Researchers have found that when the conditions are right, cuckolded males in many species actually stick around to provide paternal care to their wife's bastard children.
This finding seems to go against the process of natural selection, which, one would think, would leave males only willing to care for those who will carry on their own genes.
Sure enough, the decision to care for the baby is by no means an easy one.
According to those who participated in the study - a team from Lund University, Yale University and the University of Oxford, there are several variables for these burdened males to consider, such as whether offering their care will hurt their future chances at reproduction.
"These are complex calculations that males are making and it has been difficult to measure things correctly, but looking across species has helped us work out what is going on," Charlie Cornwallis from the Department of Biology at Lund University said in an article posted on the school's website.
In all, the team looked at 62 studies of 48 different species, including insects, fish, birds and mammals.
Despite the variety of approaches to childcare each animal takes, the trend was the same: males were more willing to take care of their unfaithful wife's offspring when the risk of cuckoldry is generally low or caring does not harm their future reproductive success.
"This to me shows the strength of natural selection, with its footprints clear in species as different as burying beetles, which care for young over a few weeks by regurgitating dead mice, to humans that spend years providing for their children" Cornwallis said.
Knowing this, future researchers can now focus on testing these theories and predicting how males in other species may behave.
"Our study includes data from all species looked at so far and so provides a future guide to the types of species and experimental cues that are best to examine when conducting more detailed studies of paternal care," Cornwallis said.
The study was published in PLOS Biology.