Voice pitch and semen quality

The effect was small, but, nonetheless quite interesting. If semen quality is linked to the probability of a pregnancy per copulation, and if voice attractiveness is linked to the expected number of copulations, then it's easy to see how a tradeoff between voice attractiveness and semen quality might work.

PLoS ONE 6(12): e29271. doi:10.1371/journal.pone.0029271

Low Pitched Voices Are Perceived as Masculine and Attractive but Do They Predict Semen Quality in Men?

Leigh W. Simmons et al.

Women find masculinity in men's faces, bodies, and voices attractive, and women's preferences for men's masculine features are thought to be biological adaptations for finding a high quality mate. Fertility is an important aspect of mate quality. Here we test the phenotype-linked fertility hypothesis, which proposes that male secondary sexual characters are positively related to semen quality, allowing females to obtain direct benefits from mate choice. Specifically, we examined women's preferences for men's voice pitch, and its relationship with men's semen quality. Consistent with previous voice research, women judged lower pitched voices as more masculine and more attractive. However men with lower pitched voices did not have better semen quality. On the contrary, men whose voices were rated as more attractive tended to have lower concentrations of sperm in their ejaculate. These data are more consistent with a trade off between sperm production and male investment in competing for and attracting females, than with the phenotype-linked fertility hypothesis.

Link

Loss of air sacs and hominin speech

Journal of Human Evolution
doi:10.1016/j.jhevol.2011.07.007

Loss of air sacs improved hominin speech abilities
Bart de Boer

Abstract
In this paper, the acoustic-perceptual effects of air sacs are investigated. Using an adaptive hearing experiment, it is shown that air sacs reduce the perceptual effect of vowel-like articulations. Air sacs are a feature of the vocal tract of all great apes, except humans. Because the presence or absence of air sacs is correlated with the anatomy of the hyoid bone, a probable minimum and maximum date of the loss of air sacs can be estimated from fossil hyoid bones. Australopithecus afarensis still had air sacs about 3.3 Ma, while Homo heidelbergensis, some 600 000 years ago and Homo neandethalensis some 60 000 years ago, did no longer. The reduced distinctiveness of articulations produced with an air sac is in line with the hypothesis that air sacs were selected against because of the evolution of complex vocal communication. This relation between complex vocal communication and fossil evidence may help to get a firmer estimate of when speech first evolved.

Link

Biological basis for musical scales

I find it fascinating that the two highest ranked scales are precisely the two ones allowed by Plato for his Republic:

Quite the reverse, he replied; and if so the Dorian and the Phrygian are the only ones which you have left.

I answered: Of the harmonies I know nothing, but I want to have one warlike, to sound the note or accent which a brave man utters in the hour of danger and stern resolve, or when his cause is failing, and he is going to wounds or death or is overtaken by some other evil, and at every such crisis meets the blows of fortune with firm step and a determination to endure; and another to be used by him in times of peace and freedom of action, when there is no pressure of necessity, and he is seeking to persuade God by prayer, or man by instruction and admonition, or on the other hand, when he is expressing his willingness to yield to persuasion or entreaty or admonition, and which represents him when by prudent conduct he has attained his end, not carried away by his success, but acting moderately and wisely under the circumstances, and acquiescing in the event. These two harmonies I ask you to leave; the strain of necessity and the strain of freedom, the strain of the unfortunate and the strain of the fortunate, the strain of courage, and the strain of temperance; these, I say, leave.

And these, he replied, are the Dorian and Phrygian harmonies of which I was just now speaking.

Then, I said, if these and these only are to be used in our songs and melodies, we shall not want multiplicity of notes or a panharmonic scale?

I suppose not.

CORRECTION: A reader correctly points out in the comments that the names of musical scales are a bit ambivalent, so I looked into the paper itself. By "Dorian" they mean do-re-mib-fa-sol-la-sib-do which corresponds to the ancient Phrygian mode (the peace-like one according to Plato). The ancient Dorian mode (the war-like one according to Plato) seems to correspond to the "Phrygian" one. So, as far as I can tell, the highest ranked is the ancient Dorian and the next highest-ranked is the ancient Phrygian one, but any music experts are free to chime in and correct me.

