Can I adopt my stepchild without the father’s consent?

A sense of identity is considered to be a crucial part of a child’s wellbeing, so step-parent adoption is, on the whole, to be welcomed. There are many reasons someone may want to adopt their stepchild, not least to show commitment to the family unit and to make important decisions in the child’s life. But what happens if the child’s biological father objects? Can a stepchild be adopted without their consent?