Frontpage - Social Sciences - Signs of attraction from men

Human Ovulation CuesMartie G. Haselton1,2,3,4 and Kelly Gildersleeve1,2University of California, Los Angeles 1Department of Psychology, 1285 Franz Hall, UCLA, Los Angeles, CA 900952Center for Behavior Evolution and Culture, 341 Haines Hall, UCLA, Los Angeles, CA 900953Department of Communication Studies, 2303 Rolfe Hall, UCLA, Los Angeles, CA 900954Institute for Society and Genetics, 1320 Rolfe Hall, UCLA, Los Angeles, CA 90095Corresponding author: Haselton, Martie G. (haselton@ucla.edu)8/10/15 (in press, Current Opinion in Psychology, Special Issue on Evolutionary Psychlogy)HighlightsRecent research reveals cues of ovulation in women that observers can detect.These include attractive changes in women’s scents, voices, and appearance.Observers respond to human ovulation cues behaviorally and hormonally.Nonetheless, it is likely that women have evolved to suppress ovulation cues.We outline research questions that will help to address lingering mysteries.AbstractIn most mammals, cues of impending ovulation—including changes in appearance and sexual behavior—mark the fertile phase within the ovulatory cycle. Such cues were long thought to have been completely concealed in humans. However, research over the past two decades has overturned this assumption, revealing subtle but detectable cues of ovulation to which observers respond both behaviorally and hormonally. We review research in this area over the last several years. Cues of ovulation in human females include attractive changes in scent, voice, and appearance. Women also appear to be more receptive and solicitous towards sexually attractive prospective mates when fertile within the cycle. We discuss reasons why human ovulation cues are subtle and outline questions for future research.Human Ovulation CuesIntroductionMale attraction to cues of ovulationFertility—the probability of conceiving from sex—varies across the mammalian ovulatory cycle, peaking just before ovulation and falling to zero immediately afterwards (see Figure 1). Ovulation is triggered by dramatic changes in hormones, with wide-ranging effects on female physiology and, possibly, their social interactions. If there are outward signs of ovulation, males who find them attractive will have a reproductive advantage over males who do not. So, have males evolved to detect ovulation? Across diverse species, female scents, behaviors, and appearance become more attractive to males approaching ovulation ADDIN EN.CITE <EndNote><Cite><Author>Nelson</Author><Year>2005</Year><RecNum>2</RecNum><DisplayText>[1]</DisplayText><record><rec-number>2</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">2</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Nelson, Randy J</author></authors></contributors><titles><title>An introduction to behavioral endocrinology</title></titles><dates><year>2005</year></dates><publisher>Sinauer Associates</publisher><isbn>0878936173</isbn><urls></urls></record></Cite></EndNote>[1]. For example, in chimpanzees and baboons, fertile females exhibit sexual swellings – marked increases in the volume and redness of their perineal skin – that are attractive to males. Female orangutans and gorillas instead exhibit subtle cues of ovulation ADDIN EN.CITE <EndNote><Cite><Author>Dixson</Author><Year>2012</Year><RecNum>4</RecNum><DisplayText>[2]</DisplayText><record><rec-number>4</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">4</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Dixson, Alan F</author></authors></contributors><titles><title>Primate Sexuality: Comparative Studies of the Prosimians, Monkeys, Apes, and Humans</title></titles><dates><year>2012</year></dates><publisher>Oxford University Press</publisher><isbn>0191624187</isbn><urls></urls></record></Cite></EndNote>[2]. Female gorillas, for example, have subtle labial swellings just before ovulation ADDIN EN.CITE <EndNote><Cite><Author>Nadler</Author><Year>1979</Year><RecNum>5</RecNum><DisplayText>[3]</DisplayText><record><rec-number>5</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">5</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Nadler, RD</author><author>Graham, CE</author><author>Collins, DC</author><author>Gould, KG</author></authors></contributors><titles><title>Plasma Gonadotropins, Prolactin, Gonadal Steroids, and Genital Swelling during the Menstrual Cycle of Lowland Gorillas*</title><secondary-title>Endocrinology</secondary-title><alt-title>Endocrin</alt-title></titles><periodical><full-title>Endocrinology</full-title></periodical><pages>290-296</pages><volume>105</volume><number>1</number><dates><year>1979</year></dates><isbn>0013-7227</isbn><urls></urls></record></Cite></EndNote>[3]. In addition, across diverse species, changes in scents mark fertility, and some males can even discern fertile from non-fertile cycles on the basis of scent (see review in ADDIN EN.CITE <EndNote><Cite><Author>Alberts</Author><Year>2006</Year><RecNum>58</RecNum><DisplayText>[4]</DisplayText><record><rec-number>58</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">58</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Alberts, S C</author><author>Buchan, JC</author><author>Almann, J</author></authors></contributors><titles><title>Sexual selection in wild baboons: From mating opportunities to paternity success</title><secondary-title>Animal Behaviour</secondary-title><alt-title>Anim Behav</alt-title></titles><periodical><full-title>Animal Behaviour</full-title></periodical><pages>1177-1196</pages><volume>71</volume><dates><year>2006</year></dates><urls></urls></record></Cite></EndNote>[4]). In sum, ovulation cues are common among mammals, including our closest primate relatives, but vary in magnitude and mode of expression.Assumption of concealed ovulation in humansScientists have long claimed that human sexuality was “emancipated” from hormonal control during evolution ADDIN EN.CITE <EndNote><Cite><Author>Symons</Author><Year>1979</Year><RecNum>6</RecNum><DisplayText>[2,5]</DisplayText><record><rec-number>6</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">6</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Symons, Donald</author></authors></contributors><titles><title>The evolution of human sexuality</title></titles><dates><year>1979</year></dates><pub-location>New York</pub-location><publisher>Oxford University Press</publisher><isbn>0195025350 9780195025354</isbn><urls></urls><remote-database-name>/z-wcorg/</remote-database-name><remote-database-provider> app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">4</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Dixson, Alan F</author></authors></contributors><titles><title>Primate Sexuality: Comparative Studies of the Prosimians, Monkeys, Apes, and Humans</title></titles><dates><year>2012</year></dates><publisher>Oxford University Press</publisher><isbn>0191624187</isbn><urls></urls></record></Cite></EndNote>[2,5]. However, new evidence indicates that human sexuality is influenced by the ovulatory cycle in nuanced ways ADDIN EN.CITE <EndNote><Cite><Author>Gangestad</Author><Year>2008</Year><RecNum>9</RecNum><DisplayText>[6,7]</DisplayText><record><rec-number>9</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">9</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Thornhill, Randy</author></authors></contributors><titles><title>Human oestrus</title><secondary-title>Proceedings of the Royal Society of London B: Biological Sciences</secondary-title><alt-title>Proc R Soc Lond B Biol Sci</alt-title></titles><periodical><full-title>Proceedings of the Royal Society of London B: Biological Sciences</full-title></periodical><pages>991-1000</pages><volume>275</volume><number>1638</number><dates><year>2008</year></dates><isbn>0962-8452</isbn><urls></urls></record></Cite><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>10</RecNum><record><rec-number>10</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">10</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly</author><author>Haselton, Martie G</author><author>Fales, Melissa R</author></authors></contributors><titles><title>Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review</title><secondary-title>Psychological Bulletin</secondary-title><alt-title>Psychol Bull</alt-title></titles><periodical><full-title>Psychological Bulletin</full-title></periodical><alt-periodical><abbr-1>Psychol Bull</abbr-1></alt-periodical><pages>1205-1259</pages><volume>140</volume><number>5</number><dates><year>2014</year></dates><isbn>1939-1455</isbn><urls></urls></record></Cite></EndNote>[6,7]. Here, we focus on key findings challenging the view that human ovulation is completely concealed. We also discuss reasons why ovulation cues exist and are so subtle that scientists almost missed them entirely.Typical methodsStudies in this area typically involve within-woman comparisons of high- and low-fertility scents, photos, vocal recordings, and other stimuli. Women who use hormonal contraceptives, which disrupt the cycle, are excluded. It remains common to estimate women’s fertility by counting from their menstrual onset, but the most rigorous studies use hormonal measures.Evidence of Human Ovulation CuesOther-rated attractiveness Evidence across a large variety of species indicates that female scents become more attractive approaching ovulation(see ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2012</Year><RecNum>11</RecNum><DisplayText>[8]</DisplayText><record><rec-number>11</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">11</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly A</author><author>Haselton, Martie G</author><author>Larson, Christina