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Sex Differences in Romantic Kissing among College Students: An Evolutionary Perspective

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  • Pennsylvania State University Harrisburg

Abstract and Figures

This study provides a descriptive account of kissing behavior in a large sample of undergraduate college students and considers kissing in the context of both short-term and long-term mating relationships. Kissing was examined as a mate assessment device, a means of promoting pair bonds, and a means of inducing sexual arousal and receptivity. A total 1,041 college students completed one of three questionnaires measuring kissing preferences, attitudes, styles, and behaviors. Results showed that females place more importance on kissing as a mate assessment device and as a means of initiating, maintaining, and monitoring the current status of their relationship with a long-term partner. In contrast, males place less importance on kissing, especially with short-term partners, and appear to use kissing to increase the likelihood of having sex. The results suggest that kissing may play an important role as an adaptive courtship/mating ritual. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Evolutionary Psychology
www.epjournal.net – 2007. 5(3): 612-631
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Original Article
Sex Differences in Romantic Kissing Among College Students: An
Evolutionary Perspective
Susan M. Hughes, Department of Psychology, Albright College, Reading, PA 19612, USA Email:
shughes@alb.edu (Corresponding author)
Marissa A. Harrison, Department of Social Sciences and Human Services, Borough of Manhattan Community
College, The City University of New York, New York, NY, 10007, USA
Gordon G. Gallup, Jr., Department of Psychology, University at Albany, State University of New York,
Albany, NY 12222, USA
Abstract: This study provides a descriptive account of kissing behavior in a large sample
of undergraduate college students and considers kissing in the context of both short-term
and long-term mating relationships. Kissing was examined as a mate assessment device, a
means of promoting pair bonds, and a means of inducing sexual arousal and receptivity. A
total 1,041 college students completed one of three questionnaires measuring kissing
preferences, attitudes, styles, and behaviors. Results showed that females place more
importance on kissing as a mate assessment device and as a means of initiating,
maintaining, and monitoring the current status of their relationship with a long-term
partner. In contrast, males place less importance on kissing, especially with short-term
partners, and appear to use kissing to increase the likelihood of having sex. The results
suggest that kissing may play an important role as an adaptive courtship/mating ritual.
Keywords: kissing, sex differences, sexual behavior, pair bonding, mate assessment
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Introduction
Kissing between sexual and/or romantic partners occurs in over 90 percent of
human cultures (Eibl-Eibesfeldt, 1970; Fisher, 1992). Even in cultures where kissing is
nonexistent or condemned, sex partners may blow in each other’s faces, lick, suck, or rub
their partner’s face prior to intercourse (Ford and Beach, 1951). Some non-human animals
appear to engage in kissing-like behaviors, as well (Geer, Heiman, and Leitenberg, 1984).
For instance, de Waal (2000) claims that bonobos regularly engage in bouts of deep tongue
kissing. Although kissing is a widespread practice among humans, few investigators have
Kissing
attempted to assess the adaptive significance of kissing behavior. In the present study, we
investigated sex differences in kissing among college students in light of some prevailing
theories about why kissing may be adaptive. We also considered kissing behavior in the
context of both long-term and short-term mating.
Hypothesis 1: Kissing as a Mate Assessment Device
Some theorists suggest that kissing can be an investigatory process that places
individuals in close proximity to each other in order to smell, taste, and assess other
features that may contribute to making mate assessments (Fisher, 1983). Studies have
shown that the taste and the breath of an individual's mouth can be indicative of underlying
health problems (Durham, Malloy, and Hodges, 1993; Hoshi, Yamano, Mitsunaga,
Shimizu, Kagawa, Ogiuchi, 2002; Rosenberg, 2002; Service, 1998). In addition to
information provided by olfactory cues during kissing, there may be a transfer of sebum
from the suction of the skin surface around the mouth and the surfaces of the buccal, oral,
and gingival mucosae inside the mouth. The exchange of sebum during kissing could
mediate pheromonal and hormonal information (Montagna and Parakkal, 1974; Nicholson,
1984).
We hypothesize that females will place a greater importance on kissing for making
assessments about the health and quality of a potential mate, since females tend to practice
more discriminative mating due to their limited reproductive potential and greater parental
investment (Trivers, 1972). In addition, females have a heightened sense of olfactory and
taste detection compared to males and this greater chemosensory acuity becomes even
more pronounced during ovulation (Doty, Shaman, Applebaum, Giberson, Siksorski, and
Rosenberg, 1984; Pause, Sojka, Bernfried, Krauel, Fehm-Wolfsdorf, and Ferstl, 1996).
Such detection enhancement may put females in a better position to use chemosensory cues
during kissing to assess potential mates.
Men, being the less investing sex, are expected to be less discriminating when
seeking short-term mates (Symons, 1979). However, features that signal a female’s fertility
are often important to males when making assessments of both short- or long-term mates
(Symons, 1979). We suspect that certain physical features, such as a female’s body weight,
may influence a male’s decision to kiss a partner. In addition, both breath odor and saliva
may provide cues to a woman’s fertility. For instance, the rise in estrogen that occurs near
the onset of menstruation triggers the shedding of body cells, including cells present in
mouth, creating a condition that is ideal for bacterial growth which may cause a woman to
have unpleasant breath near her menstrual period (McCann and Bonci, 2001). It is also
thought that changes in estrogens may lead to an increase in sulfur compounds in the mouth
that can cause unpleasant odors (Tonzetich, Preti, and Huggins, 1978). Furthermore,
females produce other distinctive, yet odorless molecules in saliva while ovulating
(Fullagar, 2003) that might be detected by males during kissing.
However, given that males are less sensitive to chemosensory cues, making such
assessments of a female’s fertility by means of kissing may be more difficult, and we
suggest that males may require greater salivary exchange to facilitate assessments of female
fertility and, for that reason, prefer wetter, open mouth, tongue kisses.
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Kissing
Hypothesis 2: Kissing Induces Bonding
Nicholson (1984) contends that kissing may be a mechanism by which pheromones
and sebum are exchanged to induce bonding. Accepting a kiss may be indicative of one’s
commitment to that person (Zahavi and Zahavi, 1997, p. 218) and a sign that one is willing
to accept the risk of contracting an illness. Kissing can even trigger fatal allergic responses
to food (Hallett, Haapanen, and Teuber, 2002). In addition, kissing may be used by both
sexes as a reconciliation gesture and a way to reestablish a bond after an argument or a
fight. Furthermore, activities causing sexual excitement, such as kissing, may increase
levels of oxytocin in both sexes, which has been shown to play a role in interpersonal
bonding (Carter, 1992).
Gulledge, Gulledge, and Stahmann (2003) found that kissing on the lips was rated
by both college men and women as being more intimate than “cuddling,” “holding hands,”
“hugging,” “caressing,” “stroking,” “massages,” “backrubs,” and “kissing on the face.” In
addition, the amount of reported kissing between partners is directly proportional to
relationship satisfaction (Gulledge, et al., 2003), and both sexes rate kissing as one of the
most highly romantic acts a couple can engage in (Tucker, Marvin, and Vivian, 1991). If
kissing serves to create a bond between partners, one would not expect to see kissing in
situations where bonding is not wanted, such as in commercial sex or casual sexual
encounters. For instance, prostitutes often refuse to kiss clientele, because kissing reflects a
“genuine desire and love for the other person” (Brewis and Linstead, 2000, p. 90) and their
refusal to kiss clients is thought to be an emotional distancing technique (Arnold and
Barling, 2003, p.15).
We hypothesize that kissing functions to promote, maintain, and assess the status of
bonding by both sexes, especially in long-term relationships. On the other hand, when it
comes to short-term mating, men may avoid women who demand serious commitments or
investments before consenting to sex (Buss and Schmitt, 1993). Therefore, men may place
less importance on kissing with short-term mates to avoid creating a bond. The benefits
afforded to females who pursue short-term mating strategies are different than those for
males. Reasons why females engage in short-term mating may include gaining resources
(Smith, 1984; Symons, 1979), achieving genetic diversity among their children (Smith,
1984), mate switching (Smith, 1984; Symons, 1979), or current mate manipulation
(Symons, 1979). In these instances, creating a bond with a short-term mate may be more
likely, so the idea of kissing and bonding in a short-term relationship could be more
important to females.
