She demonstrated this to me in her office, puckering her lips and filling the room with an undulating, wolf-like sound. I tried to copy her, she offered tips for improvement, and for a while we sat there, howling at each other. Later, I saw her howl at two babies and newborn Joris, none of whom she’d met before. One of the babies laughed with delight and seemed absolutely transfixed. The other stopped crying and relaxed. Newborn Joris turned his head to peer at the howling scientist, let out a deep sigh and fell asleep.

All parents, Dr. Wermke said, have an innate ability to understand and respond to their babies. Indeed, it was mothers who supported her research from the beginning, even as other scientists were skeptical. In the 1980s, when Dr. Wermke first began recording babies’ sounds, many researchers viewed crying as a mere biological alarm signal, worth investigating only in the context of problems such as colic. But mothers never doubted that their tiny babies were worth studying. As Judith Fricke, little Joris’s mother, said, “I think you’d recognize the sound of your own child among a hundred others. You develop an ear for that.”

And the howl? After returning from my trip, I tried it out on my 3-week-old nephew. My version was not as melodious as Dr. Wermke’s, but to my delight, it sort of worked. He snuggled against my shoulder and stopped crying – at least for a little while.

Sophie Hardach is a journalist and author living in London. Her next book, “Languages Are Good For You,” celebrates linguistic diversity. It will be published by Head of Zeus in 2020.