M</author><author>Pillsworth, Elizabeth G</author></authors></contributors><titles><title>Body odor attractiveness as a cue of impending ovulation in women: Evidence from a study using hormone-confirmed ovulation</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>157-166</pages><volume>61</volume><number>2</number><dates><year>2012</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[8]). Likewise, studies have found that women’s natural body scents collected at high fertility (confirmed by luteinizing hormone tests) are rated by men as more attractive and less intense than samples collected at low fertility ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2012</Year><RecNum>11</RecNum><DisplayText>[8]</DisplayText><record><rec-number>11</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">11</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly A</author><author>Haselton, Martie G</author><author>Larson, Christina M</author><author>Pillsworth, Elizabeth G</author></authors></contributors><titles><title>Body odor attractiveness as a cue of impending ovulation in women: Evidence from a study using hormone-confirmed ovulation</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>157-166</pages><volume>61</volume><number>2</number><dates><year>2012</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[8]. Two recent replications showed the same pattern when women rated women’s scent samples ( ADDIN EN.CITE <EndNote><Cite><Author>Woodward</Author><Year>2015</Year><RecNum>32</RecNum><DisplayText>[9]</DisplayText><record><rec-number>32</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">32</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Woodward, Savannah L</author><author>Thompson, Melissa Emery</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses</title><secondary-title>Adaptive Human Behavior and Physiology</secondary-title><alt-title>Adapt Hum Behav Physiol</alt-title></titles><periodical><full-title>Adaptive Human Behavior and Physiology</full-title></periodical><pages>1-15</pages><dates><year>2015</year></dates><isbn>2198-7335</isbn><urls></urls></record></Cite></EndNote>[9]; Gildersleeve, Fales, & Haselton, unpublished data).Women’s facial and vocal attractiveness might also increase as they approach ovulation. In a particularly rigorous study, 202 women provided photos, audio recordings, and saliva samples twice within the cycle ADDIN EN.CITE <EndNote><Cite><Author>Puts</Author><Year>2013</Year><RecNum>13</RecNum><DisplayText>[10]</DisplayText><record><rec-number>13</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">13</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Puts, David A</author><author>Bailey, Drew H</author><author>Cárdenas, Rodrigo A</author><author>Burriss, Robert P</author><author>Welling, Lisa LM</author><author>Wheatley, John R</author><author>Dawood, Khytam</author></authors></contributors><titles><title>Women's attractiveness changes with estradiol and progesterone across the ovulatory cycle</title><secondary-title>Hormones and Behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>13-19</pages><volume>63</volume><number>1</number><dates><year>2013</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[10]. Women’s faces were rated as less attractive when their progesterone was high, consistent with them being at low fertility. In contrast, women’s voices were rated as more attractive when their progesterone was low and estradiol was high, consistent with them being at high fertility (also see ADDIN EN.CITE <EndNote><Cite><Author>Bryant</Author><Year>2009</Year><RecNum>14</RecNum><DisplayText>[11]</DisplayText><record><rec-number>14</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">14</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Bryant, Gregory A</author><author>Haselton, Martie G</author></authors></contributors><titles><title>Vocal cues of ovulation in human females</title><secondary-title>Biology Letters</secondary-title><alt-title>Biol Lett</alt-title></titles><periodical><full-title>Biology Letters</full-title></periodical><pages>12-15</pages><volume>5</volume><number>1</number><dates><year>2009</year></dates><isbn>1744-9561</isbn><urls></urls></record></Cite></EndNote>[11]). Behavioral changesIn many mammalian species, females become more receptive to sexual advances by favored males or even actively solicitous when fertile ADDIN EN.CITE <EndNote><Cite><Author>Beach</Author><Year>1976</Year><RecNum>15</RecNum><DisplayText>[2,12]</DisplayText><record><rec-number>15</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">15</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Beach, Frank A</author></authors></contributors><titles><title>Sexual attractivity, proceptivity, and receptivity in female mammals</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>105-138</pages><volume>7</volume><number>1</number><dates><year>1976</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite><Cite><Author>Dixson</Author><Year>2012</Year><RecNum>4</RecNum><record><rec-number>4</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">4</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Dixson, Alan F</author></authors></contributors><titles><title>Primate Sexuality: Comparative Studies of the Prosimians, Monkeys, Apes, and Humans</title></titles><dates><year>2012</year></dates><publisher>Oxford University Press</publisher><isbn>0191624187</isbn><urls></urls></record></Cite></EndNote>[2,12]. For example, only when fertile do female rats traverse electrified grids to access males (e.g., ADDIN EN.CITE <EndNote><Cite><Author>Meyerson</Author><Year>1973</Year><RecNum>17</RecNum><DisplayText>[13]</DisplayText><record><rec-number>17</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">17</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Meyerson, Bengt J</author><author>Lindstr?m, Leif H</author></authors></contributors><titles><title>Sexual motivation in the female rat. A methodological study applied to the investigation of the effect of estradiol benzoate</title><secondary-title>Acta physiologica Scandinavica. Supplementum</secondary-title><alt-title>Acta Physiol Suppl</alt-title></titles><periodical><full-title>Acta physiologica Scandinavica. Supplementum</full-title></periodical><pages>1</pages><volume>389</volume><dates><year>1973</year></dates><isbn>0302-2994</isbn><urls></urls></record></Cite></EndNote>[13]). Are women more receptive or solicitous when fertile?In two French studies, women approached by an attractive male confederate at high fertility were more likely to consent to a dance ADDIN EN.CITE <EndNote><Cite><Author>Guéguen</Author><Year>2009</Year><RecNum>18</RecNum><DisplayText>[14]</DisplayText><record><rec-number>18</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">18</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Guéguen, Nicolas</author></authors></contributors><titles><title>Menstrual cycle phases and female receptivity to a courtship solicitation: An evaluation in a nightclub</title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><pages>351-355</pages><volume>30</volume><number>5</number><dates><year>2009</year></dates><isbn>1090-5138</isbn><urls></urls></record></Cite></EndNote>[14] and to a request for their phone number ADDIN EN.CITE <EndNote><Cite><Author>Gueguen</Author><Year>2009</Year><RecNum>19</RecNum><DisplayText>[15]</DisplayText><record><rec-number>19</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">19</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gueguen, Nicolas</author></authors></contributors><titles><title>The receptivity of women to courtship solicitation across the menstrual cycle: A field experiment</title><secondary-title>Biological psychology</secondary-title><alt-title>Biol Psychol</alt-title></titles><periodical><full-title>Biological psychology</full-title></periodical><pages>321-324</pages><volume>80</volume><number>3</number><dates><year>2009</year></dates><isbn>0301-0511</isbn><urls></urls></record></Cite></EndNote>[15]. Likewise, women interacting with charismatic male confederates flirted more when fertile ADDIN EN.CITE <EndNote><Cite><Author>Cantú</Author><Year>2013</Year><RecNum>20</RecNum><DisplayText>[16]</DisplayText><record><rec-number>20</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">20</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Cantú, Stephanie M</author><author>Simpson, Jeffry A</author><author>Griskevicius, Vladas</author><author>Weisberg, Yanna J</author><author>Durante, Kristina M</author><author>Beal, Daniel J</author></authors></contributors><titles><title>Fertile and Selectively Flirty: Women’s Behavior Toward Men Changes Across the Ovulatory Cycle</title><secondary-title>Psychological science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>431-438</pages><dates><year>2013</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite></EndNote>[16]. Women might also engage in behaviors that help them distance themselves from undesired partners or individuals who might attempt to influence constrain their mating decisions at high fertility. A study of women’s cell phone records found that women decreased their calls to their fathers, but not to their mothers, when fertile ADDIN EN.CITE <EndNote><Cite><Author>Lieberman</Author><Year>2010</Year><RecNum>21</RecNum><DisplayText>[17]</DisplayText><record><rec-number>21</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">21</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Lieberman, Debra</author><author>Pillsworth, Elizabeth G</author><author>Haselton, Martie G</author></authors></contributors><titles><title>Kin affiliation across the ovulatory cycle females avoid fathers when