From the paper:

The 50 heptatonic scales with the highest mean percentage similarity among the >4×107 possible scales evaluated are shown in Table 3. Three of the seven heptatonic modes (see Figure 1) emerge at the top of this list. The Phrygian mode holds the highest rank followed by the Dorian mode and the Ionian mode (the major scale). The fourth ranked scale is similar to the Phrygian mode but contains a neutral second (12:11) instead of a minor second; this collection is the Husayni scale in Arabic music [27]. The Aeolian mode (the natural minor scale) and Lydian mode are the fifth and sixth ranked scales. The next three scales are similar to the Dorian mode but with slight alterations in one or two scale degrees. The seventh ranked scale may represent the Kafi scale in classical Indian music with an alternative sharp sixth scale degree [22]. The eighth ranked scale is the Kardaniya scale in Arabic music [op cit.]. Although the ninth ranked scale does not represent any well-known musical tone collection, the Mixolydian mode is ranked tenth. The Locrian, which is the least used of the Western modes, is ranked fiftieth. Thus both the five-note and seven-note scales preferred in much music worldwide comprise intervals that conform optimally to a harmonic series.

and:

In humans, vocal stimuli arise in a variety of complex ways, not all of which are harmonic. Harmonic series depend on vocal fold vibrations and are characteristic of the “voiced speech” responsible for vowel sounds and some consonants [1]. Although the relative amplitudes of harmonics are altered by filtering effects of the supralaryngeal vocal tract resonances to produce different vowel phones, the frequencies of harmonics remain unchanged [op cit.]. In consequence, the presence of a harmonic series is a salient feature of human vocalizations and essential to human speech and language. It follows that the similarity of musical intervals to harmonic series provides a plausible biological basis for the worldwide human preference for a relatively small number of musical scales defined by their overall similarity to a harmonic series.

PLoS ONE doi:10.1371/journal.pone.0008144

A Biological Rationale for Musical Scales


Kamraan Z. Gill, Dale Purves

Abstract

Scales are collections of tones that divide octaves into specific intervals used to create music. Since humans can distinguish about 240 different pitches over an octave in the mid-range of hearing [1], in principle a very large number of tone combinations could have been used for this purpose. Nonetheless, compositions in Western classical, folk and popular music as well as in many other musical traditions are based on a relatively small number of scales that typically comprise only five to seven tones [2]–[6]. Why humans employ only a few of the enormous number of possible tone combinations to create music is not known. Here we show that the component intervals of the most widely used scales throughout history and across cultures are those with the greatest overall spectral similarity to a harmonic series. These findings suggest that humans prefer tone combinations that reflect the spectral characteristics of conspecific vocalizations. The analysis also highlights the spectral similarity among the scales used by different cultures.

Link

Female voice pitch and ovulation

Biol Lett. 2008 Oct 8;

Vocal cues of ovulation in human females.

Bryant GA, Haselton MG

Recent research has documented a variety of ovulatory cues in humans, and in many nonhuman species, the vocal channel provides cues of reproductive state. We collected two sets of vocal samples from 69 normally ovulating women: one set during the follicular (high-fertility) phase of the cycle and one set during the luteal (low-fertility) phase, with ovulation confirmed by luteinizing hormone tests. In these samples we measured fundamental frequency (pitch), formant dispersion, jitter, shimmer, harmonics-to-noise ratio and speech rate. When speaking a simple introductory sentence, women's pitch increased during high- as compared with low-fertility, and this difference was the greatest for women whose voices were recorded on the two highest fertility days within the fertile window (the 2 days just before ovulation). This pattern did not occur when the same women produced vowels. The high- versus low-fertility difference in pitch was associated with the approach of ovulation and not menstrual onset, thus representing, to our knowledge, the first research to show a specific cyclic fertility cue in the human voice. We interpret this finding as evidence of a fertility-related enhancement of femininity consistent with other research documenting attractiveness-related changes associated with ovulation.

Link

Women with high-pitched voices are more attractive

Perception. 2008;37(4):615-23.

The role of femininity and averageness of voice pitch in aesthetic judgments of women's voices.

Feinberg DR, DeBruine LM, Jones BC, Perrett DI.

Although averageness is preferred in auditory stimuli (eg music) and non-face objects (eg wristwatches), exaggerated feminine characteristics are preferred to averageness in female faces. To establish whether or not men prefer femininity in female voices to average characteristics, we conducted a correlational study (study 1) to assess the relationship between voice pitch and attractiveness ratings. We found a positive linear relationship between voice pitch and attractiveness ratings. In study 2 we manipulated pitch in women's voices with low (lower than average), average, and high (higher than average) starting pitches and gauged men's preferences. Men preferred women's voices with raised pitch for all levels of starting pitch. These findings suggest that men prefer high voice pitch to average voice pitch in women's voices.

Link

Deep voiced-men have more children

You might want to read the blog post on What is your voice pitch after reading this article.

Biology Letters
10.1098/rsbl.2007.0410

Voice pitch predicts reproductive success in male hunter-gatherers

C.L. Apicella et al.

The validity of evolutionary explanations of vocal sexual dimorphism hinges upon whether or not individuals with more sexually dimorphic voices have higher reproductive success than individuals with less dimorphic voices. However, due to modern birth control methods, these data are rarely described, and mating success is often used as a second-rate proxy. Here, we test whether voice pitch predicts reproductive success, number of children born and child mortality in an evolutionarily relevant population of hunter-gatherers. While we find that voice pitch is not related to reproductive outcomes in women, we find that men with low voice pitch have higher reproductive success and more children born to them. However, voice pitch in men does not predict child mortality. These findings suggest that the association between voice pitch and reproductive success in men is mediated by differential access to fecund women. Furthermore, they show that there is currently selection pressure for low-pitch voices in men.

