractiveness and the infant-caretaker relationship. Paper presented at the International Conference on Love and Attraction, University College of Swansea, Wales, U.K., September 1977. Brooks, V., & Hochberg, J. A psychophysical study of cuteness. Perceptual and Motor Ski/Is, 1960, / / , 205. Cann, M. A. An investigation of a component of parental behavior in humans. Unpublished master's thesis, University of Chicago, 1953. Clifford, E., & Crocker, E. C. Maternal responses: The birth of a normal child as compared to the birth of a child with a cleft. Cleft Palate Journal, 1971,8, 298-306. Corter, C., Trehub, S., Boukydis, C., Ford, L., Celhoffer, L., & Minde, K. Nurses' judgments of the attractiveness of premature infants. Unpublished manuscript, University of Toronto, 1976. EibI-Eibesfeldt, I. Ethology. New York: Holt, Rinehart & Winston, 1970. Fullard, W., & Reiling, A. M. An investigation of Lorenz's "babyness." Child Development, 1976, 47, 1191-1193. Gardner, B. T. & WaHach, L. Shapes of figures identified as a baby's head. Perceptual and Motor Skills, 1965, 20, 135-142. Hess, E. H. Ethology and developmental psychology. In P. Mussen (Ed.), Carmichaers manual of child ps3'chology. (Voi. 1). New York: Wiley, 1970. Hess, E. H., & Poit, J. M. Pupil size as related to interest value of visual stimuli. Science, 1960, 132, 34%350. Hildebrandt, K. A. Adult responses to infant cuteness. Unpublished master's thesis, Michigan State University, East Lansing, MI., 1976. Hildebrandt, K. A. Factors influencing the regulation of gazing, smiling, and vocalizing between parents and their three-month-old infants. Unpublished doctoral dissertation, Michigan State University, East Lansing, MI., 1978. Hildebrandt, K. A., & Fitzgerald, H. E. Gender bias in observers" perceptions of infants" sex: it's a boy most of the time! Perceptual and Motor SkUls, 1977, 45,472-474. Hildebrandt, K. A., & Fitzgerald, H. E. Adults' responses to infants varying in perceived cuteness. Behavioral Processes, 1978, 3, 15%172. Hildebrandt, K. A., & Fitzgerald, H. E. Adults perceptions of infant sex and cuteness. Sex Roles, 1979, 5,471-481. Lorenz, K. Die angeborenen Formen moglicher Erfahrung. Zeitschrififur Tierpsvchologie, 1943, 5, 245-409. Nie, N. H., Hull, C. H., Jenkins, J. G., Steinbrenner, K., & Bent, D. H. Stutisticulpackageft~r the social sciences. (2nd Ed.). New York: McGraw-Hill, 1975. Robson, K. S., & Moss, 14. A. Patterns and determinants of maternal attachment. Journal of Pediatrics, 1970, 77, 976--985. Sternglanz, S. H., Gray, J. L., & Murakami, M. Adul! preferences for infantile facial features: An ethological approach. Anbnal Behavior, 1977, 25, 108- I 15.