Study debates relationship of sexually

dimorphic traits and attractiveness

by Adam Fix '13
NEWS WRITER

Unlikely as it may seem, the resonance of our voices plays a direct role in our evolution as a species. On Tuesday, Feb. 22, Jeremy Atkinson and Nathan Pipitone lectured on the relation of vocal production to attractiveness in men and women and challenged the conception that sexually dimorphic traits directly indicate biological fitness.

According to Pipitone’s study, a lower, booming voice, like muscles or jaw structure, is associated with attractiveness in men and his fitness, or ability to produce offspring. Conversely, a higher voice is associated with femininity and associates with attractive female traits, such as a low waist-to-hip ratio. He refers to these characteristics as a “hypertrophy,” noting that an attractive voice very often belongs to a physically attractive person and states that there is “adaptive significance in having characteristically male or female voices.”

Seeking to observe vocal production’s relation to reproduction, Pipitone and Atkinson studied the Himba people in the Kunene region in Africa, whom Atkinson described as “a population that mimics human evolutionary history.” Female fitness varied inversely to vocal depth, and male fitness directly correlated to vocal depth. Like many sexually dimorphic traits in the animal kingdom, people exhibiting strong male or female traits produced more offspring.

However, Atkinson also provided a counterargument by studying grip strength amongst the Himba. He notes that although strong grips are considered attractive in males and unattractive in females, the Himba women with high grip strength exhibited far greater biological fitness. In citing the grandmother hypothesis, which studies the benefits post-reproductive aged females convey on a population, Atkinson asserted that high grip strength, while not attractive in females, allows them to better provide for their grandchildren, thus increasing fitness of the family as a whole.

Their study demonstrated that sexually dimorphic traits, although often considered physically attractive, do not always perfectly indicate the reproductive abilities of the individual.