fertile</title><secondary-title>Psychological science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>13-18</pages><volume>22</volume><number>1</number><dates><year>2010</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite></EndNote>[17].Women might also engage in attractiveness-enhancing behaviors when fertile. In one study, women were videotaped dancing to pop music twice within their cycle. Men rated women’s dance as more attractive at high fertility than at low fertility ADDIN EN.CITE <EndNote><Cite><Author>Fink</Author><Year>2012</Year><RecNum>22</RecNum><DisplayText>[18]</DisplayText><record><rec-number>22</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">22</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Fink, Bernhard</author><author>Hugill, Nadine</author><author>Lange, Benjamin P</author></authors></contributors><titles><title>Women’s body movements are a potential cue to ovulation</title><secondary-title>Personality and Individual Differences</secondary-title><alt-title>Pers Indiv Differ</alt-title></titles><periodical><full-title>Personality and Individual Differences</full-title></periodical><pages>759-763</pages><volume>53</volume><number>6</number><dates><year>2012</year></dates><isbn>0191-8869</isbn><urls></urls></record></Cite></EndNote>[18]. In addition, several studies have shown that women wear more attractive clothing ADDIN EN.CITE <EndNote><Cite><Author>Haselton</Author><Year>2007</Year><RecNum>23</RecNum><DisplayText>[19]</DisplayText><record><rec-number>23</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">23</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Haselton, Martie G</author><author>Mortezaie, Mina</author><author>Pillsworth, Elizabeth G</author><author>Bleske-Rechek, April</author><author>Frederick, David A</author></authors></contributors><titles><title>Ovulatory shifts in human female ornamentation: Near ovulation, women dress to impress</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>40-45</pages><volume>51</volume><number>1</number><dates><year>2007</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[19] and red and pink, specifically, at high fertility ADDIN EN.CITE <EndNote><Cite><Author>Beall</Author><Year>2013</Year><RecNum>24</RecNum><DisplayText>[20,21]</DisplayText><record><rec-number>24</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">24</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Beall, Alec T</author><author>Tracy, Jessica L</author></authors></contributors><titles><title>Women are more likely to wear red or pink at peak fertility</title><secondary-title>Psychological Science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>1837-1841</pages><dates><year>2013</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite><Cite><Author>Prokop</Author><Year>2013</Year><RecNum>25</RecNum><record><rec-number>25</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">25</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Prokop, Pavol</author><author>Hromada, Martin</author></authors></contributors><titles><title>Women use red in order to attract mates</title><secondary-title>Ethology</secondary-title><alt-title>Ethol</alt-title></titles><periodical><full-title>Ethology</full-title></periodical><pages>605-613</pages><volume>119</volume><number>7</number><dates><year>2013</year></dates><isbn>1439-0310</isbn><urls></urls></record></Cite></EndNote>[20,21]. One 35-day study also found that women increased their grooming and styling efforts on fertile days of the cycle ADDIN EN.CITE <EndNote><Cite><Author>Saad</Author><Year>2012</Year><RecNum>26</RecNum><DisplayText>[22]</DisplayText><record><rec-number>26</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">26</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Saad, Gad</author><author>Stenstrom, Eric</author></authors></contributors><titles><title>Calories, beauty, and ovulation: The effects of the menstrual cycle on food and appearance-related consumption</title><secondary-title>Journal of Consumer Psychology</secondary-title><alt-title>J Consum Psychol</alt-title></titles><periodical><full-title>Journal of Consumer Psychology</full-title></periodical><pages>102-113</pages><volume>22</volume><number>1</number><dates><year>2012</year></dates><isbn>1057-7408</isbn><urls></urls></record></Cite></EndNote>[22].Social and hormonal responses in others to women’s ovulation cuesWomen report that their partners are more jealous at high relative to low fertility ADDIN EN.CITE <EndNote><Cite><Author>Haselton</Author><Year>2006</Year><RecNum>27</RecNum><DisplayText>[23,24]</DisplayText><record><rec-number>27</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">27</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Haselton, Martie G</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Conditional expression of women's desires and men's mate guarding across the ovulatory cycle</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>509-518</pages><volume>49</volume><number>4</number><dates><year>2006</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite><Cite><Author>Gangestad</Author><Year>2002</Year><RecNum>28</RecNum><record><rec-number>28</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">28</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Thornhill, Randy</author><author>Garver, Christine E</author></authors></contributors><titles><title>Changes in women's sexual interests and their partner's mate–retention tactics across the menstrual cycle: evidence for shifting conflicts of interest</title><secondary-title>Proceedings of the Royal Society of London B: Biological Sciences</secondary-title><alt-title>Proc R Soc Lond B Biol Sci	</alt-title></titles><periodical><full-title>Proceedings of the Royal Society of London B: Biological Sciences</full-title></periodical><pages>975-982</pages><volume>269</volume><number>1494</number><dates><year>2002</year></dates><isbn>0962-8452</isbn><urls></urls></record></Cite></EndNote>[23,24], suggesting that men might detect changes in their partners across the cycle (e.g., PEVuZE5vdGU+PENpdGU+PEF1dGhvcj5HYW5nZXN0YWQ8L0F1dGhvcj48WWVhcj4yMDE0PC9ZZWFy

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ADDIN EN.CITE.DATA [23-25]).Also, a recent study examined men’s testosterone responses to “rivals” across their partner’s cycle ADDIN EN.CITE <EndNote><Cite><Author>Fales</Author><Year>2014</Year><RecNum>30</RecNum><DisplayText>[26]</DisplayText><record><rec-number>30</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">30</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Fales, Melissa R</author><author>Gildersleeve, Kelly A</author><author>Haselton, Martie G</author></authors></contributors><titles><title>Exposure to perceived male rivals raises men's testosterone on fertile relative to nonfertile days of their partner's ovulatory cycle</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>454-460</pages><volume>65</volume><number>5</number><dates><year>2014</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[26]. Couples completed two sessions, first involving a close interaction to expose the male partner to possible cues of his partner’s fertility. Male partners then viewed profiles of men portrayed as competitive or as non-competitive, whom they were told their partner would rate for attractiveness. Men’s post-test testosterone was higher at high than at low fertility only if they viewed competitive "rivals."In another study, women collected underarm and vulvar scents at high fertility and low fertility ADDIN EN.CITE <EndNote><Cite><Author>Cerda-Molina</Author><Year>2013</Year><RecNum>31</RecNum><DisplayText>[27]</DisplayText><record><rec-number>31</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">31</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Cerda-Molina, Ana Lilia</author><author>Hernández-López, Leonor</author><author>Claudio, E. de la O</author><author>Chavira-Ramírez, Roberto</author><author>Mondragón-Ceballos, Ricardo</author></authors></contributors><titles><title>Changes in men’s salivary testosterone and cortisol levels, and in sexual desire after smelling female axillary and vulvar scents</title><secondary-title>Frontiers in endocrinology</secondary-title><alt-title>Front Endocrin</alt-title></titles><periodical><full-title>Frontiers in endocrinology</full-title></periodical><volume>4</volume><dates><year>2013</year></dates><urls></urls></record></Cite></EndNote>[27]. Men reported their interest in sex and provided saliva samples before and after smelling a high- or low-fertility scent sample. Men exposed to high-fertility scents exhibited increased sexual interest and testosterone thereafter. Men exposed to low-fertility scents exhibited no change in sexual interest and decreased testosterone.A recent study suggests that women also respond hormonally to fertile body scents ADDIN EN.CITE <EndNote><Cite><Author>Woodward</Author><Year>2015</Year><RecNum>32</RecNum><DisplayText>[9]</DisplayText><record><rec-number>32</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">32</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Woodward, Savannah L</author><author>Thompson, Melissa Emery</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses</title><secondary-title>Adaptive Human Behavior and Physiology</secondary-title><alt-title>Adapt Hum Behav Physiol</alt-title></titles><periodical><full-title>Adaptive Human Behavior and Physiology</full-title></periodical><pages>1-15</pages><dates><year>2015</year></dates><isbn>2198-7335</isbn><urls></urls></record></Cite></EndNote>[9]. Women who smelled women’s high-fertility T-shirts displayed higher post-test testosterone than did women who smelled low-fertility T-shirts (marginally significant). This pattern reached significance among women who themselves displayed estrogen and progesterone profiles, consistent with being in the fertile phase of the cycle. Notably, studies examining changes in women’s ADDIN EN.CITE <EndNote><Cite><Author>Maner</Author><Year>2013</Year><RecNum>35</RecNum><DisplayText>[28]</DisplayText><record><rec-number>35</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">35</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Maner, Jon K</author><author>McNulty, James K</author></authors></contributors><titles><title>Attunement to the fertility status of same-sex rivals: women's testosterone responses to olfactory ovulation cues</title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><pages>412-418</pages><volume>34</volume><number>6</number><dates><year>2013</year></dates><isbn>1090-5138</isbn><urls></urls></record></Cite></EndNote>[28] and men’s testosterone ADDIN EN.CITE <EndNote><Cite><Author>Miller</Author><Year>2010</Year><RecNum>36</RecNum><DisplayText>[29]</DisplayText><record><rec-number>36</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">36</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Miller, Saul L.