More and more people say they are bisexual – meaning they’re sexually attracted to both men and women.
According to the most recent official stats, 987,000 UK people 16 or over (1.8 per cent of the population) identify as bisexual – up from 457,000 (0.9 per cent) in 2018.
However, the true number of people having both same-sex and opposite-sex encounters is actually much higher, a scientist suggests.
Dr Jason Hodgson, anthropologist and evolutionary geneticist at Anglia Ruskin University, thinks most people are ‘in the bisexual range’ – much like our primate relatives living wild in the jungle.
He says sexuality is a spectrum, from exclusively heterosexual at one end, through the bisexual range, to exclusively homosexual at the other end.
Heterosexuality and homosexuality are at the extremes of this spectrum, so most people should be somewhere in the middle in that they have sex with both men and women.
‘I predict that most people should actually be bisexual,’ Dr Hodson told MailOnline.
‘The genes that influence same sex sexual behaviour are probably just genes that influence general sociality, and people in the middle of the range of variation are probably better at all social relationships.
Bisexuality has sometimes been challenged, based on a popular assumption that men are either straight or gay, with nothing in between (file photo)
Official stats reveal 987,000 UK people aged 16 or over (1.8 per cent of the population) identify as bisexual – up from 457,000 (0.9 per cent) in 2018
‘Therefore people who would engage in same-sex sexual behaviour in some situations are probably also better at forming heterosexual relationships.’
To elaborate further, the academic imagines a sexuality spectrum running from 0 to 1, denoting the proportion of same-sex experiences out of all sexual experiences.
A person with a value of zero would have 0 per cent same-sex experiences, and 100 per cent heterosexual experiences, while a person with a value of 1 would have 100 per cent same-sex experiences and 0 per cent heterosexual experiences.
‘Those are the homosexual and heterosexual extremes of the scale,’ he said.
‘Everything in between would be in the bisexual range – some proportion of same sex, and some proportion of opposite sex sexual experiences.
‘So if a person had one homosexual experience and 99 heterosexual experiences their value would be 1/100 or 0.01 – just slightly in the bisexual range.
‘I suspect most people would be slightly in the bisexual range if given the right social circumstances.’
Dr Hodgson stresses that there’s a ‘very important distinction’ between identifying as bisexual and engaging in bisexual behaviour.
New data reveals a ‘large increase’ in young people in Britain saying they are bisexual, according to the Office for National Statistics (file photo)
Bonobos are one of the few species in which all adult members of one sex engage in habitual same-sex sexual interactions that occur at similar or even greater frequencies as opposite-sex interactions. Pictured, two young male African Bonobo chimpanzees (Pan Paniscus)
So although official new data reveals 1.8 per cent of UK adults identify as bisexual, the proportion of people who have are truly bisexual is likely much higher.
‘For example, people who identify as 100 per cent heterosexual might still have had a consenting same sex sexual experience at some time in their lives,’ Dr Hodgson told MailOnline.
‘These people would fall into the bisexual range of the behavioural scale.’
The expert points to one of our closest living relatives in the wild, the bonobo, which has high rates of has same-sex and opposite-sex encounters.
Bonobos are one of the few species in which all adult members of one sex engage in habitual same-sex sexual interactions that occur at similar or even greater frequencies as opposite-sex interactions.
They are known for the large variety of ‘social’ sexual acts that both males and females perform, including genito-genital rubbing and fellatio.
‘Bonobos are bisexual, and this is thought to contribute to group cohesion,’ the academic wrote in a 2016 research paper.
‘Bisexuality may be the norm, as those individuals involved in homosexual sex often also take part in reproductive sex.’
Pictured, several male chimpanzees mounting one another before intergroup encounter, Kibale forest, Uganda
According to Dr Hodgson, sex plays an important social role in other primates, but none more so than humans.
Whether we’re having same-sex or opposite-sex interactions, Dr Hodgson says that our sexual behaviour is carried in our genes.
‘Sexuality runs in families (it is heritable), and there are many, many genes involved each of which only has a small influence,’ he told MailOnline.
‘Genes that influence same-sex sexual behaviour are common, and most everyone has them to a lesser or greater degree.’
Ultimately, sexual acts between same-sex friends and opposite-sex friends could become more common and less of a taboo.
Bisexuality as a concept has sometimes been challenged, based on a popular assumption that men are either straight or gay, with nothing in between.
A controversial study from 20 years ago appeared to dispute the existence of bisexuality, although its study authors later doubled-back on their findings.
What’s more, bisexuality in the animal kingdom may be generally under-reported.
The existence of male bisexuality is contested by some, with sceptics claiming that men who self-identify as bisexual are actually either homosexual or heterosexual
There may be a lack of witness accounts of a single animal engaging in both homosexual and heterosexual acts.
Instead, a same-sex encounter may be recorded as homosexuality and and an opposite-sex encounter as heterosexuality.
John Sylla, president of the American Institute of Bisexuality, said people who are ‘purely straight or purely gay’ can often ‘generalise their own experience’ and think all other people ‘must be one or the other’.
Also, there may be people who describe themselves as straight or gay who may actually be bisexual, he suggested.
‘There are bisexually aroused men and women, even if for different reasons they choose to pass as just straight or gay,’ he said.
