Although appearing nervous and awkward during an initial encounter with an attractive other may seem counterproductive for future mating success, the reaction may have potential adaptive value

Perceived Nervous Reactions during Initial Attraction and Their Potential Adaptive Value. Susan M. Hughes, Marissa A. Harrison & Kathleen M. de Haan. Adaptive Human Behavior and Physiology, Jan 7 2020. https://link.springer.com/article/10.1007/s40750-019-00127-y

Abstract
Objective: We sought to examine perceived nervous reactions when first interacting with a particularly attractive person/potential romantic partner. From a theoretical standpoint, we cogitate on the possible adaptive nature of these reactions that appear seemingly counterproductive for future mating success.

Methods: We documented 280 participants’ retrospective self-reports of experiencing a variety of physiological, vocal, and behavioral reactions during an initial encounter with a person they found highly attractive. We also asked participants to rate the reactions of others that they used to determine if another person was attracted to them.

Results: Participants reported most frequently experiencing increased attentiveness, smiling, staring, heart rate, giggling/laughter, blushing, and difficulty concentrating during this first encounter. Both sexes reported speaking faster and being less able to express themselves clearly, and women reported using a higher pitch and having a more unsteady tone of voice during an initial encounter of attraction. Further, participants reported observing similar nervous reactions by others whom they perceived were attracted to them. These findings were examined while considering individual differences in sociosexual orientation (i.e., propensity toward uncommitted sex), self-perceived mate value, empathy, and gender.

Conclusions: Participants reported that they did, indeed, experience a cluster of anxiety-related physiological and behavioral reactions during an initial encounter with someone they found highly attractive. Although appearing nervous and awkward during an initial encounter with an attractive other may seem counterproductive for future mating success, we discuss potential adaptive functions for displaying these responses.

Reasons why Nervous Responses during Initial Attraction May be Adaptive

Whereas it was our aim to document the cluster of nervous reactions upon initial
encounter, it is of interest to explore the adaptive function of these physiological
responses reported in this study. At first glance, it would not appear adaptive for
someone to display nervous reactions during an initial encounter with an attractive,
potential mate. These reactions may make an individual seem awkward, clumsy,
ignorant, and uncomfortable and may deter one from considering that person as a
potential mate. Even though these reactions seem counterproductive for future mating
success, our data show that people report they are prevalent. Because the reproductive
consequences of a behavior affect the incidence of that behavior in subsequent
generations, this cluster of nervous signs may serve some adaptive function. Below we
present six possible adaptive reasons why nervous reactions during an initial encounter
with a potential mate are common.

Strong, Honest Sign of Mate Interest

These nervous reactions may serve an adaptive
function of being a salient signal of reproductive interest. In particular, attraction/
romantic interest can be easily distinguished through vocal tones (Hughes et al.,
2010). It may be difficult to mask anxious reactions during this encounter. Particularly
for men, because nervousness can cause problems with cognitive performance
(Karremans et al., 2009; Sarason, 1984), nervousness may make it more difficult for
a man to disguise his true feelings and display phony traits during an initial encounter.
Therefore, these reactions may serve as an honest signal of interest when in the
presence of a potential mate. It is also adaptive to attend to cues of romantic interest
to either avoid or engage in expending energy on individuals who may or may not be
interested or available (Bendixen et al., 2019; Floyd, Judd, & Hesse, 2008).
Both male and female participants indeed reported experiencing several physiological and behavioral reactions when first talking in person to someone whom they found
highly attractive and deem a potential romantic partner. Although the documented
responses occur typically under conditions of “fight or flight” (Marks & Neese, 1994),
we argue that this cluster of signals can be thought of as a psychobiological signature of
honest interest, and these reactions in the presence of a potential mate may serve an
adaptive function of signaling reproductive interest, enhancing the chances of obtaining
a desired mate. Given that our sample was a good representation of peak reproductive
years (a mean of 29.1 with a standard deviation of 12.7 years; Dunson, Baird, &
Colombo, 2004), our participants likely had an increased opportunity to experience
these reactions during initial attraction compared to younger, traditional, college-age
samples typically recruited in other research.

Trigger Reciprocal Feelings

Signs of romantic interest often trigger reciprocal feelings
(Kenny & La Voie, 1982; Montoya & Insko, 2008), and as reported by our participants,
people use these nervous reactions to assess whether another person is attracted to
them. Research shows that when one is made aware that a person is attracted to them,
they become more attracted to that person; but people need to be aware of other’s
feelings toward them for strong reciprocal liking to occur (Luo & Zhang, 2009).
Noticing reciprocation of interest would be particularly advantageous so as to decrease
the chances of missing a mating opportunity and avoid the risk of being rejected.
More Effective Communication Research has shown that when put in a stressful
situation, some aspects speech quality decreases such that speech fluency (as measured
by pause time) is significantly reduced and the frequency of flustered speech increases
(Buchanan, Laures-Gore, & Duff, 2014; Kasl & Mahl, 1965). However, several other
aspects of speech quality are actually enhanced during stressful situations, perhaps
unbeknownst to the speaker. For instance, under instances of stress, communication
rate (words per minute) increases, productive language (ratio of productive to nonproductive speech) increases (which is particularly pronounced during the early part of a
speech task), the use of non-fluencies (such as hmm, uh, um, etc.) is less likely, and
word-finding difficulties do not seem to impair speech (Buchanan et al., 2014). Thus, it
can be argued that when a person becomes anxious when first speaking to someone to
whom they are attracted, their semantic communication is essentially more effective.
We also found that women reported raising the pitch of their voice, which may have
made them sound more attractive. Thus, these speech patterns that occur under the
stress of an initial interaction may actually enhance the chances of impressing and
attaining the desired mate.