</author><author>Maner, Jon K.</author></authors></contributors><titles><title>Scent of a woman: Men’s testosterone responses to olfactory ovulation cues</title><secondary-title>Psychological Science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>276-283</pages><volume>21</volume><number>2</number><dates><year>2010</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite></EndNote>[29] have often included small numbers of scent samples (from 10 women at most ADDIN EN.CITE <EndNote><Cite><Author>Maner</Author><Year>2013</Year><RecNum>35</RecNum><DisplayText>[28,30]</DisplayText><record><rec-number>35</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">35</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Maner, Jon K</author><author>McNulty, James K</author></authors></contributors><titles><title>Attunement to the fertility status of same-sex rivals: women's testosterone responses to olfactory ovulation cues</title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><pages>412-418</pages><volume>34</volume><number>6</number><dates><year>2013</year></dates><isbn>1090-5138</isbn><urls></urls></record></Cite><Cite><Author>Miller</Author><Year>2011</Year><RecNum>34</RecNum><record><rec-number>34</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">34</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Miller, Saul L</author><author>Maner, Jon K</author></authors></contributors><titles><title>Ovulation as a male mating prime: Subtle signs of women's fertility influence men's mating cognition and behavior</title><secondary-title>Journal of Personality and Social Psychology</secondary-title><alt-title>J Pers Soc Psychol</alt-title></titles><periodical><full-title>Journal of personality and social psychology</full-title></periodical><pages>295-308</pages><volume>100</volume><number>2</number><dates><year>2011</year></dates><isbn>1939-1315</isbn><urls></urls></record></Cite></EndNote>[28,30]), which could vary in attractiveness and other characteristics by chance alone. These studies also have not treated female scent donors as the unit of statistical analysis, thus prohibiting inferences about whether other high- and low-fertility samples would have similar social and hormonal effects (discussed in ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>10</RecNum><DisplayText>[7]</DisplayText><record><rec-number>10</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">10</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly</author><author>Haselton, Martie G</author><author>Fales, Melissa R</author></authors></contributors><titles><title>Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review</title><secondary-title>Psychological Bulletin</secondary-title><alt-title>Psychol Bull</alt-title></titles><periodical><full-title>Psychological Bulletin</full-title></periodical><alt-periodical><abbr-1>Psychol Bull</abbr-1></alt-periodical><pages>1205-1259</pages><volume>140</volume><number>5</number><dates><year>2014</year></dates><isbn>1939-1455</isbn><urls></urls></record></Cite></EndNote>[7]).Ovulation cues: Effect sizes and robustnessIn sum, many findings are consistent with the existence of detectable ovulation cues. Effect sizes have typically ranged from small to medium, though these estimates could be conservative given error in measuring women’s fertility within the cycle ADDIN EN.CITE <EndNote><Cite><Author>Cohen</Author><Year>1988</Year><RecNum>37</RecNum><DisplayText>[31,32]</DisplayText><record><rec-number>37</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">37</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Cohen, Jacob</author></authors></contributors><titles><title>Statistical power analysis for the behavioral sciences</title></titles><dates><year>1988</year></dates><pub-location>Hillsdale, N.J.</pub-location><publisher>L. Erlbaum Associates</publisher><isbn>9780805802832 0805802835</isbn><urls></urls><remote-database-name>/z-wcorg/</remote-database-name><remote-database-provider> press</Year><RecNum>52</RecNum><record><rec-number>52</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">52</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Haselton, Martie G</author><author>Welling, Lisa M</author><author>Gildersleeve, Kelly A</author><author>Pillsworth, Elizabeth G</author><author>Burriss, Robert P</author><author>Larson, Christina M</author><author>Puts, David A</author></authors></contributors><titles><title>How valid are assessments of conception probability in ovulatory cycle research? Evaluations, recommended standards, and theoretical implications. </title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><dates><year>in press</year></dates><urls></urls></record></Cite></EndNote>[31,32]. (Here, we report effect sizes in Hedges’s g, which is interpreted identically to Cohen’s d but is less biased ADDIN EN.CITE <EndNote><Cite><Author>Borenstein</Author><Year>2009</Year><RecNum>38</RecNum><DisplayText>[33]</DisplayText><record><rec-number>38</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">38</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Borenstein, Michael</author></authors></contributors><titles><title>Introduction to meta-analysis</title></titles><dates><year>2009</year></dates><pub-location>Chichester, U.K.</pub-location><publisher>John Wiley & Sons</publisher><isbn>9780470057247 0470057246</isbn><urls></urls><remote-database-name>/z-wcorg/</remote-database-name><remote-database-provider>;[33].) For example, the high-fertility increase in women’s flirtation with a charismatic confederate is about a third of a standard deviation (0.31 ADDIN EN.CITE <EndNote><Cite><Author>Cantú</Author><Year>2013</Year><RecNum>20</RecNum><DisplayText>[16]</DisplayText><record><rec-number>20</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">20</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Cantú, Stephanie M</author><author>Simpson, Jeffry A</author><author>Griskevicius, Vladas</author><author>Weisberg, Yanna J</author><author>Durante, Kristina M</author><author>Beal, Daniel J</author></authors></contributors><titles><title>Fertile and Selectively Flirty: Women’s Behavior Toward Men Changes Across the Ovulatory Cycle</title><secondary-title>Psychological science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>431-438</pages><dates><year>2013</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite></EndNote>[16]). The increase in women’s scent attractiveness is about half of a standard deviation (g = .55 ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2015</Year><RecNum>12</RecNum><DisplayText>[34]</DisplayText><record><rec-number>12</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">12</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly A.; Fales, Melissa R.; Haselton, Martie G.</author></authors></contributors><titles><title>Stopping to Smell Rosie: Women's Evaluations of Other Women’s Body Odor Depend on Targets’ Fertility and Hormonal Contraception Use </title><secondary-title>Unpublished</secondary-title></titles><periodical><full-title>Unpublished</full-title></periodical><dates><year>2015</year></dates><urls></urls></record></Cite></EndNote>[34]). The increase in men’s testosterone in response to fertile scents is apparently larger, at just under half of a standard deviation to two standard deviations (g = .42 to 2.04 ADDIN EN.CITE <EndNote><Cite><Author>Cerda-Molina</Author><Year>2013</Year><RecNum>31</RecNum><DisplayText>[27]</DisplayText><record><rec-number>31</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">31</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Cerda-Molina, Ana Lilia</author><author>Hernández-López, Leonor</author><author>Claudio, E. de la O</author><author>Chavira-Ramírez, Roberto</author><author>Mondragón-Ceballos, Ricardo</author></authors></contributors><titles><title>Changes in men’s salivary testosterone and cortisol levels, and in sexual desire after smelling female axillary and vulvar scents</title><secondary-title>Frontiers in endocrinology</secondary-title><alt-title>Front Endocrin</alt-title></titles><periodical><full-title>Frontiers in endocrinology</full-title></periodical><volume>4</volume><dates><year>2013</year></dates><urls></urls></record></Cite></EndNote>[27]). However, there are some notable non-replications of key findings (e.g., in men’s testosterone in response to fertile body scents ADDIN EN.CITE <EndNote><Cite><Author>Roney</Author><Year>2012</Year><RecNum>39</RecNum><DisplayText>[35]</DisplayText><record><rec-number>39</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">39</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Roney, James R</author><author>Simmons, Zachary L</author></authors></contributors><titles><title>Men smelling women: null effects of exposure to ovulatory sweat on men’s testosterone</title><secondary-title>Evolutionary Psychology</secondary-title><alt-title>Evol Psychol</alt-title></titles><periodical><full-title>Evolutionary Psychology</full-title></periodical><pages>703-713</pages><volume>10</volume><number>4</number><dates><year>2012</year></dates><isbn>1474-7049</isbn><urls></urls></record></Cite></EndNote>[35]). A meta-analysis including these non-replications and additional unpublished data indicates that overall effects are nonetheless statistically robust ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>40</RecNum><DisplayText>[36]</DisplayText><record><rec-number>40</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">40</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly A.