Research into animal evolution has shown that a genetic formula led some non-monogamous animal species to adopt monogamy.
The researchers have been able to identify a common genetic formula for animal evolution which has turned non-monogamous animals to monogamy. The genetic formula led to pair bonds and co-parenting in five vertebrate species that behave monogamously.
Rebecca Young is a research associate in UT Austin’s Department of Integrative Biology and the first author of the study published in Proceedings of the National Academy of Sciences. She said: “Our study spans 450 million years of evolution, which is how long ago all these species shared a common ancestor.”
Young added: “Most people wouldn’t expect that across 450 million years, transitions to such complex behaviours would happen the same way every time.”
Monogamy in animals is defined by the study authors as forming a pair bond with one mate for at least one mating season, sharing at least some of the work of offspring raising and defending the young together from predators and hazards.
Researchers still consider animals monogamous if they occasionally mate with another animal.
The researchers studied five pairs of closely related species. These were four mammals, two birds, two frogs and two fish, each with one monogamous and one non-monogamous member.
The five pairs represent five times in the evolution of vertebrates that monogamy arose independently. One example is when the non-monogamous meadow voles and the close relatives the monogamous prairie voles diverged into separate species.
Despite the complexity of monogamy, they found that the same changes in gene expression occurred each time monogamy arose.
By assessing the similarities of genetic sequences, the team was able to identify the common evolutionary genetic formula that led to pair bonds and co-parenting in the five monogamous animal species.