Hypothesis 3: Kissing Increases Sexual Arousal and Receptivity
Kissing can also be viewed as an activity that increases sexual arousal and
receptivity. There is evidence that males, in particular, use kissing as an attempt to
“seduce” romantic partners and kissing may be used by men as a strategy to gain sexual
access to females. Studies of date rape suggest that men feel more entitled to force sexual
intercourse if they have been kissing their partner (Abbey, McAuslan, Zawacki, Clinton,
and Buck, 2001, p. 787; Goodchilds and Zellman, 1984; Koss, 1988). Muehlenhard and
Cook (1988) found that women were more likely than men to have been kissed against
their wishes. Moreover, Christopher (1988) reported that 57% of college-aged women had
been pressured into kissing by physical attempts, verbal coercing or threats, or actual force
in an attempt to make them more sexually receptive. Forced kissing is also reported in other
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Kissing
cultures. In a sample of university students in India, 33% of women and 27% of men
acknowledged being forced to kiss by a romantic partner (Waldner, Vaden-Goad, and
Sikka, 1999). Likewise, in a study of Chinese college students, 20.3% of the women
reported having been in a dating situation where they had been kissed against their will, and
8.2% of the men reported that they had kissed a woman against her will (So-Kum Tang,
Critelli, and Porter, 1995). One speculative possibility is that men may unwittingly use
kissing to introduce substances such as hormones or proteins into women’s mouths, thereby
manipulating their mating psychology, and perhaps making them more likely to have sex.
It is also possible that males may perceive a greater wetness or salivary exchange during
kissing as an index of the female’s sexual arousal/ receptivity, similar to the act of sexual
intercourse.
We hypothesize that in long-term relationships, both sexes will place equal
importance on kissing, especially with saliva exchange, to facilitate sexual arousal and
receptivity. On the other hand, when it comes to short-term relations, females may be less
inclined to kiss and exchange saliva if they choose not to have intercourse. We also
hypothesize that both sexes may be more jealous if they know their partner kissed another
person with tongue contact, since this style of kissing is associated with the intent to arouse
and could therefore lead to sexual infidelity.
The present study provides a descriptive account of kissing behavior by measuring
attitudes, preferences, and sex differences among a large sample of college students, and
considers kissing within the context of both short-term and long-term mating situations.
Specifically, we examined several features of kissing behavior that include different kissing
styles (i.e., open mouth kisses, wetness, tongue contact), kissing and sexual behavior,
bonding and relationship status, and the attractiveness and physical traits of kissing
partners.
Materials and Methods
A series of three studies approved by the local Institutional Review Board were
conducted using anonymous questionnaires administered to students enrolled in
psychology courses at the University at Albany, State University of New York. A total of
1,041 respondents completed one of three anonymous questionnaires in a classroom
setting. In order to assure that responses were based, in part, on first-hand experience,
participants who indicated that they had never romantically kissed another person were
excluded for the analyses. Since we were examining opposite sex relations as it relates to
mating strategies, we only included those who indicated a preference for kissing “only” or
“mostly” members of the opposite sex.
Study 1
Method
Respondents were asked to report their attitudes and experiences regarding several
facets of kissing behavior, including short- versus long-term partner kissing, tongue
kissing, and kissing with respect to sexual behavior. The first questionnaire was
administered to 501 (175 males and 326 females) undergraduate students. Of the
participants, 93.6% fell in the range of 18-24 years of age, while the remaining 6.4% fell in
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Kissing
the “25 and above” category. Two participants who reported having never kissed were
excluded from the study and only those who had a preference for kissing “only” or
“mostly” members of the opposite sex were included for the analyses, yielding a sample of
470 (162 males and 308 females). Of those who reported having experience with romantic
kissing, 10% indicated having kissed 1-2 partners, 15% 3-5 partners, 23% 6-10 partners,
27% 11-20 partners, and 25% kissed 21 or more partners. There were no sex differences in
terms of number of kissing partners, t(468) = -0.48, p = 63, ns. Males (M = 14.1, SD =
2.4) and females (M = 14.2, SD = 2.0) also did not differ with regards to the age of their
first romantic kiss, t(453) = -0.62, p = .54, ns. Fifty-three percent of the respondents
indicated that they were currently in a committed, long-term relationship.
Results
Breath and Taste
Respondents were asked to rate the importance of a person’s breath when deciding
to kiss or continue to kiss someone based on a five point Likert scale (0 = not at all
important, 1 = slightly, 2 = somewhat, 3 = very, and 4 = extremely important). Females (M
= 3.09, SD = 0.82) rated a person’s breath as more important when deciding to kiss or
continue to kiss someone than did males (M = 2.88, SD = 0.88), t(465) = -2.56, p = .011,
significant using a Bonferroni correction, η
2
= .014. Similarly, females (M = 3.00, SD =
0.87) rated the taste of someone's mouth as more important when deciding to continue to
kiss someone than did males (M = 2.67, SD = 0.87), t(465) = -3.79, p = .000, using a
Bonferroni correction, η
2
= .030.
Kissing and Sexual Behavior
Participants were asked if they would have sex with someone without kissing. As
shown in Figure 1, whereas over half of the males (52.8%) indicated that they would have
sex without kissing, only about one in seven females would consider having sex with
someone without kissing them first (14.6%), [
Χ
2
(1, N = 446) = 72.38, p < .000].
Respondents answered questions regarding the importance of kissing before,
during, and after sexual intercourse with a committed, long-term partner and a casual,
short-term partner based on a five-point Likert scale (0 = not at all important, 1 = slightly,
2 = somewhat, 3 = very and 4 = extremely important). A 2 X 2 X 3 mixed design ANOVA
was conducted with sex of respondent (male/female) as the between-subject factor, and
relationship status (long-or short-term partner) and time surrounding sex (before sex/during
sex/after sex) as the within-subject factors. There was a main effect for sex of respondent,
with females (M = 2.47, SE = 0.05) rating kissing as more important than males across all
situations (M = 2.04, SE = 0.06), F(1,337) = 30.83, p =.000, partial η
2
= .084. There was a
main effect for relationship status, with kissing rated as more important across all situations
with committed, long-term partners (M = 2.75, SE = 0.04) than with short-term partners (M
= 1.76, SE = 0.05), F(1,337) = 300.77, p = .000, partial η
2
= .472. There was also a main
effect for the importance of kissing with respect to time surrounding intercourse (before sex
M = 2.62, SE = 0.04, during sex M = 2.20, SE = 0.05, and after sex M = 1.94, SE = 0.05),
F(2,337) = 121.27, p =.000, partial η
2
= .265. Furthermore, as seen in Figure 2, there was
an interaction between relationship status and time of kissing with respect to intercourse,
F(2,337) = 38.84, p =.000, partial η
2
= .103.
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Kissing
Figure 1. Differences in the willingness to have sex without kissing for males (n = 144) and females (n =
302).
0
20
40
60
80
100
Yes No
Would you have sex with someone without
kissing?
Percent
Males
Females
Participants were asked how likely kissing would lead to sex when involved with a
short- or long-term partner, with response choices scaled as 0 = never, 1 = sometimes, and 2
= always. A 2 (sex of respondent) X 2 (relationship status) mixed design ANOVA
revealed a main effect for sex of respondent, with males (M = 1.02, SE = 0.03), feeling that
kissing should lead to sex more often than females (M = 0.78, SE = 0.02), F(1, 454) =
45.61, p =.000, partial η
2
= .091. There was also a main effect for relationship status;
respondents thought that kissing should lead to sex more often with a long-term partner (M
= 1.03, SE = 0.02), than with a short-term partner (M = 0.80, SE = 0.02), F(1, 454) =
102.11, p =.000, partial η
2
= .184. In addition, there was a significant interaction between
sex of respondent and relationship status F(1, 454) = 41.19, p =.000, partial η
2
= .083.
Females thought kissing should lead to sex more with a long-term partner (M = 0.98, SD =
0.33) than with a short-term partner (M = 0.56, SD = 0.55), whereas males felt that kissing
should lead to sex to the same degree with both a long-term (M =1.07, SD = 0.34) and a
short-term partner (M = 0.97, SD = 0.50).
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Kissing
Figure 2. The importance of kissing before, during, and after sex with a long-term partner or short-term
partner rated on a five-point Likert scale (1 = not at all important, 1 = slightly 2 = somewhat, 3 = very and 4 =
extremely important).