</author></authors></contributors><titles><title>Meta-analytic and Experimental Investigations of Shifts in Women’s Mate Preferences and Attractiveness across the Ovulatory Cycle</title><secondary-title>Unpublished Dissertation</secondary-title></titles><periodical><full-title>Unpublished Dissertation</full-title></periodical><dates><year>2014</year></dates><urls></urls></record></Cite></EndNote>[36]. Thus, ovulation cues are likely subtler in humans than in many other mammals but probably still have meaningful social consequences.Why do Human Ovulation Cues Exist?What evolved function, if any, have ovulation cues historically served for women? One possibility is that evolutionary forces favored ovulation cues in women to signal their fertility to men, thus promoting mating and conception. This seems unlikely, however, given high levels of sexual interest among men (see ADDIN EN.CITE <EndNote><Cite><Author>Thornhill</Author><Year>2008</Year><RecNum>41</RecNum><DisplayText>[37]</DisplayText><record><rec-number>41</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite></EndNote>[37] for an extended discussion). We think the opposite is more plausible (see Box 1). Evolution might have favored the concealment of ovulation to reduce unwanted male sexual advances or aggression from other females, while encouraging current mates to invest throughout the cycle. Along these lines, the leaky cues hypothesis proposes that cues of ovulation are incidental byproducts of physiological changes that trigger ovulation ADDIN EN.CITE <EndNote><Cite><Author>Haselton</Author><Year>2011</Year><RecNum>1</RecNum><DisplayText>[37,38]</DisplayText><record><rec-number>1</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">1</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Haselton, Martie G.</author><author>Gildersleeve, Kelly</author></authors></contributors><titles><title>Can Men Detect Ovulation?</title><secondary-title>Current Directions in Psychological Science</secondary-title><alt-title>Cur Dir Psychol Sci</alt-title></titles><periodical><full-title>Current Directions in Psychological Science</full-title></periodical><pages>87-92</pages><volume>20</volume><number>2</number><dates><year>2011</year><pub-dates><date>April 1, 2011</date></pub-dates></dates><urls><related-urls><url> app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite></EndNote>[37,38], which women’s bodies cannot fully conceal without compromising fertility. Once ovulation cues—however subtle—are “leaked” from the system, evolution can favor a male ability to detect them. Another possibility is that women have evolved to signal their overall reproductive quality in order to attract desirable long-term mates ADDIN EN.CITE <EndNote><Cite><Author>Pagel</Author><Year>1994</Year><RecNum>42</RecNum><DisplayText>[39]</DisplayText><record><rec-number>42</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">42</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Pagel, Mark</author></authors></contributors><titles><title>The evolution of conspicuous oestrous advertisement in Old World monkeys</title><secondary-title>Animal Behaviour</secondary-title><alt-title>Anim Behav</alt-title></titles><periodical><full-title>Animal Behaviour</full-title></periodical><pages>1333-1341</pages><volume>47</volume><number>6</number><dates><year>1994</year></dates><isbn>0003-3472</isbn><urls></urls></record></Cite></EndNote>[39]. Estradiol levels could indicate overall reproductive quality and also vary across the cycle, peaking just prior to ovulation. Therefore, any estradiol-dependent signals of overall reproductive quality will incidentally increase at high fertility. Thus, cues of ovulation are still “leaked” but within the context of constant signaling of overall reproductive quality.Notably, these explanations best account for shifts in women’s physical attractiveness (e.g., scent). Shifts in women’s receptivity and solicitousness might instead reflect shifts in women’s mating motivations (see ADDIN EN.CITE <EndNote><Cite><Author>Gangestad</Author><Year>2015</Year><RecNum>43</RecNum><DisplayText>[7,40]</DisplayText><record><rec-number>43</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">43</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Haselton, Martie G</author></authors></contributors><titles><title>Human estrus: implications for relationship science</title><secondary-title>Current Opinions in Psychology</secondary-title><alt-title>Curr Opin Psychol</alt-title></titles><periodical><full-title>Current Opinions in Psychology</full-title><abbr-1>Curr Opin Psychol</abbr-1></periodical><alt-periodical><full-title>Current Opinions in Psychology</full-title><abbr-1>Curr Opin Psychol</abbr-1></alt-periodical><pages>45-51</pages><volume>1</volume><dates><year>2015</year></dates><isbn>2352-250X</isbn><urls></urls></record></Cite><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>10</RecNum><record><rec-number>10</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">10</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly</author><author>Haselton, Martie G</author><author>Fales, Melissa R</author></authors></contributors><titles><title>Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review</title><secondary-title>Psychological Bulletin</secondary-title><alt-title>Psychol Bull</alt-title></titles><periodical><full-title>Psychological Bulletin</full-title></periodical><alt-periodical><abbr-1>Psychol Bull</abbr-1></alt-periodical><pages>1205-1259</pages><volume>140</volume><number>5</number><dates><year>2014</year></dates><isbn>1939-1455</isbn><urls></urls></record></Cite></EndNote>[7,40]).ConclusionThe studies we have reviewed overturn the conventional wisdom that human sexuality is vastly different from that of other mammals. Women also appear to experience high-fertility increases in their attractiveness, receptiveness, and solicitousness, though these changes have likely been modified during human evolution ADDIN EN.CITE <EndNote><Cite><Author>Thornhill</Author><Year>2008</Year><RecNum>41</RecNum><DisplayText>[37]</DisplayText><record><rec-number>41</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite></EndNote>[37]. We encourage theoretical and empirical work to better understand the evolutionary origins—and possible social consequences—of these cycle shifts (see Table 1). Such work will refine and add nuance to our understanding of human sexuality, relationship dynamics, and aspects of human evolution that unite and differentiate us from other species.Box 1 -- Why are Human Ovulation Cues Subtle?Human ovulation cues appear to be present but subtle. For example, scent cues of ovulation in humans, though they appear to exist, are not likely to be discernable by males across vast distances, as they are in other primate species ADDIN EN.CITE <EndNote><Cite><Author>Thornhill</Author><Year>2008</Year><RecNum>41</RecNum><DisplayText>[37]</DisplayText><record><rec-number>41</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite></EndNote>[37]. This raises the question, why? Increasing paternal investmentConcealing clear cues of ovulation might have facilitated the evolution of human pair bonding and biparental childrearing. If female ovulation is non-obvious, male partners must be near their partner throughout the cycle to be certain of their genetic relation to their children ADDIN EN.CITE <EndNote><Cite><Author>Noonan</Author><Year>1979</Year><RecNum>45</RecNum><DisplayText>[5,41]</DisplayText><record><rec-number>45</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">45</key></foreign-keys><ref-type name="Book Section">5</ref-type><contributors><authors><author>Alexander, R.</author><author>Noonan, K. M.</author></authors><secondary-authors><author>Chagnon, N.</author><author>Irons, W.</author></secondary-authors></contributors><titles><title>Concealment of ovulation, parental care, and human social evolution</title><secondary-title>Evolutionary Biology and Human Social Behavior: An Anthropological Perspective.