Tucker said that humans are “notable” among mammals in that they do not have what scientists call “fixed action patterns” with motherhood, patterns that other species have.

Tucker said that humans are “notable” among mammals in that they do not have what scientists call “fixed action patterns” with motherhood, patterns that other species have.

“We are just beginning to understand what makes moms moms,” Tucker said. “And that’s to the detriment of the human species.”