The deep bass tones of singer Barry White have become synonymous with seduction among humans, but it appears horses find deep voices sexy too.
A new study has found that female horses are more attracted stallions with deeper, lower pitched whinnies.
The lower frequency ‘voices’ of stallions tended to be associated with larger males, who had a calmer temperament and their offspring tended to survive for longer.
The researchers say that mares seem to make their choices about unfamiliar males on their first meeting based on the depth of their voices.
And just like humans putting on an album featuring Barry White’s bass-baritone voice, the deeper whinnies from male horses also appear to get the mares more in the mood.
The researchers say the findings could also be used to help horse breeders select the best stallions for mating in the future.
Professor Alban Lemasson, a biologist at the University of Rennes in France, said: ‘The lower pitched the stallion’s voice, the slower its heart beat and the higher its reproductive success.
‘Stallion acoustic signals may play a role in female attraction at the time of group formation, as well as a role in sexual stimulation or libido maintenance when a group is formed.
‘This supports preliminary findings showing that females base their approach preference towards certain unfamiliar males on the amount of vocal signals uttered during their first encounter and some male vocal signals trigger mare behavioural preparation for mating, for example tail lifting and leg parting.’
In the wild, horses tend to live in harems consisting of one to two male adults and two to three females who have established stable bonds.
When female juveniles reach sexual maturity they leave their group and form their own harem with bachelor males or join an existing harem.
This may explain why ‘voice’ has become such an important characteristic in horses as females will often choose which harem to join from a long way off.
Sound is an effective way for males to convey information to prospective mates and may be a way of avoiding the often violent fights that wild male rivals can engage in to win a mate.
The singer Barry White was known as the Walrus of Love due to his deep voice and reputation for singing romantic songs, but it seems he may have been copying a style of seduction already employed by male horses.
In a study published in the journal Public Library of Science One, Professor Lemasson and his colleagues recorded the calls of 15 breeding stallions from stud farms around France.
They took blood and sperm samples from each of the horses and measured their heart beat.
The researchers then played the recordings to 40 adult mares aged between seven and 27 years old at the Haras National du Pin in France.
The females were placed in a corridor with a speaker at either end, through which a pair of whinnies from different stallions were played.
The researchers found that the females tended to move with preference towards the speak playing the deeper whinnie.
They also found that the males with deeper whinnies tended to be larger – suggesting they were stronger and so better able to protect the harem.
They also had slower heart beats, meaning they were calmer and fewer of their offspring tended to die before or shortly after birth.
Professor Lemasson said: ‘Lower heart beat rates are found in calmer situations and in calmer individuals.’
The preference among female horses for deep voices is not unique. Female humans have been found to find men with lower voices more attractive.
Koalas, bison and giant pandas have also been found to be more attracted to males with deeper calls.
Professor Lemasson added: ‘Our data also confirm that not all male voices are equally attractive, opening new lines of bioacoustic research on mammal reproduction.’
Originally written by Richard Gray at the UK Daily Mail.