</secondary-title></titles><pages>436-453</pages><dates><year>1979</year></dates><pub-location>North Scituate, MA</pub-location><publisher>Duxbury Press</publisher><urls></urls></record></Cite><Cite><Author>Symons</Author><Year>1979</Year><RecNum>6</RecNum><record><rec-number>6</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">6</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Symons, Donald</author></authors></contributors><titles><title>The evolution of human sexuality</title></titles><dates><year>1979</year></dates><pub-location>New York</pub-location><publisher>Oxford University Press</publisher><isbn>0195025350 9780195025354</isbn><urls></urls><remote-database-name>/z-wcorg/</remote-database-name><remote-database-provider>;[5,41]. In turn, increased paternity certainty increases the benefits to men of investing in their partner and children, further reinforcing pair bonding. Related to this idea, the extended sexuality hypothesis proposes that women have evolved to have sex throughout the cycle (rather than in the fertile window alone) in order to promote paternal investment ADDIN EN.CITE <EndNote><Cite><Author>Grebe</Author><Year>2013</Year><RecNum>7</RecNum><DisplayText>[42]</DisplayText><record><rec-number>7</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">7</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Grebe, Nicholas M</author><author>Gangestad, Steven W</author><author>Garver-Apgar, Christine E</author><author>Thornhill, Randy</author></authors></contributors><titles><title>Women’s luteal-phase sexual proceptivity and the functions of extended sexuality</title><secondary-title>Psychological science</secondary-title><alt-title>Psychol Sci</alt-title></titles><periodical><full-title>Psychological science</full-title></periodical><pages>2106-2110</pages><volume>24</volume><number>10</number><dates><year>2013</year></dates><isbn>0956-7976</isbn><urls></urls></record></Cite></EndNote>[42]. Relatedly, if ovulation were obvious, socially dominant males could have attempted to monopolize mating opportunities with fertile females. However, non-dominant males might offer benefits to women, such as investment in their children. Therefore, the concealment of cues of ovulation might have enabled women to pursue non-dominant males ADDIN EN.CITE <EndNote><Cite><Author>Strassmann</Author><Year>1981</Year><RecNum>47</RecNum><DisplayText>[43]</DisplayText><record><rec-number>47</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">47</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Strassmann, Beverly I</author></authors></contributors><titles><title>Sexual selection, paternal care, and concealed ovulation in humans</title><secondary-title>Ethology and Sociobiology</secondary-title><alt-title>Ethol Sociobiol</alt-title></titles><periodical><full-title>Ethology and Sociobiology</full-title></periodical><pages>31-40</pages><volume>2</volume><number>1</number><dates><year>1981</year></dates><isbn>0162-3095</isbn><urls></urls></record></Cite></EndNote>[43]. In turn, increased male investment could help to explain a variety of notable human features, such as heavily dependent young, short inter-birth intervals, and large family sizes (reviewed in ADDIN EN.CITE <EndNote><Cite><Author>Pillsworth</Author><Year>2006</Year><RecNum>48</RecNum><DisplayText>[44]</DisplayText><record><rec-number>48</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">48</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Pillsworth, Elizabeth G</author><author>Haselton, Martie G</author></authors></contributors><titles><title>Women's sexual strategies: The evolution of long-term bonds and extrapair sex</title><secondary-title>Annual Review of Sex Research</secondary-title><alt-title>Annu Rev Sex Res</alt-title></titles><periodical><full-title>Annual Review of Sex Research</full-title></periodical><pages>59-100</pages><volume>17</volume><number>1</number><dates><year>2006</year></dates><isbn>1053-2528</isbn><urls></urls></record></Cite></EndNote>[44]).Preserving female choiceCurrent male partners cannot mate guard constantly and therefore may benefit by guarding their female partner primarily during her fertile period (when a failure to do so could result in her conceiving with another male). Thus, the concealment of cues of ovulation might have enhanced females’ freedom to choose the genetic fathers of their offspring ADDIN EN.CITE <EndNote><Cite><Author>Thornhill</Author><Year>2008</Year><RecNum>41</RecNum><DisplayText>[37,38]</DisplayText><record><rec-number>41</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite><Cite><Author>Haselton</Author><Year>2011</Year><RecNum>3</RecNum><record><rec-number>3</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">3</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Haselton, Martie G.</author><author>Gildersleeve, Kelly</author></authors></contributors><titles><title>Can Men Detect Ovulation?</title><secondary-title>Current Directions in Psychological Science</secondary-title><alt-title>Curr Dir Psychol Sci</alt-title></titles><periodical><full-title>Current Directions in Psychological Science</full-title></periodical><pages>87-92</pages><volume>20</volume><number>2</number><dates><year>2011</year><pub-dates><date>April 1, 2011</date></pub-dates></dates><urls><related-urls><url>;[37,38]. For example, some human females might historically have reproductively benefitted by pursuing a “mixed” mating strategy, securing investment from long-term partners but acquiring genetic benefits from surreptitious sexual affairs with other men at high fertility ADDIN EN.CITE <EndNote><Cite><Author>Thornhill</Author><Year>2008</Year><RecNum>41</RecNum><DisplayText>[7,37]</DisplayText><record><rec-number>41</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">41</key></foreign-keys><ref-type name="Book">6</ref-type><contributors><authors><author>Thornhill, Randy</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>The evolutionary biology of human female sexuality</title></titles><dates><year>2008</year></dates><publisher>Oxford University Press</publisher><isbn>0199887705</isbn><urls></urls></record></Cite><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>10</RecNum><record><rec-number>10</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">10</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly</author><author>Haselton, Martie G</author><author>Fales, Melissa R</author></authors></contributors><titles><title>Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review</title><secondary-title>Psychological Bulletin</secondary-title><alt-title>Psychol Bull</alt-title></titles><periodical><full-title>Psychological Bulletin</full-title></periodical><alt-periodical><abbr-1>Psychol Bull</abbr-1></alt-periodical><pages>1205-1259</pages><volume>140</volume><number>5</number><dates><year>2014</year></dates><isbn>1939-1455</isbn><urls></urls></record></Cite></EndNote>[7,37]. Avoiding aggression from other femalesLastly, concealing ovulation cues might have helped women avoid aggression from other women. A recent study of chacma baboons demonstrated that females were most likely to become the target of female-female aggression—which can be deadly—when displaying sexual swellings and receiving attention from a male ADDIN EN.CITE <EndNote><Cite><Author>Huchard</Author><Year>2011</Year><RecNum>44</RecNum><DisplayText>[45]</DisplayText><record><rec-number>44</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">44</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Huchard, Elise</author><author>Cowlishaw, Guy</author></authors></contributors><titles><title>Female–female aggression around mating: an extra cost of sociality in a multimale primate society</title><secondary-title>Behavioral Ecology</secondary-title><alt-title>Behav Ecol</alt-title></titles><periodical><full-title>Behavioral Ecology</full-title></periodical><pages>arr083</pages><dates><year>2011</year></dates><isbn>1045-2249</isbn><urls></urls></record></Cite></EndNote>[45]. In humans, women rate other women’s high-fertility body odors as more attractive than their low-fertility odors ( ADDIN EN.CITE <EndNote><Cite><Author>Woodward</Author><Year>2015</Year><RecNum>32</RecNum><DisplayText>[9]</DisplayText><record><rec-number>32</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">32</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Woodward, Savannah L</author><author>Thompson, Melissa Emery</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses</title><secondary-title>Adaptive Human Behavior and Physiology</secondary-title><alt-title>Adapt Hum Behav Physiol</alt-title></titles><periodical><full-title>Adaptive Human Behavior and Physiology</full-title></periodical><pages>1-15</pages><dates><year>2015</year></dates><isbn>2198-7335</isbn><urls></urls></record></Cite></EndNote>[9]; Gildersleeve et al., unpublished data) and appear to experience increased testosterone in response to fertile body odors ADDIN EN.CITE <EndNote><Cite><Author>Maner</Author><Year>2013</Year><RecNum>35</RecNum><DisplayText>[28]</DisplayText><record><rec-number>35</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">35</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Maner, Jon K</author><author>McNulty, James K</author></authors></contributors><titles><title>Attunement to the fertility status of same-sex rivals: women's testosterone responses to olfactory ovulation cues</title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><pages>412-418</pages><volume>34</volume><number>6</number><dates><year>2013</year></dates><isbn>1090-5138</isbn><urls></urls></record></Cite></EndNote>[28], though perhaps only when fertile themselves ADDIN EN.CITE <EndNote><Cite><Author>Woodward</Author><Year>2015</Year><RecNum>32</RecNum><DisplayText>[9]</DisplayText><record><rec-number>32</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">32</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Woodward, Savannah L</author><author>Thompson, Melissa Emery</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses</title><secondary-title>Adaptive Human Behavior and Physiology</secondary-title><alt-title>Adapt Hum Behav Physiol</alt-title></titles><periodical><full-title>Adaptive Human Behavior and