Link

What is your voice pitch?

Continuing the previous post, finally you have a way of figuring out what your voice pitch is, and to see how you measure up compared with other males.

According to the above cited article, the testees' recordings had:

mean length=17.9 s, mean F0=113.2 Hz, F0 range=85.6-154.6 Hz

F0 is a correlate of pitch and is the parameter that you must estimate.

According to the authors, testees had to read an excerpt from the Rainbow Passage:

When the sunlight strikes raindrops in the air, they act as a prism and form a rainbow. The rainbow is a division of white light into many beautiful colors. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is , according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond his reach, his friends say he is looking for the pot of gold at the end of the rainbow. Throughout the centuries people have explained the rainbow in various ways. Some have accepted it as a miracle without physical explanation. To the Hebrews it was a token that there would be no more universal floods. The Greeks used to imagine that it was a sign from the gods to foretell war or heavy rain. The Norsemen considered the rainbow as a bridge over which the gods passed from earth to their home in the sky. Others have tried to explain the phenomenon physically. Aristotle thought that the rainbow was caused by reflection of the sun's rays by the rain. Since then physicists have found that it is not reflection, but refraction by the raindrops which causes the rainbows. Many complicated ideas about the rainbow have been formed. The difference in the rainbow depends considerably upon the size of the drops, and the width of the colored band increases as the size of the drops increases. The actual primary rainbow observed is said to be the effect of super-imposition of a number of bows. If the red of the second bow falls upon the green of the first, the result is to give a bow with an abnormally wide yellow band, since red and green light when mixed form yellow. This is a very common type of bow, one showing mainly red and yellow, with little or no green or blue.

I have no idea which excerpt they used, so I said the whole thing, which took me around 90 seconds, as opposed to the 17.9 average recording length in their experiments.

Ok, so how do you do it?

First download the Praat software which is available for different platforms and then run it.

Then do "New->Record Mono Sound" and speak the passage into your microphone. Then do "Save to list".

Now, select the recording and click edit. In the new window that will appear, go to Pitch->Pitch Settings and set pitch range from 75 to 300Hz.

Then, select the part of your recording that you contains your speech by clicking at the beginning and dragging the mouse to the end.

Then View->Show Analyses and make the "Longest Analysis" as long as your recording.

Finally, Pitch->Get Pitch, and there you have it!

My own pitch is 119Hz over the entire passage. I did notice that as I was speaking and getting more impatient my voice started to rise in tone. I then calculated the pitch in the first half of the recording (117Hz) vs. the second half (121Hz) and indeed it seemed that this was the case. In the first 17.9 seconds of the recording, which corresponds to the mean length of the authors' recordings, my pitch was 116Hz.

Leave comment or trackback if you manage to get through the process; it's easier than might seem from the above description.

Update

David Puts, first author of this study writes in the comments:

In response, to Jason Malloy's question, the male participants were racially mixed--mostly white, but maybe 10 (out of 111) black. I didn't find a significant difference in F0 between ethnicities.

Regarding Gaius' question, yes, Dabbs and Mallinger (1999) (cited in the paper) found a significant correlation between circulating testosterone levels and F0 in males of this age group. And Need et al. (1993) (also cited in our paper) found that testosterone treatment lowers voice pitch.

Finally, I think we sound kind of whiny on voicemail recordings, etc. because the microphones on these devices are not the best quality and don't pick up the entire sound spectrum very well.

Thanks for your interest!

The pitch of male voices

Evolution and Human Behavior (Article in Press)

Dominance and the evolution of sexual dimorphism in human voice pitch

David Andrew Puts et al.

Abstract

The developmental and anatomical causes of human voice sexual dimorphisms are known, but the evolutionary causes are not. Some evidence suggests a role of intersexual selection via female mate choice, but other evidence implicates male dominance competition. In this study, we examine the relationships among voice pitch, dominance, and male mating success. Males were audio recorded while participating in an unscripted dating-game scenario. Recordings were subsequently manipulated in voice pitch using computer software and then rated by groups of males for dominance. Results indicate that (1) a masculine, low-pitch voice increases ratings of men's physical and social dominance, augmenting the former more than the latter; and (2) men who believe they are physically dominant to their competitor lower their voice pitch when addressing him, whereas men who believe they are less dominant raise it. We also found a nonsignificant trend for men who speak at a lower pitch to report more sexual partners in the past year. These results are consistent with the hypothesis that male intrasexual competition was a salient selection pressure on the voices of ancestral males and contributed to human voice sexual dimorphism.

Link