This article in Scientific American explains what researchers found.:
A quote from that article – also partially referenced by another poster.
Adams and his colleagues’ interpretation of these plethsymograph findings have not gone unchallenged. For example, in an article published in a 2006 issue of the Journal of Research in Personality, Gettysburg College researcher Brian Meier and his colleagues argue that Adams’s findings can be better interpreted as the homophobic group’s “defensive loathing” of gay males rather than a secret attraction. Drawing an analogy to other phobias, Meier and his coauthors state that, “We believe it is inaccurate to argue that spider phobics secretly desire spiders or that claustrophobics secretly like to be crammed into dark and tight spaces.” These investigators reason that Adams’s homophobic sample experienced erections in response to the gay male porn due not to sexual arousal, but due to their anxiety over the images, which in turn provoked the physiological response of penile engorgement.
I've never met anyone IRL or online who is genuinely homophobic
; all so-called "homophobes" are anti-gay but are mislabeled with a supposedly PC term.
Meier draws a false – and ridiculous – analogy to genuine phobics. Any adult male who has felt strong fear knows that, in fact, the male genitalia contract, not expand, with fear.
Also, a brief perusal of a web search indicates that, while human sexuality is quite 'interesting', the overall thrust
of the articles about anxiety and sexual arousal regards paraphilias
and sexual dysfunction.
There was no "defensive loathing" of gay males by the anti-gay males; there was only self-loathing and sexual arousal towards other males.
As for the supposed "infectious" nature of homosexuality.
http://williamapercy.com/wiki/images/Prison_Homosexuality_and_Its_Effect.pdf A report into homosexuality in prisons (1976) worth a read as background.
This supports what I've read of the Kinsey sexuality studies and refutes any possible "infection".
of the male population might, under some conditions, engage in homosexual acts but only a much smaller percentage will continue those acts throughout their lives. That smaller percentage seems to be roughly one quarter (maybe smaller). This means that three fourths (or more) who have tried homosexuality do not continue to engage in it on a regular basis. If the same conditions arise they may resume the activity but will not under normal circumstances. If the behavior were infectious then a much larger percentage would remain homosexual. They do not. It is not infectious.
IMO this points to roughly half of all men having the genetic potential for homosexuality but some environmental factors affect the expression of that potential. If this is correct then roughly half of all males are straight, most of the other half are bisexual and a small percentage are gay in orientation.
I suspect that at least 40% of all males have the genetic potential for homosexuality but I doubt more than 60-65% have the potential – these are my personal speculations.