Stress hormones help offspring adapt to harsher environments, biologist says

A wide variety of animals throughout the natural world pass along signals to their offspring in order to help them adapt to a world that may be much harsher to live in, according to a University of Windsor biologist.

During pregnancy such vertebrates as mammals, fish, reptiles and birds pass along stress hormones called glucocorticoids to their offspring, which helps prepare them for the reality that they’re coming into a world that may include dramatic changes in temperature, scarcer food availability, pollution, deforestation, and habitat destruction, said Oliver Love, an assistant professor in Biological Sciences who studies behavioural ecology.

“This is a way to help manage their expectations,” said Dr. Love, who recently published a paper on the subject called “Determining the adaptive potential of maternal stress” in the academic journal Ecology Letters. “They’re adjusting their bodies to deal with the reality of some very bad circumstances when they’re born.”

Harsh conditions for pregnant mothers causes maternal stress which elevates those hormones and help offspring – which are often smaller, weigh less, develop more slowly and are fewer in numbers – adapt to their environment, said Love, who co-authored the paper with Michael Sheriff, a visiting research fellow in his lab.

“These stress hormones are very good at integrating information from all of these stressors that are affecting a mother,” said Love, who will discuss the subject this afternoon on CJAM, the campus community radio station. “The offspring are listening to signs from their mother to gauge how bad the environment is going to be. It gives them a pre-emptive signal for what the world is going to be like.”

Love and Sheriff reviewed findings on the phenomenon from their own research on a variety of birds and hares, as well as the findings from other scientists on tropical fish and lizards. And while the research shows stress hormones help offspring adapt, those findings should not be misinterpreted.

“The message is not that we can do whatever we want to the environment,” he said. “The animals are just making the best of a bad situation. It’s a coping mechanism. They’re making changes in order to survive. They’re surviving, but they’re still not doing nearly as well as an unstressed mother, or unstressed offspring.”

Love will appear today on Research Matters, a weekly talk show that focuses on the work of University Researchers and airs every Thursday at 4:30 p.m. on CJAM 99.1 FM.