Among bisexual men dating women, 49 percent said they would be most bothered by the sex.
For comparison, only 16 percent of men dating men said that the sex would bother them more than the emotional betrayal.
Scherer also said he wants to extend the research over time.
If the reproductive threat hypothesis is correct, a bisexual man dating a man will be more concerned about emotional fidelity, but if he breaks up with his male partner and starts dating a woman, his concerns should flip, with sexual jealousy becoming more prominent.
She covers the world of human and animal behavior, as well as paleontology and other science topics.
Stephanie has a Bachelor of Arts in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.
Other research has lent credence to the idea that jealousy depends on relationship type.
But if that same man is dating a woman, he can't be entirely sure that any baby she has is his, which could have led to more anxiety about sexual fidelity.
[5 Myths About Gay People Debunked] "Bisexuals kind of fit both aspects of this jealousy," Scherer told Live Science.