We now know why a belly button becomes an ‘innie’

Scientists have discovered a new abdominal structure called the umbilical sheath, which anchors the remnant of the umbilical cord to deep abdominal tissues and helps determine the shape of your navel

​Scientists have discovered a new abdominal structure called the umbilical sheath, which anchors the remnant of the umbilical cord to deep abdominal tissues and helps determine the shape of your navel Scientists have discovered a new abdominal structure called the umbilical sheath, which anchors the remnant of the umbilical cord to deep abdominal tissues and helps determine the shape of your navel