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Before
Sex
During
Sex
After Sex
Kissing In Relation to Sex
Mean Importance Ratings
Males
Females
Bonding and Relationships
Participants were asked to rate the importance of kissing at the beginning and
during the latter parts of a relationship using a five-point Likert scale (0 = not at all
important, 4 = extremely important). A 2 (sex of respondent) X 2 (relationship duration)
mixed design ANOVA was conducted that showed a main effect for sex of respondent,
where females (M = 2.78, SE = 0.04), rated kissing as being overall more important than
did males (M = 2.45, SE = 0.06), F(1, 455) = 18.89, p =.000, partial η
2
= .040. There was a
main effect for relationship duration, where respondents thought that kissing during the
beginning of a relationship (M = 2.67, SE = 0.05) was more important than during the latter
parts of the relationship (M = 2.56, SE = 0.05), F (1,455) = 4.94, p = .027, partial η
2
= .011.
There was also a significant interaction between sex of respondent and relationship
duration, F(1,455) = 15.45, p = .000, partial η
2
= .011. As shown in Figure 3, for males, the
importance of kissing decreased as the relationship progresses over time (beginning M =
2.60, SD = 0.89 and latter M = 2.30, SD = 1.00), t(151) = 3.50, p = .001, whereas the
importance of kissing remained relatively constant throughout the relationship for females
(beginning M = 2.74, SD = 0.90 and latter M = 2.82, SD = 0.91), t(304) = -1.54, p = .124,
ns.
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Kissing
Figure 3. Based on a five-point Likert scale (0 = not at all important, 1 = slightly 2 = somewhat, 3 = very and
4 = extremely important), ratings of kissing importance during the beginning of the relationship as compared
to latter phases for males (n = 153) and females (n = 307).
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Beginning Latter
Relationship Duration
Mean Importance Rating for Kissing
Males
Females
When it comes to kissing as a form of reconciliation, significantly more males
(70.1%) thought kissing a romantic partner could end a fight than did females (58.0%), [
Χ
2
(1, N = 477) = 5.75, p = .016]. However, the majority of males (69%) and females (67%)
felt that just because someone was a good kisser would not be a reason to start a
relationship [
Χ
2
(1, N = 429) = 0.13, p = .716, ns].
Salivary Exchange
Respondents were asked how “wet” they preferred their kisses when kissing a
short- or long-term partner, where responses were scaled as 0 = totally dry, 1 = slightly
moist, 2 = somewhat wet, 3 = very wet, and 4 = extremely wet. Based on a 2 (sex of
respondent) X 2 (relationship status) ANOVA, there was a main effect for sex of
respondent, with males (M = 1.83, SE = 0.05) preferring overall wetter kisses than females
(M = 1.38, SE = 0.03), F(1, 418) = 65.76, p =.000, partial η
2
= .136. There was a main
effect for relationship status, where respondents preferred wetter kisses when kissing a
long-term partner (M = 1.69, SE = 0.03) than a short-term partner (M = 1.52, SE = 0.03),
F(1, 418) = 30.26, p =.000, partial η
2
= .067. There was also a significant interaction
between sex of respondent and relationship status F(1, 418) = 5.56, p =.019, partial η
2
=
.013. Males preferred wet kisses with both long-term (M = 1.88, SD = 0.63) and short term
partners (M = 1.79, SD = 0.66) t(139) = 1.91, p = .060, whereas females preferred wet
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Kissing
kisses with long-term partners more (M = 1.50, SD = 0.57) than with short-term partners
(M = 1.26 SD = 0.62), t(279) = 6.82, p = .000.
Participants were also asked to rate how much tongue contact they thought should
be involved in a romantic kiss when kissing a long-term as opposed to a short-term partner.
Responses ranged on a five point Likert scale from 0 = not at all involved to 4 = extremely
involved. There was a main effect for sex of respondent, with males (M = 2.22, SE = 0.08)
preferring more tongue contact than females (M = 2.00, SE = 0.06), F(1, 425) = 4.44, p
=.036, partial η
2
= .010. There was a main effect for relationship status, with respondents
preferring more tongue contact with long-term (M = 2.35, SE = 0.08), than short-term
partners (M = 1.86, SE = 0.05), F(1, 425) = 32.56, p =.000, partial η
2
= .071. There was
also a significant interaction between sex of respondent and relationship status, F(1, 425) =
6.61, p = .010, partial η
2
= .015. Whereas both males (M = 2.35, SD = 0.72) and females (M
= 2.36, SD = 1.93) preferred more tongue contact with long-term partners, t(444) = .002, p
= .998, ns, when it came to tongue contact with short-term partners, males (M = 2.08, SD =
0.81) preferred more tongue contact than females (M = 1.64 SD = 0.90), t(428) = 4.85, p =
.000.
There were no sex differences in preferences for open or closed mouth kisses with
long-term partners; 65.6% of males and 64.7% of females preferred open mouth kisses
when kissing a long-term partner, [
Χ
2
(2, N = 446) = .048, p = .976, ns]. However, when
kissing a short-term partner, more males (55.6%) preferred open mouth kisses than females
(36.8%), [
Χ
2
(2, N = 411) = 21.70, p = .000].
Study 2
Method
The second study was undertaken as an elaboration and partial replication of the
first. The second questionnaire was administered to an additional 273 undergraduate
students (56 males and 217 females). Most (93.4%) of the participants were within the 18-
24 age-range, with the remainder being above age 25. Three participants who reported
never kissing were excluded from analyses and only those who indicated a preference for
kissing “only” or “mostly” the opposite sex were included, yielding a sample of 257 (49
males and 208 females). Of the participants who reported kissing, 11% had kissed 1-2
partners, 21% 3-5 partners, 25% 6-10 partners, 23% 11-20 partners, and 20% kissed 21 or
more partners. There was no sex differences with regards to how many different partners
respondents had kissed t(254) = -0.69, p .494, ns. Sixty percent indicated that they were
currently in a committed, romantic relationship.
Results
Kissing and Sexual Behavior
Participants were asked how likely they would be to have sex without kissing in
order to clarify the distinction between a committed long-term relationship versus a short-
term casual sexual encounter. Responses were recorded on an interval scale from 0 = never
to 4 = always. A 2 (sex of respondent) X 2 (relationship status) ANOVA was conducted.
There was a main effect for relationship status, with respondents indicating that they would
be more likely to have sex with a short-term partner (M = 1.24, SE = 0.09) without kissing
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than with a long-term partner (M = 0.80, SE = 0.08), F(1, 197) = 28.51, p =.000, partial η
2
= .126. There was also a significant interaction between sex of respondent and relationship
status F(1, 197) = 10.94, p =.001, partial η
2
= .053. Males were more likely to have sex
without kissing a short-term partner (M = 1.51, SD = 1.14) than were females (M = 0.97,
SD = 0.98), t(204) = 2.57, p = .011, whereas the likelihood of having sex without kissing a
long-term partner was similar for males (M = 0.79, SD = 1.00) and females (M = 0.80, SD
= 0.84), t(237) = 0.24, p = .811, ns.
Questions about whether kissing should lead to sex when involved with a short-
term or long-term partner were asked again to extend the frequency choices to a five-point
Likert scale (0 = never to 4 = always). Replicating the findings on the first questionnaire, a
2 (sex of respondent) X 2 (relationship status) mixed design ANOVA showed a main effect
for sex of respondent; males (M = 2.30, SE = 0.11) thought kissing should lead to sex more
often than females (M = 1.66, SE = 0.06), F(1, 215) = 25.57, p =.000, partial η
2
= .106.
There was also a main effect of relationship status, where respondents thought kissing
should lead to sex more often with a long-term (M = 2.14, SE = 0.07), than with a short-
term partner (M = 1.83, SE = 0.08), F(1, 215) = 13.11, p =.000, partial η
2
= .057. There was
a significant interaction between sex of respondent and relationship status F(1, 215) =
11.28, p =.001, partial η
2
= .050. Although males thought kissing should lead to sex with a
long-term partner (M = 2.31, SD = 0.87) as much as with a short-term partner (M = 2.29,
SD = 0.99), t(41) = 0.14, p =.891, ns, females thought kissing should lead to sex more
often with a long-term (M = 1.97, SD = 0.84) than a short-term partner (M = 1.34, SD =
0.96), t(174) = 8.05, p = .000.
