In the first year of life, babies ideally form a secure attachment with their parents, but how does that process work and what does it look like? Researcher and writer Bethany Saltman began a deep exploration of the science behind that bond after her daughter Azalea was born. In an excerpt from her book Strange Situation: A Mother's Journey into the Science of Attachment, she looks at how imprinting begins even before birth in goslings, and finds similar patterns at work between human mothers and babies.

When the future Nobel Prize–winning scientist Konrad Lorenz was a young boy in Austria, his neighbor gave him a day-old duck. He was delighted to see that the duck seemed to treat him more like a parent than a member of a different species. As a boy, Lorenz didn’t just love animals; he wanted to be one, and a greylag goose specifically.

Years later, in 1935, when Lorenz was a thirty-two-year-old physician, still obsessed with animals in general and birds in particular, he published his most famous paper: “Der Kumpan in der Umwelt des Vogels” (The Companion in the Bird’s World). He had observed almost thirty species of birds living in and around his parents’ Austrian estate and had cataloged their behaviors. Eventually he began raising some of their chicks. In the paper, he describes the experiment wherein he divided a clutch of goose eggs (seven to ten) into two batches — one to be raised by its mother in the usual fashion, the other to be raised by him as he mimicked the clucks and coos of the mother goose. He would call to his small flock with a nasal and slightly syncopated “CAW-caw-caw. CAW-caw-caw-caw-caw.” They would run, and later fly, to his feet.

When goose chicks are born, they turn to the first moving creature they see for protection and care. This evolves into the chicks identifying that creature — whether goose or human — as their mother. They learn to track their mother by the sound of her voice. Which is how he discovered that the little goslings followed whomever they saw first—a genetic propensity that farmers had long noted but Lorenz actually named. He called it “imprinting.” And he found that there was a period of twelve to seventeen hours after birth in which the gosling and many other birds would attach to whatever creature they saw first. It was love at first sight. And after about thirty-two hours, it was an endless love: regardless of who fed the little chicks, they would return to their original “mother.” Food could be used to reward the birds and enhance the imprinting that had already occurred, but it was not the main motivator.

Read the full excerpt on Romper