Scientists have identified a universal code in the genes of some animals that appears to control whether or not they are committed to a single mate.
Monogamy In The Animal Kingdom
In a study published in the journal Proceedings of the National Academy of Sciences, study researcher Hans Hoffman, from The University of Texas at Austin, and colleagues found evidence that genetic drivers may have a role in monogamous bonds.
Although monogamy can be defined in many ways, the researchers focused on animals that paired up for at least one mating season, shared parental care duties, and worked together to protect their offspring from predators.
The researchers wanted to know why certain animal species have monogamous relationships while others lived more promiscuously, so they studied five pairs of closely related species: two birds, four mammals, two frogs, and two fish.
Genes In Monogamous Animals
The researchers observed a pattern in the monogamous animals. They found that these creatures have certain sets of genes that were more likely to be turned up or turned down in the brain than in the non-monogamous species.
"We compare neural transcriptomes of reproductive males in monogamous and nonmonogamous species pairs of mice, voles, parid songbirds, frogs, and cichlid fishes," the researchers wrote in their study, which was published on Jan. 7. "Our results provide evidence of a universal transcriptomic code underlying monogamy in vertebrates."
Monogamy And Brain Development
Among the genes with increased activity in monogamous species, the researchers found those involved in neural development, learning, memory, and signaling between cells.
The researchers speculate that genes that make the brain more adaptable and capable to remember may also help animals recognize their mates, their offspring, and the home they share.
"What evolution came up with is brilliant," Hoffman said. "When we enter into a pair bond, or have offspring we must take care of, we find it rewarding. The reward system gets hijacked. It says, 'Hey, I love this shit.'"