We also asked which sex generally initiates kissing before and after sex. Response
options were presented on a five-point categorical scale where 0 = only men, 1 = mostly
men, 2 = men and women equally, 3 = mostly women, 4 = only women. The majority of
males (51%) and females (59%) thought that men and women are equally likely to initiate
kissing before sex [
Χ
2
(4, N = 248) = 6.99, p =.136, ns]. In contrast, the majority of males
(70%) and females (64%) agreed that women are more prone to initiate kissing after sex,
[
Χ
2
(4, N = 242) = 12.25, p =.016].
Based on a five point Likert scale ranging from 0 = never to 1 = always, participants
were asked how often they wanted to kiss either their long- or short-term partner after
experiencing an orgasm. A 2 (sex of respondent) X 2 (relationship status) ANOVA
revealed a main effect for relationship status. Respondents wanted to kiss a long-term
partner more often after having an orgasm (M = 2.77, SE = 0.09) than a short-term partner,
(M = 1.69 SE = 0.09), F(1, 166) = 146.70, p = .000, partial η
2
=.469. There were no
significant sex differences and no significant interaction between sex of respondent and
relationship status.
Bonding and Relationships
Participants were asked the degree to which they thought kissing after sexual
intercourse creates a bond between them and their long- or short-term partner (based on a
five point Likert scale of 0 = not at all to 4 = extremely so). A 2 (sex of respondent) X 2
(relationship status) ANOVA revealed a main effect for relationship. Both sexes thought
that a greater bond was created by kissing after sex with a long-term partner (M = 2.62, SE
= 0.08) than with a short-term partner, (M = 1.37, SE = 0.08), F(1, 201) = 205.39, p = .000,
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partial η
2
=.505. There were no significant sex differences and no interaction between sex
of respondent and relationship status factors.
The participants were asked to rate how emotionally close they felt after kissing a
long- or short-term partner on a five point Likert scale of 0 = not at all closer to 4 =
extremely closer. A 2 (sex of respondent) X 2 (relationship status) ANOVA was conducted.
Although there was no sex difference, the results showed a main effect for relationship
status. Respondents felt emotionally closer to their long-term partner (M = 2.79, SE = 0.07)
after kissing than to their short-term partner, (M = 1.70, SE = 0.08), F(1, 217) = 172.86, p =
.000, partial η
2
=.443. There was no a significant interaction between sex of respondent
and relationship status factors.
Salivary Exchange
Participants were asked to indicate their preference for tongue contact during a first
kiss (based on a Likert scale of 0 = no tongue and 4 = a lot of tongue). There was a main
effect for sex of respondent, with males (M = 2.49, SE = 0.13), preferring more tongue
contact than females (M = 2.09, SE = 0.06), F(1, 224) = 7.48, p =.007, partial η
2
= .032.
There was also a main effect for relationship status, with respondents preferring more
tongue contact with a short-term partner (M = 2.41, SE = 0.10) than a long-term partner (M
= 2.17, SE = 0.08), F(1, 224) = 4.41, p =.097, partial η
2
= .019. However, there was no
significant interaction.
How much tongue contact was preferred when kissing a long- or short-term partner
before having sex was assessed using a five point Likert scale of 0 = no tongue contact to 4
= a lot of tongue contact. A 2 (sex of respondent) X 2 (relationship status) ANOVA
revealed a main effect for relationship. Before having sex, respondents preferred more
tongue contact when kissing a long-term partner (M = 2.73, SE = 0.09) than a short-term
partner, (M = 2.55, SE = 0.09), F(1, 189) = 4.84, p = .029, partial η
2
=.025. There were no
significant sex differences and no significant interaction between sex of respondent and
relationship status factors.
Attractiveness and Kissing
Respondents rated how willing they would be to kiss or have sex with someone
they were not attracted to on a Likert scale of 0 = never and 4 = always. A 2 (sex of
respondent) X 2 (activity) ANOVA showed a main effect for sex of respondent. Males (M
= 1.13, SE = 0.10) were more willing to kiss or have sex with someone they were not
attracted to than females (M = 0.57, SE = 0.05), F(1, 241) = 25.57, p =.000, partial η
2
=
.096. But respondents of both sexes were more willing to kiss someone they are not
attracted to (M = 0.97, SE = .006), than to have sex with someone they are not attracted to
(M = 0.74, SE = 0.06), F(1, 241) = 14.31, p =.000, partial η
2
= .056. There was a significant
interaction between sex of respondent and these activities, F(1, 241) = 20.63, p =.000,
partial η
2
= .079. When comparing responses to both questions, post hoc paired-samples t-
tests revealed that for males there was no difference in likelihood of kissing someone (M =
1.11, SD = 0.91) and having sex with someone (M = 1.15, SD = 1.2) they were not attracted
to, t(44) = -.340, p = .736, whereas females were less likely to have sex with someone (M =
.33, SD = 0.61) they were not attracted to than to kiss them (M = .81, SD = 0.73), t(197) =
10.31, p = .000, η
2
= .350.
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Kissing
Study 3
Methods
The third study examined the perceived importance of kissing practices, attitudes
toward kissing, and an assessment of kissing partners. This questionnaire was completed by
another sample of 267 undergraduate students (71 males and 196 females), 92.8% were in
the age range of 18-24 with the remainder being 25 and or above. All participants reported
having experienced romantically kissing and only those who indicated a preference for
kissing “only” or “mostly” the opposite sex were included for the analysis, yielding a
sample of 250 (69 males and 181 females). Of the participants, 12% reported kissing 1-2
partners, 21% 3-5 partners, 28% 6-10 partners, 23% 11-20 partners, and 16% kissed 21 or
more partners. Sixty-one percent indicated that they were currently in a committed
romantic relationship.
Results
Kissing and Sexual Behavior
Participants were asked if they would want to have sex with someone who is a bad
kisser, based on a 5-point Likert scale from 1 = not at all to 4 = extremely likely. As shown
in Figure 4, males (M = 2.23, SD = 0.87) were much more likely than females (M = 1.24,
SD = 0.88) to have sex with someone who was a bad kisser, t(232) = 7.68, p = .000,
significant using a Bonferroni correction, η
2
= .203.
Participants were asked whether they would kiss someone that they knew only
wanted to have sex and did not want a relationship. Based on a five point Likert scale from
0 = not at all to 4 = extremely likely, males (M = 2.53, SD = 1.28) were more likely to have
sex with someone that did not want a relationship than were females (M = 0.78, SD = 0.90),
t(239) = 11.87, p =.000, significant using a Bonferroni correction, η
2
= .369. Males (M =
2.20, SD = 1.18) were also more likely than females (M = 1.07, SD = 1.14) to kiss someone
that they wanted to have sex with and did not want to have a relationship with, t(237) =
6.75, p = .000, significant using a Bonferroni correction, η
2
= .161.
As shown in Table 1, when asked to rate which factors are important for a good
kiss, several sex differences emerged. More males than females indicated that a good kiss is
one where their partner lets them initiate tongue contact, where kissing leads to sex, and
their partner makes moaning noises. No other features showed significant sex differences.
Salivary Exchange and Jealousy
Jealousy was measured on a five point Likert scale (0 = not at all jealous to 4 =
extremely jealous) in response to a hypothetical situation where the respondent discovers
that their long-term partner kissed someone of the opposite sex on the lips with either
tongue or no tongue contact. A 2 (sex of respondent) X 2 (tongue contact) ANOVA
revealed a main effect for sex of respondent, with females (M = 3.23, SD = 0.08) showing
more jealousy than males (M = 2.60, SD = 0.13), F(1, 163) = 17.50, p = .000, partial η
2
=
.097. There was also a main effect for tongue contact, with respondents showing more
jealousy when their partner kissed someone else using tongue (M = 3.15, SD = 0.08) as
compared to no tongue contact (M = 2.68, SD = 0.09), F(1, 163) = 53.70, p = .000, partial
η
2
= .248. There was no significant interaction.
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Kissing
Figure 4. Based on a five-point Likert scale (where 0 = not at all likely and 4 = extremely likely), the mean
ratings of the likelihood of having sex with someone who is a bad kisser for males (n = 63) and females (n =
171).
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Males Females
How likely would you have sex with someone who is a bad
kisser?
Mean Rating
Table 1. What factors are generally important as to what makes a kiss good (based on a five-point Likert
scale of 0 = not at all to 4 = extremely important).