Physiology</full-title></periodical><pages>1-15</pages><dates><year>2015</year></dates><isbn>2198-7335</isbn><urls></urls></record></Cite></EndNote>[9]. This could facilitate aggression, though evidence to date is inconclusive ADDIN EN.CITE <EndNote><Cite><Author>Woodward</Author><Year>2015</Year><RecNum>32</RecNum><DisplayText>[9]</DisplayText><record><rec-number>32</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">32</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Woodward, Savannah L</author><author>Thompson, Melissa Emery</author><author>Gangestad, Steven W</author></authors></contributors><titles><title>Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses</title><secondary-title>Adaptive Human Behavior and Physiology</secondary-title><alt-title>Adapt Hum Behav Physiol</alt-title></titles><periodical><full-title>Adaptive Human Behavior and Physiology</full-title></periodical><pages>1-15</pages><dates><year>2015</year></dates><isbn>2198-7335</isbn><urls></urls></record></Cite></EndNote>[9]. Moreover, aggression against fertile females might be most pronounced in species exhibiting clear visual fertility cues (e.g., swellings).Table 1: Future Research Directions Unresolved IssuesSuggestion for Future WorkMethods. (1) Studies of subtle ovulation cues require sufficient power. (2) Research designs that imprecisely estimate fertility within the cycle cannot speak to the true magnitude of ovulation cues (see ADDIN EN.CITE <EndNote><Cite><Author>Gangestad</Author><Year>in press</Year><RecNum>52</RecNum><DisplayText>[32]</DisplayText><record><rec-number>52</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">52</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Haselton, Martie G</author><author>Welling, Lisa M</author><author>Gildersleeve, Kelly A</author><author>Pillsworth, Elizabeth G</author><author>Burriss, Robert P</author><author>Larson, Christina M</author><author>Puts, David A</author></authors></contributors><titles><title>How valid are assessments of conception probability in ovulatory cycle research? Evaluations, recommended standards, and theoretical implications. </title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><dates><year>in press</year></dates><urls></urls></record></Cite></EndNote>[32]); (3) methods have been highly variable, prompting criticism that flexibility in analytic procedures has increased the false positive rate (see ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2014</Year><RecNum>49</RecNum><DisplayText>[46]</DisplayText><record><rec-number>49</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">49</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly</author><author>Haselton, Martie G</author><author>Fales, Melissa R</author></authors></contributors><titles><title>Meta-analyses and p-curves support robust cycle shifts in women’s mate preferences: Reply to Wood and Carden (2014) and Harris, Pashler, and Mickes (2014)</title><secondary-title>Psychological Bulletin</secondary-title><alt-title>Psychol Bull</alt-title></titles><periodical><full-title>Psychological Bulletin</full-title></periodical><alt-periodical><abbr-1>Psychol Bull</abbr-1></alt-periodical><pages>1272-1280</pages><dates><year>2014</year></dates><isbn>1939-1455</isbn><urls></urls></record></Cite></EndNote>[46]). (1 & 2) Conduct within-women studies to detect subtle cycle shifts. Ideally, include hormonal confirmation (e.g., LH tests) or concrete benchmarks of cycle position (e.g., prospectively assessed menstrual onset; see ADDIN EN.CITE <EndNote><Cite><Author>Gangestad</Author><Year>in press</Year><RecNum>52</RecNum><DisplayText>[32]</DisplayText><record><rec-number>52</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">52</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gangestad, Steven W</author><author>Haselton, Martie G</author><author>Welling, Lisa M</author><author>Gildersleeve, Kelly A</author><author>Pillsworth, Elizabeth G</author><author>Burriss, Robert P</author><author>Larson, Christina M</author><author>Puts, David A</author></authors></contributors><titles><title>How valid are assessments of conception probability in ovulatory cycle research? Evaluations, recommended standards, and theoretical implications. </title><secondary-title>Evolution and Human Behavior</secondary-title><alt-title>Evol Hum Behav</alt-title></titles><periodical><full-title>Evolution and Human Behavior</full-title></periodical><dates><year>in press</year></dates><urls></urls></record></Cite></EndNote>[32] for details, including recommended Ns based on power analyses). Conduct analyses that treat cycling women (rather than responders) as the unit of statistical analysis to justify inferences about the general magnitude of ovulation cues or their effects on others (see ADDIN EN.CITE <EndNote><Cite><Author>Gildersleeve</Author><Year>2012</Year><RecNum>11</RecNum><DisplayText>[8]</DisplayText><record><rec-number>11</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">11</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Gildersleeve, Kelly A</author><author>Haselton, Martie G</author><author>Larson, Christina M</author><author>Pillsworth, Elizabeth G</author></authors></contributors><titles><title>Body odor attractiveness as a cue of impending ovulation in women: Evidence from a study using hormone-confirmed ovulation</title><secondary-title>Hormones and behavior</secondary-title><alt-title>Horm Behav</alt-title></titles><periodical><full-title>Hormones and behavior</full-title></periodical><pages>157-166</pages><volume>61</volume><number>2</number><dates><year>2012</year></dates><isbn>0018-506X</isbn><urls></urls></record></Cite></EndNote>[8]). (3) Work to achieve agreed-upon methodological standards to facilitate cross-study comparisons and avoid “false positive” criticisms.Hormonal mediators. Few studies have examined specific hormonal mediators of ovulation cues. Hormonal mediators can help to adjudicate between alternative explanations for the existence of ovulation cues and unite the human and non-human literatures.Assay hormones, preferably at multiple times across the cycle.Effects of hormonal contraceptives (HCs). (1) HCs appear to eliminate changes in women’s attractiveness and social behavior across the cycle ADDIN EN.CITE <EndNote><Cite><Author>Alvergne</Author><Year>2010</Year><RecNum>50</RecNum><DisplayText>[47]</DisplayText><record><rec-number>50</rec-number><foreign-keys><key app="EN" db-id="s0dxxatr3dr09oesv5b5xfvlptdf0xtxz2te">50</key></foreign-keys><ref-type name="Journal Article">17</ref-type><contributors><authors><author>Alvergne, Alexandra</author><author>Lummaa, Virpi</author></authors></contributors><titles><title>Does the contraceptive pill alter mate choice in humans?</title><secondary-title>Trends in Ecology & Evolution</secondary-title><alt-title>Trends Ecol Evol</alt-title></titles><periodical><full-title>Trends in Ecology & Evolution</full-title></periodical><pages>171-179</pages><volume>25</volume><number>3</number><dates><year>2010</year></dates><isbn>0169-5347</isbn><urls></urls></record></Cite></EndNote>[47]. However, the effects of HCs on overall attractiveness, receptivity, solicitousness, and relationship dynamics are largely unknown, despite potentially important consequences for women’s well-being. (2) HC use is often confounded with other factors, such as relationship status. (3) Moreover, HCs differ in dosage and form of estrogen and progestin and dosage schedule. Different formulations could have different effects.(1) Compare naturally-cycling and HC-using women both across the cycle and overall, ideally, through randomized controlled trials. (2) Account for possible confounds (see Christina M Larson, PhD dissertation, UCLA, 2014). (3) Examine effects of different HC formulations (Grebe et al., unpublished data).How do men versus women respond to ovulation cues? Few studies have examined women’s responses to ovulation cues in other women. It remains unknown whether women increase their competitive responses to women who are in the fertile pare men’s and women’s responses to high- and low-fertility stimuli, and test between competing explanations for women’s ability to detect ovulation cues.Ovulation cues in the wild. Most studies isolate putative ovulation cues and study their effects on unacquainted individuals in the laboratory. The effects in women’s ongoing relationships – both with women and men – is unknown. Conduct studies examining changes across the cycle in romantic partner’s perceptions of women’s attractiveness, receptivity, and solicitousness; in their responses to their partner; in their hormones; and so on. AcknowledgementsWe thank Steve Gangestad for discussion of the ideas contained in this manuscript. References ADDIN EN.REFLIST 1. Nelson RJ: An introduction to behavioral endocrinology: Sinauer Associates; 2005.2. Dixson AF: Primate Sexuality: Comparative Studies of the Prosimians, Monkeys, Apes, and Humans: Oxford University Press; 2012.3. Nadler R, Graham C, Collins D, Gould K: Plasma Gonadotropins, Prolactin, Gonadal Steroids, and Genital Swelling during the Menstrual Cycle of Lowland Gorillas*. Endocrin 1979, 105:290-296.4. Alberts SC, Buchan J, Almann J: Sexual selection in wild baboons: From mating opportunities to paternity success. Anim Behav 2006, 71:1177-1196.5. Symons D: The evolution of human sexuality. New York: Oxford University Press; 1979.6. Gangestad SW, Thornhill R: Human oestrus. Proc R Soc Lond B Biol Sci 2008, 275:991-1000.