Indication of Desirable Traits Associated with those Who Exhibit Nervous Behavior

Anxious individuals have been shown to be more adept at conveying positive
qualities and appeared more willing to engage; they appeared nicer, more interesting,
and more conversational, all of which could increase their desirability (Brumbaugh &
Fraley, 2010). A person who exhibits nervous reactions during initial attraction could
serve as an indication to a potential mate (particularly women) that the suitor possesses
other personality traits that would be favorable in long-term relationships and for future
parenting such as being sensitive, caring, and responsive.
People generally like those who are more facially expressive, and it is seen
as more attractive (Sabatelli & Rubin, 1986). As such, people show greater
facial movement during high versus low anxiety situations (Harrigan &
O’Connell, 1996), and nonverbal expressiveness positively impacts interpersonal
perceptions (Sabatelli & Rubin, 1986). Having a more expressive nature, including displaying nervousness, could also demonstrate other positive characteristics that people find attractive (Sabatelli & Rubin, 1986). In fact, nonverbal
expressiveness could even compensate for a lack of physical attractiveness and
may enhance initial interpersonal impressions so as to allow the person to
appear more attractive (Sabetelli & Rubin, 1986). Along these lines, previous
research has shown that men were more likely to be accepted as a potential
romantic partner during a speed-dating event when they arrived with elevated
levels of the stress hormone, cortisol (van der Meij et al., 2019) suggesting that
being nervous may have its advantages.

Sweating Allows for the Release of Pheromones

Nervously sweating during an initial encounter with an attractive, potential mate may increase the release of pheromones
which can serve as a chemical signal of attraction to the recipient (Saxton et al., 2008).
When individuals become anxious, they tend to show increased palmar sweat (Kasl &
Mahl, 1965) and body perspiration (Galassi et al., 1981) and there is evidence to
suggest that human pheromones are released through these axillary sweat glands (Beier,
Ginez, & Schaller, 2005). Pheromones signal sexual readiness in other species and
likely do so in humans (Thornhill, Chapman, & Gangestad, 2013) and can affect
perceptions of attraction in humans (Rantala, Eriksson, Vainikka, & Kortet, 2006;
Thornhill & Gangestad, 1999; Wyart et al., 2007). For instance, women who were
exposed to androstadienone, a purported male pheromone released by axillary sweat
glands, gave men at a speed dating event higher attractiveness ratings than did women
with no exposure (Saxton, Lyndon, Little, & Roberts, 2008). Exposure to
androstadienone appears to increase sexual response, increase focus, and improve
mood in women (Jacob, Hayreh, & McClintock, 2001; Hummer & McClintock,
2009; Jacob, Garcia, Hayreh, & McClintock, 2002; Verhaeghe, Gheysen, & Enzlin,
2013). Further, release of pheromones has been shown to be valuable for making mate
assessments and can facilitate quick judgments (Hummer & McClintock, 2009;
Thornhill & Gangestad, 1999).
Pheromones may have other direct influences on the recipient. Pheromone exposure
affects skin temperature and conductance (Jacob et al., 2001) and cortisol levels (Wyart
et al., 2007). Thus, it is possible that the recipient could interpret one’s own physiological arousal caused by the pheromone exposure to be the result of their own attraction to
the sender. In addition, there is some evidence from the animal kingdom that pheromones serve to appease conspecifics (Pageat & Gaultier, 2003). Indeed, empathetic
responses to signals in sweat have been documented in humans. Prehn-Kristensen et al.
(2009) found that exposure to sweat from individuals in anxiety-provoking situations
activated areas of the brain related to emotional processing and empathy regulation.
Future studies may explore how pheromones released during this nervous interaction
with a potential mate could influence human opposite-sex conspecifics.

Aid in the Assessment of Matching Mate Value

Mutual nervousness could reveal
matching mate value whereas if only one person is nervous and the other is not, then
this could be a sign of a mismatch in mate value. In other words, whether one, both, or
neither persons of the dyad experiences nervousness when meeting for the first time
could help to differentiate between those who have a matching mate value from those
who are discordant. Individuals generally tend to desire mates with some level of
similarity to themselves and who are of matching social desirability (Berscheid,
Walster, & Walster, 1971; Buston & Emlen, 2003; Figueredo, Sefcek, & Jones,
2006), which often reflects a desire for someone of matching mate value. Back et al.
(2011) argued that knowing one’s own mate value is essential to reproductive to
success. Further, one could view any arousal felt when reciprocating that attention
from a potential mate as a signal of matching mate value.