Sex N Mean SD df t p η
2
My partner initiates kissing / is more
assertive
male 69 2.25 0.88 248 -1.29 0.199
female 181 2.40 0.85
My partner initiates tongue contact male 69 2.25 0.88 248 1.04 0.298
female 181 2.11 0.94
My partner lets me initiate tongue
contact
male 69 2.35 0.80 247 3.37 0.001 .044
female 180 1.92 0.92
The scent of partner’s body male 69 2.81 0.79 248 -0.85 0.396
female 181 2.91 0.85
The amount of touching/physical
contact/caressing while kissing
male 69 3.12 0.61 248 1.60 0.112
female 181 2.96 0.70
The kissing leads to sex male 68 1.97 1.20 242 5.41 0.000 .108
female 176 1.16 0.99
My partner makes moaning noises male 68 1.87 1.17 243 6.59 0.000 .152
female 177 0.87 1.01
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Kissing
Attractiveness and Kissing
To assess the importance of physical appearance when making the decision to kiss
someone, participants were asked to rate certain traits on a five-point Likert scale (0 = not
at all important to 4 = extremely important). A shown in Table 2, there were several sex
differences. Females rated the appearance of healthy teeth as being more important than
males, whereas males placed more importance on facial attractiveness, the attractiveness of
the person’s body, and their weight.
Table 2. How important are the following physical factors when deciding whether or not you want to kiss
someone (based on a five-point Likert scale of 0 = not at all to 4 = extremely important).
Sex N Mean SD df t p η
2
Healthy appearance of someone’s teeth male 68 2.60 0.83 246 -2.86 0.005 .032
female 180 2.92 0.77
Attractiveness of someone’s face male 69 2.93 0.67 247 2.09 0.037 .017
female 180 2.71 0.75
Attractiveness of someone’s body male 69 2.78 0.68 247 3.65 0.000 .051
female 180 2.41 0.75
Attractiveness of someone’s lips male 67 2.52 0.73 245 0.45 0.650
female 180 2.47 0.90
Person's weight (how heavy the person is) male 69 2.38 0.96 246 2.41 0.016 .023
female 179 2.04 0.98
Person has a healthy complexion (clear skin) male 69 2.48 0.85 246 1.05 0.293
female 179 2.35 0.89
Person has soft lips male 69 2.41 0.86 246 -0.32 0.752
female 179 2.45 0.94
Person has full lips male 68 2.12 0.80 245 1.00 0.318
female 179 1.97 1.09
Discussion
Our results support previous findings in showing a high incidence of kissing
between romantic and/or sexual partners (Dunne, Donald, Lucke, Nilsson, Ballard, and
Raphael, 1994; Youn, 1996). Out of 1,041 respondents, all aged 18 or older, only 5
individuals reported never having romantically kissed another person. Approximately 70%
of the sample acknowledged kissing 6 or more people, while 20% estimated having kissed
more than 20 people. There were no sex differences in the number of kissing partners, nor
were there sex differences in the age of experiencing one’s first romantic kiss.
Our hypothesis that females place a greater emphasis on kissing for making mate
assessments was consistent with several results. Our data show that females are more likely
to base evaluations of their partners' kissing ability on chemical cues (i.e., the breath and
the taste of their mouth), and for females an important physical feature in deciding whether
to kiss someone was the appearance of their teeth. Kissing could provide information about
a person’s health and hormonal status since sebaceous glands are located in high density on
the face and are regulated by sex hormones (Durham, et al, 1993; Hoshi, et al., 2002;
Nicholson, 1984; Rosenberg, 2002; Service, 1998). The taste and the smell of an
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Kissing
individual's mouth can also be indicative of underlying health problems (Durham, et al.,
1993; Hoshi, et al., 2002; Rosenberg, 2002; Service, 1998).
Our first hypothesis was also supported by the fact that fewer females than males
were willing to have sexual intercourse without kissing their partners first. Females also felt
that a male who is a bad kisser is less attractive/desirable. Previous studies have shown that
during initial dating with a romantic partner, women wanted physical contact, hugging, and
sensuous kissing, whereas males wanted to touch their partner’s breasts and genitals
(McCabe and Collins, 1984). Together these findings suggest that females place more
importance on kissing, and are more reliant on kissing as a mate assessment technique. In
addition to assessing the health of a prospective mate, kissing may enable females to assess
her partner’s level of commitment.
At the moment of a kiss, there is an exceedingly rich and complex exchange of
postural, tactile, and chemical cues. As evidence for just how biologically important this
exchange can be, one of us (Gallup) recently completed an unrelated survey which included
the question “Have you ever found yourself attracted to someone, only to discover after
kissing them for the first time that you were no longer interested?” Out of 58 male
respondents, 59% answered “yes,” and 66% of 122 female respondents also answered in
the affirmative. Thus, what transpires during an initial kiss can have a profound effect on
the future of that relationship. Perhaps kissing in these instances may activate evolved
mechanisms that function to discourage reproduction among individuals who could be
genetically incompatible.
Whereas males tended to place less importance on kissing, our prediction that they
would prefer wetter kisses, more tongue contact, and open mouth kisses was confirmed.
Males showed a greater preference for tongue contact and open mouth when kissing short-
term partners, and when sharing a first kiss with someone they would like to have a long-
term relationship with, males wanted more tongue involvement. Males also consider a
“good kiss” as one where their partner lets them initiate tongue contact. It is possible that
kissing styles that maximize salivary exchange provide subtle information about a female’s
reproductive status since saliva and breath odor change across the menstrual cycle
(Fullagar, 2003; McCann and Bonci, 2001). Because males have reduced chemosensory
detection in comparison to females, they may also need greater salivary exchange in order
to respond to various components in a female’s saliva. In addition, male preference for
salivary exchange could function to introduce substances such as hormones or proteins into
women’s mouths that may influence their mating psychology, and even make them more
sexually receptive. Studies have shown that the mucosa membrane inside the mouth is
permeable to hormones such as testosterone that are found in saliva (Dobs, Matsumoto,
Wang, and Kipnes, 2004). Buccal administration of substances into the mouth mucosa
circumvents hepatic first-pass and digestive degradation and provides a direct route to
systemic circulation (van Eyk and van der Bijl, 2004). Paralleling vaginal lubrication in
response to sexual arousal, males may also perceive increased moisture when kissing as a
sign of greater sexual receptivity on the part of their partner. It is interesting to note that
whereas both sexes preferred more tongue contact when kissing a long term partner,
especially just before sex, when it comes to first kisses, both sexes indicated that they
preferred more tongue contact with someone intended to be a short-term mate. We suspect
that more tongue contact during an initial encounter may aid in mate assessment and/or
function to increase arousal and likelihood to have casual sex.
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Males were less discriminating when it comes to deciding who to kiss or who to
have sex with. They were more willing to have sex with someone without kissing, to have
sex with someone they are not attracted to, and agree to have sex with someone they
considered to be a “bad kisser.” These findings are consistent with evidence that males tend
to be opportunistic maters (Symons, 1979) and further support our hypothesis that males
may not place as much importance on using kissing to make mate assessments.
Male sexual attraction evolved to put a premium on female features that signal
reproductive viability (Thornhill and Grammer, 1999; Scheib, Gangestad, and Thornhill,
1999). We found that males placed more emphasis on their partner’s face, body, and weight
as focal characteristics they use to decide whether to kiss someone. These preferences
mirror the physical features that men use when selecting mating partners and/or cues for
detecting a female’s reproductive status (Buss, Shackelford, Kirkpatrick and Larsen, 2001;
Rozin and Fallon, 1988).
Several findings support our second hypothesis that both males and females use
kissing as a bonding mechanism and place more importance on kissing long-term than
short-term partners. First, both sexes felt that kissing a long-term partner creates greater
emotional closeness. Second, both sexes agreed that kissing after sex creates more of a
bond with their long-term partner than short-term partner, and they indicated wanting to
kiss their long-term partner after experiencing an orgasm more often than a short-term
partner. Third, both sexes were less likely to have sex without kissing a long-term partner
than a short-term partner. Our data, however, suggest that the connection between kissing
and bonding may not be driven by a conscious component. The majority of males and
females agreed they would not begin a relationship with someone simply because they
were a good kisser.
Several findings also support our hypothesis that females appear to place a greater
emphasis on kissing to induce bonding. In long-term relationships, females not only rated
kissing as more important, but they indicated that kissing was important throughout a
relationship, whereas males place less importance on kissing as the relationship progresses.