**7. Gildersleeve K, Haselton MG, Fales MR: Do women’s mate preferences change across the ovulatory cycle? A meta-analytic review. Psychol Bull 2014, 140:1205-1259.This meta-analysis evaluated evidence for shifts across the ovulatory cycle in women’s mate preferences. Results showed that women prefer purported indicators of genetic quality (e.g., body masculinity) more on fertile than non-fertile days of the cycle. These shifts were present when women evaluated men’s short-term sexual desirability or attractiveness but absent when they evaluated men’s long-term desirability. These results remained statistically significant after adjusting for possible publication bias.*8. Gildersleeve KA, Haselton MG, Larson CM, Pillsworth EG: Body odor attractiveness as a cue of impending ovulation in women: Evidence from a study using hormone-confirmed ovulation. Horm Behav 2012, 61:157-166.In this lab study, men rated samples of women's natural body odor collected at high- and low-fertility points within the ovulatory cycle (confirmed by luteinizing hormone tests). Men rated women's high- fertility body odor as sexier and more pleasant but slightly less intense than their low-fertility body odor.9. Woodward SL, Thompson ME, Gangestad SW: Women Exposed to the Scents of Fertile-Phase and Luteal-Phase Women: Evaluative, Competitive, and Endocrine Responses. Adapt Hum Behav Physiol 2015:1-15.**10. Puts DA, Bailey DH, Cárdenas RA, Burriss RP, Welling LL, Wheatley JR, Dawood K: Women's attractiveness changes with estradiol and progesterone across the ovulatory cycle. Horm Behav 2013, 63:13-19.In this study, women provided vocal recordings, facial photos, and hormone samples twice within their cycles--when their estradiol and progesterone were at their respective peaks. Men rated both women's photos and vocal recordings as more attractive when their progesterone was low, consistent with them being in the follicular phase. Also, men rated women's vocal recordings as more attractive when their progesterone was low but estradiol was high, consistent with them being in the late follicular phase, when fertility is maximal.11. Bryant GA, Haselton MG: Vocal cues of ovulation in human females. Biol Lett 2009, 5:12-15.12. Beach FA: Sexual attractivity, proceptivity, and receptivity in female mammals. Horm Behav 1976, 7:105-138.13. Meyerson BJ, Lindstr?m LH: Sexual motivation in the female rat. A methodological study applied to the investigation of the effect of estradiol benzoate. Acta Physiol Suppl 1973, 389:1.14. Guéguen N: Menstrual cycle phases and female receptivity to a courtship solicitation: An evaluation in a nightclub. Evol Hum Behav 2009, 30:351-355.15. Gueguen N: The receptivity of women to courtship solicitation across the menstrual cycle: A field experiment. Biol Psychol 2009, 80:321-324.*16. Cantú SM, Simpson JA, Griskevicius V, Weisberg YJ, Durante KM, Beal DJ: Fertile and Selectively Flirty: Women’s Behavior Toward Men Changes Across the Ovulatory Cycle. Psychol Sci 2013:431-438.In this experiment, women interacted with confident and sexy (but unreliable) “cads” and kind and caring (but uncharismatic) “dads” at high and low fertility within the cycle, as confirmed by luteinizing hormone tests. Women were more flirtatious with the “cads” than with the “dads” only at high fertility; no such difference was observed at low fertility. 17. Lieberman D, Pillsworth EG, Haselton MG: Kin affiliation across the ovulatory cycle females avoid fathers when fertile. Psychol Sci 2010, 22:13-18.18. Fink B, Hugill N, Lange BP: Women’s body movements are a potential cue to ovulation. Pers Indiv Differ 2012, 53:759-763.19. Haselton MG, Mortezaie M, Pillsworth EG, Bleske-Rechek A, Frederick DA: Ovulatory shifts in human female ornamentation: Near ovulation, women dress to impress. Horm Behav 2007, 51:40-45.20. Beall AT, Tracy JL: Women are more likely to wear red or pink at peak fertility. Psychol Sci 2013:1837-1841.21. Prokop P, Hromada M: Women use red in order to attract mates. Ethol 2013, 119:605-613.22. Saad G, Stenstrom E: Calories, beauty, and ovulation: The effects of the menstrual cycle on food and appearance-related consumption. J Consum Psychol 2012, 22:102-113.23. Haselton MG, Gangestad SW: Conditional expression of women's desires and men's mate guarding across the ovulatory cycle. Horm Behav 2006, 49:509-518.24. Gangestad SW, Thornhill R, Garver CE: Changes in women's sexual interests and their partner's mate–retention tactics across the menstrual cycle: evidence for shifting conflicts of interest. Proc R Soc Lond B Biol Sci 2002, 269:975-982.25. Gangestad SW, Garver-Apgar CE, Cousins AJ, Thornhill R: Intersexual conflict across women's ovulatory cycle. Evol Hum Behav 2014, 35:302-308.**26. Fales MR, Gildersleeve KA, Haselton MG: Exposure to perceived male rivals raises men's testosterone on fertile relative to nonfertile days of their partner's ovulatory cycle. Horm Behav 2014, 65:454-460.In this study, romantic couples completed lab sessions at high and low fertility within the female partner’s cycle. At both sessions, the couple completed an interaction to expose the male partner to possible ovulation cues in his female partner. The male partner then viewed profiles of putative male rivals portrayed as either highly competitive or non-competitive. Men exposed to highly competitive rivals exhibited a greater testosterone response to the manipulation at high than at low fertility, whereas men exposed to non-competitive rivals showed no such pattern.*27. Cerda-Molina AL, Hernández-López L, Claudio EdlO, Chavira-Ramírez R, Mondragón-Ceballos R: Changes in men’s salivary testosterone and cortisol levels, and in sexual desire after smelling female axillary and vulvar scents. Front Endocrin 2013, 4.In this study, researchers used a nebulizer to expose men to underarm and vulvar odors collected from women in the high-fertility phase or in the low-fertility premenstrual phase (verified by estradiol and progesterone assays). Exposure to women’s fertile underarm and vulvar odors increased men’s testosterone and interest in sex, whereas exposure to premenstrual underarm and vulvar odors decreased men’s testosterone and had no effect on their interest in sex.28. Maner JK, McNulty JK: Attunement to the fertility status of same-sex rivals: women's testosterone responses to olfactory ovulation cues. Evol Hum Behav 2013, 34:412-418.29. Miller SL, Maner JK: Scent of a woman: Men’s testosterone responses to olfactory ovulation cues. Psychol Sci 2010, 21:276-283.30. Miller SL, Maner JK: Ovulation as a male mating prime: Subtle signs of women's fertility influence men's mating cognition and behavior. J Pers Soc Psychol 2011, 100:295-308.31. Cohen J: Statistical power analysis for the behavioral sciences. Hillsdale, N.J.: L. Erlbaum Associates; 1988.32. Gangestad SW, Haselton MG, Welling LM, Gildersleeve KA, Pillsworth EG, Burriss RP, Larson CM, Puts DA: How valid are assessments of conception probability in ovulatory cycle research? Evaluations, recommended standards, and theoretical implications. . Evol Hum Behav in press.33. Borenstein M: Introduction to meta-analysis. Chichester, U.K.: John Wiley & Sons; 2009.34. Gildersleeve KAF, Melissa R.; Haselton, Martie G.: Stopping to Smell Rosie: Women's Evaluations of Other Women’s Body Odor Depend on Targets’ Fertility and Hormonal Contraception Use 2015.35. Roney JR, Simmons ZL: Men smelling women: null effects of exposure to ovulatory sweat on men’s testosterone. Evol Psychol 2012, 10:703-713.36. Gildersleeve KA: Meta-analytic and Experimental Investigations of Shifts in Women’s Mate Preferences and Attractiveness across the Ovulatory Cycle. 2014.37. Thornhill R, Gangestad SW: The evolutionary biology of human female sexuality: Oxford University Press; 2008.38. Haselton MG, Gildersleeve K: Can Men Detect Ovulation? Cur Dir Psychol Sci 2011, 20:87-92.39. Pagel M: The evolution of conspicuous oestrous advertisement in Old World monkeys. Anim Behav 1994, 47:1333-1341.**40. Gangestad SW, Haselton MG: Human estrus: implications for relationship science. Curr Opin Psychol 2015, 1:45-51.This review examines recent evidence for changes across the ovulatory cycle in women’s sexual desires and behavior. It includes an outline of lingering mysteries and suggestions for future research.41. Alexander R, Noonan KM: Concealment of ovulation, parental care, and human social evolution. In Evolutionary Biology and Human Social Behavior: An Anthropological Perspective. Edited by Chagnon N, Irons W: Duxbury Press; 1979:436-453. 42. Grebe NM, Gangestad SW, Garver-Apgar CE, Thornhill R: Women’s luteal-phase sexual proceptivity and the functions of extended sexuality. Psychol Sci 2013, 24:2106-2110.43. Strassmann BI: Sexual selection, paternal care, and concealed ovulation in humans. Ethol Sociobiol 1981, 2:31-40.44. Pillsworth EG, Haselton MG: Women's sexual strategies: The evolution of long-term bonds and extrapair sex. Annu Rev Sex Res 2006, 17:59-100.45. Huchard E, Cowlishaw G: Female–female aggression around mating: an extra cost of sociality in a multimale primate society. Behav Ecol 2011:arr083.46. Gildersleeve K, Haselton MG, Fales MR: Meta-analyses and p-curves support robust cycle shifts in women’s mate preferences: Reply to Wood and Carden (2014) and Harris, Pashler, and Mickes (2014). Psychol Bull 2014:1272-1280.47. Alvergne A, Lummaa V: Does the contraceptive pill alter mate choice in humans? Trends Ecol Evol 2010, 25:171-179.Fig. 1. Conception probability (fertility, probability of conceiving from an act of sexual intercourse), estradiol (ng/dL), and progesterone (ng/mL) values across the phases of the human ovulatory cycle. Average conception probability estimates are from Wilcox et al. (2001). Approximate hormone values are based on values reported in Garver-Apgar et al. (2008) but have been smoothed for ease of presentation. ................
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