Dear Guys...

...The next time you brag about how big your balls are, consider this: Big testicles, fellas? She'll cheat on you. Tiny balls? She won’t, say scientists

"According to scientists at the University of Oslo, big balls are more likely to mean a fella has an unfaithful partner.

Assistant Professor Petter Bøckman pointed to the example of gorillas, who have "tiny" testicles.

There is only one male in troops of gorillas, unlike fellow apes bonobos, who mate in large groups.

As such, bonobos have particularly large testicles with the aim of increasing their sperm count, giving them a greater chance of becoming dads."

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"“We can determine the degree of fidelity in the female by looking at the size of the male’s testicles," said Prof. Bøckman, reports Phys.org.

"The less faithful the female, the larger the male’s testicles.

"If the male will only fertilise one female and has no competitors, he only needs sufficient sperm to reach the egg.

"If the female mates on the side, it is smart to have as many cars as possible in the race.

"Then, the male must have testicles that are as large as possible."

Hmmmm. I think they've got it backwards. The philandering males part comes first. What's good for the goose...