What's next when you're the one who cheated on your partner

By Ian Kerner, CNN

Updated 1757 GMT (0157 HKT) February 26, 2019

Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.

Humans are now mostly monogamous, but this has been the norm for just the past 1,000 years.<br /><br />Scientists at University College London believe monogamy emerged so males could protect their infants from other males in ancestral groups who may kill them in order to mate with their mothers.
Photos: Which animals are monogamous?
Humans are now mostly monogamous, but this has been the norm for just the past 1,000 years.

Scientists at University College London believe monogamy emerged so males could protect their infants from other males in ancestral groups who may kill them in order to mate with their mothers.
Hide Caption
1 of 10
Scientists in Canada recently suggested that a rise in sexually transmitted infections, as social groups became larger among early humans, would have put pressure on staying monogamous in terms of mating behavior.
Photos: Which animals are monogamous?
Scientists in Canada recently suggested that a rise in sexually transmitted infections, as social groups became larger among early humans, would have put pressure on staying monogamous in terms of mating behavior.
Hide Caption
2 of 10
Primates such as chimpanzees and bonobo monkeys, pictured, do not conform to a mating system and regularly engage in frequent sex with multiple partners.
Photos: Which animals are monogamous?
Primates such as chimpanzees and bonobo monkeys, pictured, do not conform to a mating system and regularly engage in frequent sex with multiple partners.
Hide Caption
3 of 10