Although one might expect males to place just as much importance on kissing over the
course of a long-term relationship, our data suggest that kissing as a bonding function may
be less important for males as it is to induce sexual arousal. Furthermore, females placed
more importance on kissing before, during, and after sexual intercourse, regardless of
whether it is with a long-term or short-term relationship. Both sexes also agreed that
females are more likely to initiate kissing after sexual intercourse. This supports other
findings in showing that males tend to engage in a hasty post-copulatory departure and
demonstrate an emotional shift after sexual intercourse to reduce the likelihood of bonding
and investment in short-term mating partners (Haselton and Buss, 2001).
Females were less likely to kiss someone they knew only wanted sex. Whereas
males were more likely to have sex without kissing a short-term partner, females were
equally unlikely to have sex without kissing either a short- or long-term partner. Females
also indicated being more jealous than males if they caught their short-or long-term partner
kissing someone else, a finding that supports previous studies showing that women are
more upset by the prospect of their partner kissing someone else (Buunk and Hupka, 1987)
and are more upset by the prospect of emotional infidelity (Buss, Larsen, Semmelroth, and
Westen, 1992).
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More males than females used kissing in an attempt to end a fight. Kissing as a
reconciliation gesture has been observed in other primates. For instance, bonobos and
common chimpanzees have been shown to kiss and embrace after fights, as an ostensible
means of conflict resolution (de Waal and van Roosmalen, 1979; de Waal, 2000). Kissing
is also used by female chimpanzees to acquire food from males (de Waal, 2000). In
humans, there is evidence that conflict resolution is facilitated with increasing amounts of
kissing (Gulledge, et al., 2003), and our data show that this may be principally male-
initiated.
In support of our third hypothesis, kissing seems to be viewed by both sexes as an
activity that can increase sexual arousal and receptivity, and may facilitate the occurrence
of sexual intercourse. Both males and females felt that both sexes initiate kissing before sex
and view kissing before sex as more important than kissing during or after sex, whether it is
with a short- or long-term partner. Furthermore, both men and women report that the ability
to kiss well contributes to making someone “a good lover” (Lewis and Clift, 2001, p. 26).
Kissing styles that enhance salivary exchange are seen as a way to increase the
arousal of a partner. Both sexes wanted to have more tongue contact before having sex with
a long-term partner than a short-term partner. As predicted, both sexes also reported that
they would be more jealous if they saw their partner kiss someone else with tongue contact,
suggesting, that a tongue kiss signals intent to engage in sexual intercourse with the extra-
pair partner.
Overall, our data show that males feel kissing should lead to sex more often than do
females. Whereas females felt there was a greater likelihood that kissing should lead to sex
with a long-term partner than a short-term partner, males felt that in either instance, kissing
should lead to sex. Males also categorized a “good kiss” as one that leads to sex and one
where “my partner makes moaning noises,” which may signal arousal and receptivity. Men
rate kissing as more “erotic” than do women (Suman, 1997) and more men consider “deep
kissing (French or tongue kissing)” as having sex (Pitts and Rahman , 2001 p.171).
It is important to acknowledge several limitations of our study. Our sample
consisted of mainly college-aged students and these findings may not necessarily
generalize to older or more heterogeneous adults. Furthermore, the functions of kissing
proposed here may not be the same for those who are married and/or have children. This
study is also limited by the fact that we relied on self-reports rather than direct observation
or experimental manipulations and causality cannot be inferred from our analyses. Future
investigations examining the incidence of mouth contact and saliva exchange in non-sexual
romantic kissing situations (e.g., parent-child kissing) would also help clarify the
distinction between different categories of kissing.
Nonetheless, this study provides evidence that romantic kissing may have evolved
as an adaptive courtship strategy that functions as a mate-assessment technique, a means of
initiating sexual arousal and receptivity, and a way of maintaining a bonded relationship.
While both sexes participate in the adaptive benefits of kissing, we found sex differences
when considering the pursuit of short- versus long-term mating strategies. We suspect that
overall, women place a greater importance on kissing not only to make more judicious
mate assessments, but for those in committed relationships kissing is used (wittingly or not)
to update, monitor, and assess the status of their partner’s continuing commitment (or lack
thereof) to the relationship. Males tend to employ romantic kissing as a means of increasing
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sexual receptivity and gaining sexual access, to affect conflict resolution, and to possibly
monitor the fertility of his mate.
Acknowledgements: We thank Allegra R. Edelman, Amy J. LeFevre, Jennifer A. Davis,
Franco Dispenza, R. Nathan Pipitone, and Andrew C. Gallup for help in data collection.
Received 30 April 2007; Revision submitted 07 August 2007; Accepted 13 August
2007
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... This tactic may also be very effective due to kissing playing a role in mate assessment. Hughes et al. (2007) and Wlodarski and Dunbar (2013) report that women use kissing to perform a chemosensory analysis of men's genetic fitness. Thus, if a woman consents to give a male a kiss she may be able to make a more informed decision about the male's genetic quality possibly removing any doubts she may have about this man's genetic fitness. ...
... Thus, if a woman consents to give a male a kiss she may be able to make a more informed decision about the male's genetic quality possibly removing any doubts she may have about this man's genetic fitness. Men, being more opportunistic maters, can use kissing to stimulate a woman's libido via the introduction of additional testosterone into her system (Hughes et al., 2007;Wlodarski & Dunbar, 2013). Additionally, both sexes use kissing to facilitate bonding with mates since oxytocin is released during kissing (Hughes et al., 2007;Wlodarski & Dunbar, 2013). ...
... Men, being more opportunistic maters, can use kissing to stimulate a woman's libido via the introduction of additional testosterone into her system (Hughes et al., 2007;Wlodarski & Dunbar, 2013). Additionally, both sexes use kissing to facilitate bonding with mates since oxytocin is released during kissing (Hughes et al., 2007;Wlodarski & Dunbar, 2013). It is possible that a woman may view a man who asks for a kiss as being respectful since he is asking rather than just taking the kiss, which often occurs in hookup contexts (see Flack et al., 2007), and perceived as warm, which women usually find appealing (Buss, 1989;Buss & Barnes, 1986;Buss & Schmitt, 1993). ...
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While a great deal of psychological research has been conducted on sex-specific mate choice preferences, relatively little attention has been directed toward how heterosexual men and women solicit short-term sexual partners, and which acts are perceived to be the most effective. The present research relied on an act nomination methodology with the goal of determining which actions are used by men and women to solicit a short-term “hook-up” partner (study 1) and then determine which of these actions are perceived as most effective by men and women (study 2). Using sexual strategy theory, we hypothesized that actions that suggest sexual access would be nominated most often by women whereas actions that suggest a willingness to commit were expected to be nominated most often by men. Additionally, men and women were predicted to rate actions by men that suggest a willingness to commit as most effective and actions by women that suggest sexual access as most effective. The results were consistent with these hypotheses. These findings are discussed in the context of both short- and long-term mating strategies and mate solicitation. The relationship between motivation, sexual strategies, and sexual behavior are examined, along with the need for research on the hookup tactics and motivations of self-identifying gay, lesbian, and bisexual individuals.
... A U.S. national survey found that 87% of respondents reported kissing in their most recent sexual event (Herbenick et al., 2019). Intimate kissing often is used to signal interest in sex (Moore, Kulibert, & Thompson, 2017), increase arousal between partners (O'Sullivan, Cheng, Harris, & Brooks-Gunn, 2007), sustain feelings of closeness and arousal before, during and after sexual behaviours (Jankowiak, Volsche, & Garcia, 2015), and promote emotional connection (Garcia, Cavalie, Goins, & King, 2008;Hughes, Harrison, & Gallup, 2007). Intimate kissing is a key component of postcoital interactions for couples (Hughes & Kruger, 2011;Muise, Giang, & Impett, 2014) and significantly contributes to romantic and sexual satisfaction (Heiman et al., 2011;Kulibert, Moore, Dertinger, & Thompson, 2019). ...
... The few studies that have assessed intimate kissing in some detail tend to have focused on its significance as it relates to larger concepts. Such concepts include kissing as an early milestone in the onset of adolescent partnered sexual activity (O'Sullivan et al., 2007;Welsh, Haugen, Widman, Darling, & Grello, 2005), its role in assessing mate desirability (Hughes et al., 2007) and genetic fitness through chemosensory analysis (Thornhill et al., 2003), and possible (although challenged) universality across cultures (Jankowiak et al., 2015;Murray, Fessler, Kerry, White, & Marin, 2017). One study differentiated between gentle (lip-to-lip contact) and deep (using tongue) kissing and found them both to heighten arousal and passion (Frederick, Lever, Gillespie, & Garcia, 2017). ...
... Kissing is a relevant experience in the development and broadening of sexual identities, with relevance to people with both same-sex and different-sex attractions (Knox, Beaver, & Kriskute, 2011;Lannutti & Denes, 2012;Smiler, Frankel, & Savin-Williams, 2011). Although there is no obvious taxonomy of intimate kisses, kisses vary in terms of physical features, such as a partner's scent, dental hygiene, kissing technique, and the amount of physical contact involved (Hughes et al., 2007). ...
Article
Intimate kissing is often viewed as a preliminary or ancillary behaviour in studies exploring sexual interactions. There is a lack of research that focuses on differentiating the types of intimate kisses, including the contexts in which they occur, and desirable and undesirable features. The current study was designed to assess memories of first, best, forbidden and worst kisses. Participants were 691 U.S. adults (mean age 32.27 years; 55% identified as male) who completed an online survey addressing kissing attitudes and experiences using both structured and open-ended survey tools. Four themes emerged through content analysis: physical components, connection to the partner, context, and emotions evoked; and these are discussed for all four types of kissing memories. Findings are discussed in terms of embodiment that intimate kisses capture, their role as a metric of one's attraction to a partner, and the means by which kissing experiences might solidify a sense of oneself as a sexual person.
... For comparative data, Hughes et al. 23) reported that in an American university > 99% of college students (1,041 respondents) answered affirmatively for romantic kissing. However the age distribution of this study sample varied differently: 93.6% (in the range of 18-24 years) and 6.4% ('25 and above' years). ...
... However the age distribution of this study sample varied differently: 93.6% (in the range of 18-24 years) and 6.4% ('25 and above' years). The inferences of Hughes et al. 23) were, (1) women place more importance on kissing as a mate assessment device and as a means of initiating, maintaining and monitoring the current status of their relationship with a long term partner. (2) men appear to use kissing to increase the likelihood of having sex. ...
... In addition, Regan et al. 24) had reported on the first kiss experience in a convenience sample of 356 university students (169 men and 187 women, average age 24.9 years). It should be noted that the studies of Hughes et al. 23) and Regan et al. 24) were conducted in the USA. Unfortunately, due to institutional policies on "student privacy" in Japan, it would be a hassle to elicit such type of information from our study sample. ...
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Objective: Two fold. (1) to quantitate what percentage of university entering freshmen in the 2 nd decade of the 21 st century in Japan, have engaged in romantic kissing. (2) To investigate humor sense in the personal definition of 'kiss', as comprehended by the Japanese undergraduate students. Design: Two prospective, interrelated questionnaire studies were conducted on 366 freshmen and sophomores (148 men and 218 women) aged 18-20 years, from a national university located in the Tokai region of Japan. Study 1, elicited 'yes-no' responses to the question, 'Have you engaged in kissing a romantic partner?'. Study 2, solicited a personal definition to the question, 'What is a kiss?', within 5 minutes. Both studies were conducted in class room setting. Results: 41.8% and 39.9% for men and women respectively answered 'Yes' to having kissed a romantic partner. Humorous, idiosyncratic definitions on kiss by 29 men and 24 women students respectively are presented. 'Communication' and 'mind' are two keywords which were incorporated in such humorous definitions. Among the 53 emanations, what we consider as one of the best is included in the title of this report. Conclusions: The data collected lead us to the hypothesis that among young couples in Japan, mutual kissing by romantic partners may be considered as the idiomatic 'Crossing the Rubicon' line towards sexual intercourse. This hypothesis deserves independent verification in the future.
... SCT also leaves space for other dimensions, such as action/ behavior orientation. This refers to interests, approaches, and attractions to specific sexual behaviors or practices and is relevant when thinking about orientation across contexts, given that interests in specific behaviors may branch, like kissing (Herbenick et al., 2019;Hughes et al., 2007). In many cultures, lip-to-lip kissing is prevalent for in-person sexuality (Herbenick et al., 2019;Hsu et al., 1994;Noorishad et al., 2019;Person et al., 1989). ...
Article
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Sexual orientation describes sexual interests, approaches, arousals, and attractions. People experience these interests and attractions in a number of contexts, including in-person sexuality, fantasy, and porn use, among others. The extent to which sexual orientation is divergent (branched) and/or overlapping (coincident) across these, however, is unclear. In the present study, a gender/sex and sexually diverse sample (N = 30; 15 gender/sex/ual minorities and 15 majorities) manipulated digital circles representing porn use, in-person sexuality, and fantasy on a tablet during in-person interviews. Participants used circle overlap to represent the degree of shared sexual interests across contexts and circle size to indicate the strength and/or number of sexual interests within contexts. Across multiple dimensions of sexual orientation (gender/sex, partner number, and action/behavior), we found evidence that sexual interests were both branched and coincident. These findings contribute to new understandings about the multifaceted nature of sexual orientations across contexts and provide a novel way to measure, conceptualize, and understand sexual orientation in context.
... This characteristic of the research is important because the type and length of the relationship that individuals are in influence the context and purposes of kissing. This is especially relevant since kissing is seen as a more intimate behavior than even intercourse for some people, and as such is often less common in casual or newer relationships during sexual encounters (Herbenick et al., 2019;Hughes, Harrison, & Gallup, 2007). Because our interest is in the role of kissing as a bellwether in more committed relationship, we control for relationship length and context in two ways. ...
Article
In this study we explored how the amount of kissing during the most recent sexual experience (specific kissing) and amount of kissing during the last year (global kissing) were both associated with the quality of the sexual relationship and overall relationship satisfaction and dissatisfaction. To understand these associations, we obtained surveys from a national sample of 878 participants who had been in a romantic relationship for at least two years. We evaluated their results through a structural equation model and found that for women the rates of specific kissing were associated with their ability to orgasm, sexual frequency, and indirectly to sexual satisfaction. For both men and women, measures of global kissing were associated with both sexual and relationship satisfaction but more strongly with measures of sexual and relationship dissatisfaction. These findings suggest that measures of kissing could be used as a bellwether of both the quality of the sexual relationship for women and of feelings of dissatisfaction about both the sexual and overall relationship for both sexes.
... During the interactions, a subset of couples kissed. We were somewhat surprised, but also saw an opportunity: kissing is a well-documented display of affection in the United States (e.g., Hughes, Harrison, & Gallup, 2007;Welsh, Haugen, Widman, Darling, & Grello, 2005), signifies social connection worldwide (Eibl-Eibesfeldt, 1970), and yet its presence in this laboratory context is not normative. As such, we view the presence of kissing as a strong signal of the construct of interestbehavioral intimacy as measured by affectionate touch. ...
Article
Full-text available
Affectionate touch is an important behavior in close relationships throughout the lifespan. Research has investigated the relational and individual psychological and physical benefits of affectionate touch, but the situational factors that give rise to it have been overlooked. Theorizing from the interpersonal process model of intimacy, the current studies tested whether perceived partner responsiveness forecasts affectionate touch in romantic couples. Following a preliminary integrative data analysis ( N = 842), three prospective studies use ecologically valid behavioral (Studies 1 and 2) and daily (Studies 2 and 3) data, showing a positive association between perceived partner responsiveness and affectionate touch. Furthermore, in Study 3, we tested a theoretical extension of the interpersonal process of intimacy, finding that affectionate touch forecasts the partner’s perception of the touch-giver’s responsiveness the next day. Findings suggest affectionate touch may be an untested mechanism at the heart of the interpersonal process of intimacy.
... different receptors and neural pathways from affective touch, which is used in social communication and emotional expression [28], [51]. There is an extensive amount of research revealing the important role of affective touch in increasing positive social behaviours (the Midas Touch effect) [6], building bonds [19], [25] and communicating emotions [18] in human interaction. Affective touch also has effects on our physiological measures, indicating a more innate and universal link between haptic stimulation and physical wellbeing. ...
Article
Full-text available
Various communication systems have been developed to integrate the haptic channel in digital communication. Future directions of such haptic technologies are moving towards realistic virtual reality applications and human-robot social interaction. With the digitisation of touch, robots equipped with touch sensors and actuators can communicate with humans on a more emotional and intimate level, such as sharing a hug or kiss just like humans do. This paper presents the design guideline, implementation and evaluations of a novel haptic kissing machine for smart phones - the Kissenger machine. The key novelties and contributions of the paper are: (i) A novel haptic kissing device for mobile phones, which uses dynamic perpendicular force stimulation to transmit realistic sensations of kissing in order to enhance intimacy and emotional connection of digital communication; (ii) Extensive evaluations of the Kissenger machine, including a lab experiment that compares mediated kissing with Kissenger to real kissing, a unique haptic Turing test that involves the first academic study of human-machine kiss, and a field study of the effects of Kissenger on long distance relationships.
Chapter
Human love signals are nonverbal signs of sexual attraction, courtship, seduction, and love. Myriad signs, signals, and cues of attraction are in service to what the authors call the “reproductive force,” the fifth fundamental force of nature after the strong, weak, electromagnetic, and gravitational forces of physics. The reproductive force appeared some 3.7 billion years ago with RNA and later, DNA, in the origin of life on Earth. RNA and DNA molecules encode information (via codons) about how to reproduce themselves. Selfishly enforced, guided, and shaped by primordial messaging molecules, self-replication became the prime directive—the summum bonum or “greatest good”—of life and living, pursued for its own sake and solely on its own behalf. The reproductive force remains a potent motivator in humans today, in their overall demeanor, facial expressions, gestures, goals, clothing, automobiles, music, media, art, religion, hairdos, shoes, prom dresses, and diverse additional nonverbal signs and cues. This chapter explores the relationship between love signals and the overarching reproductive force.
Chapter
With advances in HCI and AI, and increasing prevalence of commercial social robots and chatbots, humans are communicating with computer interfaces for various applications in a wide range of settings. Kissenger is designed to bring HCI to the populist masses. In order to investigate the role of robotic kissing using the Kissenger device in HCI, the authors conducted a modified version of the imitation game described by Alan Turing by including the use of the kissing machine. Results show that robotic kissing has no effect on the winning rates of the male and female players during human-human communication, but it increases the winning rate of the female player when a chatbot is involved in the game.
Chapter
This chapter explores what love is, how it is related to intimacy, various definitions of both concepts, love in ancient times, the universality of love, the functions that love serves, romantic passion, and the relation of sexual satisfaction and love.
Chapter
This chapter discusses the sexual signaling and sexual aggression in adolescent relationships. It presents the results of a 1978 survey of Los Angeles teenagers designed to examine expectations for and communication about sex across gender. At most these survey data are descriptive of a particular population in a particular place at a particular point in time. Nevertheless, the data seem enormously informative of the magnitude of a serious social problem. They also examine and refute a previously untested assumption—that benign social change has been occurring in sexual socialization practices in step with increased knowledge about human sexuality and an increased thrust toward greater egalitarianism between the genders. The data indicate that adolescents view sexual aggression by the man against the woman as an ever-present and sometimes acceptable possibility in the context of intimate cross-gender encounters.
Article
Responses to the question, “What constitutes a romantic act?,” were obtained from 149 women and 48 men. Results suggest a large area of agreement and a small area of disagreement between the sexes as to the nature of romantic acts.
Article
Evidence has accumulated in recent years supporting the hypothesis that both facial and bodily physical attractiveness in humans are certifications of developmental and hormonal health. Such evidence indicates that physical attractiveness is an honest or Zahavian signal of phenotypic and genetic quality. The hypothesis that physical beauty connotes health was first proposed by Westermarck and was discussed later by Ellis and Symons. It has been suggested that facial attractiveness in women is a deceptive signal of youth, unrelated to phenotypic and genetic quality. This sensory-bias or super-stimulus hypothesis is not supported by this study of men’s ratings of the attractiveness of photographs of 92 nude women. Independent ratings of photographs of faces, fronts with faces covered, and backs of the same women are significantly, positively correlated. The correlation between the ratings of different photos implies that women’s faces and external bodies comprise a single ornament of honest mate value, apparently constructed during puberty by estrogen and also probably by developmental adaptations for symmetry. Thus, women’s physical attractiveness in face and body honestly signal hormonal and perhaps developmental health.
Article
Evidence has accumulated in recent years supporting the hypothesis that both facial and bodily physical attractiveness in humans are certifications of developmental and hormonal health. Such evidence indicates that physical attractiveness is an honest or Zahavian signal of phenotypic and genetic quality. The hypothesis that physical beauty connotes health was first proposed by Westermarck and was discussed later by Ellis and Symons. It has been suggested that facial attractiveness in women is a deceptive signal of youth, unrelated to phenotypic and genetic quality. This sensory-bias or super-stimulus hypothesis is not supported by this study of men’s ratings of the attractiveness of photographs of 92 nude women. Independent ratings of photographs of faces, fronts with faces covered, and backs of the same women are significantly, positively correlated. The correlation between the ratings of different photos implies that women’s faces and external bodies comprise a single ornament of honest mate value, apparently constructed during puberty by estrogen and also probably by developmental adaptations for symmetry. Thus, women’s physical attractiveness in face and body honestly signal hormonal and perhaps developmental health.
Article
Alexander (1979) has invited "⋯ biologists to contribute to the analysis of human behavior on all legitimate fronts⋯" He considered it "⋯ especially relevant that [they] take up the problem of relating human attributes to evolutionary history." The analysis of human sexual behavior surely qualifies as a legitimate topic in evolutionary biology. This chapter represents a contribution to the argument that sperm competition does occur in humans and has been a selective force in the evolution of certain human characteristics. There has been considerable controversy over what may be the "natural" sexual inclinations (promiscuous, polygynous, serially polygynous, monogamous, or some mixture of these) of human males (e.g., Trivers 1972; Wilson 1975; Alexander 1977; Short 1977, 1979, 1981; Daly and Wilson 1978; Symons 1979; Lovejoy 1981; Barash 1982; Harvey and Harcourt, this volume), but relatively much less debate over the sexual predilections of human females (Hrdy 1981). Females are widely assumed to be monogamous, with little formal recognition of alternative female strategies (but see Hrdy 1981, and Knowlton and Greenwell, this volume). The compromise view of human male mating strategy proposes mixed tactics (Trivers 1972) where males attempt to pair-bond with one or more females by high investment, and opportunistically (more or less promiscuously) mate with other females. All combinations of male tactics from rape (Shields and Shields 1983, Thornhill and Thornhill 1983) to high investment (Trivers 1972) and the environmental and social circumstances that occasion their expression have received analysis in the literature. As Hrdy (1981) observed: "The sociobiological literature stresses the travails of males - their quest for different females, the burdens of intra-sexual competition, the entire biological infrastructure for the double standard. No doubt this perspective has led to insights concerning male sexuality. But it has also effectively blocked progress toward understanding female sexuality - defined here as the readiness of a female to engage in sexual activity." The biological irony of the double standard is that males could not have been selected for promiscuity if historically females had always denied them opportunity for expression of the trait. If strict monogamy were the singular human female mating strategy, then only rape would place ejaculates in position to compete and the potential role of sperm competition as a force in human evolution would be substantially diminished. Here I shall explore the literature for evidence of the evolutionary significance of sperm competition in humans. I present data on the circumstances that would place ejaculates from different human males together in the reproductive tract of a female during a single reproductive cycle. I summarize the evidence that human sperm competition actually occurs. And, finally, I speculate on how selection within the context of potential or actual sperm competition may have operated in human evolutionary history to shape some aspects of human anatomy, physiology, behavior, and culture. © 2006 Springer Science+Business Media, Inc. All rights reserved.
Article
Past research demonstrates that sexual assault perpetration is caused by multiple factors including attitudes, early experiences, and situational factors. In this study, 343 college men described either a sexual assault they had committed or their worst date. Discriminant function analysis indicated that attitudes about gender roles and alcohol, number of consensual sex partners, how well the man knew the woman, how isolated the setting was, alcohol consumption during the event, the man's misperception of the woman's cues during the event, and prior consensual sexual activity between the man and the woman discriminated between sexual assaults and worst dates. Additionally, tactics used to obtain sex, self attributions, the perceived seriousness of the assault, and the extent to which it disrupted relationships with others significantly discriminated between men who committed forced sexual contact, sexual coercion, and rape. These results demonstrate the importance of considering both individual characteristics and situational factors in theories and prevention activities.